MX Missile Basing

September 1981

NTIS order #PB82-108077
Library of Congress Catalog Card Number 81-600133

For sale by the Superintendent of Documents,

U.S. Government Printing Office, Washington, D.C. 20402
Foreword

This report, prepared at the request of the Technology Assessment Board,

reviews the various ways in which the new MX intercontinental balIistic missile

could be based, and assesses the technical issues, the advantages, and the disadvantages associated with each major option. I n order to do so, OTA explored a wide

variety of military technologies and issues, ranging from antiballistic missile defense

to antisubmarine warfare to the impact of major construction projects on arid

Western lands. OTA has made every effort to apply comparable assumptions and

criteria to the various options assessed, and to be explicit about identifying questions which simply cannot be resolved on technical grounds alone. Our purpose is to

assist Members of Congress in evaluating particular basing modes of interest to

them, and to permit comparison of alternatives.

OTA identified a wide variety of possible basing modes and evaluated them in

terms of: technical risk; degree of survivability; endurance; contribution to weapon

effectiveness; effectiveness of command, control, and communications; arms control impacts; institutional considerations; impacts on the deployment region; costs;

schedule; and impact on stability The concluding section of chapter 1 compares the

leading options in terms of a variety of criteria used, and it is apparent that a final

choice depends in large measure on the relative weight assigned to these criteria.

Five basing modes were found that appear feasible and offer reasonable prospects

of survivability, but none of them is without serious risks, high cost, important

uncertainties, or significant drawbacks. No basing mode appears Iikely to offer survivability for the MX much before the end of the current decade

Much of the research done for this assessment required the use of classified

sources. The material in this unclassified report is believed accurate, balanced, and

complete but security requirements have at times made it necessary to omit some of

the supporting technical analysis. OTA will shortly publish a classified annex to this

report, which wilI be available to qualified requesters.

OTA is grateful for the assistance of its MX Missile Basing Advisory Panel, the

cooperation of various components of the Department of Defense; the cooperation

of the General Accounting Office, the Congressional Budget Office, and the Congressional Research Service; the assistance of other U.S. Government agencies; and

the support of numerous individuals.

# ~ d ~

.

.

JOHN H GIBBONS

Director

.
MX

Stan

Missile Basing Advisory Panel

Harry Woolf, Chairman

Director, Institute for Advanced Study

ley Al brecht WilIiam Kincade

Professor and Editor of Rural Society Executive Director

Department of Sociology

Brigham Young University

Stephen T. Bradhurst

Director

Nevada MX Project Field Office

Russell E. Dougherty

General, USAF (retired)

Executive Director

Air Force Association

Sidney D. Drell

Professor and Deputy Director

Stanford Linear Accelerator Center

Henry M. Foley

Professor

Department of Physics

Columbia University

Kenneth E. Foster

Associate Director

Office of Arid Lands Studies

University of Arizona

Sanford Gottlieb

Kensington, Md.

Daniel O. Graham

Lt. Gen., USA (retired)

Director of Special Projects

American Security Council

Arms Control Association

Gordon Kirjassoff

President

Edwards and Kelcey

Kenneth C. Olson

Project Manager

Utah MX Coordination Office

Kenneth Smith

Lockheed Chief Engineer (retired)

John Toomay

Major General, USAF (retired)

WilIiam Van Cleave

Director

Defense and Strategic Studies

University of Southern California

J erorne Wiesner

Institute Professor

Massachusetts Institute of

Technology

James R. Woolsey, Esq.

Shea & Gardner

Note The Advisory Panel provided advice and comment throughout the assessment, but the members do not necessarily approve,

disapprove, or endorse the report for which OTA assumes full responsibility

Iv
MX Missile Basing Project Staff

Lionel S. Johns, Assistant Director, OTA

Energy, Materials, and International Security Division

Peter Sharfman

Program Manager, International Security & Commerce Program

Project Director (from january 1981 )

Jeremy Kaplan Project Director (to January 1981 )

Ashton Carter Forrest R. Frank* Antoinette Kassim* *

Marc Messing* Theodore Postol * Robin Staff in

Administrative Staf f

Helena Hassell Dorothy Richroath Jackie Robinson

Contractors

Abt Associates

Booz-Allen & Hamilton, Inc.

Lynda Brothers**

Energy and Resource Consultants, Inc.

The Institute of Ecology

Gerald Garvey

Barbara M. Heller

OTA Publishing Staff

Horizons Technology, lnc.

Hydra Corp.

John Muir Institute

J. Watson Noah, Inc.

Science Applications, Inc.

Peter Zimmerman* *

John C. Holmes, Publishing Officer

John Bergling Kathie S. Boss Debra M. Datcher Joe Henson

‘ 0TA contract personnel

‘ ‘0TA consultant
Contents

Chapter

1.

2

3.

4.

5.

6,

7.

8.

9.

1 0

11,

12.

Summary. .

Multiple Protect ive Shelter s

Ballistic Missile Defens e

Launch Under Attack , .

Small Submarine Basing of MX

Air Mobile Missile .

Surface Ship Basing of MX .

Land Mobile MX Basing. .

Deep Underground Basing .

Page

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

. . . . . . . . . . . . . . . . . . 33

. . . . . . . . . . . . . . . . . . . . . . 111

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147

. . . . . . . . . . . . . . . . . . . . . . 167

. . . . . . . . . . . . . . . . . . 217

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 257

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 269

Command, Control, and Communications (C’) . . . . . . . . .

Diversity of U.S. Strategic Faces

Arms Control Considerations and MX Basing

Appendixes

A. Letter of Request .

. . . . . 277

. . . . . . . . . . . . . . . . . 303

Options . .......311

. . . . . . . . . . . . . . . . . . . . . . . . . 325

B. MX Missile ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. ..328

C. Acronyms and Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. ....330
Chapter 1

SUMMARY

Chapter 1

SUMMARY

INTRODUCTION

The U.S. Air Force is developing a new intercontinental ballistic missile (ICBM) known as

the MX (fig. 1). Because the hardened “silos” in

which existing ICBMS are based are considered

increasingly vuInerable to a Soviet attack as a

resuIt of the improving accuracy of Soviet m issiles, Congress and the Department of Defense

(DOD) have agreed that a more survivable

mode than hardened silos shouId be found for

basing any new missile. OTA has examined a

variety of ways in which such a missile could

be based,

The purpose of this study is to identify MX

basing modes and to assess the major advantages, disadvantages, risks, and uncertainties

of each. At the outset of this study, OTA

Figure 1 .—MX Missile Characteristics

Missile Description

Length 71 feet

Diameter 92 Inches (7 feet 8 Inches)

Gross weight 1$2,000 Ibs

Number of reentry vehicles 10

SOURCE Off Ice of Technology Assessment

reviewed all the basing modes that could be

identified, including those addressed in past

DOD studies. On the basis of criteria of technical feasibility and the likely ability of each

basing mode to provide survivability against a

range of plausible Soviet threats, the Iist was

narrowed to 11 basing modes that were analyzed in detail, This report presents these

analyses, and also states briefly why other

possibilities were rejected. Detailed analyses

narrowed the range to five possibiIities:

1. multiple protective shelter (MPS) basing in

several variants,

2. antiballistic missile (ABM) defense of MPS

basing,

3. launch under attack,

4. basing on small submarines, and

5. basing on large aircraft.

There is a variety of criteria against which

these basing modes can be evaluated, though

there is no general agreement about their

relative importance. Indeed, since no basing

mode ranks highest against all the commonly

used criteria, deciding how to choose and

weigh the criteria of evaluation is the essence

of choosing a basing mode. To help Members

of Congress assign the most weight to those

criteria they consider most important, OTA has

compared these five basing modes separately

against these criteria in the last section of this

summary chapter.

OTA was requested by the Technology

Assessment Board to examine only basing

modes for the MX missile. For this reason, the

analysis does not address the questions of

whether and why the missile itself is needed, or

the relative merits of deploying additional

numbers of existing Minuteman III or Trident I

missiles. During the course of the study the

Board requested that an analysis of rebasing

the existing Minuteman i i i missiles in MPS to

increase their survivability be included. Since

the large size of the MX missile limits the ways

in which it could be based, OTA surveyed bas3
4 . Mx Missile Basing

ing modes that might be used for smaller missiles, but found none so attractive as to lead us

to seek a change in our terms of reference. It is

important to note that much of OTA’S analysis

is premised on the accuracy of U.S. intelligence about the capabilities and growth of

Soviet strategic forces. Due to the study

boundaries, OTA’S criteria of analysis and

comparison tend to use, rather than critically

evaIuate, conventional wisdom about how

modes, Congress should choose. OTA is therefore able to present the relevant technical information regarding each possibility without

the need to make and defend a choice. This

study provides data, analyses, and explanations that will assist Congress to understand

and evaluate the forthcoming Reagan admin istration proposal, whether this proposal turns

out to be a reaffirmation of the existing program as shaped by the Carter administration, a

strategic nuclear forces support U.S. national relatively minor mod

security. change in direction.

OTA does not have a recommendation as to

which basing mode, or combination of basing

fication, or a major

PRINCIPAL FINDINGS

1. There are five basing modes that appear

feasible and offer reasonable prospects of providing survivability and meeting established performance criteria for ICBMS. They are: 1) MPS

basing of the type now under development by

the Air Force or in one of several variants. MPS

basing involves hiding the missiles among a

much larger number of shelters, so that the

Soviets would have to target all the shelters in

order to attack all the missiles. If there were

more shelters than the Soviets could effectively target, then some of the missiles would survive. This approach was the choice of the

Carter administration, and one variant of MPS

is now under engineering development by the

Air Force. 2) MPS basing defended by a lowaltitude ABM system known as LoADS (Low

Altitude Defense System); 3) reliance on

launch under attack so that the missiles would

be used before the Soviets could destroy them;

4) basing MX on small submarines; and 5) airmobile basing in which missiles would be

dropped from wide-bodied aircraft and

launched while falling. As described below,

each of these alternatives has serious risks and

drawbacks, and it is believed that choosing

which risks and drawbacks are most tolerable

is a judgment that cannot be made on technical grounds alone.

2. No basing mode is likely to provide a

substantial number of survivable MX missiles

much before the end of this decade. WhiIe some

basing modes would permit the first missiles to

be operational as soon as 1986 or 1987, these

missiles could not be considered more survivable than the existing Minuteman missiles until

additional elements of the basing system were

in place.

3. MPS basing would preserve the existing

characteristics and improve the capabilities of

land-based ICBMS, but has three principal drawbacks.

●

●

MX missiles based in MPS would provide

better accuracy and endurance, and comparable responsiveness, time-on-target control, and retargeting capability, when compared to other feasible basing modes.

Survivability depends on what the Air

Force calls “preservation of location

uncertainty” (PLU), that is, preventing the

Soviets from determining which shelters

hold the actual missiles. PLU amounts to a

new technology, and while it might well

be carried out successfully, confidence in

PLU will be limited until prototypes have

been successfully tested. Even then Iingering doubts might remain.
Ch. l—Summary ● 5

●

●

MPS basing cannot ensure the survivability of the missiles unless the number of

shelters is large enough relative to the size

of the Soviet threat. The “baseline” system

of 200 MX missiles and 4,600 shelters would

not be large enough if the Soviets chose to

continue to increase their inventory of warheads. If the trends shown in recent Soviet

force modernization efforts continue into

the future, an MPS deployment of about

350 missiles and 8,250 shelters would be

needed by 199o to provide survivability.

Although the number of missiles and

shelters needed depends on what the

Soviets do, the Ieadtimes for construction

are so long that decisions on size must be

made before intelligence data on actual,

as distinct from possible, Soviet programs

are avaiIable.

MPS would severely impact the socioeconomic and physical characteristics of the deployment region. At a minimum, the deployment area would suffer the impacts

generally associated with very rapid

population growth in rural communities;

but larger urban areas would also be affected by economic uncertainties regarding the size of the MPS construction work

force and its regional distribution. The

physical impacts of MPS would be characteristic of the impacts of major construction projects in arid regions; but because

the grid pattern of MPS would mean that

a very large area would be close to construction activities, it is possible that

thousands of square miles of rangeland

could be rendered unproductive.

4. None of the variants of MPS would reduce

the risks and uncertainties associated with PLU or

significantly alter the number of shelters required. However, split basing or the selection of a

different deployment area would mitigate the

regional impacts. The variants that OTA examined include changes from horizontal to vertical shelters, from “individual cluster” to “vaIIey cluster” basing, and from Utah/Nevada

basing to basing divided between Utah/Nevada

and west Texas/New Mexico. A further variant

would be to construct additional silos in the

existing Minuteman basing areas to create a

Minuteman/MPS system. This construction

would be substantially cheaper than the proposed MX/MPS system, but would not be significantly quicker to construct.

5. A LoADS ABM system could effectively double the number of shelters in an MPS deployment

provided two conditions were met. A LoADS

system would have a high probability of shooting down the first Soviet warhead aimed at

each MX missile, forcing the Soviets to attack

each shelter with two warheads. The conditions for LoADS’ effectiveness are: 1 ) PLU both

for the MX and for the LoADS defense unit,

and 2) survival and operation of the defense in

the presence of nearby nuclear detonations.

Since the LoADS defense unit must be concealed in a shelter and must be indistinguishable from the missiles and the decoys, LoADS

deployment would compound the difficulties

of PLU. These difficulties would be greater still

if the LoADS addition were not planned at the

time the MPS system was being designed. The

LoADS defense unit would be required to endure nuclear effects of a severity unprecedented for so complex a piece of equipment.

A LoADS deployment would require the

United States either to seek amendment of, or

to withdraw from, the ABM Treaty reached at

SALT 1.

6. Basing MX missiles in silos and relying on

launching the missiles before a Soviet attack

could destroy them (launch under attack, or LUA)

would be technically feasible, but it would create

extreme requirements for availability of, and

rapid decisionmaking by, National Command Authorities. A substantial upgrading of existing

warning and communications systems would

be required to ensure this capability against a

determined Soviet attempt at disruption, Reliance on this capabiIity wou Id, however, impose extremely stringent requirements that the

President be in communication with both the

warning systems and the forces, and that an

unprecedentedly weighty decision be made in

a few minutes on the basis of information sup-
6 ● MX Missile Basing

plied by remote sensors. Finally, there would

always be concern about whether the system

was really immune to disruption or errors.

7. MX missiles based on small submarines

would be highly survivable. Submarine-based MX

would not be significantly less capable than landbased MX, but submarine-basing would involve a

reorientation of U.S. strategic forces. An MX

force based on small diesel-electric or nuclear

submarines operating 1,000 to 1,500 miles from

the U.S. coast could offer weapon effectiveness (i. e., accuracy, responsiveness, time-ontarget control, and rapid retargeting) almost as

good as land basing and would probably be

adequate to carry out any strategic mission. A

command, control, and communications (CJ

)

system to support submarine basing would be

different from that used for landbasing but

would not necessarily be less capable. However, submarine basing of MX would change

the relative importance of land- and submarine-based strategic forces. Although OTA

could find no scientific basis for predicting

such an occurrence, the possibility cannot be

excluded that an unexpected Soviet capability

in antisubmarine warfare that threatened the

U.S. force of Poseidon and Trident submarines

might also threaten a force of MX missiles on

small submarines. The cost of providing 100

MX missiles on alert at all times on a small submarine force would be roughly comparable to

the cost of the baseline MPS system, and

would be less than the cost of an MPS system

sized to meet a larger Soviet threat. A significant problem is that such a force of small submarines could not be constructed quickly; existing U.S. submarine construction programs

are already behind schedule, and delays might

arise from using shipyards which are not now

building submarines. It is therefore unlikely

that initial MX deployment on small submarines could take place before 1990. However, the first MX missiles deployed would be

survivable even before the rest of the deployment was complete.

8. An air-mobile MX-carried on wide-bodied

aircraft and launched in midair—would be survivable provided the aircraft received timely warning and took off immediately. Its dependence on

prompt response to timely warning of submarine-launched ballistic missile attack would

give such a force a common failure mode with

the bomber force. (Removing dependence on

warning by means of continuous airborne alert

wouId be prohibitively expensive; acquisition

and “1O years of operation for such a force

Could cost $80 billion to $100 billion (fiscal

year 1980 dollars). ) On the other hand, an air

mobile force could not be threatened by the

Soviet ICBM force unless the Soviets deployed

man}’ more ICBM missiles than they now

possess and used them to barrage the entire

Central United States. The outcome of such an

attack wouId be insensitive to Soviet improvement in the fractionation and accuracy of their

ICBMS. An air mobile MX force could not endure long after an attack if the Soviets attacked every airfield on which such planes

could land to refuel, In this case, the National

Command Authorities would have to “use or

lose” the MX missiles within 5 to 6 hours of a

Soviet attack. Providing endurance by increasing the number of airfields at which the planes

could refuel would be enormously expensive

($10 billion to $30 billion for up to 4,600 airfields), and growth of the Soviet threat to

plausible levels for the 1990’s would require so

many airfields that they would essentially fill

the continental United States. The aircraft

wouId have to take off to launch their missiIes,

which couId mean slow response time, longer

warning for the Soviets of a U.S. strike, and the

possibility that the Soviets would mistake

dispersal during a crisis for preparation for a

U.S. first strike. Warning, communications,

and guidance systems for an air-mobiIe force

could be complex.

9. The problems associated with other basing

modes studied by OTA appear more substantial.

An ABM defense of MX missiles based in fixed

silos against a large Soviet threat would require the use of a complex system based on

frontier technology and potentially vulnerable

to Soviet countermeasures. The technical risks

appear too high to support a decision today to

rely on such a system for MX basing. Basing

MX on surface ships appears to offer no serious advantages and significantly less survivability than submarine basing. Basing MX in
Ch. l—Summary ● 7

“superhardened” shelters (e. g., very deep

underground) would Iikely involve a period of

several days between a launch order and the

actual launch of the missile. Rail mobile MX

would involve problems of force management

and vu Inerabiity to peacetime accidents or

sabotage Road-mob i I e basing appears infeasible because of the size of the missile; off-road

mobile basing appears to offer few advantages

and several drawbacks compared to MPS.

10. In comparing MPS, MPS with LoADS, LUA,

small submarine basing, and air mobile, it is

found that:

●

●

●

●

●

●

All offer reasonable prospects for feasibilit y and survivabiIity MPS depends for surrevivability on concealing its location (PLU)

which creates a degree of technical risk,

and which wouId be become stiII more

cliff i cult if LoADS is used to defend MPS

All are compatible with high weapon effectiveness for the MX missile, although

MPS, MPS with LoADS, and LUA would

provide slightly better accuracy than submarine basing or air mobile.

MPS would endure in an operational condition for a long time if it survived; small

submarines would endure for several

months; air mobile might endure for only

a few hours, depending on the nature of

the Soviet attack; the endurance of

LoADS would depend on the speed and

effectiveness of surviving Soviet reconnaissance and retargeting capabilities;

LUA would have no endurance at all.

All are compatible with adequate C3

, but

obtaining such C3 for any of them would

require time, effort, and money.

MPS could complicate future arms control. MPS with LoADS would require

amending or withdrawing from the ABM

Treaty reached at SALT 1. LUA, small submarines, and air mobile appear compatible with existing arms control concepts.

MPS, or MPS with LoADS, would have an

impact on both the socioeconomic and

physical environment in the deployment

region that would be so great as to be different in kind from the impacts of any of

the other systems. LUA would have virtually no environmental impact. Impacts

from submarine basing and air mobile

would be relatively small and Iimited to

the areas of the operating bases,

Assuming a requirement for 100 surviving

MX missiles, costs of baseline MPS, submarine basing, and air mobile would be

roughly comparable: costs of acquisition

and 10 years of operations for nominal

designs are estimated to be roughly $40

billion (fiscal year 1980 dollars). Rebasing

Minuteman III in an MPS mode would

cost 10 to 20 percent less. Growth in the

Soviet threat would require increases in

the costs of MPS systems, but not in the

others. If the Soviet threat grew to a level

OTA considers plausible for 1990, the

United States could assure survivability of

the MX/MPS either by adding LoADS (at

an additional cost of $10 billion to $15

billion) or by expanding the number of

shelters and MX missiles (at an additional

cost of $15 billion to $20 billion). Continued growth of the Soviet threat into the

199o’s would drive the cost of survivability as high as $80 billion. Costs of LUA

would be the lowest: procurement of the

MX missiles, modification of existing silos,

and upgraded C3 and warning systems

could be $20 billion cheaper than the

alternatives.

MPS could provide a small, nonsurvivable

force by 1986 or 1987, and a large, survivable force by about 1990 MX deployment relying on launch under attack

could begin in 1986, but completion of

necessary upgrading of warning and C3

systems would require several years

longer. Air mobile could be deployed near

the end of the decade. MPS with LoADS

could be available around 1990, Small

submarines could be deployed beginning

around 1990, and would be survivable

immediately, Thus, none of the basing

modes could close the so-called “window

of vulnerability” before the end of the

decade,
8 ● MX Missile Basing

ELEVEN POSSIBLE BASING MODES

1. MX/MPS—The Current

Baseline System

I n the fall of 1979, the Carter administration

selected a basing mode for MX and decided to

proceed with full-scale engineering development. This design envisages the deceptive

deployment of 200 MX missiles in 4,600

hardened concrete shelters. If the Soviets

could not know which shelters contained the

actual MX missiles and which contained

missile decoys, they would have to target all

4,600 shelters in order to attack all 200

missiles. The baseline system would be located

in the Great Basin area of Nevada and Utah

and could be expanded by building additional

shelters, additional missiles, or both.

The shelters would be spaced roughly 1 mile

apart, and arranged in a linear grid pattern.

(Fig, 2 illustrates the schematic layout of a

single cluster. ) Each of the 200 missiles would

be based in separate clusters of 23 shelters.

The missiles would be transportable within

each cluster but could not be moved from one

cluster to another without removing large

earthen barriers. Each shelter would resemble

a garage or loading dock; the truck transporting a missile or decoy would back up to the

shelter entrance, and insert the missile or

decoy horizontally. Each cluster would thus

contain 1 MX missile, 22 decoys, 23 shelters, 1

large transporter truck, and 1 maintenance

facility. The truck would shuffle the missile

and the decoys among the shelters in such a

Figure 2.—Conceptual Cluster Layout

w

23 protective shelters

per cluster “

 typica l

SOURCE U S Air Force
Ch. l—Summary ● 9

way that the Soviets wouId be unable to determine which shelter contained the missile.

Missiles would also be transported for

maintenance or, possibly, to facIitate arms

control verification.

The MX missile in MPS basing has been

designed to set a new standard in military

capability. Its accuracy would be unprecedented, It could be rapidly retargeted in a

variety of ways, and would have precise timeon-target control. MPS basing wouId give MX a

very high alert rate and a long postattack endurance. As a system, MX/MPS would perform

its military function providing that two conditions were met: 1 ) preservation of location

uncertainty for the missile, and 2) adequate

size to meet the Soviet threat.

Preservation of Location Uncertainty (PLU)

The multiple shelters cannot ensure survival

of the requisite number of missiles if the Soviets

find out which shelters contain the missiles. PLU

therefore involves making certain that the

observable characteristics of missiles and

decoys are so nearly identical that an outside

observer cannot distinguish them, This design

entails a major new engineering task, driven by

the high sensitivity of present-day and future

sensors and by the many observable signs of the

missile’s presence. As an example of PLU engineering, the missile decoy might contain an

appropriate quantity and distribution of highpermeability metal to help make it impossible

to distinguish the missile from the decoys by

means of a metal detector.

Dealing with this and dozens of other potentially observable signatures makes PLU the

equivalent of a new technology, which is wide

in scope and intensive in detail. It would require

the integration of administrative, operational,

and technical considerations. One cannot have

confidence in the success of this “new technology” before equipment prototypes are fieldtested, because even fine details of missile

signatures are important for adequate missile

concealment. Furthermore, after the system is

fully designed, tested, and deployed, lingering

doubts could remain that would limit confi83- 4770-2

dence in the system. Even small doubts could be

important, since a catastrophic breakdown in

PLU (e. g., a technique whereby the Soviets

could determine the exact location of the

missiles by satellite observations) would make it

relatively easy to attack all the MX missiles; a

more Iimited breakdown, while not imperiling

the entire system, could improve the effectiveness of a Soviet attack and reduce the

weight of a U.S. retaliation. On the other hand,

the Soviets’ task of “breaking” PLU could be

difficult as well. For the Soviets to attack the

system on the basis of their own counter-PLU efforts might entail considerable risk and uncertainty on their part.

Except during missile transport, the proposed

baseline system would not restrict public activities outside the 2.5-acre sites surrounding

each shelter, While barring the public from a

larger area might be infeasible, restrictions on

public activities, including mineral exploration

and development, could be necessary. From a

technical standpoint, the nature and extent of

these restrictions depends on the degree of success of the Air Force PLU program.

Adequate Size in the

Face of Threat Growth

The principle of an MPS system is that survivability is maintained by having more

shelters than the enemy is able to target. It is

therefore necessary to estimate the number of

RVS (reentry vehicles carrying a nuclear

warhead) which the Soviets could use to attack

the MX/MPS system, and to ensure that the

number of shelters is sufficiently large. Since

the Soviets have other high-priority targets

(bomber bases, submarines in port, etc.) and

presumably want to retain a force in reserve,

the number of RVS available to attack MX

would be somewhat less, perhaps several thousand RVS less, than the total number of Soviet

RVS.

Any effort to estimate the size of and composition of future Soviet forces is highly

uncertain — U. S. intelIigence is far from

perfect, and in some cases the Soviet leaders

themselves may not yet have made key deci-
10 MX Missile Basing

sions. OTA has sought an approximation of the

threat by making a series of conservative

assumptions, most notably that the trends of

the 1970’s in the rate of Soviet development

and deployment of their ICBM force continue

through the 1980’s and the 1990’s. On this

assumption, it is estimated that the Soviets

could have 6,000 to 7,000 RVS available to attack MX/MPS by 1990, and 11,000 to 12,000

RVS available by 1995. By the year 2000,15,000

or more Soviet RVS could be aimed at an

MX/MPS deployment. This assumes that approximately 3,000 additional Soviet RVS would

be reserved for other counterforce targets,

such as Minuteman silos, and that an additional force of Soviet strategic weapons would

be allocated to attack or threaten U.S. cities,

industry, and conventional miIitary forces.

One can calculate the approximate number

of shelters needed to ensure the survival of 100

MX missiles against the projected Soviet threat

(fig. 3). For example, if we assume the 1990

threat of 7,000 RVS targeted against MX, an 85-

percent probability of RVS reaching their

targets, a deployment of 1 missile for each 23

Figure 3.— MPS Shelter Requirement

(100 Surviving Missiles)

Number of

shelters

15,300

12,500

8,250

4,600

1990

2,700 7,000 12,000 15,300

Soviet RVS targeting MX

Assumptions:

. 1 missile for every 23 shelters

● Damage expectancy 0,85

 Feasible Soviet threat growth

SOURCE Office of Technology Assessment

shelters, and no ballistic missile defense, then

this would require a deployment of 360 missiles among 8,250 shelters. Similarly for the

1995 threat of 12,000 RVS, the same survival requirement could be met with 550 MX missiles

among 12,500 shelters.

An alternative assumption is that, faced with

the threat that MX would pose to their silos,

the Soviets would devote their efforts to providing survivable basing for their existing

ICBM force, rather than to expanding their RV

inventory in order to attack MX/MPS.

The existing schedule for the baseline case

calls for completion of 4,600 shelters by 1989,

although it does involve some optimistic

assumptions. Continuation of the planned construction rate (roughly 100 shelters per month)

would mean that it would be 1992 before the

level of 8,250 shelters was approached, and by

then 8,250 could be insufficient. By 1995 the

number of shelters constructed (at a rate of

100 per month) would be just under 12,000

— still somewhat less than the number of available Soviet RVS. Clearly, a response to a Soviet

effort to overwhelm MX calls for either an

ABM system (discussed below) or a higher construction rate.

A large MPS system which was too small to

retain survivability couId stilI have some value

as a means of limiting Soviet options. It would

stilI oblige the Soviets to use a large fraction of

their strategic forces to destroy a somewhat

smaller fraction of U.S. strategic forces.

However, if the Soviets “fractionate” – i.e.,

put a larger number of smaller warheads on

their large missiles —then the Soviets might be

willing to accept an unfavorable exchange

ratio because they could “afford” to expend a

large number of RVS in order to destroy a

smaller number of RVS that constituted the entire U.S. ICBM inventory. I n any case, it is clear

that an MPS that was far too small, say half as

many shelters as available Soviet RVS, could

not be considered at al I survivable, and wouId

be of little greater value than single shelter

basing.

With the same reasoning, an MPS system

that requires a number of years to build would
Ch. l—Summary ● 1 1

not reach survival value until the number of

operational shelters exceeded the number of

Soviet RVS available to attack them, If one

assumes that the number of available Soviet

RVS may grow from year to year, then the time

when U.S. MPS construction actually began

and the rate at which shelters were constructed would both be critical. Since building

additional shelters would require time, including time to plan the additional building

program, the United States would require a

prediction several years in advance of the size

of the Soviet threat against MX.

The Air Force has estimated that a construction rate of 2,000 shelters per year (about 165

per month) would not exceed projected construction resources, although there would be

an additional $400 m i I I ion in front-end costs

(e.g., additional cement factories). Assuming

this construction rate, to start construction in

1986 would bring the United States to the required shelter level sometime in 1991, and it

might not be difficult to stay ahead thereafter.

However, it would be necessary to decide by

1983 (or 1984 at the latest) that a 2,000 shelter

per year construction rate would be needed,

and it is not clear that by 1983 the United

States will have a reliable estimate of the path

that Soviet ICBM deployment will have taken

by 1990. Furthermore, )the United States could

not first buiId a 4,600-shelter system and then

decide to expand it if it proved to be too small,

unless the United States were prepared to

defer survivability into the mid-1990’s. Therefore, the completion date, size, regional impact, and cost of an MPS system would all depend in part on what the Soviets chose to do,

and on the accuracy of the U.S. estimates of

future Soviet programs.

It is possible that the Soviet decision about

whether to attempt to overwhelm MX/MPS

with large numbers of RVS would depend on

Soviet estimates of their chances for success.

U.S. construction of MX/MPS at the baseline

rate might tempt the Soviets to deploy more

RVS in order to “stay ahead, ” while a U.S. decision to build a larger deployment at an accelerated rate might persuade the Soviets that

deploying many more RVS was pointless. In

this case, the expansion of the program would

make itself unnecessary, but the United States

wouId probably realize this only after incurring the greatly increased costs and regional

impacts of expansion

Regional Impacts

The regional impacts of the proposed MPS

basing system would be severe and could include the long-term loss of thousands of

square miles of productive range lands,

However, the severity of these impacts would

resuIt as much from the site selection criteria

as from the nature of the basing system and

could be mitigated, in part, by variants of the

proposed system.

MPS construction would require a work

force ranging in size anywhere from 25,000 to

40,000, depending on construction techniques,

program decisions, and the total number of

shelters required by 199o. The total associated

population could be as high as 250,000 people.

Because MPS siting criteria require minimum

population densities, this influx of people

wouId necessarily overwhelm the social infrastructure and severe impacts would result

within the deployment area. The overall impacts would include potential economic benefits; but experience with rapid growth

throughout the West suggests that most of

these benefits would go to in-migrants with

specialized skills, while unemployed residents

of the deployment area, women, minorities,

and Indians would be least likely to benefit. At

the same time, the economic restructuring of

the region would adversely impact many local

businesses. The cultural values of isolated

communities with integrated social structures

wouId also be subject to severe disruption.

I n the larger urban areas on the periphery of

the deployment area, MPS would have different effects. Although these areas might

have sufficient social infrastructures to absorb

rapid population growth, uncertainties regarding the potential size of the MPS related population increase and their geographic distribution would preclude effective growth manage-
12 ● MX Missile Basing

ment. As a result, investment planning in both the resource and manpower requirements conthe public and the private sectors would prob- tribute to delays in energy project schedules.

ably fail to minimize the adverse impacts or

maximize the potential benefits of MPS l-he physical impacts of MPS would necesdeployment. Finally, smaller communities af - sarlly involve the disruption of 200 square

fected by planned energy developments in sur- miles of land area for construction of shelters,

rounding areas could be impacted by MPS if roads, and support facilities (fig. 4). In a

Figure 4.— Potential Vegetative Impact Zone

SOURCE Off Ice of Technology Assessment
Ch. l—Summary ● 1 3

deployment area with moderate rainfall and

agricultural productivity, the major impacts of

construction might be confined to the loss of

those lands and related wildlife habitat, but

other lands temporarily disturbed by construction activities probably could be revegetated.

In “least productive” agricultural lands such

as the Great Basin, however, the arid environment would inhibit revegetation and effects

couId spread to adjacent lands. I n the absence

of irrigated revegetation, or if subjected to

continued disruption from PLU surveillance

activities and random off-road vehicles, these

lands would not recover. Consequently, thousands of square miles of productive rangeland

couId be desolated and the ecology of the entire region irreversibly degraded,

Institutionally, the use of Federal lands

would raise many complicated questions of

landrights, oil and gas leases, mining claims,

grazing permits, and Indian land claims, resulting primarily from potential conflicts between

PLU requirements and economic activities

such as mineral exploration and development.

If private lands are used, most of these questions could be circumvented by negotiation of

easements with explicit provisions for PLU,

definitions of compatible land uses, and

covenants regarding the resale of properties

and rights, although the process of negotiation

might delay the project schedule.

Civilian Fatalities

OTA arranged for calculations of the

number of civilian fatalities due to radiation

fallout that would result from a Soviet nuclear

attack on an MPS deployment in Utah and

Nevada. The results depend to a very large

degree on windspeed and direction, causing

calculated fatalities to range from less than 5

million to more than 20 million. However, it

seems quite probable that a Soviet nuclear attack on MX wouId be Iikely to include Minuteman and Titan missile fields, strategic bomber

bases, and submarines in port. Because these

existing targets are distributed over a large

area, the added fallout-related fatalities due to

the additional targets in the MPS fields would

have a likely range from less than 1 million to 5

million. Total fatalities for this general attack

have been estimated to range from 25 million

to 50 million people.

Fatalities due to fallout would be a major

part, but not the only measure, of damage

caused by a nuclear attack. For a discussion of

other consequences, and of the uncertainties

involved, see OTA’S earlier study, The Effects

of Nuclear War.

cost

All present cost estimates must be qualified;

apart from the usual uncertainties of estimating future costs of unprecedented programs (which means that all estimates have at

least a 10-percent error factor), there are some

design decisions that have not yet been made

that would have an impact on costs. Nevertheless, OTA reviewed the Air Force cost estimates and prepared an independent estimate

using a comparable methodology. OTA’S estimate of $37.2 billion (fiscal year 1980 dollars)

for acquisition costs of the system is within 10

percent of the Air Force estimate of $33.8

billion (fiscal year 1980 dollars) and is within

the accepted range of uncertainty. I n order to

permit fair comparison with other possible basing modes, an estimate was made for the cost

of: (a) acquisition plus (b) operating costs between initial operating capability (IOC) and

final operating capability (FOC), plus (c) the

cost of operating the full system for 10 years

after FOC. This 10-year Iifecycle cost was $43.5

billion (fiscal year 1980 dollars). Note that

neither the Air Force estimate nor the OTA

estimate includes the costs of mitigating regional impacts. The socioeconomic impacts

could amount to several billion dollars, which

would be divided in some way among the Air

Force, local and State governments, and individuals and firms in the area. The costs of irrigation to permit revegetation, if this were

undertaken, could be several billion additional

dolIars.

OTA also estimated the cost of an expanded

system. The estimated cost of a system of

8,250 shelters and 360 missiles, completed by

1990 is $62.4 billion (fiscal year 1980 dollars).
14 . MX Missile Basing

The cost of a system of 12,500 shelters and 550

missiles, completed by 1995, was estimated at

$82.6 billion (fiscal year 1980 dollars).

At the request of the Senate Appropriations

Committee, the Congressional Budget Office

(CBO) made similar estimates. Their assumptions were coordinated with OTA, but they

made use of an Air Force parametric cost

model. CBO estimates of system acquisition

costs for 325 missiles in 8,570 shelters (the least

costly mix for the 1990 threat) were $49 bilIion

(fiscal year 1980 dollars), compared to OTA’S

estimate of $52.9 billion for acquisition costs.

For the 1995 OTA projected threat, CBO estimated a system acquisition cost for 4 1 0

missiles and 13,510 shelters (the least costly

mix) of $66 bill ion (fiscal year 1980 dollars),

compared to OTA’S estimate of $71.1 billion

for acquisition costs. CBO further estimated

that if a LoADS ABM system were deployed to

meet the 1990 threat, system acquisition costs

for 225 missiles, 5,370 shelters, and 225 LoADS

defense units (the least cost mix) would be

about $44 billion (fiscal year 1980 dollars), or

about 10-percent less than an undefended system for the same threat level.

Schedule

The present Air Force schedule calls for IOC

in mid-1986, and FOC by the end of 1989. OTA

reviewed the milestones which this schedule

would require, and believes that the schedule

for IOC, while possible, is quite optimistic. Any

unforeseen delays, including delay in a firm

administration decision on MX basing mode

after July 1, 1981, would almost certainly

result in slippage in IOC. On the other hand, a

delay of some months in IOC need not lead to

a corresponding delay in FOC. Slippage in IOC

by 1 year, without significant change in FOC,

would increase acquisition costs by about $1

billion (fiscal year 1980 dollars). OTA considers

this a likely scenario.

2. MX/MPS: Vertical Shelters

There is technical disagreement over

whether MPS should have horizontal or vertical shelters. On the one hand, if missiles need

to be quickly relocated, it appears that missile

relocation takes less time with horizontal

shelters than with vertical shelters because

missile insertion for horizontal shelters is

somewhat simpler. On the other hand, the

United States has more experience with, and

understanding of, vertical shelters; and pound

for pound of concrete, vertical shelters are

more resistant to nuclear weapon effects than

horizontal shelters. As a result, less land area

might be required for a given number of

shelters. Still, it appears that with adequate

field tests, horizontal shelters could be built to

withstand the expected nuclear environment

with confidence.

There is no particular reason to believe that

PLU, arms control verifiability, or addition of

an ABM system would be significantly easier

or more difficult if a shift were made from

horizontal to vertical shelters. However, about

a year of intensive engineering development

has taken place on the basis of a decision to

use horizontal shelters. Much effort has gone

into design of PLU and ABM components, and

this effort would have to be done over. Apart

from the loss of time, real confidence in vertical shelter PLU or vertical shelter ABM would

have to await the results of this design effort.

OTA estimates that the Iifecycle costs for a

4,600 vertical shelter system with a 1989 FOC

would be reduced by about $1.5 billion (fiscal

year 1980 dolIars) if the shift were made to vertical shelters now.

3. Valley Cluster Basing

A variant of the baseline system, that has

received serious consideration within D O D

during the first part of 1981, is to replace “individual clusters” with “valley clusters. ” This

change would mean creating a single large

cluster i n each valIey, establishing the roads so

that it would be possible to move a missile between any two shelters in the same valley. This

approach is in contrast to the baseline arrangement in which only 1 missile has access to each

group of 23 shelters, and each missile can be

placed only in one of its “own” 23 shelters.

Valley clustering would not alter the design of

the missiles, shelters, or transporter trucks.
Ch. l—Summary ● 1 5

This change would have the following effects:

1. It would require fewer maintenance

facilities. Instead of 1 facility per cluster

of 23 shelters (required because the transporter trucks could not carry missiles

from one cluster to another), there could

be only one or two facilities per valley.

This would save money in both construction and operation.

2. It would require fewer transporter trucks.

Instead of one transporter per missile, it

would be possible to have one transporter

for several missiles. This would save

money, but it would mean that reshuffling

all the missiles and decoys would take

longer, and it would limit the possibility of

“dash to shelter” as a fallback mode if

PLU were broken.

3. It would have only marginal effects on

PLU.

4. It could make arms-control verification

more difficult. While it would probably

not affect the difficulty of clandestinely

introducing additional missiles into the

deployment area (i.e., putting missiles in

shelters that are supposed to contain

decoys), it would make it most difficult to

verify after the fact that such cheating

had or had not taken place. Since this

drawback is the same as the drawback of

saving money by eliminating the so-called

“SALT ports” (openable hatches in the

tops of shelters designed to facilitate

verification), valIey clusters and elimination of SALT ports (which would save

money) appear to some as an attractive

combination.

5. Valley clusters would not change the principal regional impacts.

On balance, shifting to valley clusters, if

combined with the elimination of SALT ports,

might save close to $2 billion (fiscal year 1980

dollars), at the cost of slower reshuffling and

more difficult verification.

4. Split Basing MPS: Nevada/Utah

and West Texas/New Mexico

Split basing would locate half of the shelters

in the Great Basin of Nevada and Utah, and

half in the Southern High Plains of west Texas

and New Mexico. The rationale would be to

mitigate the adverse regional impacts— both

socioeconomic and physical — by making the

deployment in each region smaller.

Split basing would mitigate some of the

adverse impacts of MPS. The mitigation would

arise from the likelihood that the rapid

changes created by MX/MPS construction

could be below thresholds where they become

difficult or impossible to manage in the

available time. However, if the baseline shelter

number (4,600) and construction rate (roughly

1,200 per year) proved inadequate, then split

basing would probably not mitigate the impacts, but might make system expansion easier

because plenty of suitable land would be

readily available. Split basing could complicate issues of land acquisition, since the

land to be used in Nevada and Utah is largely

public land, while the land in west Texas and

New Mexico is largely in private hands.

Split basing would increase the costs of both

construction and operation by about 7 to 10

percent.

5. MX/MPS With a LoADS ABM System

An alternative to increasing the number of

shelters in the face of an expanded Soviet

threat would be to provide the MPS system

with a ballistic missile defense. The Army’s

LoADS has been proposed for the role of

defending an MPS system.

The LoADS defense unit (DU) (fig. 5), consisting of a tracking radar and nuclear-armed

interceptor missiles, would be designed to fit

in the shelters and appear just like an MX

missile or a decoy to outside observers or sen-
16 . MX Missile Basing

Figure 5.— LoADS Defense Unit After Breakout

(human figure indicates scales)

SOURCE. Off Ice of Technology Assessment

sors. A DU would be hidden in each cluster of

shelters and programed to defend the shelter

containing the MX missile. The DU might also

have to defend itself. When it became apparent that a Soviet attack was on the way, the

DU would break through the top of the shelter

and prepare to fire.

The Soviets would have to target two

warheads at the shelter containing the MX

missile, since the first one would be intercepted by LoADS with high probability. Since

the Soviets would not know which shelter contained the MX, they would have to target two

RVS against each of the shelters in the cluster.

Thus, addition of LoADS to the baseline MPS

system would double the price the attacker

would have to pay to destroy an MX missile

from 23 to 46 RVS. The effect would be the

same as doubling the number of shelters while

keeping the number of missiles the same.

It is possible to have high confidence that

LoADS would exact a price of 2 RVS per shelter

if the locations of LoADS DUS and the MX

missiles could be concealed and if the DU

could be hardened to survive the effects of

nearby nuclear detonations. This confidence,

conditional upon successful deception and nuclear hardness, results both from advances in

ballistic missile defense (BMD) technology in

the last decade and from the relatively modest

goal of exacting from the Soviets one more RV

per shelter.

Successful deception would be essential for

LoADS defense, since if the Soviets found out

which shelter contained the DU, they could attack. that shelter first, force the DU to use up

all its interceptors in self-defense, and then attack. the remaining shelters using one RV per

shelter. The situation would be far worse if

detection of the DU somehow made it feasible

for the Soviets to locate the MX missile as well.

Since the DU would be a functional object–

not just a decoy that could be designed in any

way that would make it indistinguishable from
Ch. l—Summary ● 1 7

a missile to Soviet sensors— PLU would

become considerably more complex if LoADS

were added to MX/MPS, It would probably be

necessary to alter some features of the MX

missile canisters and the decoys to mimic

distinctive features of the LoADS DU. Because

of this possibility, a deferred decision to

deploy LoADS (made after the dimensions of

the future Soviet threat became clearer) would

entail more risk and cost unless the MPS

system had been designed with the LoADS addition in mind.

The LoADS DU would have to survive and

operate in a nuclear effects environment unprecedented for so complex a piece of equipment. Measures taken to protect the DU would

furthermore have to be consistent with the

severe design constraints imposed by PLU. It is

not possible to have confidence that the goals

of PLU and nuclear hardening can be met —

separately, much less simultaneously— until

detailed design and testing are done.

There is a variety of ways in which the

Soviets might respond to deployment of

LoADS, involving both special attack strategies and new weapon systems, which could

pose a threat to the defense’s effectiveness.

These so-called “reactive threats” are discussed in chapter 3 of this report and its

classified annex. The risks to LoADS’ effectiveness (in forcing the Soviets to target each

shelter twice) from these threats appear to be

moderate.

Because LoADS would be integrated into

the MPS system, the environmental impacts

would be essentialIy the same as for baseline

MX/MPS.

LoADS DUS that were mobile or that contained more than one interceptor missile per

DU could not be developed outside of the

laboratory, tested, or deployed within the

terms of the ABM Limitation Treaty reached at

SALT 1. Pursuing this option from the present

technology development stage into prototyping or deployment would require amendment

or abrogation of the Treaty. The diplomatic

and political consequences of seeking amendment or unilaterally withdrawing from the

Treaty are beyond the scope of this study.

Amendment or abrogation would give the

Soviets the legal right to develop and deploy

an ABM system of their own. A Soviet ABM

deployment might create a situation in which

the United States felt it needed more surviving

MX missiles, and hence a larger deployment, to

be sure of destroying defended Soviet targets.

6. MPS Deployment of Minuteman Ill

A related possibility would be to construct

additional silos or shelters in the existing

Minuteman I I I fields, and modify the Minuteman I I I missiles to permit them to be moved

around deceptively and concealed among the

available shelters. The rationale for such an

option would be to use the MPS concept to

make the existing Minuteman I I I missile survivable, thereby saving time and money. Such

a system might replace MX altogether, or it

might serve as a precursor system, with MX

gradually replacing Minuteman III missiles in

the new MPS field. It could also serve as an interim measure, providing survivable land basing until some other mode of MX basing was

read y.

Such a system appears to be technically

feasible. The existing Minuteman III missiles

and launch-support equipment would be cannisterized separately to facilitate movement

among protective shelters. New transporters

for the Minuteman missiles and associated

equipment would have to be procured, and

roads in the deployment area wouId have to be

upgraded. It would also be necessary to design

a system for maintaining Minuteman PLU similar to but not identical to the system of maintaining PLU for the MX. Minuteman PLU would

have similar technical risks and uncertainties,

although the institutional problems would be

altered by the predominance of private lands.

The regional impacts would be similarly

altered, and OTA’S analysis suggests that both

the range of likely impacts and the probability

of extremely severe impacts would be reduced.

It would be possible, at additional cost, to

replace the existing guidance system with the

new AlRS (advanced inertial reference sphere)
18 . MX MissileBasing

guidance system being designed for MX; this

would upgrade the military capability of Minuteman I I I to the level of the MX missile, except that since each missile would carry fewer

warheads, more missiles would be required for

an equivalent capability.

Cost and schedule are of particular interest

in considering an MPS rebasing of Minuteman

I II, since this basing mode was originally proposed as a “quick fix.” Assuming a firm decision in july 1981, it appears that Minuteman

MPS could not be deployed on a faster schedule than MX/MPS. Because of the need to replicate for Minuteman the design work already

done on PLU for MX, and the need to begin the

environmental impact statement and land acquisition processes, construction for Minuteman rebasing probably could not begin before

the spring of 1985, and FOC for a survivable

5,800-shelter Minuteman MPS system would

probably be in the spring of 1989, Cost of a

Minuteman MPS would be less than the cost of

MX/MPS, OTA estimates that Minuteman MPS

system composed of 5,800 shelters and 667

missiles, which would have roughly equivalent

survivabiIity to baseline MX/MPS and existing

silo-based Minuteman, couId be built and

operated for about $36 billion, or roughly $7

billion less than MX/MPS (fiscal year 1980

dollars). This figure would include reopening

the Minuteman production line to provide test

missiles and spares, but would not include the

cost of retrofitting the MX guidance system

(AIRS) on to the Minuteman Ill missiles. If the

systems had to be augmented (whether by expansion, by adding LoADS, or both) to meet an

expanded Soviet threat, the cost advantage of

Minuteman III MPS would diminish somewhat.

Expanding a Minuteman MPS system to

maintain survivability against an expanded

threat would require a substantial increase in

the total number of U.S. multiple independently targeted reentry vehicle ICBMS. This would

run counter to the approach to offensive arms

control which both the United States and the

Soviets have espoused during the last decade

of SALT negotiations.

7. Launch Under Attack

Another approach to MX survivability (or,

for that matter, Minuteman survivability) is to

base the missiles in fixed silos, accept the

vuInerabiIity of these siIos, and resolve to

launch the missiles before Soviet RVS could arrive to destroy them (fig. 6 gives the attack

timeline of LUA. ). Such a posture is known as

launch under attack (LUA). Adopting this approach to basing MX would mean choosing to

rely on LUA.

To have high confidence in the technical

aspects of LUA, the United States would have

to begin by substantially upgrading the systems that provide warning of an attack and

emergency communications. OTA’S analysis

indicates that providing sensors and communications I inks that were highly reliable in

the face of Soviet efforts to destroy or disrupt

them is feasible but would require time,

money, and continued effort. Almost all improvements in this area could be deployed by

the end of the decade at a cost of several

billion dollars. The total cost of this basing

mode, including the MX missiles, might be

about half that of baseline MPS. Some of the

systems required for LUA would be desirable,

or perhaps even necessary, for other basing

modes as well.

Once this were done, we could have high

confidence that LUA was technically feasible

provided that National Command Authorities

(i.e., individuals empowered to order the

launch of the MX missiles) were in communication with a command post at the moment the

Soviet attack was detected so that they could

assess its meaning, decide how to respond, and

Figure 6.— Attack Timeline

Time (minutes)

SOURCE Office of Technology Assessment.
Ch. l—Summary ● 1 9

communicate a launch order to the forces in a

short period of time. Whether the President

wouId be available at al I times for this purpose, or delegate his most awesome authority

to someone who was, is clearly not a matter of

technology but of decision at the highest level

of government.

Apart from this question, LUA has several attractive features as an MX basing mode.

Because existing silos could be modified for

use by MX missiles, there need not be any major environmental or societal impact. The cost

would be lower than for any other MX basing

mode, and deployment could take place as

soon as MX missiles were produced. LUA

would preserve familiar features of silo basing,

including weapon effectiveness as measured

by accuracy, time-on-target control, retargeting capability, and the like; familiar force

management procedures; and familiar arms

control verification procedures. The same

targets (and perhaps more) would be available

in the first few minutes of a war as in the first

few hours or days. An LUA force could therefore participate in U.S. war plans in any role

except that of a secure reserve force.

Reliance on LUA also has some serious

drawbacks. Decision time would be very short.

Depending on the circumstances, decisionmakers could lack crucial information regarding the extent and intent of the Soviet attack —

e.g., information about targets which the

Soviets had chosen not to attack. Such information could be necessary to gauge the

proper response. Decisionmakers would also

lack an interval between attack and response

during which an effort could be made to assess

intelligence information, consider diplomatic

measures, and signal the intent of the U.S.

response.

No matter how much money and ingenuity

were devoted to designing safeguards for the

U.S. capability to launch under attack, and

even if these safeguards were very robust indeed, it would never be possible to eradicate a

lingering fear that the Soviets might find some

way to sidestep them.

Finally, despite all safeguards, there would

always remain the possibility of error; depending on the nature of the error, it couId mean a

successful Soviet first strike against MX or it

couId mean a nuclear war started by accident.

8. Silo-Basing With an ABM Defense

For defending a relatively small number of

targets such as MX silos, an ABM system that

operates outside the atmosphere is preferable

in theory to a low altitude defense system. This

is because an exe-atmospheric (or “exe”)

defense could intercept many RVS headed for

a single silo, whereas after a small number of

intercepts an endo-atmospheric (“endo”) system would find further defense precluded by

the effects of its own and attacking nuclear

weapons. A combination of exo and endo — a

so-called layered defense — is an attractive

concept because the principal limitation of

each layer could be alIeviated by the presence

of the other: the exo defense would break up

the dense and structured attacks which could

otherwise overwhelm an endo defense, while

an endo defense could cope with the relatively

few enemy RVS that would almost certainly

“leak” through the exo defense.

The Army’s concept of exo defense, called

the “Overlay, “ is in the technology exploration

stage. No detailed design is available, such as

exists for LoADS. In outline, the concept consists of interceptor missiles roughly the size of

offensive missiles, equipped with infrared sensors, and carrying several kill vehicles, also

equipped with infrared sensors. The interceptors would be launched into space, where the

infrared sensors would detect approaching

RVS as warm spots against the cold background of space. The kill vehicles would be

dispatched to destroy the RVS either by colliding with them directly or by deploying a barrier of material in their path.

Because no specific system based on the

Overlay concept has been worked out, it is not

possible to analyze in detail the effectiveness

of the Overlay in various attack scenarios. It is
20 ● MX Missile Basing

clear that high efficiency would be required if

it were to be able to defend a small number of

MX missiles against a large Soviet attack.

There are at present many uncertainties about

whether the Overlay could achieve the high

performance it would require to satisfy the

needs of MX basing. These uncertainties concern both the underlying technology and the

defense system as a whole. The technical risk

associated with layered defense based on the

Overlay is therefore high–substantially higher

than the risk associated with LoADS.

In addition to uncertainties and consequent

risk associated with the Overlay, there is a potential “Achilles’ heel” in the vulnerability of

infrared sensing to decoys and other penetration aids. Unlike the LoADS radar, which could

measure the weight of approaching objects

after they entered the atmosphere, the Overlay’s infrared sensors would measure their

temperature characteristics. Lightweight decoys could be made which resembled in their

temperature characteristics the heavier RVS.

The Overlay is not a system that is developed and ready for the role of defending silobased MX. As the concept matures, it will have

to deal with the fundamental problem of decoy discrimination as welI as with the design of

a specific working system. For the moment, it

would be quite risky to rely on the Overlay, or

on layered defense, as the basis for MX basing.

As in the case of LoADS, development or

deployment of an Overlay or layered defense

would require amendment or abrogation of the

ABM Treaty reached at SALT 1.

9. Basing on Small Submarines

It would be technically feasible to build,

deploy, and logistically support a fleet of small

MX-carrying diesel-electric-powered submarines. These submarines could operate within

1,000 to 1,500 nautical miles of three bases,

located on the east and west coasts of the continental United States and on the coast of

Alaska. These submarines would be highly survivable against all existing antisubmarine

threats, and against all future antisubmarine

warfare technologies which OTA was able to

project. An alternative means of propulsion,

using inexpensive low-powered nuclear reactors, is also possible.

At present, no detailed design exists for a

submarine force specifically optimized to

have flexibility, responsiveness, and accuracy

comparable to that of the ICBM leg of the

Triad. In order to provide a basis for analyzing

the degree to which these attributes could be

achieved in a submarine-based MX, OTA has

postulated a system optimized for this purpose. The system postulated uses proven technologies and existing U.S. Navy operational

practices wherever possible, and therefore differ:; in some respects from the “SUM” concept

developed by Sidney Drell and Richard Garwin.

l-he system assessed by OTA would consist

of 51 moderate-sized diesel-electric submarines, each of which carries 4 MX missiles (fig.

7). The missiles in their capsules would be carried horizontally outside the pressure hull.

During normal operations about 28 submarines wouId be at sea at alI tiroes, whiIe the re

-

mainder would be in port for refits or overFigure 7.—Conceptual

Submarine-Launch MX Missiles

SOURCE. Off Ice of Technology Assessment
Ch. l—Summary ● 2 1

hauls, The submarines would have pressure

hull displacements comparable to those of

existing U.S. and Allied diesel-electric submarines. If an operational need arose, the submarines would have sufficient size, speed, and

endurance to operate at distances in excess of

the proposed 1,000 to 1,500 nautical miles

from bases.

Small submarine basing raises two quite different kinds of issues. The first class of issues

relates to whether or not small submarine basing is appropriate for MX; the second class of

issues are technical questions about the extent

to which such a basing mode would enable X

to meet the requirements for which it is being

designed.

Placing the MX missile on board submarines

would mean that well over half of the U.S.

strategic force of the 1990’s would be submarine-based. This wouId obviously exacerbate the problems that would develop if–

contrary to expectations —the Soviets were to

develop an antisubmarine warfare capability

that was effective against ballistic missile submarines. It would not be possible to build a

new fleet of submarines without an expansion

of U.S. submarine shipbuilding capacity. It

would be necessary for three shipyards that do

not now build submarines to learn how to do

so. Submarine construction is complex, and involves more exacting quality control than surface ship construction. Delays could occur if

the shipyards have difficulties in implementing

the necessary quality control and construction

techniques, or if the industrial base supplying

certain critical materials is not expanded fast

enough. Problems could be encountered in

recruiting and retaining enough skilled and

dedicated personnel to man such a fIeet.

There is no particular reason why the existing Minuteman force would have to be

taken out of service as soon as MX was deployed on submarines, and so the land-based

ICBM leg of U.S. strategic forces would continue to exist. (Existing plans for, and OTA

analyses of, other basing modes assume the

continued operation of Minuteman after MX

deploy merit.) However, its relative weight

would be diminished, and this could have

political significance. There is a school of

thought which holds that basing a major portion of U.S. strategic forces on U.S. soil (socalled “sovereign basing”) makes a significant

contribution to deterrence. Moreover, changing the relative weight of land- and sea-based

forces would create institutional problems for

both the Air Force and Navy.

On the other hand, submarine basing of MX

could lend an element of stability to the arms

race, since a Soviet counter would involve increasing their already high level of effort in the

apparently unpromising area of strategic antisubmarine warfare rather than increasing the

number of their nuclear weapons. Submarine

basing would be fully compatible with existing

arms control concepts and verification procedures. The technical risks would be low.

OTA’S analysis focused on those aspects of

submarine basing where it is possible to make

comparisons with other basing modes: survivability, accuracy, responsiveness (including the

effectiveness of command, control, and communications), environmental impact, cost, and

schedule.

Chapter 5 contains an extensive discussion

of the issue of submarine survivability. In brief,

OTA could find no existing technology, and no

technology believed to be on the horizon,

which offers any promise for permitting an effective Soviet attack on a fleet of small MXcarrying submarines. However, the possibility

that the Soviets may discover and deploy some

antisubmarine warfare technology which cannot be foreseen cannot be excluded. If this

were to happen, the differences between the

Trident fleet (a small number of high-speed

boats operating in an enormous deployment

area) and the MX fleet (a large number of

slower boats operating relatively close to the

United States) could make it more difficult,

and perhaps impossible, for the Soviets to

deploy an antisubmarine warfare force capable of attacking both U.S. ballistic missile submarine forces.
22 ● MX Missile Basing

“Endurance” is defined as the ability to survive for weeks and months assuming that a

system has survived for a few days. The small

submarines which OTA envisaged would have

to return to a port (or conceivably an at-sea

tender) 1 to 4 months after an attack, depending on how long each submarine had already

been at sea when the attack took place.

Submarine-based MX missiles could achieve

accuracies close or equal to the engineeringdesign requirements for the land-based MX

missile. While it appears likely that land-based

MX accuracies would exceed these requirements, submarine-based systems may well

have such high damage expectancies against

very hard targets that further improvements in

accuracy would not have military significance.

OTA could find no reason to believe that the

construction of three new submarine bases

would have environmental impacts unlike

those associated with comparable construction projects in coastal areas. In this case, the

impacts would be confined to the immediate

areas surrounding the three operating bases,

and should be manageable.

Any estimate of the cost of small submarine

basing can only be approximate, since no

detailed design exists. Acquisition cost of the

system described here is estimated to be about

$32 billion (fiscal year 1980 dollars), with

another $7 billion to operate the system until

2000.

Construction of submarines is a complex

and specialized task, involving rigorous quality control and specialized materials not normally required for shipbuilding. At present

there are only two shipyards in the United

States capable of building submarines, and

both are backlogged. Bringing additional shipyards to the point where they could build submarines, and obtaining the necessary parts and

materials, could perhaps involve substantial

delays. OTA estimates that the first such submarine could not be operational before 1988

at the very earliest, with 1990 a more realistic

date. Four more years would be needed before

the force reached the number of 51. Efforts to

accelerate this schedule (or, if things went

wrong, to maintain this schedule) could delay

other, existing submarine construction programs. However, the first MX missiles deployed on small submarines would be highly

survivable, in contrast to other basing modes

which would attain survivability only after

most or al I of the force was operational.

10. Surface Ship Mobile

Another approach to seeking survival by

mobility at sea is to base the MX missiIes on a

fleet of surface ships. Such a fleet would be

designed to have an appearance similar to

merchant shipping, and to hide itself either in

broad expanses of the ocean or among the

other ships in crowded shipping lanes. The

techniques for lowering missiles over the side

of a ship and launching them from the water

are well-established, although other launching

modes might prove preferable.

Most of the points noted in the previous section about shifting the weight of U.S. strategic

forces from land to sea apply. Unlike submarines, the surface ships wouId have a security

problem in making certain that third parties

did not attempt to seize the MX missiles. The

ships would have to have a considerable capability for self-defense. The need for defensive

weaponry could make it more difficult to disguise the ships.

An examination of the way in which such a

force of surface ships might operate reveals

numerous operational problems, which interact with the task of assuring survivability.

Briefly, the Soviets could destroy any MXcarrying surface ship which they could locate

or, having located, trail. OTA’S analysis (ch. 7)

assumes that by the 1990’s the Soviets would

deploy a large force whose purpose was to

locate and trail such ships, and finds that in

such a case the proportion of a fleet of such

ships which would be located and under trail

might fluctuate greatly from day to day.

Hence, although attacking such ships would be

a formidable task for the Soviets, the United

States could not have confidence in the survivabiIity of surface-ship mobile MX.
Ch. l—Summary ● 2 3

While cost and schedule estimates cannot

be precise for a system that has never been

designed in detail, it is estimated that surfaceship acquisition costs would be comparable to

those of a fleet of small submarines. Annual

operating costs would be SIightly higher than

those of small submarines. These differences

are within the range of expected error A surface ship fleet might be operational a year or

two before a submarine fleet. Given the

greater survivability of submarine basing, it

would seem to be preferable to surface ship

basing if sea mobile basing is chosen.

11. Air Mobile

Air mobile MX would be a system of great

operational complexity, and therefore there is

a corresponding wide choice of specific concepts. The lowest cost concept would consist

of 75 or so wide-bodied aircraft, each carrying

two MX missiles, maintained on strip alert at

airfields located in the Central United States.

Such a “dash-on-warning” air mobile force

could be highly survivable. The principal

threat to the force would be submarineIaunched ballistic missiles (S LBMS) launched

from positions near U.S. coasts. Such an attack

could arrive in the vicinity of the alert airfields

within 15 minutes of launch and seek to destroy the aircraft before they could take off

and escape. However, if a high-alert posture

were accepted for the force, meaning that the

aircraft took off immediate/y upon time/y

warning of SLBM attack, almost the whole

force would survive even if a large number of

SLBMS were launched from positions near U.S.

coasts (see fig 8). The Soviet SLBM force is

presently incapable of such an attack. Airmobile basing could therefore stress Soviet

strategic forces where they wouId be least able

to respond in the short term.

Nevertheless, the difference between survival and destruction of the force would be a

very few minutes, depending on timely tactical

warning. I n this respect an air mobile ICBM

force would replicate a significant failure

mode of another leg of the strategic Triad —

the bomber force.

Figure 8.—Survivability v. Escape Time

(8 EMT on Each Airstrip, 2 PSI Aircraft)

100,

)

80

60

I

. .

40 —

20 —

o I 1 I I t I

0 1 2 3 4 5 6 7 8 9 10 11 12

Aircraft escape time before arrival of SLBM attack (minutes)

SOURCE Off Ice of Technology Assessment

ICBMS, arriving later than the SLBMS, could

not threaten the survivability of the force as a

whole, since by that time the aircraft would

have been in flight long enough to be dispersed

over a wide area. Effective barrage attack of

this area would require the Soviets to build

many more large IC BM missiles than they now

possess and use them to barrage a m i I I ion or so

square miles. The outcome of such an attack

would be insensitive to both the fractionation

(the apportioning of the missile payload

among a small number of Iarge-yieldt[ge-yield RVS or a

larger number of smaller yield RVS) and to the

accuracy of Soviet ICBM forces.

The principal disadvantage of a dash-onwarning force—the need for reliable, timely

warning—could in principle be removed by

having the aircraft maintain continuous airborne patrol. However, even with a new aircraft designed for low fuel consumption, the

cost of operating such a force would be prohibitive. A continuously airborne force of 75

aircraft (1 50 MX missiles) couId cost $80 biIIion

to $100 billion (fiscal year 1980 dollars) to acquire and to operate for 10 years after full

deployment (FOC).

A second crucial problem for an air mobile

force concerns the question of postattack endurance. After a few hours of flight, the aircraft would have to land and refuel. Since their

home airfields would be destroyed, they would
24 ● MX Missile Basing

have to find other places to land and await further instructions. This problem could be

avoided completely if the United States were

willing to adopt a policy of “use it or lose it”

for the few hours of unrefueled flight. There

are also several hundred civilian and military

airfields in the United States capable of servicing large aircraft. Many of these airfields are

located close to urban areas. If the Soviets

wished to deny postattack endurance to an

air mobile fleet—tantamount to forcing the

United States to “use it or lose it” –they would

have to attack these airfields. A serious effort

to build more austere recovery airstrips

throughout the country than the Soviets possessed ICBM RVS to destroy them would be

enormously expensive, would have substantial

environmental impact, and would be completely impractical if the Soviet threat grew

large. For instance, 4,600 airfields spaced 25

miles apart would fill the entire 3 million

square miles of the continental United States.

There could conceivably be some value in

having more airfields suitable for air mobile

operations than the Soviets had SLBM RVS.

These could be useful if the United States

doubted the reliability of its SLBM warning

sensors and wished to relax the force’s alert

posture (since, in a crisis, false-alarm takeoff

might be mistake~ by the Soviets for preparation to launch the MX missiles), or if the fleet

were somehow “spoofed” into taking off (thus

making a portion vulnerable as the aircraft

were forced to land). A force with this dispersal

option could cost $10 billion to $20 billion

(fiscal year 1980 dollars) more than a widebodied jet force with no recovery airfields

beyond existing large civilian and military airfields.

Thus, the lowest cost air mobile system

would exclude extra recovery airfields beyond

those large civilian and military airfields which

exist at present. Although OTA has not performed detailed cost and schedule analysis for

such an air mobile option, it appears that the

cost of a force with 75 aircraft (150 MX missiles) on alert would be comparable to the cost

of the baseline MPS system and could be deployed in a comparable time.

An air mobile force would also require several supporting systems. First and foremost

would be reliable sensor systems for timely

warning of Soviet attack. Providing such systems would be technically feasible but would

require time, money, and continued effort. The

complex force management needs of the air

mobile force after attack would require a

comparably complex communications system.

Last, providing for missile accuracy comparable to land basing would require use of the

Global Positioning Satellite system or a

Ground Beacon System.

COMPARISON OF BASING

MODES

As we have indicated above, OTA’S technical analysis of MX basing modes does not support a clear or simple choice, All of the basing

modes reviewed have strengths and weaknesses. This section presents the criteria OTA

has identified for the purpose of analysis, and

uses them to compare the five most feasible

options. Since no basing mode ranks high

against all criteria, choosing among them depends on the relative weight attached to each.

Technical Risk

Technical risk refers to the level of confidence that one can have at this time that the

system will perform the way it is supposed to.

There are significant risks associated with

two of the five basing modes considered. PLU

will represent an area of significant technical

risk for MPS basing until prototypes have been

tested, and could be a subject of lingering

doubts even afterwards. The use of LoADS

with MPS would compound this risk. An additional technical risk for LoADS concerns the

requirement that LoADS operate in a nuclear

environment of unprecedented severity, inducting high-yield nuclear donations roughly a

miIe away.

The risks of LUA arise not from technically

difficult problems, but from the uncertainties

of the interface between men and machines.
..Ch. l—Summary ● 25

Survivability y

A force is “survivable” if its destruction by a

Soviet first strike is infeasible, Some basing

modes aim at protecting the entire force while

others accept some attrition and size the system to assure an adequate number of survivors Survivability would be of critical importance to deterrence in either of two scenarios.

The first is that the Soviets considered an allout war inevitable, and were considering

whether striking first would Iimit the damage

such a war would cause to the Soviet Union.

The second is that the Soviets sought to control the outcome of a crisis by partialIy disarming the United States while deterring the

United States from responding. In either case,

it wouId be important that the United States

could feel confident that the Soviets would

doubt their ability to destroy a relatively large

proportion of U S. strategic feces All the MX

basing modes are designed to provide this

assurance, but they do so in different ways. For

this reason, they create somewhat different

risks,

A timely decision to launch under attack

wouId prevent the Soviets from destroying the

missiles before they were used Air mobile MX

would become vulnerable if the United States

failed to receive and act on adequate warning,

a faiIure mode which it wouId share with the

bomber leg of the Triad. The MPS systems (including the MPS/LoADS combination) would

become vulnerable if PLU broke down, and

wou Id a I so become vu I nerable whenever the

size of the MPS system was too smalI relative

to the Soviet threat. This latter occurrence is

not so much a question of technology as it is a

question of the judgment and optimism of U. S

policy makers: a rapid growth in the Soviet

threat could make MPS vulnerable unless the

United States had decided to expand the system before Soviet intentions had become

clear. Small submarines do not appear to be

vulnerable, either now or in the foreseeable

future, However, if an unforeseen Soviet

breakthrough in antisubmarine warfare occurred, it is possible that it would threaten

both small submarines and the Trident/Poseidon leg of the Triad.

LUA would become progressively less vulnerable as improved warning and communications systems were brought online. MPS (with

or without LoADS) wouId become Survivable

onIy after the n u mber of shelters deployed Surpassed the number of Soviet RVS available to

attack them Small submarines. would be

highly survivable when first deployed

Endurance

En

survive

and

durance is defined as the capabil

 as an integrated system — both m

the communications needed to

them — for an extended period after a nuclear

ty to

ss i Ies

use

attack, assuming that the system survives the

attack itself. An LUA system wouId clearly

have no endurance,

An air mobile system would not endure

longer than 5 to 8 hours unless the Soviets

chose not to attack the airfields at which the

MX-carrying aircraft could land and refuel.

LoADS could be ineffective against a second

attack. SmaII submarines with diesel-electric

propuIsion wou Id endure from 1 to 4 months at

sea, and longer if provisions were made for

replenishment N u c I ea r-e I ect r i c propu Is ion

couId provide longer endurance for smalI submarines. MX,’ M PS is designed to endure i n a

low-power mode for many months after an attack.

Weapon Effectiveness

This criterion addresses the question of how

well MX in the various basing modes could

support those aspects of U.S, nuclear weapons

employment policy which have previously

been the specialty of the ICBM leg of the

Triad, including ability to destroy hardened

Soviet targets (accuracy and time-on-target

control), strike rapidly on command (responsiveness), and support a doctrine of flexible

response (retargeting capability),

Land-based systems (MPS, MPS with LoADS,

and LUA) will continue to set the standard for

accuracy, time-on-target control, responsiveness, and rapid retargeting. MX based on small

submarines would be almost as good, and in-
deed would most probably be close to or equal

the design requirements for MX. There would

be few if any military missions of importance

for which a submarine-based MX (given feasible upgrades in guidance systems, navigational

aids, and C J systems) would be significantly

less capable than land-based MX. Air mobile

basing would sacrifice a degree of responsiveness because of the need for the aircraft to

takeoff before launching the missiles, would

require external navigation aids to achieve

high accuracy, and management of a dispersed

air mobile force could be very complex.

Command, Control, and

Communications (C3

)

Reliable communications impervious to

Soviet attempts at disruption are needed for

commanders to assess the status of the MX

force, retarget the missiles if desired, and

transmit launch commands. The technical

means to accomplish these tasks, as well as the

tasks themselves, couId be very different in the

preattack, transattack, and postattack periods.

There are distinct and important differences

from basing mode to basing mode regarding

both the technical means to support effective

C

3 and potential vulnerabilities. In each case,

it appears that with adequate funding and effort, acceptable technical solutions are available, though it would be extremely difficult to

secure any C3 system against any and all contingencies. On balance, OTA has found no

clear technical reason for preference among

the basing modes on the basis of C3

.

Arms Control Considerations

The choice of basing mode could affect

arms control in several ways. First there is the

question of whether a given basing mode conflicts with U.S. obligations under a treaty now

in force. Also of interest are possible conflicts

with treaties signed but not ratified. Apart

from specific treaty provisions, the United

States has a longstanding policy that strategic

systems should be amenable to verification.

The impacts of MX basing on future arms control negotiation are speculative. They involve

not only the negotiability of future arms control agreements, but also incentives which

might be created for increasing or reducing the

level of strategic armaments.

Deployment of a LoADS ABM system in

defense of MPS would require amendment of,

or U.S. withdrawal from, the ABM Treaty

reached at SALT 1, though much predeploy -

ment work could be done within the terms of

the Treaty. In general, the five basing modes

we are comparing appear compatible with the

provisions of SALT 11. MX/MPS has been

designed specifically to be compatible with

this proposed Treaty.

A future arms control agreement that permitted MPS basing but Iimited the number of

missiles could be verified if the system were

designed from the outset with this in mind. An

agreement permitting the deployment of the

MX missile on small submarines or aircraft

CouId be verified using established procedures

and nationaI technical means.

MPS basing could complicate future arms

control negotiations. Detailed understandings

about deployment procedures and peacetime

operations, not previously included in arms

control agreements, could be required for the

United States to verify limits on a Soviet MPS

deployment. Because MPS deployments must

be large in order to be survivable, MPS basing

CouId tend to provide incentives for continuing increases in numbers of strategic arms, and

comlicate efforts to seek agreements Iimiting

or reducing these numbers. Moreover, MPS

would necessariIy focus attention on numbers

of RVS.

Institutional Constraints

The Navy has shown little interest in small

submarine basing of MX, and the Air Force opposes it. The LoADS ABM concept would not

challenge existIng roles and missions, but it

wouId require early and close Army/Air Force

cooperation, MX/MPS would strain the ability

of Federal, State, and local jurisdictions to

plan and coordinate adequate provision of

social services and environmental protection.
0Ch l—Summary ● 2 7

Impacts on the Physical Environment

MPS systems would have considerably

greater physical impacts than the other basing

modes considered In the Great Basin of

Nevada and Utah these impacts would be particuIarly severe and could include the longterm loss of thousands of square miles of productive rangelands. Although the qualitative

impacts of both split basing and Minuteman

MPS would be essentialIy the same, the magnitude of these impacts would be significantly

reduced by split basing and couId be reduced

further by basing in the northern Minuteman

fields Impacts of air mobiIe basing wouId re

suIt from airfield construction, but severe impacts would be unlikely The impacts of submarine basing would be site-specific and confined to the areas where operating bases would

be built, but could be significant within these

areas The i m pacts of LUA as a basing mode

would be minimal

Socioeconomic Impacts

The magnitude of MPS construction would

have major impacts on the socioeconomic

structure of any deployment area selected on

the basis of minimum popuIation criteria Furthermore, uncertainties regarding the size and

the distribution of the work force population

would make advance planning so difficult that

effective mitigation of adverse impacts would

be unlikely These impacts would be most

severe in the case of MPS in Nevada and Utah,

but would also accompany split basing or

rebasing of Minuteman I I I

The impacts of air mobiIe and submarine

basing would be confined to the areas where

operating bases were built, and might be

positive or negative depending on the characteristics of the areas chosen

no impact

costs

OTA has compared costs

LUA wouId have

on the basis of

“lifecycle” cost, which includes both the cost

of acquiring the system and the cost of opera ting it untiI 2000

The baseline MX MPS system of 200” missiIes

and 4,600 shelters was sized to provide adequate survivability against a particular Soviet

threat For costing purposes OTA has sized the

other systems to provide equivalent survivability against a comparable threat. If the

Soviet threat should grow, MPS systems (including MX defended by Lo ADS and Minuteman,MPS) would have to grow accordingly.

Submarine basing, air mobiIe basing, and

reliance on LUA would not

Table 1 summarizes OI” A cost estimates for

the basing systems The lifecycle cost o f

baseline MPS (4,600 shelters with 200” missiles),

Table 1 .—Summary, Lifecycle Cost Estimates for Basing Options

(billions of fiscal year 1980 dollars)

MX/MPS MX/MpS

MX/MPS expanded expande d

baseline 1990 threat 1995 threat

Number of shelters 4,600 8,250 12,500

IOC/ FOC (calendar year’)” 87/89 87189 87194

Number of deployed

missile s 200 359 544

MX/M PS

vertical MXIMPS SmalI MM Ill

shelters spilt basing submarin e MPS

4,600 4,600 51* 5,800

87/89 87/89 89/95 87/90

200 200 204 667

Developmen t $ 9172 $ 9.372 $ 9.572 $ 9.172 $ 9.172 $ 7.225 $ 2.527

Investment . 27999 43,557 61.512 26.500 30109 24862 28,037

Total acquisition ... $37171 $52.929 $71.084 $35.672 $39,281 $32.087 $30.564

Operating and support

to year 200 0 $ 6.308 $ 9482 $11486 $ 6.308 $ 6.526 $ 7160 $ 5907

Lifecycle cost to 2000 $43479 $62411 $82570 $41.980 $45807 $39247 $36471

MM Ill

expande d

1990 threat

10,400

87/91

900

$ 2500

43200

$45700

$ 7.700

$53400

MM Ill

expande d

1995 threat

15,50 0

87/94

1,100

$ 2.500

60400

$62.900

$ 9500

$72400

‘Submarines

SOURCE Of office of Technology Assessment
smalI submarines, and air mobiIe are aII about

$40 billion (fiscal year 1980 dollars) OTA

estimates that split basing wouId cost about 7

percent more. Rebasing Minuteman I I I would

be about $7 billion less expensive than the

baseline MX/MPS systems LUA would be considerabIy Iess expensive than the others, even

after very SU stantial upgrading of warning

and communications systems.

Against an increased Soviet threat, the cost

of MPS would grow. If the Soviets devoted

substantial effort to threaten MPS, and if the

U.S. response was to increase the number of

shelters and missiles, then the Iifecycle cost to

the year 2000 of $43 billion for the baseline

system (OTA estimate in fiscal year 1980

dollars) might have to grow to $58 billion to

$62 billion by 1990 and to $78 billion to $83

billion by 1995. Adding LoADS instead of increasing the number of shelters could cut

costs: a Congressional Budget Office study

estimates that using an optimal mix of LoADS,

additional shelters, and additional missiles

would save about 10 percent against the 1990

threat and about 18 percent against the 1995

threat.

Note that efforts to make the survivability

of air mobile independent of warning by

means of airborne alert, or to give air mobile

some endurance by building additional dispersal airfields, wouId drive its cost u p very sharply.

Schedule

The advocates of each of these basing

modes project initial operating capabilities in

the mid- to late 1980’s. These projections are

based on rather optimistic assumptions, and

the record of U.S. development of weapon systems in the recent past suggests that schedule

SIippages are Iikely.

In considering schedule it is necessary to

distinguish among three dates for each possible basing mode.

1. Initial operating capability (IOC) refers to

the date at which the first missiles would

enter the active strategic force This date is

sign if i cant from the viewpoint of the overalI

strategic balance, and concern with how

perceptions of this balance may affect U S.

diplomac y

FUI I operating capability (FOC-) refers to the

d a t e when t h e I as t miss iles a n d bassing facilities would become active

Survivability refers to the date when the

deployed system is judged to be adequately

survivable against the then-existing Soviet

threat. This date is significant from the viewpoint of reversing the effects of the growing

Soviet capability to destroy the Minuteman

force in a first strike.

Depending on the basing mode and the growth

in the Soviet threat, survivability could coincide with IOC, could coincide with FOC, or

couId come at a date between them.

Because considerable engineering development has been accomplished for MX/MPS, it

could probably achieve IOC in 1987. Minuteman MPS could not have an IOC before 1986,

even though the missiles already exist, because

of the need for an environmental impact statement, site selection, land acquisition, and the

need to design a PLU system before starting

construction. FOC dates for MPS systems

would depend on the size of the Soviet threat.

Reasonable FOC dates are 1989 or 1990 if 200

missiles and 4,600 shelters prove to be enough,

and a Minuteman MPS of comparable size

C Ould be completed at about the same time.

So long as the threat kept growing, the system

could never be completed in the sense that

costruction could stop. However, survivabiIty could be achieved before Soviet threat

growth and U.S. construction stopped, For example, a 1990 threat of 7,000 Soviet RVS cou Id

be met by an MX/MPS system of some 8,250

shelters and 360 missiles. These could be completed by 1990 provided that a firm decision to

build at that rate were made in late 1982 or

ealrly 1983— before firm evidence of Soviet

building plans is likely to be available. To retain survivability after 1990 would require a

building program that kept pace with any continuing growth in the Soviet threat.
Ch l—Summary 29

LUA could begin, in principle, as soon as MX

m i ssiles could deployed, but upgraded

warning and communication systems might

not be developed until the end of the decade.

Adding LoADS to MPS would probably not

affeet FOC significant I y Submarine-based MX

IOC could be as early as 1988, but 1990 seems

more Iikely. An FOC for submarines appears

achievable as early as 1992, but OTA believes

that 1994 would be more realistic However,

since submarine basing wouId achieve survivability at the IOC date rather than the FOC

date, submarine basing might well achieve survivability sooner than any of the other basing

modes despite the fact that its IOC could well

be the latest

While OTA has not performed schedule

analyses for air mobiIe, it appears

mobiIe system might also be deplo

end of the decade

Stability

MX basing could affect stability

that an air

yed by the

n three dif -

ferent senses In the first, survivability (which is

treated separately above) enhances stability by

avoiding a situation in which the Soviets might

start a war because they expected to obtain an

advantage by destroying vulnerable U.S.

forces. Second, MX basing should, if possible,

minimize the risks that a war might start

because of accident or miscalculation during a

crisis. Finally, MX basing could affect the incentives which shape future nuclear weapon

deployment decisions: this is called arms race

stabi I it y

MPS basing introduces the prospect of an increasing number of U S. shelters and missiles

in response to an increasing number of Soviet

RVS. From the U.S. point of view, keeping pace

with a growing Soviet threat could be costly

and would put a premium on determining and

projecting the number of Soviet RVS For their

part, the Soviets would be tempted to expand

their RV inventory, taking advantage of their

existing throwweight to overwhelm the U.S.

MPS deployment On the other hand, the

Soviets would be concerned about the effects

of a growing MX deployment on the survivability of their own ICBMS.

LoADS ABM deployment could permit an

MPS deployment to attain survivability against

a given threat level with a smaller number of

MX missiles; in this sense it would contribute

to arms race stability. On the other hand, it

could reopen the qualitative arms race in ABM

technologies and offensive penetration techniques (including larger numbers of offensive

weapons) which the 1972 A BM Limitation ion

Treaty sought to foreclose,

SmalI submarine basing would be survivable

and might force the Soviets to redirect their efforts from building offensive weapons to intensify antisubmarine warfare research. Since

strategic antisubmarine warfare appears very

unpromising, this would be stabilizing. However, if the Soviets did achieve an antisubmarine warfare “breakthrough,” it would be

highly destabilizing.

LUA poses the risk of failure during peacetime or during crisis which could lead to accidental war. U. S deployment of a new missile

in a nonsurvivable basing mode could also

create a Soviet perception that in a crisis the

United States might choose to strike first

rather than wait to launch under attack.

Air mobile would be survivable and would

therefore not create incentives for the Soviets

to expand their ICBM force. However, its dependence on timely warning could create tension in a crisis.
Chapter 2

MULTIPLE PROTECTIVE SHELTERS

Chapter 2.— MULTIPLE PROTECTIVE SHELTERS

Page

Overview 33

Theory of Multiple Protective Shelters, 34

Preservation of Location Uncertainty, 35

Sizing the MPS System 40

Weapon Characteristics for MPS ., 44

The Air Force Baseline 45

System Description. 45

SALT Monitoring Operations 58

Siting Criteria 59

Roads 61

Physical Security System 61

Land Use Requirements 64

Water Availability 67

Physical Impacts. 68

Socioeconomic Impacts 73

Regional Energy Development . . 81

System Schedule. 82

System Cost 84

Cost and Schedule of Expanding the

MX/MPS . . ., 86

Split Basing 89

Vertical Shelters 92

Shelter Hardness. 92

Missile Mobilit y 9 3

PLU . . . . . 94

costs. . . 94

Arms Control. ,, 96

Page

Some Previous MX/MPS Basing Modes. 97

The Road able Transporter-ErectorLauncher . . . . . . . . . . . . . . . . . 97

The Trench . . . . . . . 99

Minuteman MPS and Northern Plains

Basing ,, . ......101

Missile Modifications 101

Cost and Schedule ,. 102

Civilian Fatalities From a Counterforce

MPS Strike .. 103

LIST OF TABLES

Table No Page

2.

3.

4,

5.

6.

7.

8.

9.

10.

11.

Physic Signatures of Missile

MPS Example . . . . . .

Monitoring Timeline

Principal Exclusion/Avoidance Criteria

Used During Screening .

Candidate Areas . .

Water Required for MX .

Water Uses. . . . . . . . .

Cost Overruns in Large-Scale Projects

Estimated and Actual Construction

Work Forces for Coal-Fired

Powerplants .. . . .

System Time Schedul e

36

42

59

59

61

68

68

77

78

83
Table No. Page

12. Air Force Baseline Estimate 4,600

Shelters . . . . . . . . . . . . . . . . . 84

13. Comparison of Air Force and OTA Cost

Estimates ....... . . . . . . . . 86

14. Land Use Requirements . . . . . . . . . 87

15, FuIl-ScaIe Operations. . . . . . . . . . . . . 88

16. Lifecycle Cost of 4,600, 8,250, and

12,500 Shelters to the Year 2005 . . . . . . 88

17. Air Force Estimates of Additional Split

Basing Costs. . . 90

18, Lifecycle Costs for Horizontal and

Vertical Shelters Deployed in

Nevada-Utah . . . . . . . . . . . . . . . 97

19. Minuteman MPS Costs. . . . . . . . . . .102

LIST OF FIGURES

Figure No. Page

9. Multiple Protective Shelters. . . 33

10. Preservation of Location Uncertainty

and System Design . . . 39

11. Peak Overpressure From l-MT Burst . . 40

12. Surviving Missiles v. Threat Growth

for MPS Example . . . . . . . . . . . . . . . . . 42

13. MPS Shelter Requirement for

Projected Soviet Force Levels . . 44

14. System Description . 46

15. Launcher . . 47

16. Missile Launch Sequence. . . . . . . 47

17. Cannister Construction . . 48

18. MX Protective Shelter Site 49

19. MX Protective Shelter . . . . . . . 50

20. Transporter . . . . . . . . . . . . . . . 50

21. Missile Launcher and Simulator—

Transfer Operations. . . . . . . 51

22. Mass Simulator and Launcher

Exchanges . . . . . . . . . 51

23. Mass Simulator . . . . . . . . . 52

24. Cluster Layout . . . . . . . . . . . . . . . . . . . 52

25. Shelter and Road Layout . . . . . . . . . . . 53

26. Command, Control, and

Communications System . . . . . . . . . . 54

27. Electrical Power Distribution. . . . 55

28. MX-Cannister/Missile Launch Sequence 56

29. Transporter Rapid Relocation Timeline 57

30. Dash Timeline . . . . . . . 58

31. Geotechnically Suitable Lands. . . . . . . 60

32, Road Construction Profiles . . . . . . . . 62

33, Area Security . . . . . . . . . 63

34, Point Security. . . . . . 63

35. Hypothetical MPS Clusters in

Candidate Area . . . . . . . 65

36. Potential Vegetative Impact Zone. . . . 71

Figure No. Page

37. Construction Work Force, Operating

Personnel, and Secondary Populations. 75

38. Baseline Work Force Estimates 76

39. Comparison of Onsite and Total

Construction Work Force. . . . . . 77

40. Construction Work Force: High-Range

Projection . . . . . . . . . . . . . . . 78

41. Range of Secondary Population

Growth. . . . . . . . . . . . . . . . . . . . . . . . 79

42. Range of Potential Population

Growth . . . . . . . . . . . . . . . 80

43. Cumulative Energy Activity

in the West . . . . . 82

44. proposed Split Basing Deployment

Areas . . . . . . . . . . . . . 89

45. Summary Comparison of Long-Term

Impact Significance Between the

Proposed Action and Split Basing . . 91

46. Vertical Shelter . . . 92

47. Transporter for Vertical Shelter . 94

48. Remove/Install Timelines for

Horizontal and Vertical Shelters . 95

49. Dash Timeline for Horizontal Shelter. . 96

50. Readable Transporter-ErectorLauncher . . . . 98

51. Trench Layout . . . . . . . . 99

52. MX Trench Concepts . .............100

53. Minuteman/MPS Schedule. . . .102

54A. Population Subject to Fallout v.

Wind Direction (Range: 500 rim). .. ..103

54B. Population Subject to Fallout v.

Wind Direction (Range: 1,000 nm) .. .104

54C. Population Subject to Fallout v.

Wind Direction (Range: 1,500 nm) .. .104

54D. Population Subject to Fallout V.

Wind Direction (Range: 2,000 nm) .. .104

55. Downwind Distance v, Total Dose .. .105

56. Crosswind Distance v. Total Dose .. .105

57A. MX in Texas and New Mexico:

Population Subject to Fallout v.

Wind Direction (Range: 500 rim). .. ..106

57B. MX in Texas and New Mexico:

Population Subject to Fallout v.

Wind Direction (Range: 1,000 nm) .. .106

57C. MX in Texas and New Mexico:

Population Subject to Fallout v.

Wind Direction (Range 1,500 nm). .. 106

57D. MX in Texas and New Mexico:

Population Subject to Fallout v.

Wind Direction (Range 2,000 nm). .. 107

58A. Downwind Distance v. Total Dose —

500 KT . . . . . . . . . . . . . . ........107

58B. Downwind Distance v. Total Dose—

250 KT . . . . . . . . . . . . . . . . . . . .. 107
Chapter 2

MULTIPLE PROTECTIVE SHELTERS

OVERVIEW

The multiple protective shelter (MPS) concept seeks to maintain the capabilities of a

fixed land-based ICBM force, while protecting

the force from Soviet attack, by hiding the m issiles among a much larger number of missile

shelters (see fig. 9). If the attacker does not

know which shelters contain the missiles, all

the shelters must be attacked to ensure the

destruction of the entire missile force Thus,

the logic of MPS is to build more shelters than

the enemy can successfully attack, or at least

to make such an attack unattractive by requiring the attacker to devote a large number of

weapons to attack a relatively smalIer force.

In this chapter, the theory, design requirements, and some of the outstanding issues of

MPS are addressed I n particular, the technical

and operational requirements of hiding the

missiIes among the shelters, forma I I y known as

preservation of location uncertainty (PLU), are

examined This wouId be a new task for missiIe

land basing, and it is now appreciated as one

of the more challenging aspects of MPS. The

compatibiIity of the missiIes’ location uncertainty with arms control monitoring is also discussed

Figure 9.— Multiple Protective Shelters (MPS)

SOURCE Off Ice of Technology Assessment

Inherent in the strategy of MPS is that the

number of shelters constructed be keyed to the

size of the Soviet threat. Growth i n the number

of accurate Soviet warheads wouId require a

larger deployment of missile shelters to maintain the same expected survival rate for U.S

missiIes. The sensitivity of missiIe survival and

shelter number to the size of the Soviet threat

is discussed by performing severaI MPS calculations related to possible Soviet growth

The consequences of an “undersized” MPS are

a I so exam i ned, and shelter number requirements are calcuIated.

These issues, keeping the missiles successfuIIy hidden and determining the proper

size of the MPS, are common to any MPSbasing mode, and are analyzed in detail in the

section on the theory of MPS.

Much of this chapter is devoted to specific

designs for an MPS, with a great deal of attention devoted to the Air Force’s baseline system. This system has been in full-scale engineering development since September 1979,

and was modified in the spring of 1980 to incIude a horizontaI loading dock configuration

for the missile shelter. As proposed, the

baseline system consists of 200 MX missiles

among 4,600 concrete shelters, with each m issile deployed in a closed cluster of 23 shelters.

These shelters would be spaced about 1 mile

apart and arranged in a linear grid pattern.

Each shelter would resemble a garage, or

loading dock, into which a missile could be inserted horizontally. Missile location uncertainty would rely on the use of specially designed

missile decoys of similar, though not identical,

physical characteristics to the real missile, and

the employment of operational procedures

that would treat missile and decoy alike. Large

transport trucks could shuffle missiles and

decoys among the shelters in order to keep the

precise location of the missiles unknown to

outside observers. Descriptions are provided

of the Iayout and operation of this basing, m is33
34 ● MX Missile Basing

sile mobility and the “dash” option, command,

control, and communications (C3), and estimates for system cost and schedule Air Force

criteria used for siting the MX, and its regional

impacts are also addressed.

In the discussion of regional impacts, emphasis has been on two particular issues. Because the A i r Force has aIready completed extensive studies and has published almost so

volumes of materiaIs (MX: Milestone II, Final

Environmental impact Statement; Deployment

Area Selection and Land Withdrawal A cquisition, Draft Environmentl Impact Statement;

and MX: Environmental Technical Reports)

relating to the environmental impacts of MX/

MPS basing, no attempt has been made to

catalog the potential environmental impacts,

to evaluate independently all of those impacts

identified by the Air Force, or to critique the

Air Force environmental impact statements

(EISs), Instead, those documents have been

used as resources, and attempts have been

made to draw attention to those issues that are

believed to be of most importance to the congressional decision making process, For more

detailed information on particular impacts

associated with MPS, reference should be

made to the Air Force E I S documents and comments by the States of Nevada and Utah.

A variation of the proposed system would be

split basing, where the system would be deployed in two noncontiguous regions of the

country: the Great Basin area of Utah and

Nevada, and the border region between Texas

and New Mexico, This basing scheme would

mitigate the regional impacts, at some addition to system cost.

In addition to discussions of the Air Force

baseline system and split basing, several alternative MPS designs are examined. All of these

have been studied in the past, but rejected by

the Air Force for various reasons. These designs incIude housing the MX missiIe in conventional Minuteman- like vertical shelters,

rather than the horizontaI shelters of the A i r

Force basel inc. Greater hardness against nuclear attack could be achieved with vertical

shelters; however, missile mobility would be

somewhat simpler with horizontal shelters.

Two previous baseline modes for the MX are

also) discussed: the “trench” design, where the

missile wouId reside in a long concrete-hardened tunnel several feet underground, and the

so-called “roadable TEl,” the immediate

predecessor of the present baseline, where the

missile and transporter were structuralIy integrated, and therefore had greatly enhanced

molbiI it y.

Another possibility would be the deployment of Minuteman /// missiIes in an MPS

mode, by constructing a large number of add itional vertical shelters in the present Minuteman missiIe fields. Proponents of this

system claim it would provide an accelerated

scheduIe for a survivabIe land-based missiIe

force, since Minuteman missiles, support infrastructure, and most roads are already available. Mod if i cations to the Minuteman misslIe

wouId be required to deploy it in a mobiIe

mode, and many additional shelters and missile transporters would need to be built. The

extent of these and other modifications is addressed, as is system cost and schedule for

completion.

Finally, several calculations of civilian

fatalities resulting from a Soviet attack on MX

deployment in multiple protective shelter

fields are presented. These calculations help

address the question of the extent to which a

Soviet strike against an MPS deployment could

indeed be regarded as “ Iimited, ”

THEORY OF MULTIPLE PROTECTIVE SHELTERS (MPS)

A land-based missile force in MPS relies for site force with confidence, will be forced to

its survivability on the assumption that the at- target al I or most of the shelters if it is not

tacker, in order to destroy the adversary’s mis- known which of these shelters contains the
Ch. 2—Multiple Protective Shelters 35

missiles. MPS thus tries to draw a distinction

between missile and target, by “immersing”

the missiIe force in a “sea” of shelters.

MPS can also be regarded as “anti-MIRV”

basing Just as MIRV (multiple independently

tar-gettable reentry vehicle) technology allows

one to attack many targets with one miss i Ie,

MPS forces the attacker to devote many warheads to destroy one real target.

For this strategy to work, the tasks of

“hiding” the missiles among the shelters and

properly sizing the MPS system for a given

level of survivability involve two key requirements Since the nature of these two tasks is

similar for all MPS basing modes, their details

and impIications are discussed in this section

of the chapter.

Preservation of Location Uncertainty

(PLU)

Inherent in the strategy of MPS is that all

shelters appear to the attacker as equally IikeIy to contain a missile This assumption is important, since if the attacker were to find out

the location of alI the missiIes, it wouId defeat

the design of the system For the planned 200

MX missile deployment, for example, it could

mean targetting as few as 200 reentry vehicles

(RVS), one RV per MX missile, which is a small

portion of the Soviet Union’s arsenal. The task

of PLU — or keeping the missile location

secret — is essential to successful MPS deployment. With increased study of this issue over

the last few years, the defense community has

come to realize the magnitude of the PLU task.

What makes PLU so challenging is that It is a

many faceted problem, dealing with a variety

of missile details Moreover, PLU must be

made an integral part of the design process at

every level. Furthermore, the present expectation is that the design process for PLU will be

ongoing throughout deployment, with continuous efforts at enforcing and improving missile

location uncertainty through improved PLU

countermeasures and operations,

To accomplish this task of missile concealment, it is necessary to eliminate all indications, or signatures, that could give away the

location of the missile One such set is the set

of alI physical signatures of the missiIe and

associated missile equipment. This set includes

weight, center of gravity, magnetic field, and

many others By utiIizing these physical signatures, missile location might be inferred by

making measurements outside the shelter or

missile transporter, looking for those signatures that could distinguish location of the

missile. Such signatures span the spectrum of

physical phenomena, many with a range of detectability of hundreds of miles, if not adequately countermeasure.

A second set of missile signatures to be

eliminated are operational signatures The task

here is to eliminate all operating procedures

that could distinguish the missile and thereby

betray its location. Otherwise, missile placement might be inferred by observing personnel

operations.

Internal information is a third set of signatures. This set includes the piecing together

of many observations to arrive at a pattern recogn it ion of data from which one can infer

missile location.

Soviet espionage efforts aimed at breaking

PLU wilI also be likely, and counterintelligence

efforts may be necessary.

Signatures

PHYSICAL SIGNATURES

The physical signatures of the missile run

into the scores, with the magnitude and range

of each dependent on design detaiIs and material construction of the missile, shelter, and

transporter. Against each of these signatures

that might compromise missile location it is

considered desirable to design and install a set

of specific countermeasures. These countermeasures include simulating missile signatures

with decoys, masking or reducing the magnitude and range of the signatures, and confusing an outside observer by engineering a set of

signatures that vary randomly from decoy to

decoy in order to make it more difficult to

determine which shelters contain the missiles.
36 ● MX Missle Basing

Table 2 is a generic list of associated missile

signatures present for any MPS system. A brief

discussion of them is included here along with

some possible countermeasures. A more detailed list and analysis is included in the classified annex.

1, Seismic/ground tilt results from the force

of missile weight on the ground, both as seismic waves set up by the motion of the missile

in transit, and static measures of its mass, such

as the tilt of the ground in the missile’s proximity, The seismic signature is particularly

significant while the missiIe is in transport between shelters, since seismic waves can propagate for miles, with a falloff in wave amplitude that varies inversely with distance.

Ground tilt caused by depression of the ground

under the missile-laden transporter falls off

somewhat faster with an inverse square law,

and a maximum ground depression of the

order of thousandths of an inch. The resulting

ground tilts are measurable at a distance, A

countermeasure for this signature may include

a mass decoy.

2. Thermal sources arise from heat generated by electrical equipment associated with

the missile, such as fans, heaters, and other environmental control systems. A measure of this

heat is the power consumed by each shelter,

typically 10 to 20 kilowatts (kW) at full operating power, Countermeasures for this signature might use thermal insulation and dummy powerloads at the unoccupied shelters.

3. Acoustic sources are due to such items as

cooling fans and missile transfer operations at

the shelter site. This signature might be countermeasure by simulation, such as suitably

emplaced recording and playback devices.

Table 2.—Physical Signatures of Missile

● Seismic/ground tilt ● Nuclear

● Thermal ● Radar

● Acoustic ● Gravity

● Optical ● Magnetic

● Chemical ● Electromagnetic

SOURCE Off Ice of Technology Assessment

4. Optical signatures are significant primarily while the missiIe is in transport. Assuming

that the transporter is covered, so that the

missile is not directly visible, concern must be

shown for the modal oscillations of the missile

transporter in a loaded v. unloaded condition,

tire deformation, exhaust smoke, and vehicle

sway angle around corners. Sensors that might

pick up this distinction range from sophisticated optics aboard a high flying plane to

ground-based lasers or even observation with

binoculars at a distance. A possible countermeasure for this signature is a massive decoy

of the same weight and simiIar vibrational

characteristics to the missile.

5 Chemical signatures are due to the routine

volatiIe chemical release from the missile,

such as propel I ant, coolant, plasticizers, and

ozone. The missile transporter exhaust may

a Isc) differ for a loaded v. unloaded case.

Chemical concentrations are expected to be as

high as 1 part per million (ppm), and methods

of detection include laser scattering infrared

absorption, Raman spectroscopy, and taking

onsllte samples for later analysis, Countermeasures may include simuIated effIuents and

a massive decoy load for the missiIe transporter,

6. The nuclear warhead on the missile has its

own signature characterized by a set of gamma ray spectral lines particular to the plutonium isotopes contained in it. The warhead

material also emits neutrons. UsefuI countermeasures incIude radioactive shielding,

7. Radar is a potential signature due to the

large radar cross section of metal objects associated with the missiIe, such as launch equipment. I n addition, distinguishing the modal

oscillations of the transporter due to different

Ioacls may be radar detectable from a distance

of severaI hundred miIes. Countermeasures for

radar include a massive missile decoy, and reliance on the metal rebar and a steel Iine for

the shelter as well as earth overburden to

radar-shield its contents,

8. Gravity field and field gradient measurements should be able to detect the mass of the

missiIe at a range of several hundred feet.
Ch. 2—Multiple Protective Shelters ● 3 7

Mass simulation is the most direct countermeasure to this threat

9. Magnetic field anomalies due to the large

amounts of metal i n the missiIe-launching

equipment, if unshielded, can be detected by a

magnetometer. Such detection techniques are

analogous to magnetic anomaly detection of

submarines, and simiIar countermeasures can

be utilized. A missile decoy containing an

appropriate quantity and distribution of high

permeability (magnetic) metal might be used

to help prevent an observer from distinguishing it from the missile.

10. Electromagnetic emissions generated by

missile equipment during normal operations

are another potential signature. I n addition,

radio frequency communication involving the

missile could lead to missile location determination by radio direction-finding techniques Electrical transients may also be detectable Countermeasures to these signatures

might consist of simulating powerline con -

sumption by installing dummy loads inside the

shelter, and communicating with the missile

during normal operation over secure buried

cable, rather than radio

The task for a potential attacker to defeat

MPS by utilizing these signatures depends on

the range of the signature to be exploited, the

covertness needed to COIIect and transmit the

data, and the degree of security provided for

the MPS deployment area Presently planned

security arrangements for the shelters are commonIy reterred to as point security, Point

security allows public access to all but a small

restricted area around the shelter, and therefore allows access relatively close to the missile shelter Area security, on the other hand,

would restrict access to most of the deployment area

Designing PLU for short-range observation,

which is anticipated for point security, is more

demanding than for long-range surveillance,

since most, though not a 11, of the missile sig

-

natures are signiticantly stronger at close

range For example, magnetic anomaly detection, which relies on measurement of magnetic

tield gradients, falls off as the inverse cube of

the distance from the source. This means that

the strength of this signature at 100 ft is more

than 1 million times as intense as this signature

would be at some 2 miIes away. Since close-in

the magnetic details of the source become

more important, the distribution of magnetic

material in the decoy is more critical for adequate deception than it would be for distant

observation.

I n addition to the short-range signatures,

there are also long-range signatures, such as

detailed motions of the missile transporter and

seismic waves, that are measurable at many

m i Ies.

The range of missile signatures strongly

determines the degree of covertness that an

agent must employ to collect missile location

information. A signature that is visible at long

ranges might require Iittle or no cover to

observe. I n particuIar, long-range signatures

wouId be particuIarly threatening if observable by satellite, since security wouId have Iittle effect; and the impact on PLU would be

catastrophic if such signatures could not be

successfuIly countermeasure. Similarly, signatures that are measurable at several miles or

tens of miles are also particularly threatening,

since security sweeps would be impractical

over so large an area, even if possible. I n the

case of long-range surveillance, the number of

sensors needed would be small compared to

the number of shelters, with the precise number dependent on signature range. It is not

clear whether covert operation of sensors

would pose a problem to the Soviets if they

found a signature that was observable at such

ranges On the other hand, short-range signatures wouId require some degree of covertness, perhaps by an implanted sensor, a roadside van, or “missile sensing” done under the

guise of another activity, such as mining. Once

missiIe location is determined there are a

number of ways to transmit the information

covert I y.

For short-range shelter surveillance, many

emplaced sensors, on the order of thousands,

would be necessary to seriously degrade PLU,

since a large portion of the shelter deployment
38 ● MX Missile Basing

would require independent observation. This

task could pose a severe problem for the

enemy agent. I n addition, the areas proximate

to the shelter would quite likely be subjected

to frequent sweeps by security forces. On the

other hand, covert sensors that could detect

missile presence in the transporter, while the

missile is in transport, could be much more

serious. Since point security wouId not secure

the roads, implants in the roads must be

prevented from determining the contents of

the transporter. In a Iinear cluster arrangement, for example, if PLU on the transporter

were to fail, then one missile-sensing device

planted in the middle of the cluster would be

able to determine which half of the cluster

contained the missiIe, thereby effectively reducing the number of shelters in half, Therefore, PLU is particularly important for the

transporter, and it must be constantly supplemented by security sweeps of the road network.

The Air Force program for deal ing with physical missiIe signatures consists of several approaches, the first of which is to eliminate the

signatures, if possible, by system design. For

example, if one construction material has a

smaller signature than another, using the first

material might be preferable, An example of

this might be the use of nonferromagnetic material, if practical, rather than iron, in order to

reduce or eliminate the magnetic signature.

These technical design requirements due to

PLU have been established for the launcher,

the mass simulator, the protective shelter, and

the transporter. The Iist of these requirements

needed to countermeasure the missile/launcher signatures, some of which were Iisted in the

previous section, and the many others that are

system- particular, is a very long Iist, that is discussed more fuIIy in the classified annex to this

sect ion

The second approach to countermeasure

physical signatures after attempting to design

them away could be to attenuate the signature

by shielding. For example, heavy material

shields gamma radiation. Thermal insulation

might be used for heat signatures, and so forth.

A signature that cannot be designed away or

attenuated might conceivably be masked or

jammed, For example, a real signature that is

measurable might be masked by an additional

large, possibly random signal, thereby making

it more difficuIt to extract the real missiIe

signature from ,the “noise. ”

If these approaches were not feasible, an attempt to simulate the signature by the use of a

decoy might be employed. This simulation is

one of the purposes of the MX mass simulator,

which will be placed in all of the unoccupied

shelters, and in the transporter when simulating missile transport, Since the simulator is

designed to weigh the same as the missile/

launcher, it automatically countermeasures

those signatures that arise from total weight.

AS discussed in the classified annex to this section, additional simulations wiII be required.

Finally, there can be physical security for

the deployment area that would consist of

monitoring the area and sweeps for sensors

that might compromise missiIe location

OPERATIONAL SIGNATURES

In addition to physical missile signatures, it

is necessary that routine procedures of missiIe

transport and maintenance do not expose the

location of the missile, This consideration

means that when carrying out missile-related

and mass-simulator-related operations, personnel must do the same things, in the same time

interval , with the same equipment at al I sites.

For example, when it becomes necessary to

return the missiIe from maintenance to the

shelter, the transporter must visit all of the

shelters and either deposit or simulate deposit

of the missile. I f the operator knows in which

shelter he is depositing the missile, care must

be taken that any actions on his part, such as

outward behavior or conversation with colleagues, do not give clues to missile location.

INTERNAL INFORMATION

This category includes piecing togethe r

many observations to arrive at any pattern

recognition of data from which one may infer

missiIe location, To deal with this considera-
Ch 2—A4u/t/p/e Protective She/tefs . 39

ponents is underway now Small

for signatures will be done in the

Figure 10. —Preservation of Location

and System Design

f 1

sca I c testing

latter halt of

Uncertainty

Characterize

I ,- .

slgnat ure

t

System

+

1 >

+ 1

Determine

basellne discriminates

Characterize

threat

v r f ? ?

Evolved Select Consider

base- Test counter. counterIlne measures measures

+ & b +

SOURCE U S AIr Force

1 ~~1 thr~ljgh the $prtng of 1982, with fllll-~c ~1~’

testing in the latter- part of 1982 through 1‘)8 3

These testj wi I I be crit [( a I in the des Ign of th~~

tran 5porter J ncj ma $~ $ i m u I ator, as ~vel I d \ for

the entire P1 U task

Assessment of PLU

Assessing the feasibll ity of the Pi-U effort is

a d i f f i c u I t task [- i rs t, I t Is ~ ~E> n u i n e I v n w

problem, a n d not a s] m p I e extra po I a t i o n of

past engineering effort~ SI nce m issi Ie signa tu re~ and their cou n t~lrmea ~u res sens I t ive I v

de~)end o n the det a i I ed d e~ ign ot t h(~ ~~~tem, i t

i \ d i f f i c u I t and c a n be m Is I e ad i ng to m a k e genera I statenlent~ about PLU

Afo physical ana I ysIs IS known that can argue

that PLU is a phyfic~l l} ir-npossible ta~k It s

a n a I yses and countermeasures rest on WC I 1-

u nderftood physic a I pr i n c i p] t’~ U nt I I re( ent I y,

however, there has been no research and dt~-

velopment program on P 1- U, nor have there

been fu Ii-scale field tests to val Idate many of

the conjectures (ind ana Iyt lcal tools needed to

design the sy~tenl I n terms of PLU scopc~, it~

deta i 1- i ntens ive c h ara cter, and 5 i m pl y as a new

techn ica I problem, comparable previous experience or data are not ava i Idbie to ~LI Ide In

judging its fea~ibi I ity I t IS true that there IJ

~orne a na I ogy with submarine detect Ion and

location I ndeecj, some PL LJ signatur(~~t most

notably magnetic, are corm mon with iu bmar i nes. St i I I, there are two i m port a n t d I \t i n c -

tions First, in antisubmarine wart~~re (A$W),

there is no present neecj to d i sc ri m i nat(~ t I1[J ac -

tua I submarine from a decoy, a Ithough re\olvi ng a $U bm a r i ne s i gn at u re from a noisy background may be one of the lead tasks Sec end,

at a technical level, the details conf rontcd

with PLU and ASW are quite distinct Th(’ envi ron ments and media are different, and the

re Ieva nt signatures and the ava i I a b I(’ c~ i sta n ce

at which the measurements can be performed

are different (much closer for MPS) S i reply

stated, solving the tech n i ca I A SW p rob I em

does not significantly help solve PLU, ctnd vice

versa

I n addition, it is not known at this point of

techn ica I PLU work, how feasible [t wi I I be to
40 . MX Missile Basing

eliminate, attenuate, mask, simulate, or randomize all of the missile’s signatures, or what

the residual signatures will be. Since this is a

detailed engineering task, confidence cannot

be obtained until full-scale field tests have

been done, when missile signatures can be

more retiably identified and analyzed.

Thirdly, it may not be possible to be certain

that PLU has not been broken by the Soviets; a

break (or even a small fracture) of PLU may

likely be a silent event. For all the scores of signatures that have been successfulIy countermeasure, it takes only one accessible uncountermeasured signature to imperil the survivability of the entire missile force. On the

other hand, it is reasonable to expect that personnel running a vigorous program to monitor

PLU in operation will be more aware of compromises in the system than an outside agent

wouId Iikely be, Furthermore, a compromise in

PLU would not necessarily be catastrophic,

since a breach in PLU for several shelters or

even several missiles would not significantly

threaten the entire force. I n any case, confidence in our having PLU is an important factor in its own right. In addition to being based

on knowledge of our own system, confidence

is also a state of mind, and not always easy to

judge or predict,

Finally, the extremely high value of the

knowledge of missile location must be emphasized. Because this knowledge holds the

key to MX survival in a Soviet attack, a

vigorous Soviet effort in this area shouId be expected, underscoring the technical and operational importance of the PLU effort. The Air

Force effort for PLU, which several years ago

may have underestimated its scope and difficulty, has more recently proceeded with a

program that is comprehensive and realistic in

its approach. However, whether this or any

other program will succeed in developing a

technology that wiII successfully keep the missile hidden is a technical assessment that cannot be made at this point, at least until fullscale hardware exists and can be tested for all

missiIe signatures,

Sizing the MPS System

For MPS to provide a given degree of survivability to its missiIe force, an adequate

number of shelters must be deployed so that

the entire system can absorb an attack, and

stilI leave the required fraction of the missile

force intact. Determining the number of shelters to be built and the deployment area of the

system depends on a number of factors: the

hardness and spacing of the shelters, the accuracy and reliabiIity of enemy missiIes, the number of threatening warheads, and the size and

survival requirements of the U.S. missile force,

Since the idea of MPS is not to build a

shelter that can survive a direct hit, but one

that can survive the effect of direct hits on its

neighboring shelters, the requirements for

shelter hardness are much less than for the

typical Minuteman silo.

The overpressure experienced by the shelter

depends on its distance from the nuclear

detonation(see fig. 11). For any MPS system,

Figure 11 .— Peak Overpressure From 1-MT Burst

10’ 1 o’ 10” 10’

Ground range (ft)

SOURCE RDA
Ch, 2—Multlple Protective Shelters ● 41

there is a tradeoff between shelter hardness

and shelter spacing. The harder the shelter is

made, the closer the shelters can be spaced

and still withstand the effects of nearby nuclear detonations. Conversely, the farther

apart the shelters are spaced, the less hard the

shelters need be made. I n practice, the shelter

spacing and hardness combination is determined by cost trade-offs between increased

shelter hardening (that requires a larger shelter

and more concrete) and increased shelter spacing (that requires more roads and buried communications and electrical connections between shelters), in order to reach a cost minimum solution.

The reliability and accuracy of enemy missiles are also important factors for deciding

how many protective shelters to build, Reliability is the probability that the missile, when

given the order to fire, will fire and operate

properly along its trajectory. When planning

for shelter deployments, more shelters will

clearly be needed for a high enemy missiIereliabiIity than for a low one. Missile reliabilities

are typically between O 8 and and 1.0, and

their effect on vulnerability calculations will

be illustrated later in this section.

Missile accuracy is a measure of the missile’s abiIity to land a nuclear warhead on its

target TypicalIy, missile accuracy is measured

in terms of CEP, or circuIar error probable. CE P

is defined as that distance from the target

within which half of the warheads would land

if target ted A large CEP means a less accurate

missiIe; a smalI CE P means a more accurate

missi le.

Missile Accuracy depends on a variety of

factors, both internal and external to the

missile The heart of the missile’s guidance Iies

in its inertial measuring unit (I MU). Placed in

the upper stage of the rocket, the IMU senses

missile accelerations throughout the boost

phase, integrates the signals to get velocity

and position data, and uses this data to navigate the missiIe to the warhead’s release

point Contributions to target miss, called the

error budget, include the following items:

● smalI errors of instrumentation and calibrat ion,

● knowledge of initial position and velocity

of missiIe,

● I MU platform alignment,

● knowledge of gravity for the launch point

region and missiIe trajectory,

● knowledge of target Iocation,

● RV separation from the missile bus, and

● errors during atmospheric reentry.

Knowledge of the missile’s CE P and reliability,

and the hardness of the target, allow the pro babiIity to be calcuIated that the target wiII be

destroyed in an attack There are standard

tables for this caIcutat ion, but for present purposes, the following formula is adequate tor

the probability that a reliable RV will destroy

its target, or pk:

P

k = 1 – exp1 26(YH

where

Pk = the probability of kill

Y = the yield of the weapon, in megatons

H = the hardness of the shelter, in thousands of p\ I

CEP = circular error probable, In kilofeet (thousands of

f t )

For example,

Yield Y = 1 MT

Hardness H = 600” PSI (or () 6 thousand psi)

C E P = 1,800 ft (or 1 .8 k ilofeet)

then

Pk = 50% (or 0.5

This answer corresponds to the fact that the 600

psi contour for a 1 MT detonation occurs at

the 1,800-ft contour. Since, by definition of

CEP, half of the time the weapons would fall

within 1,800 ft of the target, and halt of the

time they wouId falI outside 1,800 ft, then the

probability of k ill is exactly so percent

Typically, modern intercontinental ballistic

missile (ICBM) accuracy is much better than

this, and for shelters of hardness less than

1,000 psi, the probabiIity of k i I I (given the

proper yield) is close to 100 percent (or 1 .0).

Furthermore, the furture trend is for pk to be so

close to one that the expectation of destroying

a I most any such target is approximately equal

to the retiabiIity of the attacking missiIe
42 MX Missile Basing

An MPS Calculation

A typical MPS calculation is now performed

Suppose the reliability of the attacking missile

times its Pk (which is the expectation o f

destroying the target) is 0.85, for example. Suppose further that there are 4,000 attacking warheads of I-MT yield each. The expectation is

that this attack can destroy (4,000) x (0.85) =

3,400 shelters. Therefore, after such an attack,

an MPS force of 6,800 shelters would have half

of the shelters remaining. Without the attacker’s knowledge of missile location it could

be expected that half of the missile force

would also survive (see table 3).

To address the sensitivity of missile survival

to the size of the threat, using the above example as a base case, the percentage of surviving

missiles v, number of threatening RVS is shown

here in figure 12. As before, a reliability of 0.85

and a pk close to one is assumed. The number

of surviving misslIes falls off Iinearly with increasing numbers of attacking RVS at the rate

of 0.85 shelters per RV, until RV number equals

shelter number, 6,800 At this point, 1,020

shelters wouId remain, or 15 percent of the

missile force would survive, If the attacker

chooses, and if he has the warheads, he can attack with a second round of RVS. Assuming

that he does not know which shelters he destroyed during the first round, he attacks all of

the shelters again, with a 15-percent efficiency

of targeting among the shelters that are still

standing (since 15 percent of the shelters survived after the first round). Ideally the second

slope is 15 percent of O 85, or 0.1275 shelters

destroyed per RV, but fratricide effects (beTable 3.—MPS Example

Assume: –

● 200 MX missiIes

● 4,000 attacking warheads

● 0.85 probability of kill times reliability

Requirement:

● 50% survival of missiIe force

Shelters vulnerable:

● 4,000 x 0.85 = 3,400 shelters

Shelters required:

● 3,400/50°/0 = 6,800 shelters (assuming perfect PLU)

SOURCE Office of Technology Assessment

Figure 12.—Surviving Missiles v. Threat Growth

for MPS Example

100 %

(Example: Pk x reliability = O 85)

—

c

I

15% —

2 % —

4,000 6,800 13,600

Number of reentry vehicles attacking

SOURCE Office of Technology Assessment

tween the first and second rounds) might flatten out this second slope significantly.

The rationale for MPS in this hypothetical

example can be seen in the following way, Suppose the MX missile were deployed in an MPS

with a ratio of 1 missile per 34 shelters. This deployment includes a total of 200 MX missiles,

with 2,000 Mk 12A warheads, It wouId take, on

the average, 34 perfect attacking RVS to

destroy an MX missile with its 10 warheads, or

a ratio of 3.4 attacking RVS to destroy 1 MX RV

(assuming we had perfect PLU). This ratio

would be in contrast to undefended silo basing, where it wou Id take at most two RVS (for a

much harder shelter), to destroy 1 MX missile

with its 10 RVS, or a ratio of 1 to 5, in favor of

the attacker.

Shelter Requirements

This discussion is completed by addressing

actual MPS shelter requirements for the MX set

by the size of the possible Soviet threat. As discussed earlier, any MPS system is sized, in part,

to the opposing threat; there is no absolute

number of shelters that will guarantee safety

for the missile force, but only a number relative to the opposing number of nuclear warheads. Therefore, for MPS to be survivable, it

should be keyed to and keep pace with the

evolving Soviet threat. Given the size and char-

44 MX Missile Basing

based on actual MX cost models suggest that

the ratio of 1 to 23 is not far from costoptimum. Shelter number requirements are

shown in figure 13. This graph shows that for

an undefended MPS, approximately 8,000

shelters will be needed by 1990, and that by

1995, an adequate MPS will require approximately 12,500 shelters. (The knee in the curve

occurs on the chart where reliability alone

guarantees the required number of surviving

MX missiles.)

Past the point of 8,000 to 9,000 shelters, it

may be decided to deploy a ballistic missile

defense, such as LoADS. It will become apparent that LoADS effectively doubles the

price that the attacker must pay to destroy an

MX missile in an MPS deployment. Therefore,

if LoADS performs properly, an 8,000 shelter

deployment with LoADS defense would be

equivalent to a 16,000 shelter, undefended

MPS deployment, and is commensurate with

our projections for Soviet threat growth in the

1 990’s,

Figure 13.— M PS Shelter Requirement for Projected

Soviet Force Levels (100 Surviving Missiles)

Number of

shelters

15.300

12,500

8,25C

460 ,—- 0

2,700 7,000 12,000 15,300

Soviet RVS targeting MX

Assumptions

● 1 mlsslle for every 23 shelters

● Damage expectancy O 85

SOURCE Office of Technology Assessment

In addition to properly sizing the MPS system, it is also necessary that it keep pace with

the expanding Soviet threat, so that it is large

enough to meet the threat at any given time i n

its deployment. An expanding MPS that lags

behind the Soviet force growth is not an effective deployment. Therefore, the rate of shelter

construction should be chosen to keep up with

the expected rate of Soviet growth. For an

8,000 shelter requirement by 1990, and an IOC

(initial operating capability) for 1986, it would

mean buiIding shelters at the rate of 2,OOO per

year, instead of the presently planned rate of

about 1,200 per year. After 1990, additional

shelters would need to be built at the rate of

about 1,000 per year. Alternatively, a LoADS

defense would need to be installed. It should

be pointed out that the decisions on shelter

construction rate and LoADS defense are longIeadtime items, and the decision to proceed

wouId need to be made several years prior to

construct ion.

Weapon Characteristics for M PS

Because the MX missile is stationary in an

MPS basing, except for the periodic relocations during missile maintenance, the weapon’s characteristics are essentiaIIy the same as

fixed-silo ICBM basing. Thus, the system

possesses a very high alert rate. It also has a

quick and flexible response with a very hard

target capability. The communications systems available are many and redundant, including land Iines during peacetime and wartime radio links. Furthermore, the missile force

is not dependent on strategic or tactical warning

, unlike the bomber/ALCM leg of the Triad.

It also has the highest potential for endurance

and is capable of operating in a dormant (low

power) mode for long periods of time with selfcontained power supply (batteries),

Moreover, fixed land-based

ditionally set the standard

curacy, for several reasons

previous Iist of contributions

ICBMS have trafor missile acRecalling the

to missile CEP,
Ch. 2—Multiple Protective Shelters ● 45

three relevant items are. 1 ) knowledge of initial

position and velocity of the missile, 2) IMU

platform alignment, and 3) the value of gravity

in the launch point region and along the

missile’s trajectory Because the missile launch

position is fixed, its position and velocity are

known with great precision. Similarly, being

stationary easily allows the IMU to keep track

of its alignment In addition, gravity maps

need to be prepared for the Iimited area in the

proximity of the launch point These items

tend to make pure inertial guidance much

simpIer for fixed missiIe basing than for com

tinuously mobiIe basing that must u palate position coordinates and velocity by external aids

if sufficiently accurate gravity data are not

ava i table.

For MPS, once the missile is relocated, the

guidance platform needs to go through a

recaIibration and reaIignment The requirement to reacquire CEP (i .e , highest accuracy)

after relocation is 2 hours.

THE AIR FORCE BASELINE

The Air Force baseline system for the MX

missile is an MPS system for a force of 200 MX

missiIes to be deployed i n the Great Basin region of Utah and Nevada. It would deploy

these missiles among 4,600 hardened concrete

shelters, a ratio of 23 shelters per missile. In

the present design, the shelters would be laid

out in clusters of 23: one missile per cluster;

200 clusters in all. Large, specially constructed

transporter trucks would move the missiles

with in the cluster to help preserve location uncertainty and to transport the missiIe to maintenance when the missile is in need of service.

The present schedule calls for an initial

operating capability (IOC) of 10 clusters (10

MX missiles in 230 shelters) for 1986, and a full

operating capability (FOC) for the complete

system in 1989: an average construction rate of

about 1 cluster per week, or 1,200 shelters per

year, Testing of the missile itself is planned to

begin early 1983, with a schedule of 20 flight

tests before IOC.

This section begins with a detailed design

description of the system, including missile

and launcher equipment, shelters, transporter,

and cluster layout. Land use requirements,

based on siting criteria, needs of physical

security, and other elements of the system are

discussed, as are the regional impacts, both

physical and socioeconomic, water availability, and impacts on regional energy growth.

Finally, system schedule and cost for the current baseline system and the expanded systems

are analyzed. The section is concluded with a

treatment of a split-basing mode for MPS.

Discussions of preservation of location uncertainty (PLU) for the missiIe, and determining

adequate shelter number, i.e., sizing the MPS,

are covered in the previous section on the

theory of MPS.

System Description

Figure 14 shows the general layout of the deployment and assembly area.

The missile is first assembled in an area outside the deployment area. The missiIe is

assembled stage by stage, into a close-fitting

missile cannister, that provides environmental

control, allows for ease of handling during

transport, and supports “cold” launch ejection

from the capsule. This cannisterized missile is

then joined with a specially constructed missile launcher. The launcher (fig. 15) that is

deployed along with the missile as a structurally integrated unit, consists of the launching

mechanism that erects the missile for launch,

radio receivers for communication, and survival batteries after an attack. The launcher

also contains an environmental control unit

for continuous temperature, humidity, and

dust control. The Iauncher’missile assembly is

designed to weigh about 500,000 lb, and it is introduced into the shelter cluster where it is

deposited in the cluster maintenance facility

(where minor repairs also can be performed
46 ● MX Misslle Basing

Figure 14.—System Description

Minimum shelter transportation

spacing-5,000 ft

Designated assembly area

SOURCE U S Air Force

when necessary). From the cluster maintenance facility, the Iauncher/missile unit is

then moved to its protective shelter via a

specialIy designed and engineered transporter,

which is also assembled in the assembly area

and moved to its own cluster. In the current

design, each of the 200 clusters will have one

cluster maintenance facility and one launcher-l

missile transporter, for a total deployment of

200 cluster maintenance facilities and 200

t ran sporters. Alternate designs under consideration call for “clustering the clusters, ” so

that fewer cluster maintenance facilities and

transporters, perhaps one quarter of those that

are presently planned, will need to b e

deployed.

Once the missile is placed in its shelter it remains there until movement is necessary,

either for reasons of missiIe or launcher maintenance, changing missile location if necessary

for preservation of location uncertainty, or for

arms control monitoring by satellite. The same

t ran sporter also installs a missile/launcher

decoy, called a mass simulator, into the other

22 shelters that do not contain a missile. The

purpose of the mass simulator is to make it impossible for an outside observer to determine

whether a missile or a mass simulator is in a

given shelter (or transporter), at a given time,

by duplicating many of the physical characteristics of the missile with launcher

Throughout the missile deployment area

thousands of miles of roads would be constructed to connect the shelters, clusters, and

assembly area; in add it ion, thousands of miles

of underground fiber optic cable would pro-
Ch. 2—Multiple Protective Shelters . 47

Figure 15.—Launcher

AFT

equipment

module

I

Cannister

Forward

equipment I

module

I

Length

Diamete

Weight

SOURCE U S Air Force

vide peacetime commun

155 Feet

110 Inches

500,000 Pounds

cat ion with the missiIe launcher The tiber optics wouId also

transmit reports on missile and launcher

status, and couId transmit the order to Iaunch

the missile. Since these land-line communicantions couId be easily interrupted and destroyed in a nuclear attack, the MX fields rely

on backup radio communication Iinks between the launcher and higher authority An

airborne Iaunch controI center (ALCC), always

on airborne alert, would serve as a radio relay

for two-way communicat ion with higher authority Other radio Iinks presently designed into the system that do not rely on the ALCC for

relay, support one-way communication from

higher authority to the missile launcher. All

radio signaIs are picked u p by a medium frequency (MF) antenna, buried nearby each

shelter

Since the missile is stored in a horizontal

position whiIe in the shelter, the missile launch

sequence wiII involve opening the shelter door,

a partial egress of the missile/launcher so the

missile portion of the launcher is fully outside

the shelter, erection of the missile to a near

vertical position by the launcher, and finally

ejection of the MX missiIe from its launch cannister by generated vapor pressure and subsequent missile engine ignition (see fig 16)

Figure 16.— Missile Launch Sequence

Launcher emerged and erected to launch position

SOURCE U S Air Force

Along with the above mentioned elements,

the Air Force baseline includes two MX operating bases, including housing areas and airfields, three to six area support centers, and

other support facilities.

These elements are now discussed in detail.

For notational purposes the term “launcher”

wiII refer to the missiIe-cannister-launcher

assembly.
48 MX Missile Basing

Missile Cannister and Launcher

The missile cannister is a hardened tubular

structure (fig. 17) designed to house the missile

horizontally prior to launch, and to provide

the impulse, in the form of high pressure

steam, to eject the missile from the cannister, a

procedure known as cold launching. The missile is supported in the cannister by a series of

pads to restrain the missile and reduce loads

on it during transport and nuclear attack. The

pads are arranged as a set of circumferential

rings along the motor casings. The high pressure steam for missile ejection is generated by

a water cooled gas generator, producing pressures sufficient to eject the missile from the

cannister with an exit velocity of approximatey 130 f t/see.

The launcher assembly (see fig. 15) is made

up of several components, and several sections. These parts include a forward section,

consisting of a forward shock isolation system

to help cushion the missile during nuclear attack, and a set of rollers for transferring the

missile to and from the transporter and protective shelter. The middle section of the

launcher holds the missile/cannister assembly,

Figure 17 .—Cannister Construction

/

\ /

Aluminum

splice band

and the aft section contains command, control, and communications gear, emergency

batteries, and a second set of rollers for missile

transfer. Total weight of the missile-launcher

unit is expected to be about 500,000 lb,

Erection of the cannister for launch is

achieved by a SIiding block and connecting rod

Iinkage, initiated by a pyrotechnic actuator.

Protective Shelter

The protective shelter would house and conceal the launcher and would be designed to

protect it during nuclear attack. Essentially, it

wouId be a cylinder of reinforced concrete, approximately 170 ft long, and lined with 3/8 inch

steel to protect the missiIe against nuclear

electromagnetic pulse effects. It would have a

14.5-ft inner diameter and 21-inch thickness; it

wouId be buried under 5 ft of earth, with an exposed concrete and steel door 10 ft off the

ground, as shown in figures 18 and 19. A garage

type structure, the shelter would house the

launcher horizontally; hence the name,

horizontal shelter.

In the present design, allowance is made to

have two plugs installed in the roof of each

shelter Removing the plugs would allow selective viewing of the shelter contents by satellite

to help assure arms control verifiability.

A fence around each shelter would enclose

2.5 acres, an area also guarded by onsite intrusion sensors and remote sensors as part of the

physical security system.

The shelter support equipment, including

environmental control, AC/DC conversion, and

emergency batteries, would be housed outside

each shelter, but within the fence.

Transporter

The transporter would be a manned roadable vehicle that would carry the launcher

within a cluster between shelters and the

cluster maintenance facility (see fig. 20). It is

also designed to transport the mass simulator,

and to perform the exchange of launcher with

simulator whiIe parked at the protective

SOURCE. U S Air Force shelter.
Ch. 2—Multlple Protective Shelters ● 49

Figure 18.— MX Protective Shelter Site

The transporter would be a heavy vehicle,

weighing 1.1 mill ion lb unloaded, and 1.6 million lb when loaded with the launcher or mass

simulator. It would be about 200 ft long, 31 ft

high, and would require 26 tires. The transporter’s cargo bay would be constructed to hold a

launcher and mass simulator, or two mass

simulators, at the same time for purposes of

exchange at a shelter (see fig. 21) This exchange is to be accomplished by providing two

sets of rolling surfaces in the transporter, one

for the launcher and one for the mass simulator, and an elevator inside the transporter to

position the cargo for transport (see fig. 22).

Transfer of the cargo at the shelter site would

be accomplished by an electrically powered

rolI transfer.

Like the shelter, the transporter is designed

to have two ports on its roof to permit selective viewing of its contents for purposes of

arms control verification.

The transporter is designed to protect itself

and its contents from the electromagnetic

pulse of a high altitude nuclear burst, but it

wouId otherwise be vuInerable to nuclear attack. Power to the transporter would be supplied by 10 drive motors and 2 turbo generators. It would have a 15 mph capability on

level road, and would have automatic guidance with manual override. It would be manned during all transport activities.

Mass Simulator

The MX mass simulator would be an archshaped structure made of reinforced concrete

(see fig 23). It is designed to match the launcher’s weight (500,000 lb), center of gravity loca-
50 . MX Missle Basing

Figure 19.— MX Protective Shelter

SOURCE. U S Air Force

Figure 20.—Transporter tion, external magnetic characteristics, and

Characteristics

Length: 201 feet

Width: 16 feet (over tires)

25 feet (overall)

Height: 31 ft 6 in.

Weight: 1,600,000 Pounds

(loaded)

Tires: 26

Drive motors: 10

other signatures, so that when it occupies a

shelter, or when it is carried by the transporter,

it could not be distinguished from the missile

by an outside observer, Square openings, or

notches, are located in the top of the simuIator

arch, and aligned with the plugs in the shelter

roof, so that during arms control verification

activity, when all of the shelters are occupied

by mass simulators and the shelter plugs are

removed, a satelIite

openings in the mass

observe the absence

shelter.

The mass simulator

with running gear to accomplish its roll transfer into and out of the transporter. There

would be a separate, upper ledge in the shelter

to support the simulator. For reasons of PLU,

could see through the

simulator, and thereby

of the launcher in the

also would be provided

the simulator’s running gear and its axial locaSOURCE U S Air Force tion wouId be the same as the launcher.
Figure 21 .— Missile Launcher and Simulator—

Transfer Operations

Simulator-simulator transfer

Simulator

Simuiator-launcher transfer

Simuiator

Launcher

I

I

SOURCE U S Air Force

Cluster Layout

Each cluster would contain 23 shelters, arranged more or less along a Iinear string, and

connected by a cIuster road (see fig. 24). Spaci ng between adjacent shelters would be

approximately 5,200 ft, with a minimum spacing of 5,000” ft In addition to the 23 shelters,

La

Figure 22.— Mass Simulator (MS) and

Launcher Exchanges

I

Shelter

MS #1

MS #2

MS/MS fake exchange

A

porter

Launcher/MS exchange

SOURCE U S Air Force

each cIuster would contain a cluster m a Intenance faciIity (CM F), where minor repair-s on

the launcher could be accomplished, and that

could house the transporter when not in use,

Most of the time the cluster would be unmanned, except for maintenance activities,

SALT verification, and security patrols
Simulator

SOURCE U S Air Force

Figure 24.—Cluster Layout

SOURCE U S Air Force

Within each valley, the shelters would be arranged in a close-packed hexagonal pattern

(see fig. 25). The lattice is not completely

filled, having approximately one-third fewer

shelters than the spacing actually allows. The

Diameter 150 inches

Length 155 feet

Weight 500,000 pounds

reason for this design is that the confluence of

the shock fronts from the nuclear detonations

at the vertices of the hexagon could be sufficient to destroy a missile placed in a shelter at

the center of the hexagon. Consequently, this

center shelter has been left out. In the event of

a Soviet effort to increase their n umber of missile RVS, it is presently contemplated that

these “gaps” in the hexagonal layout will be

“backfilled” with additional shelters. If the

Soviets fractionate their warheads, thus decreasing the individual warhead yields sufficiently, backfilling could be feasible.

Command, Control, and

Communications (C3

)

The C3 system (see fig, 26) is divided into two

categories: peacetime and wartime. The

peacetime/preattack C3 system would consist

of a centralized command control located in

the operational control center (OCC), at the

base, and a communications network spanned

by an extensive underground grid of fiber optic
Ch. 2—Multiple Proctive Shelters ● 5 3

Figure 25.—Shelter and Road Layout

5,200-ft spacing

SOURCE U S Air Force

cable between the OCC and al I of the missile

launchers The OCC would be in continuous

two-way communication with higher authorities, incIuding the airborne national command

posts (Looking Glass, NEACP, etc ) and the National Military Command System (NMCS) The

fiber optic cable system would have a high

data rate (48 kilobits/sec) with a relatively long

attenuation length, Because fiber optic cable

is a dieletric, it is resistant to electromagnet Ioss

pulse (EMP) effects By making the cable sufficiently thick, a protective metal sheath might

not be required to protect it against gophers,

gerbils, and the like, Each Iine contains three

fibers (one for communication in each direction and one spare) PLU would be maintained

by uniform formatting and message protocols

for missiles and simulators The entire system

would require about 11,000 miIes of cable,

The peacetime C3

‘ system is not intended to

survive a nuclear attack, since the operational

control center would be a primary target, and

fiber cable connectivity would be interrupted

by cratering. The postattack C’ system would

take over at this point. The postattack system

would consist of an airborne launch control

center (ALCC), that wouId have two-way comm u n i cation with the missile force via MF

(medium frequency) radio The ALCC’ plane

wouId a I ways be airborne, with a backup ALCC

on strip aIert. Each shelter would have buried

beside it a 600 ft crossed M F dipole antenna,

that would serve as a receiving and transmitting antenna The transmitting power at the

sheIter is 2 kW, and with a soil propagation

loss of – 30 db, wouId transmit 2 watts effetive radiative power MF was chosen, in part

to combine the advantage of high frequency

data rates with low frequency propagation

through ionized, nucIear environments. In addition, MF does not propagate through (or, at

least, is greatly distorted by) the ionosphere,

making reception intentionaIIy difficult by

sateIIite. In the present design, MF wouId be

the only means by which the missiles could

“talk” to command authority Therefore, when

the ALCC would no longer be operational, the

launcher would not be able to report back to

higher authority,

In addition to two-way MF radio, the baseline is designed to have one-way radio communication from higher authority directly t o
54 . MX Missile Basing

Figure 26.—Command, Control, and Communications System

VLF/HF

cable

Protective Structure

Launcher C3

MF transceiver

VLF HF Receivers

Microprocessor

Crypto

Shelter C3

Fiber optic modem

Hardened LF VLF MF antenna

Microprocessor

Crypto

SOURCE U S Air Force

the launcher via high frequency (HF) and very

low frequency (VLF) when the ALCC is no

longer airborne (in-flight endurance of the

ALCC is about 14 hours). Two-way communication between higher authority and the launcher via H F is presently contemplated, so that the

launcher can give status and report back when

the ALCC is not operational. We should point

out that even if two-way H F were installed it

wouId not necessariI y assure continus, longhaul communication. Because the ionosphere

would be disturbed for a period of hours after

the initial attack before slowly recovering,

long-haul HF via ionospheric skywave cannot

Characteristics

Command and Control

Preattack

Operational control center

Alternate operational

control center OCCCAOCC

Postattack

Airborne Launch Control

Center (ALCC)

Airborne National Command Post/

National Command Authorities

(ABNCP/NCA)

Communications

Preattack

Fiber optic cable

UHFCVHF voice

PAS SAC DINCAFSAT

VLF MF*HF

Postattack

VLF MF/HF

always be depended on (Adaptive HI techniques wouId not sol VP the interruption of

transmission, a I though it couId recover more

quickly than conventional H F ) H F antennas

would probably have to be added to the

system In addition to the buried MF antennas,

since using the same MF antenna for HF

transmission would incur a variety of technical

problems,

To help assure receipt of the launch command by all of the launchers from the ALCC,

the launcher that first received the message

would rebroadcast the same message by MF
Power Supply System

Figure 27. —Electrical Power Distribution
56 ● MX Mlsslle Basing

Figure 28.— MX.CannisterlMi ssile Launch Sequence

4

Earth berm

Cannisterlmissile full egress

M

ub~ll ~

~11 1

.

.

.-

,-

1

!

.

.

Missile cannister - 1

Launch position

Y

SOURCE U S Air Force

6. The missile is expelled from the cannister porters could also be used for relocation of

by the hot gas steam generator, at an exit

velocity of about 130 ft/sec.

7. The missile’s stage 1 fires,

The entire missile launch sequence is designed

to require several minutes.

Missile Mobility

In the baseline system, the transporters are

intended primarily to move missiles between

the cluster maintenance facilities and shelters

for the purposes of maintenance, supporting

arms control verification, and PLU, The transmissiies among cluster shelters (but not between clusters). Because there are 200 transporters and 200 missiles, it would be possible

to move al I of the missiles at the same time,

although this is considered very unlikely because it wouid leave all of the force outside

the /protective shelters and exposed to a preemptive attack.

Another possibility would be to keep a fraction of the missi Ie force on transporters, on the

road. When the warning of an attack came, the

on-road missile force would “dash” into the

nearest shelters.
Ch. 2—Multiple Protective Shelters ● 5 7

There is some advantage to these mobility

options, but there are limitations as well. If a

partial or complete breakdown of PLU is

suspected, then any number of missiles can be

relocated in new shelters, This relocation

wouId be performed by a visit of the missile

transporter to each shelter, where it would

either simulate or perform a n authentic missiIe

pickup or deposit The time it would take to

perform this operation for the entire missile

force has been estimated to be about 9 to 12

hours, after which time the missile could be in

a different position so that previous Iocat ion

information possessed by the enemy would be

invalid Figure 29 shows the timeline for this

“rapid” relocation, A decision to relocate all

of the missiles at the same time would be

unIikely, in view of the earlier discussion.

Depending on how PLU was broken, this relocation might or might not reestablish the

location uncertainty If PLU had been broken

by long-term efforts at data collection or espionage or both, then rapid relocation could

reestablish PLU If, on the other hand, the

enemy could locate the missiles through technical or other means in a short time, then no

amount of relocation would reestablish PLU.

The second mobility option, the “dash” or

hide-on-warning option, would place a portion

of the missiIe force on the road, i n motion or

parked near a shelter Upon warning of attack,

the manned transporter would dash to the

nearest shelter, deposit the launcher, and back

off from the shelter so that the missile could

egress and launch The time estimate for this

operation is SIightly u rider 6 minutes, which

would be required to respond to warning of a

submarine launched ballistic missile (SLBM) attack, and secure the missile in the shelter

before the attacking warheads arrive

The dash timeline for this operation is

displayed in figure 30. Since the transporter is

not designed to withstand an SLBM attack, it

cannot be used after the attack. The advantage of this option is that it acts as a hedge

against a complete breakdown of PLU, so that

at least a fraction of the missile force might

survive the initial attack This option assumes

that the attacker does not know the location of

the missile at the time of the attack This may

or may not be true, since it depends on the

ability of his reconnaissance to observe transporter location, and use this information to

Figure 29.—Transporter Rapid Relocation Timeline

Time (minutes)

Task o 100 200 300 400 500 600

I I I I I I

CMF activities

‘ 540

I

9 Hrs -

I

n

I

Travel to shelter site 17 17 I

I

1

I

I

:

I

I

Dwell time at shelter 138 I

t

sites (23 sites — I 1

1 ; maximum) I 1

I

I

Travel time 368 ~ ;2 3

(between 23 shelter 1 :

sites 1 ,

Travel to CMF 17 5 4 0

I

CMF activities u

Total travel time = 17 + 368 + 17 = 402 minutes

SOURCE U S Air Force
58 . MX Missile Basing

Figure 30.— Dash Timeline

Task

Command initiation 2

Travel time 231

Open closure and position 37

transporter for transfer

Prepare for transfer 12

Remove simulator 28

Emplace launcher 46

Remove transporter 5

Secure protective shelter 23

SOURCE U S Air Force

Time (seconds)

100 200 300 350

I I I

I

I

I

I

I

- 2 3 3

I

196 233

I i

2 4 5

I

1

I I

I

I

328 350 I

I

1

target the shelter into which the missile would

seek cover. Without commenting on the present Soviet capabilities to accomplish this task,

it might not be wise for the United States to

rely on dash as a substitute for PLU. The job of

real-time reconnaissance and retargeting of

shelters in order to defeat the dash option is

not technically infeasible, although it may be

high-risk in the near future. Thus, reliance on

dash may be a useful hedge against a loss of

PLU in the near term, but its long-term prospects are more uncertain.

Secondly, after a first attack, reconnaissance would be able to locate the transporter. Since the transporter would be located

next to the occupied shelter, the attacker

would know the location of the dashed missile,

and could attack it on the next wave or by

bomber force if the MX missile were not

launched in the time remaining.

Finally, since dash relies on warning of attack, it would have a common failure mode

with the bomber force, again underscoring the

importance of maintaining a PLU-perfect system, rather than relying on missile mobility as

a hedge.

SALT Monitoring Operations

The basic need to verify missile numbers for

an MPS deployment, without compromising

missile location uncertainty, is satisfied by

allowing the means to count missile numbers

Without determining specific missiIe location.

This capability is being designed into the system, by following a slow, open, and observable

missile and launcher assembly process in the

assembly area. This process would allow national technical means to observe each missile

constructed in the assembly area, before it is

deployed in a shelter cluster. Second, there is a

unique paved connecting road between the

assembly area and the deployment area, and a

special transporter vehicle to move the missiIe

and launcher to the deployment area, Third,

the missiles and launchers would be confined

in clusters, with cluster barriers that would
Ch, 2—Multiple Protective Shelters ● 59

make removal and replacement of launchers

and missiles observable by satelIite.

To further facilitate SALT monitoring of the

missile force by national technical means

(NTM), plugs in the roof of each shelter have

been designed as part of the system. The monitoring process would proceed as follows:

2.

3.

4.

The transporter deceptively relocates the

missile from the shelter to the cluster

maintenance facility, leaving a mass simulator in each shelter of the cluster.

Special vehicles would clear the 5-ft overburden on top of the shelter, and the two

SALT concrete ports would be removed

from the top of the shelter, exposing the

contents of the shelter to satelIite reconn a issance,

The shelters would be left in this configuration for 2 days to accommodate

NTM viewing,

The SALT ports would be replaced, the

overburden restored, and the missiIe returned to one of the shelters. The estimated timeline for this process is illustrated in table 4.

Siting Criteria

There are three fundamental siting criteria

that apply to any MPS site selection process:

●

●

first, large areas of relatively flat land are

necessary to permit clusters of shelters

and to allow transport of the missiles

among shelters;

second, for the purpose of minimizing

construction costs, it is desirable to have

Table 4.—Monitoring Timeline

Remove missile 1 day (12 working hours)

Remove SALT ports 1 day (12 working hours)

NTM inspection 2 days

SALT port replacement 2 days

Replace missile 1 day (12 working hours)

Total 7 days —

areas with minimal water resources and

hardrock formations near the surface; and

third, for the purpose of minimizing the

number of people displaced or otherwise

impacted by construction and to minimize threats to PLU from public activities,

it is desirable to have a low-population

density area,

The siting criteria indicated in table 5 reflect

these principal considerations:

On the basis of these screening criteria, the

Air Force identified 83,000 mi 2 of geotechnicalIy suitable lands throughout the Western

United States and defined six candidate areas

for “militarily logical deployment” that were

Table 5.—Principal Exclusion/Avoidance Criteria

Used During Screening

Category Criteria definition

Geotechnical Surface rock and rock within 50 ft.

Surface water and ground water within

50 ft.

Cultural and Federal and State forests, parks,

environmental monuments, and recreational areas.

Federal and State wildlife refugees,

grasslands, ranges, and preserves.

Indian Reservations.

High potential economic resource

areas, including oil and gas fields,

strippable coal, oil shale and uranium

deposits, and known geothermal

resource areas.

Industrial complexes such as active

mining areas, tank farms, and

pipeline complexes.

20 mi. exclusion radius of cities having

populations of 25,000 or more.

3.5 mi. exclusion radius of cities having

populations between 5,000 and

25,000.

1 mi. exclusion radius of cities having

populations less than 5,000.

Topographic Areas having surface gradients

exceeding IO% as determined from

maps at scale 1:250,000.

Areas having drainage densities averaging at least two 10 ft. deep

drainages measured parallel to contours, as determined from maps at

scale of 1:24,000.

SOURCE U S Air Force SOURCE. U.S. Air Force
60 . MX Missile Basing

subsequently evaluated on the basis of distances from coasts (to reduce the potential

effectiveness of sea-based forces), distances

from national borders (to reduce vulnerability

to “unforeseen threats”)* as well as compatibility with local activities and the sense of

Congress that the basing mode for the MX

missile should be restricted to location on the

least productive land available that is suitable

for such purpose. ”

Figure 31 indicates the areas of geotechnically suitable lands identified by the Air

Force.

Of these areas, the Great Basin of Nevada

and Utah and the Southern High Plains of west

Figure 31 .—Geotechnicatly Suitable Lands

(

) ~

t’u

i MM Wing VI

/ ’

\

.——. —

)

)-J ‘ ‘ – – –

/

I I

\ -

/

I

Northern Weat Plains

- > - Wheatgrasa-Needlegraaa-BIU@em 1

Mojave

and Jo

 White Sands

Scale

o 100 200 300 400 Miles

O 100 200 300 400 500 600

Kilometers

New Mexico Semidesert Grassland w \

Trans. Pecos Chihuahuan

Shrubsteppe

SOURCE U S Air Force u
Ch, 2—Multiple Protective Shelters ● 6 1

Texas and New Mexico were identified as the

onIy “ reasonabIe risk” areas, and the Nevada/

Utah location was selected by the Air Force as

the preferred area for MX/MPS.

Table 6 indicates the “candidate areas”

identified by the

predominant vege

region.

Air Force along with the

ative characteristics of the

Roads

The MPS will have a substantial

work of approximately 8,000 miIes.

The designated transportation

road netnet work

(DTN), consisting of paved asphalt roads, 24-ft

wide with 5-ft shoulders, wil I connect the

assembly area with each cluster, and will total

between 1,300 and 1,.500 miles. Inside each

cluster will be roads connecting alI the shelters

and the cluster maintenance facility. About

6,200 miles of these cluster roads will be constructed, 21 -ft wide with 5-ft shoulders Iders. These

roads will be unpaved and treated with dust

suppressant, and are designed to support the

missiIe transporter. Large earth berms will prevent movement of the transporter between the

DTN and the cluster roads. In addition, some

1,3oO miles of smaller support roads in the

cluster area will be built to connect shelter

clusters and support SALT-related activities,

Figure 32 illustrates the construction profiles

of the different roads.

Physical Security System

The Air Force has examined two basic systems for MPS security: area security, invoiving

restricted access and continuous surveiIlance

of the cluster areas; and point security, involving restricted access only to the missile

shelters, command facilities, and other military facilities. Figures 33 and 34 compare the

configurations of point and a red security

systems.

Under area security, each cluster of shelters

would be bordered by a warning fence and

posted notices. Only authorized personnel

would be permitted in the posted area, and

their movements would be continuously monitored by remote surveiIlance. Security forces

would be available at all times for dispatch to

unauthorized intrus ions. To prevent the implantation and operation of sensors from aircraft, the airspace over the deployment area

would also be restricted to an altitude of 5,000

ft, and controlled to an altitude of 18,000 ft

(i.e., a permit would be required).

Under the point security system, each missile shelter would be surrounded by a fenced

area of 2.5 acres, and only those 2.5-acre sites

and necessary military facilities would be excluded from public access. Although the cluster roads would be separated from the paved

DTN roads by earth berms to prevent movement of the missile transporters, the berms

Table 6.—Candidate Areas

Population Private land

Area State Ecosystem Urban Rural ownership

Great Basin NV/UT Desert shrub/sagebrush/range 4,922 1,215 <10%

Mojave Desert CA Desert shrub/range 51,811 21,980 < 10%

Sonoran Desert AZ Desert shrub 77,670 13,183 10%

Highlands AZ/N M/TX Semidesert grassland/desert shrub 57,361 9,449 >50%

Southern High Plains TX/NM Plains/rangeland 83,921 15,504 950/0

Central High Plains CO/KA/NE Mixed grass prairie 54,479 15,123 >9570

Northern Great Plains MT/ND Mixed grass prairie Unavailable Unavailable

SOURCE U.S Air Force
62 ● MX Missile Basing

Figure 32.— Road Construction Profiles

Roads

Designated assembly area

Protective

shelter

k

,,,1.*

. --

I \

I

1

\/

P

5’0” Shoulder 1 r

5’0” Shoulder

,1 , 24’ ,tI

I I I I

it . .

& I ‘Ust Pa’’’ ave+e+ :

Aggregate base~

J

~COmpacted fill

Bituminous surfacing

Designated transportation network (paved)

5’0” Shoulder

1 r

5’0” Shoulder

i

I I , )4 ‘

I I

21 ‘-30’ I 1

I I

I I

I t

/

Dust palliative I I

I I

- — -

~ j

- -

Existing groundline

Aggregate base

Cluster road (unpaved)

5’0” Shoulder

7

; - 10’-20 ’

J 1

5

’

0

’ ’

sh0 u

’

d e r

I 1

I 1

I I Dust palliative I ~

I I

#

1

1 I I

I

Existing groundline ~

J

~ Compacted fill

Aggregate base

Support roads (unpaved)

SOURCE U.S Air Force

would be otherwise passable and the public ● four area support centers

would have nominally unrestricted access to

all unfenced portions of the deployment area.

To accomplish this task, the physical security system would include the following safeguards and activities in the deployment area:

● jntrusion sensors and access monitors a t

the (unmanned) shelter sites and cluster

maintenance faciIities,

● a large number (2,300) of smalI radars for

cluster surveillance,

that would

house helicopters for 30-minute response

time to cluster-area sensor alarms, and

. roving ground patrols of 20 two-man

teams.

Because there would be unrestricted ground

movement, there would also be no restrictions

on airspace.

The manning estimate for security police,

that includes deployment area patrols, area

support center, helicopter crews, and base per-
Ch. 2—Mu/tiple Protective Shelters ● 63

Figure 33.— Area Security

Fenced area \

4 ,

n fenced

deployment 

region

\

\

Fenced area

SOURCE U S Air Force

Figure 34.— Point Security

Explosive Restricted

/

Unfenced

SOURCE U S Air Force

sonnel is about 2,300, or about 25 percent of

the entire manning estimate. This percentage is

simiIar to that at the Minuteman wings.

At the same time, unrestricted public access

to the deployment area would require increased security measures to counter against

portable or emplaced sensors. Attempts would

be made by the security force to deter persons

who might be involved in planting sensors for

missile detection, attempting to penetrate the

sites, or sequentialIy visiting a number of

shelters. Such measures also might include

escorts accompanying al I transporter movements, and would, presumably, include frequent “security sweeps” to detect implanted

sensors.

Furthermore, it is likely that additional controls would have to be exercised on activities

within the deployment area. The Air Force has

stated that restrictions on public use of the

deployment area would not be necessary, and

that ranching and mining activities could proceed “up to the fences. ” However, mineral exploration and mining activities pose problems

for PLU security, For example, modern geological exploration and development utilize

sophisticated electronic equipment, and test

for the same types of chemical, electrical, and

magnetic signatures as would be associated

with the MX missile. I n the event that potentially detectable differences exist between MX

missiles and the decoys, unrestricted uses of

geologic testing equipment would pose security threats,

Increased traffic due to the necessity of

security sweeps to protect against the covert

implantation of sensors in the areas surrounding roads and shelters wou Id, however,

substantially increase impacts on the physical

environment.

President Carter decided against the use of

an area security system and directed the Air

Force to proceed with point security in 1979,

The Air Force presently believes that area

security wouId be infeasible and unnecessary,

Nonetheless, OTA’S assessment of the tech-
64 ● MX Missile Basing

nical problems associated with PLU suggests

several implications for the security system requirements of MPS. First of all, it is possible, as

the Air Force maintains, that engineering solutions to the problems of missile and decoy

similitude will permit point security as

planned. Alternately, as has been noted, it is

possible that problems of PLU technology will

make MPS vulnerable to detection regard les<

of security measures. Thirdly, it is possible that

weaknesses in PLU technology could be offset

by an area security system. Finally, it is possible that uncertainties in PLU technology

would warrant operational restrictions on

public activities within the deployment area,

but outside the fenced exclusion areas established for point security, If Federal lands are

used, this possibility raises questions regarding

public access to public lands. For example,

mineral explorations that utilize highly

sophisticated techniques and equipment for

the measurement of magnetic, gravitational,

geochemical, and seismological characteristics could pose threats to PLU security if

they involved the systematic coverage of areas

containing many shelters. Livestock operations

couId be affected by routine PLU activities

(such as security sweeps during calving

season); and any interference with livestock

operations or mineral activities could lead to

Iitigation claims.

Land Use Requirements

addition to this land, however, 60 mi2 of land

W ould be required for support facilities and

122 mi2 would be necessary for roads. The

total land area defined by the perimeter of the

individual clusters would be approximately

8,000 mi

2

, and the total deployment area

wouId be in the range of 12,000 to 15,000 mi2.

Figure 35 illustrates the relation of individual clusters to the basing area.

Under a point security system, only the 1 9

m i

2 of missile shelters, maintenance facilities,

and operating bases would be fenced and excluded from public access. Otherwise, it is Air

Force policy:

to guarantee civilian access to all but

the fenced portions of the MX deployment

area. This means that c iv i I i ans wiII have

essentialIy the same access priviIeges to

the deployment area that they have

aIways had. AgricuIture can take place

right up to the shelter fences, and camping, hunting, and mining can continue

without hindrance by the Air Force.

A potential confIict with this policy exists to

the extent that Department of Defense safety

regulations would require a safety zone of

approximately 1 mi2 around each missile

shelter; but this reguIation would only Iimit the

construction of habitable structures within the

safety zone, and waivers could be sought for

temporary structures necessary for mining or

geologic exploration.

Thus, the total land requirement for MPS

wouId involve an area of 12,000 to 15,000 mi2

for the baseline system, of which 8,000 m i

2 or

more wouId be restricted from public access

under an area security system, and less than 35

mi 2 wouId be restricted from public access

under the proposed point security system, I n

either event, however, approximately 200 mi2

of land would be converted from existing

range to missile sites, roads, and operating

bases.
Ch. 2—Multiple Protective Shelters 65

Figure 35.— Hypothetical MPS Clusters in Candidate Area

Carson

City

\

\

\

I

. - l

\

—

I

I

Las Vegas

I I

SOURCE U S Air Force

I n the proposed deployment area of Nevada

a n d U t ah, virtually all of the lands involved

wouId be federaIIy owned Iand under rider the jurisdiction of the Bureau of land Management

of the Department of the Interior (BLM) and

use of the Iands for MPS would require congressional action pursuant to the Engle Act (requiring congressional review of land withdrawals i n excess of 5,000 acres for miIitary

purposes) Additionally, pursuant to the

Federal Land Policy and Management Act, the

Secretary of the Interior would have to approve permits for rights-of-way or withdrawals

for roads, raiIways, pipelines, powerlines, and

other construction-related activities.

In the event that non-Federal lands might be

used, it wouId be necessary to acquire these

lands through lease, purchase, easement, or

condemnation. I n either case, however, provisions would have to be made for the initial

withdrawal of lands substantially in excess of

the minimum requirements, to allow site-specific engineering studies and flexibiIity i n final

siting determinations for shelters, roads, and

permanent facilities.

In its simplest form the implications of these

land use requirements are twofold. First, the

necessary withdrawal of lands, whether temporary or in perpetuity, and whether of private

lands or public lands, will require the negotiated settlement of a wide variety of property

claims and constitutionally protected rights. In

the proposed basing area of Nevada and Utah,

these claims would include patented mining
66 MX Missile Basing

claims (that are defined as legal property

rights), oil and gas leases, BLM grazing permits,

water rights, and Native American land rights;

all of which are potentialIy Iitigious matters.

BLM Grazing Permits

In the case of BLM grazing permits, for example, BLM has authority for the integrated

management of Federal range resources under

the Taylor Grazing Act of 1934. The carrying

capacity of the lands is defined in terms of

animal unit months (AU MS, or the amount of

forage needed for the complete sustenance of

a single cow or horse or five sheep or goats for

a single month). Allotted grazing rights are

determined on the basis of the relative carrying capacities of private and public lands.

Thus, the market value of private lands is tied

to allotments for Federal land grazing permits,

that are in turn defined by the carrying capacity of the land. The Air Force has estimated that

MPS would affect less than 1 percent of the

allotted AUMS in the proposed deployment

area by dividing the total deployment Iand

area (20,000 m i 2, by the amount of area removed from use (200 mi2). In fact, however, the

lands removed from use would be drawn largely from the prime grazing lands between the

bottomlands and benchlands of the valleys.

Even if it were to be assumed that there would

be no impacts on the range land beyond those

200 miz directly removed from use, it is clear

that the effects on livestock operations would

be disproportionately great, and the value of

private ranchlands would be diminished as a

result. Similarly, these claims would be complicated by any effects of MPS development

on the water rights that are integrally related

to the carrying capacities of both the public

and private lands.

Oil and Gas Leases

Although legally distinct, both oil and gas

leases, and hardrock mining claims, pose

similar institutional problems. Under the

Mineral Leasing Act of 1920, Federal lands

were made available for oil and gas exploration and development. Significant oil and gas

leasing occurs in the proposed deployment

area and estimates of the potential reserves

within the overthrust Belt that cuts through

many of the canal idate areas suggest the potential for greatly expanded exploration and development within the next decade. The Air

Force policy clearly is intended to permit virtually unimpaired oil and gas exploration; but

constraints on activities resulting from PLU restrictions could result in Iitigable claims.

Hardrock Mining Claims

‘Similary, MPS security requirements could

result in litigiable claims based on hard rock

mining activities. Unlike oil and gas activities

on the Federal lands, that are leased rights,

hardrock mining claims under the 1872 Mining

Act are patent claims; i.e., legal title of the

public lands are transferred by Government

deed into private ownership. As such, patented

mining claims create private property interests

that are compensable, and to the extent that

conflicts arise with MPS construction and operations, these claims wouId have to be settled. Unpatented mining claims present similar

problems.

The problem of mining activities is particularly significant because current activities

within the proposed deployment area include

gold, silver, copper, molybdenum, uranium,

fluorspar, barite, alunite, and beryllium; and

exploration activities for new deposits utiIize

state-of-the-art sensing equipment for detection of physical anomalies essentially the same

as those involved in PLU discrimination.

Native American Claims

There are a number of complex Native

American issues that are related to the proposed Nevada-Utah basing area, probably the

most significant of which is the land claim of

the Western Shoshone. The Western Shoshone

claim that much of the land in the Great Basin

was never ceded to the United States and rightfully still belongs to them pursuant to the Treaty of the Ruby Valley, This claim could be settled in many ways ranging from a cash settle-
Ch. 2—Multiple Protective Shelters ● 6 7

ment to establishment of a new reservation,

but failure to resolve the matter (which is currently In the courts) couId leave a cloud on presumed Federal ownership of the proposed deployment area.

Other Indian land claims involve the designation of a future reservation for the recently created Paiute Indian Tribe of Utah (resulting from the amalgamation of severa l

Southern Paiute bands and their restoration to

a trust status in the 96th Congress), and possible disruption of the small Moapa Reservation

(Southern Paiute) and Duckwater Reservation

(Western Shoshone). Disruption of Indian

water rights couId also lead to Iitigable claims,

and the desecration of sacred ancestral lands

would clearly violate the protections of the

Native American Religious Freedom Act

Water Availability

In the arid lands of the West, water availability is a controversial issue for all growth

and development: first, because the physical

availabliity of water is Iimited; second, because physicalIy available water may be unsuitable for proposed uses; and third, because

Instltutional requirements for water rights are

compIex and often ambiguous

In the case of MPS, relatively high-quality

water would be required for construction activities such as concrete preparation, revegetation, and domestic uses, and lower quality

water could probably be used for aggregate

washing, equipment cooling, and dust control.

The Air Force has estimated the total water

consumption of MPS baseline between 310,000

and 570,000 acre-feet including construction,

and a 20-year operation I period, with a peak

demand of 45,000 acre-feet per year (AFY) in

the late 1980’s and an annual requirement of

15,000 to 18,000 AFY during operations.

These estimates include requirements for

the deployment area, operating bases, transportation systems, support facilities, irrigation

of shelter sites and domestic uses of the work

force, but do not include additional water for

reveget at ion of other disturbed lands or estimates of larger work force populations. In

terms of other large-scale projects, these re

quirements are roughly comparable to the re

quirements of large-scale coal-fired powerplants, that require about 10 AFY/MWe, and

synthetic fuel plants, for which estimates of

proposed facilities run from 4,000 to 20,000

AFY.

For the purpose of minimizing conflicts with

existing water users, the Air Force has proposed using unallocated deep ground water reserves and has conducted preliminary tests of

ground water resources. However, the use of

deep water reserves poses several problems. In

the proposed basing area of Nevada and Utah,

the interbasin geology and hydrology is so

complex that neither the resources of the deep

acquifers nor their relationship to existing surface waters can be known with precision.

Therefore, if ground water resources are utilized, effects on surface water and existing

al locations would be difficult to predict. It is

apparent, nonetheless, that if ground water resources are utilized, certain impacts and tradeoffs will be involved:

in some areas, water tables would be

lowered and both the energy requirements

and the costs of pumping water would be

i n creased;

surface seeps, streams, and wetlands

might be reduced or eliminated, thus affecting livestock, habitat, and dependent

species;

dislocation of existing surface and ground

water rights could be extensive and lead

to subsequent litigation; and

particularly serious water shortage problems and conflicts with prior users appear

likely in the vicinity of the proposed

operating base at Coyote Springs.

Moreover, uncertainties regarding these problems are compounded by the fact that shortcomings in monitoring and recordation yield

only approximate figures in water depletion

and water rights.

On the other hand, if the estimated needs of

MPS are compared to the existing surface

water allocations of the proposed deployment
68 ● MX Missile Basing

area, it is apparent that sufficient water exists

to accommodate the proposed baseline system. In comparison with an estimated annual

water requirement of 15,000 to 18,000 AFY for

operations and 45,000 AFY for peak year construction, there are 900,000 AFY of currently

allocated water rights in the deployment area,

and an estimated 300,000 AFY are allocated

for future energy and mineral development,

(See tables 7 and 8.)

Because the economic value of water is substantially greater for synthetic fuels and

energy development than regional agriculture,

proposed energy projects have been able to

purchase necessary water rights from willing

selIers (as in the case of the Intermountain

Power Project scheduled for construction in

Delta, Utah, for which rights to 40,000 AFY

Table 7.— Water Required for MX

Acre-feet 

Year Construction Operation Total

1981

1982

1983

1984

1985

1986

1987

1988

1989

1990

1991

1992

1993

1994

2000

168

1,247

6,807

19,075

26,744

38,614

37,653

26,744

12,906

3,731

2,152

761

262

0

0

0

165

510

1,781

3,760

6,405

9,545

13,925

17,615

20,166

20,166

20,166

20,166

20,166

20,166

168

1,411

7,317

20,857

31,825

45,018

47,199

40,669

31,464

23,585

22,319

20,928

20,475

20,166

20,166

SOURCE Air Force figures Include DDA, OB, transportation system. support fa

Cilities irrigation of shelter sites, and domestic uses for operations

personnel and their dependents

Table 8.—Water Uses

Irrigation 827,223

Livestock 2,514

Energy and minerals 65,330

Urban/industrial 13,593

Total 908,660

Future energy and minerals (period not indicated) 297,074

SOURCE MX Siting Investication Water Resources Program Industry Activity

Inventory Nevada. Utah, Prepared for U S D A F BMO/NAFB, by

Fugro National, Inc ,02, September 1980

have been purchased). Presumably the Air

Force would be able to find willing sellers

with in the MPS deployment area.

“The United States could acquire existing

water rights by eminent domain (condemnation) if Congress were to authorize such actions. However, even if existing land and water

rights were not condemned, it is possible, given

the scope of MPS requirements, that landowners, lessees, grazing permitters, and

holders of existing water rights could contend

that their rights had been either “taken” (and

file claims for fair and just compensation), or

“ injured” (resulting i n a legal claim for damages based on tort and trespass law).

on the other hand, OTA’s assessment indicates that ranching (and possibly mining) operations in the proposed basing area would

probably close down in response to economic

pressures, impacts on rangelands, and possible

PLU restrictions resulting from MPS development. Moreover, the laws and regulations of

both Nevada and Utah provide for the transfer

of water rights on either a permanent or

limited-term basis. For this reason it is likely

that water would not be a limiting factor for

MPS deployment unless it were necessary to

construct more than 4,600 shelters or additional water was necessary for revegetation efforts. The issue of revegetation, however, is extremely controversial and pivotal to many of

the physical impacts of MPS basing. Air Force

estimates of water requirements include some

water for revegetation of the missile sites, but

no water for revegetation of disturbed lands.

Since there are no established methods for

revegetation of arid lands without substantial

irrigation, the total water required for reVegetaion couId far exceed al I avaiIable resources within the deployment area. Assureing

an irrigation requirement of 1 AFY/acre, more

than 3 million acre-feet could be necessary

based on OTA’S calculations of possible land

use impacts.

Physical Impacts

Any large-scale construction projects involve physical impacts that are dependent on

site-specific characteristics of the area. Con-
Ch. 2—Mu/tip/e Protective Shelters 6 9

struction generalIy necessitates direct physical

impacts on the soils, vegetation, Iivestock,

habitat, wildlife, water quality, air quality, and

other environmental characteristics of a

region The severity of these impacts depends

on their particular characteristics and their

magnitude, on the abiIity of the ecosystem to

adapt and recover from disturbances, and on

values subjectively placed on the changes that

occur I n the case of MPS basing, the expansive grid-pattern of the system, the magnitude

of the land-use requirements, and the utiIization of lands that have inherently limited

capacity to absorb and recover from disturbances, could lead to widespread desolation of

the deployment areas

The Air Force baseline proposal has been described as the largest construction project in

the history of man, and it would involve, at a

minimum, the disruption of 200 m i

2 of land for

missiIe shelters, roads, and operating bases, as

wet I as additional lands for temporary construction camps, haul roads, gravel pits, holding areas, and other construction related activities. I n the absence of irrigated revegetation, or the presence of prolonged drought, the

likelihood of these impacts would increase,

possibly causing fugitive dust from decertified

lands to contribute to drought conditions that

couId affect agricuIturaI productivity outside

the boundaries of the deployment area

As indicated above, MPS basing requires a

large deployment area, with a minimum of

4,600 shelters spaced at 1 to 2 mile intervals

connected by 6,000 to 8,000 miIes of roads

throughout a geographic area of 12,000 to

15,000 mi2 The construction of these facilities

wouId directly disrupt at least 200 mi2 of land

surface: but because arid or semiarid lands

would be required and the impacts would be

spread over a grid rather than confined to a

bounded area, the attendant impacts could

spread significantly.

Impacts on Soils and Vegetation

The native vegetation of arid lands is necessarily highly specialized and inherently

fragile, resistant to drought but vulnerable to

the impacts of physical disturbance and vehicular traffic. Throughout the arid and semiarid

lands of the West, including the proposed

deployment area and most of the geotechnically suitable candidate areas, “invader”

species such as Halogeton and Russian Thistle

have colonized rangelands rapidly following

the physical disturbance of lands and the

removal of native vegetation. These invader

species offer protection against further deterioration of the soils by agents of erosion,

but the protection is of Iimited value insofar as

Halogeton does not provide nutritious forage

and may be toxic to Iivestock. “Complete recovery (of disturbed lands), ” the Air Force has

stated, “may take a century or more Long

term establishment of Halogeton could prevent reestablishment of native vegetation, and

i reversibly degrade the value of vegetation for

future wildlife and Iivestock use.’”

Alternately, if not colonized by Halogeton

or other “invader” species, the arid, loosepacked soils are vulnerable to structural disruption or compaction When compacted the

soils increase the frequency of water runoff

and sheet-wash erosion, and when disrupted

the loose particles become susceptible to wind

erosion. I n either case, the effects of erosion

further degrade the land by altering both the

physical and chemical profiles of the soil, and

by impacting adjacent lands through the

alteration of water flows and the abrasion of

airborne particulates. Because arid lands generalIy have relatively low levels of biologic activity, soils are slow to reform, native species

are slow to return, and the alterations of the

land are likely to be irreversible without substantial human intervention.

The implications of these processes are of

particular concern for MPS deployment because of the scale of the project and the potential for “spill-over” effects.

Although the Air Force claims to have been

successfuI in confining the impacts of MPStype construct ion act ivities to designated

areas on test ranges, they have indicated that

“a corresponding degree ot succes wiIl pro bDeployment Area Selection Land Withdrawal Acquisition
70 . MX Missile Basing

ably be u n Iikely (in the case of MX MPS) due to

the magnitude of the project, ” { and th e

amount of disturbed land is Iikely to increase

throughout the c-obstruction stage whiIe add itionaI lands wouId be disturbed atter construct ion as a consequence of off-road vehicle use

a n d continued erosion q

Thus, the Air Force has indicated that in the

absence of mitigation, “the significant adverse

impacts from vegetation clearing would range

from long-term to permanent, 5 Both as a result of the magnitude of the project and the

particularly large interface between disturbed

lands and undisturbed lands, the potential impacts could spread far beyond the 200 mi 2

directly disturbed by construction of the missile shelters, roads, and support facilities. The

DE IS indicates that “the large number of

cleared areas would result in a greater impact than would occur from the clearing of

only a few such areas, ”6 and “the more disturbed area, the larger the amount of vegetation lying around the perimeter of the cleared

areas which wilI be subject to erosion and

f looding ’” Consequently, the Air Force estimated that vegetative clearing and the associated secondary impacts of construction activities could extend up to 0..5 miles from

points of direct disturbance. Although this

figure was considered in the DE IS only as

“rough index, ” it clearly indicates the potential for extensive disruption of the deployment

area,

If a vegetative disturbance area of only 0.25

miles from directly impacted lands is assumed,

the construction of 8,000 miles of roads could

resuItin devegetation of 4,000 m i2 of land; and

if a perimeter of 0.25 miles around each of the

4,600 missile shelters is considered, an additional 500 to 1,000 mi2 of land could be lost

(depending on overlaps with the impact zones

of the roadways). Figure 36 i Illustrates this

issue.

On this basis, 5,000 mi2 of productive rangeIands could be lost in addition to lands impacted by operating bases, construction

camps, haul roads, gravel pits, other construction related activities, and secondary development resulting from the population influx

associated with MPS construction and deployment. If the impact perimeter is increased to

0.5 miles, as considered in the DE IS, the

baseline system could impact 10,000 mi2

. And

if it is assumed that the “periodic sweeps” required by PLU activities would be concentrated in roughly the same land areas within

0,25 or 0.5 miles from MPS roads and missile

shelters, then, as we have indicated, the im

-

pacts could be permanent.

To mitigate these impacts the Air Force has

proposed a variety of measures, including the

reapplication , of surface soils where subsurface soils are of lower quality; stabilizing

slopes; securing mulches; planting vegetation;

“minimizing) repeated disturbance of planted

areas from livestock and off-road vehicle

(ORV) activity until vegetation is adequately

reestablished;” and irrigating planted areas

that receive less than 8 inches of rainfall per

year.

These last two mitigation measures are particuIarly important, not only because of their

value to successful revegetation, but also

because of the impacts they suggest on

ranching operations, water requirements, and

the costs of MPS deployment, As the Air Force

not es:

Planting efforts usually fail in areas which

recieve less than 8 inches of precitation annually (which includes roughly 80 percent of

the projected disturbed area), unless irrigation

is used Revegetation water is not incIuded in

water estimates presented in this report [EIS]

and would increase requirements significantI\/ q

In fact, if 1 AFY/acre is required for revegetation, and 5,000 mi2 of land is disturbed by construction and secondary impacts, successful

revegetat ion would require more than 3 million AFY. Even using much more conservative

9 4-99
Ch. 2—Multiple Protective Shelters ● 71

Figure 36. —Potential Vegetative Impact Zone

SOURCE Off Ice of Technology Assessment

assumptions, the DEIS notes that “a comprehensive revegetation program would be

very expensive. 10

These potential impacts of MPS development are especially significant in the context

of western regional development. During the

past decade, expanded energy development

and population growth have greatly increased

+

‘“1 10 Ibid

pressures on the physical environment to the

point where they may be straining the region’s

life support systems and there is increasing

concern about the potential spread of desertification throughout the region. Desertification generally refers to the degradation of arid

lands to the point where they can no longer

support Iife, and it tends to break out, “usually

at times of drought stress, in areas of naturally

vulnerable lands subject to pressures of land
use. ” 11 Estimates of U.S. lands vulnerable to

desertification range from 10 to 20 percent of

the continental United States, and the President’s Council on Environmental Quality recently warned that the threat of continued desertification couId have “far-reaching implications in terms of the Nation’s food and energy

supplies, balance of payments, and its environ merit. ” 2

Symptoms of desertification are

already present throughout many parts of the

arid and semiarid West— including overdraft

of ground waters, salinization of topsoils and

waters, reduction of surface waters, unnaturally high erosion, and desolation of native vegetation 13 — and projected expansion of Western energy resources will involve continued

pressures throughout the region during the

next decade.

In this context, any number of alternate impact scenarios, inciuding expanded resource

development, rapid population growth, offroad vehicle traffic, or prolonged drought conditions, could contribute to increased desertification: but MPS in arid lands, because of

the magnitude of its grid configuration, clearly

poses the greatest potential threat.

Weather Modification

Desertification within the deployment region also raises questions of potential atmospheric effects that are highly speculative

at this time, but which, because of their potential implications for domestic agricultural productivity, deserve attention.

The Air Force has calculated that “fugitive

dust” emissions from MPS construction (based

on 200 mi of land disturbance) would result in

tenfold to twentyfold increases in atmospheric

particulate, and violations of standards promulgated u rider the Clean A i r Act, These em issions wouId degrade air quality over a wide

area (including several national parks), and

there is a possibility that health problems

could result from spore-laden dust churned up

from the desert soil,

other concerns, however, are suggested by

recent studies of atmospheric particulate that

suggest that climatic effects may result from

increasing aerosols of fine particulate in the

lower atmosphere. While the back scattering of

solar energy tends to decrease total atmospheric heating and thereby cool the lower atmosphere, absorption of radiant energy by particulate matter tends to increase the temperature while simultaneously acting as condensation nuclei that adsorb moisture and retard cloud formation. The net result of these

effects, depending on their relative magnitudes and a variety of other considerations,

C OuId be to increase temperatures in the lower

atmosphere and decrease precipitation. Moreover, these effects may be most Iikely in arid

regions, as evaporation from moisture in more

humid climates would tend to offset the increasing temperatures brought about by absorption of radiant heat.

The long-distance transport of fine particulates from desert regions of the world has

been well-documented, but the potential ef -

feel-s of resulting climatic alterations are

unknown. I f a causal relationship exists between fugitive dust emissions and downwind

weather mod if i cation, extensive fugitive dust

emissions from MPS deployment in the Great

Basin could have substantial economic impacts on agricultural productivity outside the

deployment area; and as in other matters discussed in this section, drought conditions

during the construction period would exacerbate the potential threats.

Least Productive Land s

Finally, in considering the physical impacts

of MPS basing, it shouId be noted that the

Department of Defense Supplemental Appropriation Act of 1979 included “the sense of

Congress that the basing mode for the MX missile should be restricted to location on the

least productive land available that is suitable

for such purpose. ”14 Accordingly, the pro-
Ch. 2—Mu/tiple Protective Shelters ● 73

posed deployment area in the Great Basin of

Nevada and Utah reflects this criteria, It is not

the /east productive land among the ,geotechnically suitable areas; but it is among the

least productive, and is considerably less productive than the High Plains regions that extend from Texas and New Mexico up through

Colorado and Nebraska to Wyoming,

However, the more productive agricultural

lands have an inherently greater capacity to

absorb the impacts of construction activities

and, in contrast to the Great Basin, could be

revegetated with relative confidence. For this

reason, the totaI amount of land lost to agricultural productivity might be considerably

less than in areas where revegetation is more

difficult. If it is assumed that 200 mi of {and

wouId be lost in a grassland ecosystem and

that the market value of crops is $80/acre/yr,

then the total economic loss associated with

this basing option would be approximately

$10.2 million per year. And if twice as much

land would be lost to agricultural productivity

in the Great Basin, with the market at approximately $5/acre/yr, then the net agricultural

loss would still be less than 10 percent of the

lost crop value in a grassland ecosystem.

Based on this rough estimation, 3,200 mi’ of

rangel and would have to be lost to equal the

lost agricultural value of 200 mi2 of crop land.

Thereforer if the impacts of MPS construction can be confined to the designated areas

during construction, and mitigation measures

are not very expensive, the economic costs of

deployment in “least productive lands” would

appear to be considerably less than i n more

productive croplands. But if it is assumed

either that the impacts will spread in arid

lands, or that mitigation measures to prevent

the spread of impacts will be more than $10

mill ion per year, the economic costs of “ least

productive lands” are Iikely to be at least as

great as the costs of using more productive

lands 
74 . MX Missile Basing

larger populations (at least 10,000-25,000 people) have the capacity to absorb greater population influxes without suffering adverse affects. To the extent that infrastructures of

housing stock, schools, roads, sewers, health

care facilities, and administrative services all

exist prior to rapid growth, these facilities

often can absorb much of the population increase, and the marginal costs of expanding

services and facilities are relatively small.

Insofar as the Air Force siting criteria for MPS

exclude areas with cities of more than 25,OOO

people within 20 miles, adverse socioeconomic

effects wouId be essentiaIIy unavoid able

Based on recent experience with Western

energy resource development, these i m pacts

wouId include a restructuring of the local job

economy as new jobs are created and existing

residents change jobs in hope of new opportunities and higher wages; changes in the lifestyle of relatively isolated and closely integrated communities; inadequate housing,

roads, sewers, schools, health care facilities

and administrative services; regional wage and

price inflation; and increased stresses on individuals, families and communities. It is also

worth noting that local residents are usually

unable to compete successfully with new

migrants for skilled labor positions and higher

paying jobs, and that few new jobs go to unemployed residents of the area, fewer still to

women and minorities, and virtually none to

Indians.

As a consequence of the influx of new

migrants with a relatively high proportion of

well-educated or skilled laborers, competition

for jobs does not always benefit existing community residents. Existing businesses are often

unable to compete with the higher costs of

wage and price inflation; new small business

operations are frequently unable to compete

with the high capital costs and risks associated

with meeting rapidly expanding business opportunities; existing residents may resent the

influx of new residents and associated changes

in community lifestyles; incoming residents

often find adjustment to reduced levels of

social services and amenities difficult; and increases in alcoholism and child abuse tend to

appear as manifestations of these increasing

community pressures.

Finally, in the isolated ranching, mining, and

farming communities of the Western States,

social ties between families and neighbors

tend to be especially strong, and both administrative government and the provision of

social services may be deeply rooted in informal community mechanisms. This relationship is true in general throughout the isolated

communities of the Western States, and it is

particularly true of the Mormon communities

of southern Utah, in which the integral relationship between church, family, and community wouId be profoundly disturbed by the

infIux of a large number of migrants who could

not be assimilated into the fabric of this

cu It u re.

These issues are complicated by the fact

that the Western States are in a process of

rapid growth and transformation, and that virtually all of the available Iiterature has been

drawn from experiences with western energy

resource developments that have been relatively large in relation to the existing community sizes, but that are relatively smalI in

comparison with the manpower requirements

and geographic expanse of MPS. In contrast to

large-scale coal-fired powerplants and synthetic fuel facilities with construction work

forces of 2000 to 5,000 people, located at

specific sites that could be clearly defined in

relation to the surrounding communities, estimates of the baseline construction work

force for MPS range from 15,000 to 25,000 people; and the Air Force is considering the use of

as many as 18 temporary construction camps

spread throughout a geographic area of 15,000

m i

2 for construction of MPS, Furthermore,

there is evidence to suggest that in several instances the net impact of rapid growth on

small communities has been positive. Following the boom-bust cycles of rapid growth and

decline, the communities have readjusted to

lifestyles closely resembling preimpact conditions, but with the added benefits of expanded

facilities resulting from an increased population base,
Ch, 2—Mu/t/p/e Protective Shelters ● 75

Thus, it might be the case that individual

communities within the deployment area

might benefit from MPS deployment, or alternately, that the effects of MPS deployment

might be indistinguishable from the effects of

accelerated mineral resource and energy development in surrounding areas. I n general,

however, it appears that the residents of small

communities in the deployment area would be

unlikely to benefit from MPS development,

and probably would face the loss of existing

ranching and mining operations within the

area

At the same time, the larger urban areas on

the periphery of the deployment area would be

affected by MPS development in a totally different way Unlike small towns faced with

neither the administrative nor the financial

capacities to accommodate large-scale

growth, larger urban areas with these capabilities would be faced with uncertainties r e

-

garding the magnitude and the location of th e

growth that might occur. unlike large-scal e

energy developments in which clearly defined

locations for planned facilities reduce the

uncertainties of planning decisions to questions of timing, financing, and scale, the

magnitude of MPS and geographic dispersion

of the proposed development complicates

these issues substantially

In contrast to large-scale powerplant developments with construction work forces of

2'000 to 4,000 people, estimates of the onsite

work force required for MPS development

range from 15,000 to 25,000, and OTA’S analysis indicates that actual construction work

force requirements could be as high as 40,000

people In this case, the total population impacts of MPS could be in excess of 300,000

people Because regional economic impacts

are a function of the magnitude and distribution of the work force population and associated growth, and the range of possible population impacts is so great, it is worth looking at

the basis for these figures in some detail.

Work Force Estimates

The Air Force has estimated that MPS construction wouId require a peak construction

work force of 17,000 workers

Iation of slightly more than

period of overlap between

tivities and initial operations

and a total popu100,000 during a

construction acFigure 37 illustrates the approximate relation between the population of the construct ion work force, operating personnel, and their

dependents.

I n fact, these figures represent conservative

estimates By the time the DE I S had been prepared, the construction work force figures had

been revised upwards almost 40 percent* –

and they fail to reflect the uncertainties that

are associated with all of these estimates

Figure 38 illustrates the direct construction

work force estimates (including onsite and

“life support” labor) of the Air Force, the Army

Corps of Engineers, and joint Air Force/Army

Corps task force on manpower estimates. Figure 39 illustrates the relationship between on-

-—

‘ 1 he [)r,]t t f ni lronn~<’nt ‘I I I 11)1)<1( t \t ,Itt’nl{’nt on Artl,) ${JI(I(

t Ion w a ~ pu hl I >h(’d ,] 1( )n x m It h <In t’rr<] t ‘i iht’t~t M h I ( h ( ont,1 I n~’(j

re~’ I ~t’(1 work t or( (’ (>~t I m‘] t t~i h,1 itlci () n ,) I ( ) I n t t,1s k t [ ) r( t, { )t t h(’

Figure 37.—Construction Work Force, Operating

Personnel, and Secondary Populations

110 I

I

Direct and

indirect

personnel +

dependent

(1000s)

100 “

90 —

80 —

70 —

60 —

50 —

40 —

30 —

20 — Construction

10 —

o

1980 1985 1990 1995 2000

Year

SOURCE U S AIr Force
76 ● MX Missile Basing

Figure 38.— Baseline Work Force Estimates

24

-

22 - Legend

20 -

— A C E

‘

o— A.F .

18

16

14

12 —

10 —

8 —

-

-

6

4 -

2

-

82 83 84 85 86 87 88 89 90

Annual average direct construction work force (including life support)

A. F./DElS 1,150 2,000 4,450 10,800 17,050 15,450 13,050

ACE 1,160 6,940 14,305 4,800

19,750 23,730 16,900 12,670

A. F.IACE 2,035 5,590 9,510 4,725

17,910 18,560 17,670 12,765 5,490

SOURCE A F /DEIS Chapter 1, Errata Sheet, Table 11

site construction labor estimates and estimates

of the total construction work force required.

Estimates of the costs and manpower requirements of major construction projects,

however, have characteristically underestimated actual costs and manpower needs. Evidence from various studies of this problem

suggests that these overruns resuIt in part from

revisions in engineering designs while construction is in progress, delays caused by late

deliveries of major components or bottlenecks

in materials supplies, and difficulties in utilizing manpower and materials efficiently on a

time-urgent schedule. Tables 9 and 10 provide

two indices of these problems. Table 9 indicates the average cost overruns in weapons

systems, public works projects, major construction projects, and energy process plants,

and table 10 compares the projected and actual manpower needs of large-scale coal-fired

powerpIants.

If all overrun factor of 73 percent is assumed

on the basis of the average manpower overrun

associated with coal-fired power-plants in the

West * the manpower estimates for MX/MPS

would increase to more than 42,000. As a I so

‘ The average manpower overrum from coal powerplants

I n the West is used here because it represents construction of a

known technology (rat her than a new” technology) in the arid

West Other projects such as nuclear powerplant or synthetic 

fuelplants involve higher degrees of new technologh development
Ch, 2—Multiple Protective Shelters ● 7 7

Figure 39.—Comparison of Onsite and Total Construction Work Force

26

24

22

20

18

16

14

12

10

8

6

4

2

Legend

— —— Construction onl y

Total “

.

.

\

●

.

/

\

●

● \

82 83 84 85 86 87 88 89

Year

Construction

only 1,832 5,031 8,559 16,120 16,700 15,900 11,490 4,941

Life support 203 559 951 1,790 1,660 1,770 1,275 549

Assembly and

check out o 400 1,000 3,550 6,000 6,000 5,900 5,750

Total 2,034 5,990 10,510 21,460 24,564 23,670 18,665 11,240

SOURCE Off Ice of Technology Assessment

Table 9.—Cost Overruns in Large-Scale Projects

Actual cost/

Type of system estimated cost

Weapons system ... . . . . . . . . . . 1.40-1.89

Public works. ., ., ... ... . . . . 1.26-2.14

Major construction ., ... ... . . 2.18

Energy process plants. . . . . . . . 2,53

SOURCE Office of Technology Assessment, 1981
78 ● MX Missile Basing

Table 10.—Estimated and Actual Construction an accelerated construction schedule and 73

Work Forces for Coal-Fired Powerplants percent to allow for manpower overruns. — -

- Estimated Actual Percent ‘

Plant (and State) peak peak change

Antelope Valley - Population Estimate s

(N. Dak.). . . . . . . . . . 840 1,370 + 63

Boardman (Oreg.) . . . 760

Clay Boswell (Minn.) 900

Coal Creek (N. Dak.). 980

Laramie River (Wyo.). 1,390

White Bluff (Ark.). 1,100

1,482

1,560

2,113

2,200

1,900

+ 83

+ 73

+ 91

+ 58

+ 72

Similar uncertainties affect estimates of the

secondary populations associated with the

construction work force. Assumptions must be

made regarding the ratio of new secondary employment (e. g., construction of new housing,

grocery stores, gas stations, etc., ) by MPS conFigure 40.—Construction Work Force: High-Range Projection

65

60

55

50

45

40

35

30

25

20

15

10

5

—

Legend: —

Baseline construction work force

PIUS 600/0

Plus 73 ”/0

●

●

●

✍

✎

●

●

82 83 84 85 86 87 88 89

Year

Baseiine

construction

work force 2,034 5,990 10,510 21,460 24,S60 23,670 18,666 11240

Plus SO% 3 a 9,884 16,816 34,336 39,296 37,872 29,864 17,964

Plus 73 ”/0 5,630 16,860 29,091 59,401 67,993 65,518 51,664 31,112

SOURCE Off Ice of Technology Assessment
Ch. 2—Mu/tiple Protective Shelters ● 7 9

struct ion and operations, and additional

assumptions must be made regarding the

demographic characteristics of the construction work force. Despite the fact that the characteristics of western energy project construe

tion labor forces have been studied, significant

uncertainties exist, and the popuIation impacts

of MPS couId vary considerably depending not

only on the number of construction workers involved, but the relative numbers of single and

married workers, and choices they make regarding residential locations and commuting

alternatives. Using the Task Force baseline estimate of construction work force size (see fig.

38), figure 41 illustrates the range of secondary

population growth associated with the base

case assumptions using three different sets of

demographic assumptions,

Finally, if these factors are considered in

conjunction with one another, a wider range of

population growth scenarios results. Figure 42

illustrates the range of possible population

growth scenarios resulting from alternate assumptions regarding the location and demographic characteristics of the primary work

Figure 41.— Range of Secondary Population Growth

#-- -

120 . Scenario 1

-- Scenario 3

 Scenario 5

/ ’

105

/

\

90 \

x

82 83

I I

Table 2 summarizes these data:

Scenario 1 3,404

(x 1 .73)

Scenario 2 2,839

(x 1 73)

Scenario 3 4,356

(x 1 73)

Scenario 4 2,493

(x 1 .73)

Scenario 5 2,174

(x 1 73)

1982

18,289

12,594

29,689

7,380

6,412

1983

Scenario 1 0511 single + 0.489 married

Scenario 2 0375 single + O 25 married +

Scenario 3, all workers married

Scenario 4. all workers single

Scenario 5 all workers shuttled

8 4 8 5 8 6

I 1 Year I

—

32,576 67,68 1 78,796

22,382 27,789 53,595

53,167 110,876 129,458

12,872 26,346 30,313

11 ,2?5 22,940 26,303

1984 1985 ‘-1986

0375 shuttled

87 88

I I

—.

76,949 62,035

51!917 41,895

126,668 102,449

29,371 23,313

24,629 20,070

1987 1988

89

I

38,699

25,944

64,333

14,169

12,127

198 9

SOURCE ERC p20/Office of Technology Assessment

“ /footnote from page 25

SOURCE Off Ice of Technology Assessment
80 . MX Missile Basing

Figure 42.— Range of Potential Population Growth

360

340 —

320 —

300 —

280 —

260 —

240 —

220 —

200 —

180 —

160 —

140 —

120 —

100

t -

80 —

60 “

40 —

20 / / —— ~ -

- - *

0

I I 1 I

82

- Accelerated construction;

73% overrun; all workers

married 12,057

Accelerated construction

50%0 married workers 5,446

A.F. base case; no overruns; all workers shuttled 2,174

83 84 85 86 87 88 89

 Accelerated construction;

73% overrun;

all workers married

Accelerated constructio n

50°/0 married workers

 A.F. Base case ;

no overruns;

all workers shuttled

82,179 147,166 306,904 358,339 350,617 283,578 178,073

29,262 52,121 108,289 126,072 123,118 99,256 61,918

6,412 11,225 22,940 26,303 24,629 20,629 12,127

SOURCE Off Ice of Technology Assessment

82 MX Missile Basing

Figure 43.—Cumulative Energy Activity in the West

SOURCE AbtlWest. 1981

neers, and experienced managers, is regarded

as highly mobile and projected to be in short

supply, the labor requirements of MPS construction could affect resource development

throughout this 10-State area. Training programs are underway to offset some of these

labor shortages in several States, but they are

unlikely to have a major effect on the shortages because many of the skiIled positions require training and experience (that are in turn

dependent on skilled instructors) and because

the clemand for labor changes rapidly with

construction plans and scheduIes.

System Schedule

The MX/MPS schedule is highly successoriented and requires specific actions by Congress if both IOC and FOC are to be achieved.

Given these actions and no major develop-
Ch. 2—Multiple Protective Shelters ● 83

ment problems, it is possible both dates can be

accomplished. In all probability, however,

some SIip in IOC shouId be expected. The current DOD review of basing options is delaying

actions required to ensure even a possibility of

meeting IOC Unless a timely decision is made,

Ieadtimes required will inevitably cause a

delay in achieving the IOC date.

Table 11 .—System Time Schedule

Land withdrawal application filed 7181

Legislation to Congress ., . 1/82

Legislation approva l 5182

SATAF activate d ,. 1182

Start construction to operating base 4182

Firstmlsslle test flight . 1/83

Misslesslle production contract award . 7183

DSARC III-missile . 7183

Start construction in deployment are a 1/83

First cluster available 8/85

Full base support available 9185

Initial operating capability 7186

SOURCE Off Ice of Technology Assessment

Most of the land required for the preferred

Air Force basing

location for MX/MPS is

Federally owned and under the control of the

Bureau of Land Management, Department of

the Interior (DO I) Transfer of the necessary

land to DOD requires congressional approval.

The schedule, as planned by the Air Force, is

predicated on a basing decision in June 1981,

and allows a public comment period between

July and October, with the legislative package

ready for congressional consideration in january 1982 Final approval and land availability

is scheduled for May 1982.

A June 1981 basing decision did not take

place while the Air Force and DO I are exploring means of expediting the withdrawal application process, the application must be

specific in terms of base and deployment area,

and both the land withdrawal application and

congressional enabling legislation will have to

address complicated issues such as the land

claims of the Western Shoshone and State

school lands in Utah. Slippage of the land

withdrawal action would impact all other

dates associated with base and deployment

area construction and Ieadtimes would also be

required to ensure adequate electric power

supplies, to purchase water rights where needed, and to obtain necessary permits, Although

it is difficult to assess the extent of slippage

likely to occur, it is doubtful that an IOC of

1986 can be met, and system costs would escalate along with any slippage in IOC, Foreseeable slippages could also impact FOC, although a slip in IOC would not necessarily delay final operating completion,

The missile deployment and production

schedule may also present some problems. A

production decision is scheduled early in the

flight test program, and, in fact, before the

missile-cannister-shelter tests take place. I n addition, long Ieadtime materials’ authorization

is scheduled to occur in February 1983, or 1

month after first flight and 5 months before

the production decision Problems in the flight

test program under these conditions could

lead to overall program delays, renegotiation

of production contracts, and, perhaps, substantially increased costs. It is also not clear

that the Air Force has the authority to release

contracts for long leadtime material before the

production decision is formalized

The countermeasures subsystem, both for

the missile and for the decoy system, also may

present scheduling difficulties Long Ieadtime

items for prototype systems were scheduled

for approval in April 1981. This has not occurred, and the delay wilI probably postpone

initial deliveries of prototype hardware and

impact on qualification tests and perhaps the

missile test program itself.

The formal submittal of a budget estimate

for funding deployment area construction is

scheduled for October 1981. This submittal

wiII include an update of MiIitary Construction

Program (MCP) costs based on the outputs of

the 1980 Systems Design Review a site-specific estimates of protective shelter cost.The

uncertaintaties introduced by the DOD review of

basing options tend to inhibit the deveopment

of background material and internal Air forceDOD review of the revised baseline estimates 

supporting the budget request Delays in the

basing decision may make it difficult for the

Air Force to adhere to the normal budgeting

scheduIe and prduce estimates with the degree of accuracy recuired red This problem wiII
84 ● MX Missile Basing

be intensified if the basing decision is other

than horizontal shelters in the Nevada-Utah

area

In OTA’S judgment, the IOC date is likely to

slip 6 months to 1 year. A slip in IOC date

would increase costs by approximately $7s

mill ion per month, so that the anticipated increase in MX/MPS cost wouId be on the order

of $0.5 billion to $1,0 billion. Given a decision

to proceed with adequate funding on a year-toyear basis, OTA believes that the FOC date

could be achieved even with the IOC SIippage.

This belief is predicated on the fact that funding and procedural mechanisms are provided

so that long Ieadti me resources can be marshal led for use when required,

System Cost

OTA had an independent cost assessment

conducted of the Air Force baseline system.

The cost was estimated for all stages of the

system, from development and investment

through operation and support for 10 years of

deployment.

In determining system cost, it should be

understood that the baseIine configuration for

MPS is not yet firmly fixed, as certain technological tradeoffs are still being considered

by the Air Force. The Air Force is in the process

of updating costs, but until the baseline configuration is finalized, new estimates are considered internal Air Force data and were not

made available for OTA’S analysis. In lieu of

this data, the Air Force provided detailed briefings covering methods used to estimate costs

and provided substantial backup material to

support their previous estimate of $33.8 biIIion

(fiscal year 1978 dollars) In addition, the draft

environmental impact statement (DE IS), particularly its technical appendices, contains additional information useful for estimating

costs. Also, some of the design changes

adopted as a result of the late-l 980 design

review have been incorporated into the estimate. Inputs drawn from the backup material

supplied by the Air Force have been used but

approp r iate adjustments have been made,

based on information contained in the DE IS

and other published sources. Therfore, a systems configuration has been selectected as a

basis for cost analysis that is compatible with

Air Force plans but which is SIightly different in

detail from the configurate ion used for the previous Air Force estimate

There is some contusion about the Air Force

baseline estimate A cost of $33.8 billion is

often quoted This dllar figure refers to the

baseline estimate, in constant 1978 dollars,

and incIudes 1 ()-year O&S (operation and support) costs for a tot alI lifecycle cost This figure

when escaIated to 1980 dolIars is $399 biIIion

Iifecycle cost, with a total acquisition cost of

$338 bilIion (This estimate also excludes the

cost of i m pactmitigation ) The Air force's

baseline estimate for the 4,600” shelter system

if shown in table 12

Table 12.—Air Force Baseline Estimate 4,600

Shelters (June 1978) (billions of dollars)

FY78$ FY80$

Development (RDT&E) . . . . . . . . $ 6.7 $ 7.9

Investment

Aircraft procurement . . . . . . . $ 0.3 $ 0.3

Missile procurement . . . . . . . 12.6 14.9

Military construction . . . . . . . 9.0 10.7

Total investment ., . . . . . . . $21.9 $25.9

Total acquisition. . . . . . . . . $28.6 $33.8

0 & s costs . . . . . . . . . . . . . . . $ 5,3 $ 6,1

Llfecycle costs . . . . . . . . . . $33.8 $39.9

SOURCE U S Air Force

Because of the controversy over these estimates, it is important to understand the conditions under which they were developed, and

their degree of accuracy. The MX Program has

cons idered a wide variety of basing modes, including silos, trenches, and air mobile in add ition to the present horizontal plan. For each

basing mode, several configurations were

studied and costed, an important consideration for each mode. In order to have a quickresponse estimating capability with a reasonable degree of accuracy, a cost model was developed by the Air Force. This model was

parametric, in which cost factors were developed for specific characteristics (or parameters) that describe a particular function, and
Ch. 2—Multiple Protective Shelters . 85

estimating. While it is not too difficult to estimate the construction cost of a given structure, the estimating process becomes very

complex under the conditions that exist for

MPS. First, the workers must be recruited outside the deployment area since the skills and

numbers required probably do not exist locally. Because of this situation, temporary construction camps must be established and housing, food, recreation, and heaIth care must be

provided for the workers. Everything from construction materials to loaves of bread must be

brought into the area over what is, at best, a

limited transportation network. In addition,

the technical facilities must meet exacting

standards to ensure survivability, postat tack

launch capability, and to protect PLU Thus, in

addition to construction workers, there must

be managers and inspectors to ensure quality

control, personnel to prepare food, truck

drivers to provide transportation, clerks to receive and store materials, and a number of

other supporting personnel, Solid and liquid

waste must be disposed of i n an environmentalIy acceptable manner.

Other are as where precise cost estimates

difficult include:

MX missile. ‘The decision for full -scale product ion is scheduled to be made long

before the flight test program is comp I eted and before the missile/cannister

combination has been tested. Such a pro- -

gram is feasible, but risks complication s

late in the test program causing design

changes, deIays, and production cos t

creases over those estimated.

Missile Decoy. This system, vitsl to the

v iability of MPS is not yet fully designed

Projected development and procurement

cost are highly uncertain at this time.

Missile Transporter. This transporter will be

the largest truck-like vehicle ever constructed and it includes highly sophisticated automatic controls, communications, and decoy systems.

Command, Control, and Communications

(C). Not all portions of this subsystem

have been specified at this time,
86 ● MX Missile Basing

● Electromagnetic Pulse (EMP) Hardening. It

does not appear that sufficient attention

to quality control was reflected in the

original Air Force estimate. Welds on the

steel Iiners installed in the Safeguard ABM

system for EMP purposes were found to

be a problem requiring special inspection

procedures, The MPS documents do not

discuss the welds required on the steel

Iiner installed in each shelter.

With the exception of construction issues

and the missile decoy, these uncertainties are

normal for advanced and complex weapons

systems at this stage of development. If the

earlier Air Force estimate of $33.8 billion has

not properly assessed the support required to

accomplish the construction program, the estimate could be substantially low. An error in

estimating the cost of individual protective

shelters is greatly magnified because a minimum of 4,600 shelters is required. Similarly, inadequate consideration of resources required

to support the construction effort will be magnified because of the remoteness of the proposed deployment area.

Notwithstanding these uncertainties, a comparison of the Air Force baseline estimate to

OTA’S estimate has been made (see table 13).

OTA estimates the total acquisition cost for

the Air Force baseline, with 4,600 shelters, is

$37.2 billion (fiscal year 1980 dollars), and a

total Iifecycle cost of $43.5 billion. As previously mentioned, the OTA estimate is $3.5

billion greater than the 1980 baseline estimate

developed by the Air Force. This differential

includes:

●

●

●

●

●

$06 billion in schedule contingency for

missile RDT&E,

$0.7 billion for engineering changes in system components,

$0.6 billion in construction costs primarily

associated with increased life support

costs,

$0.7 billion in A&CO costs reflecting

military pay for the Air Force personnel involved in this activity,

$0.9 billion in other adjustments.

As indicated in table 13, the Air Force has

not budgeted costs for the MX program for

program management and its Site Activation

Task Force,

Cost and Schedule of Expanding

the MX/MPS

As noted above, the proposed 4,600-shelter

system represents a baseline scenario. HowTable 13.—Comparison of Air Force and OTA Cost

Estimates (billions of fiscal year 1980 dollars)

USAF OTA

baseline baseline

estimate estimate

Develpment

Missile related . . . . . . . . . . . . .

Base related . . . . . . . . . . . . . . .

Other. . . . . . . . . . . . . . . . . . . . .

Investment

Nonrecurring production . . . .

Equipment procurement

Missile system . . . . . . . . . . .

Transporter/vehicles . . . . . .

Decoy . . . . . . . . . . . . . . . . . .

C

3 . 

. . . . . . . . . . . ., . . . . . . . .

Ground power. . . . . . . . . . . .

Physical security . . . . . . . . .

Support equipment . . . . . . .

Aircraft procurement. . . . . .

Total equipment & spares

Engineering change order. . . .

Facilities construction . . . . . .

Assembly and checkout . . . . .

Program management. . . . . . .

Site activation task force . . . .

Operating and support

Replenishment spares . . . . . .

System modifications . . . . . . .

Depot maintenance . . . . . . . . .

Operations and maintenance.

Military personnel . . . . . . . . . .

Civilian personnel . . . . . . . . . .

Training. . . . . . . . . . . . . . . . . . .

Other . . . . . . . . . . . . . . . . . . . . .

Total Iifecycle cost ., . . . . . . . . .

$ 5.025

2.839

.710

$8.574

$ 1.110

4.990

1.634

2.321

0.915

0.542

0.335

1.692

0.350

$12.779

$ –

10.035

1.318

$25.242

$ 0.647

0.187

0.227

1.480

2.077

0.410

0.192

0.910

$6.130

$39.946

$ 5.025

2.837

1.310

$9.172

$ 1.110

5.226

1.634

2.321

0.915

0.756

0.335

1.692

0.439

$13.320

$0.666

10.649

1.995

0.222

0.037

$27.999

$0.647

0.234

0.227

1.611

2.077

0.410

0.192

0.910

$6.308

$43.479

SOURCE Office of Technology Assessment
Ch. 2—Mu/tip/e Protective Shelters 87

● presently planned clusters are not backfilled in order to enhance survivability.

It seems possible to achieve the first goal,

8,250 shelters in operation by 1990, provided

there are no serious missile or site development problems, and that a decision to proceed

is made in the near future. A shelter completion rate of approximately 2,000 per year

would be required, This rate represents about a

two-thirds increase in the presently planned

construction rate (approximately 1,200 per

year). As in the baseline case of 4,600 shelters,

however, schedule slippage is likely. An expanded program schedule would also be in

jeopardy unless funding and authority mechanisms are provided so that the required resources can be programed and marshaled for

use when required.

While OTA does not have the information

available to detail alI resource requirements

for the expanded program, no resource constraints (construction materials, equipment, or

skilled personnel) are anticipated provided

that sufficient leadtime is availble between

the decision to undertake the program and

peak construct ion periods The Nevada Power

Co., for example, cannot presently meet peak

demands for electric power and has existing

purchase agreements with outside utilities.

Long-term agreements with the company

wouId be required if commercial power is to

be used to support the construction and operations phases of the MPS program as planned.

other such commitments would be needed

Table 14.—Land Use Requirements

Acres Acres Acres

Shelters . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11,040 (17) 19,872 (31) 29,808 (46)

Roads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74,824 (1 17) 134,683 (210)b202,024 (315)’

Operating

Bases and support . . . . . . . . . . . . . . . . . 51,456 (80) 92,620 (144) 138,931 (217)

Direct lands . . . . . . . . . . . . . . . . . . . . . . . . 137,320 (214) 246.176 (386) 369,264 (576)

Potential impact zoneb . . . . . . . . . . . 2,560,000 (4,000) 4,608,000 (7,200) 12,521,738 (19,565)

Numbers of shelters . . . . . . . . . . . . . . . 4,600 8,250 12,500

aDoes not assume backfill

—

bThis figure is based on the 0.25 mile disturbance zone discussed on page 70 and represents both the potential arid lands lmpact zone and an approxlfnatlon of the land

area which might be subject to restricted use under an expanded PLU security program

SOURCE Off Ice of Technology Assessment
Number of shelters

4

-

,600 8,2<0 12,500

Development

Mi:;sile .. . . .

Basin g

Other. . . . . . . . . . . . . .

l-otal . . . . . . .

Investment

Missile . . . . . . . . . . . . .

Cannisterllaunche r

Transporter .

Const ructioniactlvat ion

Other. .

l-otal ... .

Operating and suppor t

costs

Anlual ... . . . . . . .

Lifecycle costs

To FOC . .

To the year 2000. . . . . . .

To the year 2005, . . .

Operating personnel

Military personnel .

Civilian personnel . .

l-otal . . . . . . . . .

$ 5.0 $ 5.0 $5.0

2.9 3.0 3.1

1.3 1.4 1.5

$ 9.2 $ 9.4 $9. 6

$ 4.3 $ 6.1 $8.1

0.9 1.5 2.2

1.4 2.4 3.6

12.6 19.9 28.5

8.8 13.7 19,1

$28.0 $43.6 $61,5

$ 0.469 $ 0.719 $ 0,969

$38.6 $55.2 $77.7

$43.5 $62.4 $82.6

$45.7 $66.0 $87.4

10,900 16,450 22,000

1,700 2,600 3,500

12,600 19,050 25,500 —

SOURCE Off Ice of Technology Assessment

SOURCE Off Ice of Technology Assessment
Ch. 2—Multiple Protective Shelters ● 89

This method provides reasonable cost estimates for comparative purposes. Time and

information available for the estimate did not,

however, allow for a full investigation of the

impact of the increased requirements for

scarce resources (some missile materials and

propellants) or the potential impacts of economics or diseconomies of scale on the construction program. Final estimates, therefore

contain a significant degree of uncertainty and

further analysis is required before actual funding levels can be determined with precision.

Split Basing

The proposed MX/MPS basing plan calls for

the location of all shelters and support faciIities over a broad geographic area. Deployment clusters would be located in valleys

of the Great Basin and would be separated by

the mountain ranges which separate the

valIeys; but the system would otherwise be

operationaIIy contiguous.

The “split basing” option would be similar in

all functional respects except for the fact that

a large area of nondeployment land would separate the operational deployment areas. In

both cases the same number of missiles,

shelters, and land area would be involved, and

in both cases there would be two operating

bases. Figure 44 shows the geographic distribution of the proposed Air Force split basing

alternative.

From an operational standpoint, there are

no significant differences between contiguous

basing and split basing, Both alternatives reFigure 44.— Proposed Split Basing

Deployment Areas

- 1 ’

\

\

———

-- ——— /

.— — —— — ——,— — —— — — -

Legend

_ Suitable areas

u Unsuitable areas

0 Candidate sltlng

regions

—— State boundary

SOURCE A F IDEIS

quire the same number of missiles, shelters,

and operating bases; and both have the same

functional requirements for command, control, communications, security, and support.

From the standpoint of the costs of construction and the environmental impacts, however, there are several notable differences,

First, construction of split basing would cost

approximately 10 percent more than the baseline, as there would be some necessary duplication in geotechnical investigations, in

electronic and mechanical systems, in transportation and logistics, and some additional

costs in land acquisition resulting from the

need to negotiate easements or title for a

larger percentage of private lands. (See table

1 7.)

Second, impacts on both the physical environment and the regional economy could be

substantially different. Although the general

nature of the impacts would be fundamentally

the same as those resulting from the proposed

basing option, specific impacts could differ

83-4-7 - 1 -
90 ● MX M\ssile Basing

Table 17.—Air Force Estimates of Additional Split

Basing Costs (in millions of fiscal year 1980 dollars)

RDT&E . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Geotechnical . . . . . . . . . . . . . . . . . . .

Electronics . . . . . . . . . . . . . . . . . . . . .

Mechanical , . . . . . . . . . . . . . . . . . . .

Deployment . . . . . . . . . . . . . . . . . . . .

Procurement . . . . . . . . . . . . . . . . . . . . .

Airborne lunch control . . . . . . . . . . .

Helicopters . . . . . . . . . . . . . . . . . . . .

Initial spares . . . . . . . . . . . . . . . . . . .

Mechanical . . . . . . . . . . . . . . . . . . . .

Electronics . . . . . . . . . . . . . . . . . . . . .

Logistics . . . . . . . . . . . . . . . . . . . . . . .

Initial spares . . . . . . . . . . . . . . . . . . .

Deployment . . . . . . . . . . . . . . . . . . . .

(A&CO and training)

Milton . . . . . . . . . . . . . . . . . . . . . . . . . . .

Real estate . . . . . . . . . . . . . . . . . . . . .

Road network.. . . . . . . . . . . . . . . . . .

Remote surveillance . . . . . . . . . . . . .

Construction O&S . . . . . . . . . . . . . .

Training facilities . . . . . . . . . . . . . . .

Design funds . . . . . . . . . . . . . . . . . . .

Designated assembly area and

contractor support area. . . .

Total . . . . . . . . . . . . . . . . . . . . . . . . . . .

$ 63

27

16

5

. . . . . .

59

29

10

28

157

63

$1,761

. . . . . .

$ 527

53

11

32

54

41

465

. . . . . .

$ 121

2,171

$1,183

$3,475

SOURCE US Air Force

significantly based on the site-specific characteristics of the impact regions.

In general split basing would mitigate the

impacts on the physical environment by dispersing the direct impacts, and could have the

effect of avoiding impacts on certain areas

altogether, or avoiding critical thresholds in

particular instances. In regard to socioeconomic impacts, split basing would complicate the issues of land-acquisition and integrated planning, but offers the possibility

that impact levels would be within the management capabilities of more communities,

and thus result in more beneficial impacts and

fewer boomtown conditions.

In the case of socioeconomic impacts there

may be a third qualitatively different type of

impact associated with split basing. In addition to the reduction of adverse impacts noted,

and cases in which the reduction in impacts effectively eliminates the adverse impacts (e.g.,

a case in which the reduced growth level resulted not only in a reduction of the level of

overcrowding in schools, but reduction to a

level that presented no over-crowding), split

basing could transform negative impacts into

positive impacts in instances where the level of

new growth was with in the carrying capacity of

the existing social infrastructure.

Thus, not only would the level of negative

impacts be reduced, but in many smalI communities, and most Iikely in the larger towns

close to the operating base areas, negative impacts could become positive impacts,

Physical Impacts

Based on the Air Force resource analysis

relevant to the split basing option, it is apparent that split basing would have significantIy less impact on wildlife and the physical environment than the baseline option. * (See fig.

45,’)

There are, however, other complicating factors regarding the proposed split basing option. In the Great Basin of Nevada and Utah,

virtually al I of the land is owned by the Federal

Government, and the dominant economic activities (ranching and mining) are subject to

lease and permit authorities. In the split basing

deployment area of New Mexico and west

Texas, 95 percent of the land is in private

ownership and is used primarily for crop

production and livestock. The differences between use of rangeland and cropland, and the

differences between private and public ownership of the land, raise potentialIy significant

questions. First, as noted above, the use of

croplands would take a greater amount of agricuItural land directly out of production; but,

the higher productive capacity of the land

would also facilitate restoration of the impacted areas. AS a result, considerably less

land would be likely to be lost from productivity.

‘See D[ 15 ma(rll, and J(I p 1-1, includfng vegetation, habitat,

and protect ed and endangered spec Ies Add It IorlalI y, theAlr

Eorce has Indicated that impacts on the c haracterl~tlcs of the

prl~tlne environment, archaeological and historical sites, local

pc,pulations, and econornlc adjustment, would also be reduced

urlder the SPI It basing opt Ion
Ch. 2—Multiple Protective Shelters ● 91

Figure 45.—Summary Comparison of LongTerm Impact Significance Between

the Proposed Action and Split Basinga b

Natural environment resources I

Proposed DDA (Nevada/Utah]

action 1 –OB (Coyote Spring Clark Co )

(PA)

2– OB (Milford/Beaver Co

DDA (Nevada Utah)

Split basing DDA (Texas New Mexico)

1— OB {Coyote Spring Clark Co

2—OB (ClOVIS Curry Co )

Human environment resources I

Act Ion

Proposed DDA ( Nevada, Utah)

actio n 1 – 06 (Coyote Spring Clark Co

(PA) 2 OB (Milford Beaver Co )

DDA Nevada/Utahl

Spilt. DDA [Texas New Mexico]

basing 1 OB (Coyote Spring Clark Co

2 – OB (Clovis Curry Co )

No significant impact Low significance Moderate significance[gmflcance High significant impact

aWhile there may be an overall estimate of no impact or low impact when considering the DDA region as a whole it must be recognized that during short term Construe.

tion activities specific areas or communities within or near the DDA could be significantly Impacted

b

The reduction in DDA size for Nevada\Utah under split basing does not neceddstily change the significance of impact on a specific resource Many Impacts occur in a

Iimited geographic area which IS Included in both the full and spilt deployment DDAs, or are specific to the OB suitability zone

SOURCE U S Air Force/DEIS

Second, the legal basis for conducting necessary PLU activities is more clearly defined in

relation to privately owned lands than it is in

relation to public lands. In the case of private

lands, it would be necessary to negotiate

easements to allow for access to shelters and

for periodic “security sweeps” and investigations; but the contractual basis for such

arrangements are unambiguous In the case of

the public lands the necessity of periodic

sweeps raises legal questions regarding possible restrictions on public use or access to

public lands.

Finally, in terms of land acquisition, it is

uncertain whether the political process of land

withdrawals necessary for use of the public

lands might be more or less cumbersome than

the process of individual negotiations with

private landholders. It does appear likely,

however, that the process of acquiring lands

through both the congressional land withdrawal process and private negotiations,

would be more cumbersome than reliance on

Federal lands alone.
92 MX Missile Basing

VERTICAL SHELTERS

An alternative to employing horizontal

shelters for MPS is to house the missiles in

more conventional vertical shelters. (See fig.

46. ) Aside from the difference between

whether the missile is stored horizontally and

erected to vertical for launch, or stored vertically in a ready launch position, there are

Figure 46.—Vertical Shelter

MobiIe operati

support equip

 Fixed foa m

— Missile capsu

Batteries and

— egress actuat

SOURCE: U.S. Air Force

onal

ment

Ie

or

several important issues. One issue, and

perhaps the primary one, is shelter hardness.

Pound for pound of concrete, vertical shelters

are more resistant (harder) to the effects of

nearby nuclear detonations. Shelter response

is easier to analyze and we have more experience in testing and building vertical

shelters. A second important issue is the ease

and speed of missile movement, particularly

the insertion and removal times of the missile

at the shelter. A horizontal shelter allows a

simple roll transfer of the cargo between the

transporter and the shelter; transfer for a vertical shelter requires the additional transporter

operation of erecting the missile to vertical for

insertion and removal from the shelter. A third

issue, arms control monitoring, is discussed

below.

Shelter Hardness

There are several damage mechanisms to a

missile from a nuclear detonation. These

mechanisms are airblast, ground shock,

electromagnetic pulse, radiation, and thermal

effects. Airblast resuIts from the intense compression of air at the explosion, that propagates away from the source as a supersonic

shock wave. An airblast results in overpressure

destruction, and it is particularly severe on

aboveground objects (such as the shelter door

of a horizontal shelter) that must withstand the

reflected loads of the incident shock front. For

a vertical shelter, with a shelter door that is

flush with the surface, there are no reflected

Ioads, and door requirements are far less

severe than for the horizontal shelter. In addition, ovalling of the horizontal tube is a more

serious problem than is the compression on the

vertical shelter.

The task of testing and modeling for dynamic (wind) pressure is also more difficuIt for

horizontal than for vertical shelters. Because

the dynamic flowfield for the horizontal case

is sufficiently complex, adequate simulations

are difficult. The result is a less complete capability to test and validate a horizontal

shelter design. Nevertheless, it is believed that
Ch. 2—Multiple Protective Shelters ● 9 3

with a sufficiently comprehensive validation

program, confidence in horizontal shelter

hardness can be adequately established.

Ground motions result from the “air-slap” of

the shock front hitting the ground as well as

propagation through the earth of upstream

coupled energy. The damage mechanism of

dominant concern is the missile coming up

against and forcibly hitting the shelter wall

from the inside, as the shelter moves with the

ground, To design for this in a simple MPS

shelter, the missile is given enough space inside the shelter to move before coming up

against the shelter wall. This space between

missile and shelter is called rattle space, and

for shelters several thousand feet distant from

a 1-MT nuclear detonation, typical rattle space

is tens of inches. Since at ranges of interest

ground shock motions are typically larger in

the vertical than horizontal direction, vertical

shelters require less concrete than do horizontal shelters, since the inside diameter of the

shelter does not need to be as large. In addition, the missile is constructed to be more

resiIient to motions along its length than transverse to it.

For radiation and thermal effects, since the

flux direction on the surface is along the

ground, more stringent requirements for the

horizontal shelter door are necessary than for

the surface-flush vertical door. Electromagnetic pulse effects do not appear to discriminate strongly between horizontal and vertical shelters, although the greater radiation attenuation afforded by the vertical shelter

would ease hardness requirements for radiation-induced electromagnetic puIse,

In summary, it appears that building a survivable horizontal shelter is a more demanding

task than would be the vertical shelter, and

vertical shelters can be easily made more than

1,000 psi hard, whereas the design and hardness validation of a 600 psi horizontal shelter

pushes state of the art engineering, Nevertheless, for an MPS system, this hardness should

be enough. MPS does not rely on the shelter

surviving a direct attack, but by surviving the

effects of an attack on neighboring shelters, To

the extent that a fractionated threat would

reduce warhead yield, consideration might be

given to building a sufficiently hard vertical

MPS, perhaps several thousand psi hard, in

order to withstand the increased threat

without building more shelters. Nevertheless,

because shelter kill probabilities are exceedingly sensitive to missile accuracy, and

Soviet missile accuracies are projected to continue to improve, hard vertical shelters still

would not be likely to survive a direct attack.

Therefore, shelter number requirements for

vertical shelters might not be significantly different from horizontal shelters. (This question

is more thoroughly addressed in the classified

annex. )

Even though vertical shelters will be harder,

the state of knowledge of electromagnetic

pulse effects is not considered firm enough to

allow shelter spacing for any shelter design

much less thay 5,000 ft, which is the current

spacing for baseline horizontal shelter MPS.

However, there exists the possibility that vertical shelters could be more densely “packed”

in the same area (e. g., by backfilling) and

would therefore require less land for the same

number of shelters.

Missile Mobility

For the Air Force baseline, it is stated that as

a hedge against a loss of PLU, the missiles

would have the capability of rapid relocation

and an on-road hide-on-warning capability

against SLBM attack. This reliance on missile

mobility makes missile transfer timelines important to the choice between horizontal and

vertical shelters. The relevant difference here

is the time required for insertion and removal

of the missile. Because the transporter for the

vertical system must perform missiIe raising

and lowering operations with a strongback,

rather than the roll-transfer operation for the

horizontal system, the transporters for the two

systems are designed differently. (See fig. 4 7

for the transporter designs that have been

studied. ) Although a horizontal shelter transporter has not yet been constructed to test

timelines, an operational vertical shelter

emplacer has been constructed and tested at

the Nevada Test Site (NT S). Remove and install
94 ● MX Missile Basing

Figure 47.—Transporter for Vertical Shelter

Canister

emplacement

hoist

I

0 0 0

Concrete

shelter wall

I

--------- 7 - >

---------- 

J —

Shelter

door

Emplacement of

missile canister

in vertical shelter

SOURCE U S Air Force

timelines for horizontal and vertical systems

based on these transporter designs and on the

NTS field tests as shown in figure 48, The vertical system timelines are based on extrapolation of test data, such as increased automation, adding more hydraulic pumps for the

strongback Iift actuator, and so forth in order

to optimize transfer time. Horizontal system

timelines are based on the current baseline

design. Using these two transporter designs

and the test figures, emplacement and removal

times are slightly under 5 minutes for the horizontal system, and somewhat over 22 minutes

for the vertical system can be seen, It must be

emphasized that these figures are based on

given transporter designs; different timelines

may be derived based on unfamiIiar designs.

Also, the figure for vertical emplacement is

based only on design mechanical constraints.

No consideration has been given to further

constraints that may be imposed by explosives

handling,

Based on these figures, relocation time for

the vertical system is longer than for the

horizontal system, due only to the transfer

times. When adding travel times, relocation

for the horizontal system is about 9 hours, and

for the vertical system, 15 hours.

For hide-on-warning dash from the road, emplacement figures for the baseline horizontal

are presented in figure 49 but none was available for the vertical. Because of the very tight

timeline for the dash missile emplacement operation, it would necessarily take a very different vertical system transporter to satisfy the

2-minute insertion schedule needed to support

an SLBM-timeline dash. Among the current

conventional designs, only the horizontal system could support the SLBM dash.

PLU

Because most of our detailed understanding

of PLU has come only in the last several years,

when the baseline system has been horizontal,

it is difficult to say with confidence if PLU provides an adequate basis for preferring a

horizontal or vertical shelter. We do not know

as much about the signatures and countermeasures for the vertical system to make a reliable comparison. It is almost certain, however, that many of the countermeasures designed for the horizontal system wiII need to

be modified or completely replaced for a vertical system. The mass simulator will probably

be quite different. (An early design for a vertical simuIator, called the “chimes,” because it

was composed of four vertical rods, may not

be feasible because its vibrational modes are

simiIar to the discarded T E L simuIator concept; see pp. 97). Much PLU design work would

have to be done to resolve these questions.

costs

OTA estimated the cost of deploying the MX

missile in vertical shelters in the Great Basin

region of Nevada and Utah. The estimate

assumes that, with the exception of shelter and

transporter costs, the costs associated with vertical shelters are the same as the costs associated with horizontal shelters, Thus, the costs

of the missile, C3

, physical security, ground

power, environmental control, support faCilities, roads, and other support elements are

considered to be independent of shelter design

at least in total. Other ground rules include:
Ch. 2—Multiple Protective Shelters ● 95

Figure 48.— Remove/lnstall Timelines for Horizontal and for Vertical Shelters

● Comparison — horizontal/vertica l systems

— Co-locatable mass simulator

on site time

— Horizontal

. Potential timeline increase due to PLU (O = 8 rein)

Position 1.08

transporter 

2.88

Remove

3.25

Install

Position road 4.43

for travel

4.95

Retract shield ❑

— Vertical

- Superficial PLU analysis performed

Alignment

and

stabilization =

Closure removal and

raise strong back -

12.4

Install

Remove

Install closure and

lower strong back

Secure site

SOURCE U S Air Force

●

●

●

●

●

4,600 shelters;

200 deployed missiles, one per cluster of

23 shelters;

shelter spacing of about 5,000 ft;

approximately 8,000 miIes of roads; and

IOC and FOC dates identical to MX/MPS

in horizontal shelters.

The total construction costs of 4,600 vertical

and horizontal shelters are $5.1 billion and

$6.3 billion respectively (in fiscal year 1980

dollars), a difference of $1.2 billion. These

costs were derived from the application of the

Air Force DISPYIC model and cost inputs applicable to the horizontal shelter program

(materials costs). Horizontal shelter costs were

taken from material furnished by the Air Force.

20.5

22.5

The major differences between horizontal and

vertical shelter costs result from different

material requirements and construction costs.

The following characteristics of the two types

of shelters illustrate the reasons for the differences:

Horizontal

Length 171 ft

Inside diameter 145 ft

Wall thickness 21.0 inches

Concrete . 934 yd

Rebarsteel 35 tons

Liner steel 62 tons

Miscellaneous steel 21 tons

VerticaI

122 ft (deep)

131 ft

101 inches

254 yd ‘

15 tons

16 tons

4 tons

Thus, 4,600 horizontal shelters would require about 3. I million cubic yards more con-
96 ● MX Missile Basing

Figure 49.— Dash Timeline for Horizontal Shelter

Time (seconds)

Task 100 200 300 350

0

I

I

Command initiation 2 I

I

I

Travel time 231 . , 233 I

I

I

I

I

Open closure and position 37 196 233

transporter for transfer I

I

I

2 4 5

I

Prepare for transfer 12 I

I

I# ;

Remove simulator 28 273 ;

I8 :

,

Emplace launcher 46 319 i

I I

Remove transporter 5

b

I

I

Secure protective shelter 23 328 i 350

I

I

I

SOURCE U S ir Force

rete than vertical shelters and about 380,000

tons more steel.

The transporter required for the vertical

mode could be smaller than for the horizontal

shelter (according to previous Air Force designs). This difference would result in a reduction in cost of about $250 million to $500

m i I I ion for the 200 transporters required.

The horizontal shelter program is estimated

to cost about $43.5 billion to the year 2000.

This estimate includes $9.2 billion in development, $28 billion for investment, and $6.3 billion for operating and support costs. A vertical

shelter program would be about $1.5 billion

less expensive, or a total of about $42 billion

for the Iifecycle covering the deployment

years (IOC to FOC) and 10 years of full-scale

operations. Table 18 shows a breakdown of

horizontal and vertical shelter Iifecycle costs.

Arms Control

There are few differences, in principal, between verifying an arms control agreement for

a Vertical or horizontal MPS deployment, if the

basing mode has been designed with arms control agreement verification measures. The key

arms control agreement verification tasks

associated with the basing mode include counting the number of missiles deployed and

monitoring vertical shelter construct ion to ensure that the shelters are not actually new

ICBM launchers.

So long as, at a minimum, the MX missile

and its associated equipment are assembled in

the open and left exposed for a period of days

to permit accurate counting, the number of

missiles and associated vehicles could be adequately verified. Deployment of the missiles

and associated vehicles along a dedicated
Ch. 2—Multiple Protective Shelters ● 9 7

Table 18.— Lifecycle Costs for Horizontal

and Vertical Shelters Deployed in Nevada-Utah

(billions of fiscal year 1980 dollars)

Horizontal Vertical

Number of missiles deployed

Number of shelters . . . . . . . . . .

costs

Development

Missile ., . . . . . . . . .

Basing . . . . . . . . . . . . .

Other. . . . . . . . . . . . . . .

Total . . . . . . . . . . . . . .

Investment

Missile/cannister/launcher

Transport/vehicles ... .

c’. ... . . . . . .

Other equipment . . . . . . . . .

Construction . . . . . . . . . . . . .

A&CO . . . . . . . . . . . . . . .

Other. . . . . . . . . . . . . . . .

Total investment

Operating and support

Procurement . . ... . .

O&M . . ... . . . . . . .

Personnel. . . . . . . . . .

Trainin g

Other. ... . . ... . . . . .

Total O&S

Lifecycle costs .

200

4,600

$ 5.0

2.9

1.3

$ 9.2

$ 5.2

1.6

0,9

5,5

10.6

2.0

2.2

$ 28,0

$ 0.9

1.8

2.5

0.2

0.9

$ 6.3

$ 43.5

200

4,600

$ 5.0

2.9

1.3

$ 9.2

$ 5.2

1.3

0.9

5.5

9.4

2.0

2.2

$ 26.5

$ 0.9

1.8

2.5

0.2

0.9—

$ 6.3

$ 42.0

transportation network to the deployment area

would also permit counting of the missiles.

These assembly and transportation procedures

are common to the horizontal and vertical

shelter deployments, indicating that these

arms control monitoring aspects would appear

to be the same.

However, the horizontal basing mode appears to some analysts to be a more desirable

basing mode because it facilitates confirmation through direct observation that those

missile shelters said to be empty of missiles do

not in fact contain missiles. The Air Force

baseline system relies on removable plugs in

the shelters to permit such direct observation.

The incremental value of such observation to

arms control agreement verification is controversial.

SOURCE Off Ice of Technology Assessment

SOME PREVIOUS MX/MPS BASING MODES

The Roadable TransporterErector- Launcher (TEL)

In the period between the start of full-scale

engineering development in September 1979,

through the spring of 1980, the missile and

launcher were designed to be structurally integrated with the transporter, into a roadable

vehicle called the T E L, for transporter-erectorlauncher. (See fig. 50. ) The entire TEL unit was

to be placed in the protective shelter. On command to launch, the shelter door would open,

the TEL would plow through any debris, erect

the missile to a near vertical position, and

launch the missile,

The TEL could exercise several mobility options. One mode, used for maintenance and

rapid relocation, would have the TEL transported, and shielded under a towed, wheeled

vehicle called the mobile surveiIlance shield.

The surveillance shield would visit every

shelter, simulating a TEL insertion at each one

except for the shelter where it actually deposits the TEL. This operation would be

manned. Travel to all shelters was estimated to

be about 12 hours, as in the current design.

A second mobiIity mode would permit a portion of the force to be on the road, under the

surveillance shield. This manned hide-onwarning operation would respond to SLBM attack warning, and secure the TEL at the nearest

shelter before the attacking warheads arrived.

Like the first mode, this is similar to the

presently designed capability,

The third mode of missile mobility was

called the dash. Dash was to be an unmanned

operation. Upon receipt of warning of an

ICBM attack, the TEL would leave its shelter,

unconcealed, and dash to another shelter
98 ● MX Mlsslle Basing

Figure 50.–Roadable Transporter- Erector.Launcher (TEL)

SOURCE U S Air Force

within the cluster. To be successful, this would

have to be done within the 30-minute flight

time of attacking ICBMS. Arranging th e

shelters in a closed loop would facilitat e

dashing into any other shelter in the cluster,

This closed shelter arrangement with the dash

operation led to the colloquial term, “MX

Racetrack. ” This last mobile option could not

be retained in the present “loading dock”

design.

The most serious shortcoming of the TEL design is the difficulty of maintaining PLU, according to Air Force analysis. The TEL shelter is

larger than the present shelter design by 2 ft in

diameter, and in order to have the possibility

of satisfying PLU, the shelter needed to be

even further expanded to be able to house a

credible TEL simulator and still support the

dash capability. With the 16.5-ft inner

diameter shelter of the TEL design as a constraint, al I decoys studied by the Air Force had

a poor signature match to the TEL. One design

used two rods inserted between the inner and

outer diameters of the shelter to act as a

InissiIe simuIator. However, it was learned that

the different vibration modes of the rods, as

welI as other d instinctive signatures, would be

evident during transit, simulator insertion, and

removal. These arguments are quantitatively

plausible.

Concerning the three mobility options discussed above, the first two are similar to the

loading dock arrangement. For the third mobility option, unmanned dash, transferring the

TEL during an ICBM flight time would leave it

exposed during its transit to a coordinated

SLBM attack, since the TEL unit is not designed to survive such an attack. Typical hardness for such a vehicle wouId be in the range of

5 to 10 psi, which lies approximately at the 1 to

2 mile contour for an exploding SLBM warhead. If, as suspected, PLU had been broken

and the enemy knew the shelter Iocation of the
Ch. 2—Multiple Protective Shelters ● 99

TEL, then it could be vulnerable to an SLBM attack during the dash operation.

Other than the transporter design, dash, the

larger shelter, and the closed cluster layout,

this MPS design is the same as the present

baseline system

The Trench

The trench was an even earlier design for

basing the MX missile, before MX entered fullscale engineering development In this mode,

the missiIe, housed on an unmanned transporter and launcher, would reside in an underground concrete tunnel, out of public view,

(see fig. 51), As in multiple shelters, trenchbasing the MX relied on keeping the missile

location in the trench unknown to the attacker. The missile could randomly move in

the trench as an additional PLU measure In

order to launch the missiIe, the transporter

would break through the roof and erect the

missile, preparatory to launching.

Several trenches have been designed for MX

basing. Some trenches were continuously

hardened, others were hardened in sections.

Some trenches had single spurs in which the

missile resided, and others had double spurs.

Most trenches were designed with inside ribs to

Figure 51 .—Trench Layout

Transporter/launcher breaking

through surface of trenchtrenrh

4,200 (1 ,280 m)

/

/ w -

.

.

-\ -/’ 13 ft (3.96 m)

Plug to protect against

nuclear blast in tunnel

SOURCE Off Ice of Technology Assessment
100 ● MX Missile Basing

accommodate blast plugs, designed to protect

the missile (see fig. 52).

An early concern for trench basing was the

possibility that the trench tube would serve as

a shock wave guide. Specifically, the fear was

that in an attack on the trench, the shock wave

propagating down the tube (largely unattenuated due to the trench’s one-dimensional

geometry) would result in conditions capable

of breaching the blast plug and destroying the

missile beyond a range where it presumably

would survive the internal airblast. Steps were

taken in trench design to protect the missile

from the in-trench shock wave propagation.

This design included stationing the missile in

tunnel spurs, so that the plug wouId experience

the side-on overpressure and not the direct

refIected shock.

A series of high-explosive blast tests on the

trench was performed at Luke-Yuma in 1977-

78 (HAVE HOST, T-series), to investigate the

above concepts for missile protection in the

trench. Results of the tests indeed validated

the blast plug concept on a half-scale trench

test, and vividly showed the reflected shock

venting at the plug. Even more significant,

analyses by the Defense Nuclear Agency

showed that even in the absence of blast plugs,

hot air ablation of the tunnel walls (as well as

other mechanisms) would attenuate the wave,

such that the pressure impulse transferred to

the plug would be approximately the same as

if the trench were not even present.

A far more serious problem for the trench

would have been PLU. Even though the missile

would not be visible, its motion on the transporter, 5 ft underground, would not be difficult to detect. A large number of signatures

would enable an observer to establish its location. (For a generaI discussion of these sigFigure 52. —MX Trench Concepts

Mine

hybrid

trench

Turning

structure

Launch

SOURCE U S Air Force
Ch. 2—Multiple Protective Shelters ● 101

natures, see the earlier section “Theory of Moreover, security along the entire trench

MPS. ”) Therefore, missiIe-transporter simu- Iength probably also would be necessary,

Iators would be necessary to install, at which which would make the system less acceptable

point system cost would be a deterring factor. to the deployment region.

MINUTEMAN MPS AND NORTHERN PLAINS BASING

One means proposed to protect the survivability of the Minuteman I I I component of

the present land-based missile force is to

redeploy these 550 missiles in an MPS system

similar to that proposed for the MX deployment in Utah and Nevada, For this case, vertical shelters would be constructed in the existing Minuteman base areas, The existing

Minuteman missiles would be modified so that

they could be moved more easily among existing silos and the new ones. Like the MX/MPS

basing mode, survivability would be sought by

constructing more shelters than the Soviets

had warheads available to target them. As a

weapon, the Minuteman I I I could be improved

to achieve MX design accuracy by backfitting

the MX guidance unit, Such a force could use

the existing Minuteman bases, public roads,

and support infrastructure.

Missile Modifications

A number of minor modifications would

need to be made to the present Minuteman

missile, To facilitate the increased handling of

the missile, it would be placed in a cannister.

Attachment tabs, or their equivalent, would be

instal led on the stages to accommodate cannisterization. The entire missile would be

transported, unlike the present Minuteman

missile, which moves the first three stages and

the fourth stage, separately, I n addition, several attachments in the missile that were

originalIy built to accommodate vertical orientation of the missile, might need strengthening

to support horizontal motion of the missile

during transport. The Minuteman guidance

unit would also need modification, None of

the modifications to the Minuteman missile

appears infeasible,

Most technical risks associated with an

MX/MPS deployment would also be a factor

for a Minuteman MPS deployment. Most

notably, PLU would be Iikely to be as formidable a task as for MX. Also, demands on

system expansion due to an increased Soviet

threat would be similar to the case with MX,

Since the Minuteman missiles, roads, and infrastructure are already available it might

seem possible that the cost and time needed to

proceed with such a deployment could be significantly less than for MX baseline. To examine this hypothesis, Minuteman deployments, corresponding to the baseline MX/MPS

deployment and for expanded threats were observed, and estimates were formed for cost

and schedule. The cases are the following:

●

●

Case 1, Baseline. Encapsulate existing 550

deployed Minuteman Ill missiles and 117

MM Ill currently in storage and modify for

MPS and cold launch. Modify the existing

550 silos to accept the encapsulated missile.

Build 5,250 new shelters, for a total deployment of 5,800 shelters, spaced a minimum of

l-mile apart. Deploy 5,250 decoys, and one

transport for every two missiles. Reopen the

MM I I I production line to replace missiles

taken from storage. This mix of missiles and

shelters would retain the same number of

surviving Mark 12A warheads after a Soviet

attack as the baseline MX/MPS system when

deployed in conjunction with a planned

Minuteman force of 350 MMIIIs and 450

MM IIS,

Case 2, Expanded 1990 Threat. Deploy a cost

optimum mix of Minuteman missiles and

shelters, determined to be approximately

900 missiles and 10,400 shelters.
102 ● MX Missle Basing

 Case 3, Expanded 1995 Threat. Deploy a cost

optimum mix of Minuteman missiIes and

shelters, determined to be approximately

1,1 ()() missiles and 15,500 shelters for this

threat level

Cost and Schedule

Cost estimates are given for these three

cases and the A i r Force baseline system i n

table 19.

I n case 1, it is estimated that 5,800 shelters

with 667 MM I I I missiles could be constructed

in the Northern Minuteman Wings for about $7

billion (fiscal year 80 dollars) less than the AF

baseline system.

In case 2, corresponding to a 1990 Soviet

threat level of 7,000 RV’S the cost estimate is

$534 billion for a system of 900 MMIII missiles

and 10,400 shelters.

In case 3, corresponding to a 1995 Soviet

threat level of 12,000 RV’S, the cost estimate is

$724 billion for a system of 1,100 MMIII

missiIes and 15,500 shelters.

The major cost drivers for these cases are

mechanical systems (transporters and decoys,

Table 19.—Minuteman MPS Costs

(billions of fiscal year 1980 dollars)

Missiles . .

Shelters . . . . . .

cost

R&D ... . . . . . .

Investment

Nonrecurring .

Missile . . . . . .

Equipment . . . .

Aircraft . . . . . .

Engineering

change orders

Constructio n

Assembly and

checkout. .

Other. . . . . . . .

Total

investmen t

O&S to year 2,000.

Lifecycle cost. .

Baseline

667

5,800

$ 2.5

1.4

2.7

9.7

0.5

0.6

10.4

2.4

0.3

28.0

5.9

36.4

Expanded Expanded

1990 Threat 1995 Threat

900 - 1,100

10,400 15,500

$ 2.5 $ 2,5

1.4 1.4

5.3 7.4

14.8 21,7

0.5 0.5

1,1 1.5

15.7 21.7

4.1 5.9

0.3 0.3

43.2 60.4

7.7 9.5

53. 4 72,4

primarily), construction, and assembly and

checkout in the investment phase, Operations

and maintenance and personnel costs drive the

operating and support phase. MMIII missile

R&D effort is minimal in relation to MX,

assuming a maximum dependence on the existing Minuteman road network and C network, There would still need to be a substantial upgrading of the existing roads and new

roads to the new shelters wouId be required.

If a decision to deploy Minuteman/MPS

were made in the summer of 1981 it is still

unlikely that IOC could be achieved before

1987.

Assuming a period of 18-30 months for site

selection and land acquisition (including E IS

preparation), it could be possible to start construction on new silos in late 1984 or early 1985

(see fig. 53) with a resultant IOC date of late

1986 or early 1987. At the same time other activities that would have to proceed in parallel

would include:

● development of a missile decoy and PLU,

● development of a transporter,

● cold launch development,

 definition of additional C requirements,

● upgrading of existing roads and construction of new roads to withstand the weight

and length of a new transporter.

Schedule for FOC depends, in part, on peak

construction rate. Assuming a peak construction rate of 2,000 shelters per year, by October

1986, FOC for Case 1 is projected to be 1989 or

Figure 53.— Minuteman/MPS Schedule

1 I

Go-head

decision i

 Ei S

I FSED

I

go-head

I I Land acq

I

i Facilities constr

I I A Shelter constr

CY 1$81 I 1932 I 1$83 I 1084 I 1985 I

SOURCE Office of Technology Assessment SOURCE Off Ice of Technology Assessment
Ch. 2—Multiple Protective Shelters 103

1990 Case 2 and Case 3 FOCs are projected by

1991 and 1994, respectively

An additional question which couId be significant, but which has not been anaIyzed, regards the cost associated with upgrading roads

to accommodate a deployment of MX missiIes

in the Northern Minuteman fields I n contrast

to the Minuteman transporter, which wouId

weigh approximately 2 15,()()() I b loaded, the

loaded MX transporter would weigh close to

1 6 milIion I b Modification and opgrading of

roads to accommodate this transporter C Ould 

affect cost, scheduIe, and socioeconomic impacts

CIVILIAN FATALITIES FROM A COUNTERFORCE MPS STRIKE

Interest has been expressed concerning the

level of civilian fatalities resulting from a

Soviet nuclear attack on an MPS-based MX deployment. Specifically, because the number of

nuclear detonations in such an attack would

run into the many thousands of megatons,

there is concern that civilian deaths resulting

from radiation fat lout would be so large that it

might be questionable if such a n attack couId

in any sense be considered a “ limited counterforce” strike.

I n order to approach this problem, OTA obtained a series of calculations on resultant

radiation doses over populated areas for a

number of cases involving a nuclear strike on

an MPS field. These computations are regarded only as representative and approximate at

best. It is customary for such calculations to

yield a wide range of results, and these are no

different, The reason for this range is that

resu Its are strongly sensitive to a number of

factors, including wind speed and direction,

wind shear, burst height of the weapon, and

the weapon’s fission fraction, It is not unusual

to see variations in calculated fatality levels of

at least an order of magnitude for differing

wind speeds. Furthermore, different computer

codes for the same physical circumstances

(winds, etc ) customarily yield results differing

by a factor of 2 or 3. We have not attempted to

resolve these differences, but have used a set

of runs using the Weapons System Evaluation

Group (WSEG) code as typical among different

codes. I n addition to these caveats, there are

some additional I imitations to these particular

calculations. First, these computations rely on

an urban-only population data base, consisting

of 140 miIIion people Therefore, total fatal i ties wiII be underestimated because fatalities in rural areas wilI not have been

counted. Second, because the number of

nucIear detonations wouId run into the many

thousands, significant total doses depend on

very small dose levels from the individual

weapons. Because data at these smalI doses is

scant, the value of any of these faIlout models

should be suspect

As an illustration of our population data

base, we show in figs. 54 A-D the population in

Figure 54A.— Population Subject to Fallout v.

Wind Direction

100

Mx in Nevada and Utah

90 — Range: 500 nm

80 —

70 —

60 —

50 —

40 —

30 —

“o 50 100 150 200 250 300 350

Wind direction (in degrees)

SOURCE Lawrence Livermore Laboratory
104 MX Missile Basing

Figure 54B.— Population Subject to Fallout v.

Wind Direction

100

Mx in Nevada and Utah

90 — Range: 1000 nm

70

60

n

-

. 50

t

20 —

10

0 50 100 150 200 250 300 350

Wind direction (in degrees)

SOURCE Lawrence Livermore Laboratory

Figure 54C.— Population Subject to Fallout v.

Wind Direction

MX in Nevada and Utah

90 Range: 1500 nm

80

70

60

50

40

30

20

10

0

0 50 100 150 200 250 300 350

Wind direction (in degrees)

SOURCE Lawrence Livermore Laboratory

Figure 54D.—Population Subject to Fallout v.

Wind Direction

100 MX in Nevada and Utah

90 — Range: 2000 nm

80 —

70 —

E

c 60 —

.= 50 —

Wind direction (in degrees)

SOURCE: Lawrence Livermore Laboratory

the path of radiation fallout versus wind direction, at distances from the MPS fields of 500,

1,000, 1,500, and 2,000 nautical miles. In these

charts, a wind direction of 00 is from north to

south. Similarly, a wind direction of 1800 is

from south to north. A wind direction of 2700

points due east. In fig. 54A, the peak at 250

represents the Los Angeles area, 800 corresponds to the San Francisco Bay area, and so

forth.

To determine the range of lethal fallout, and

therefore the magnitude of civilian radiation

fatalities, figure 55 shows the dose, in rads,

resulting from the detonation of a 1 -MT weapon with downwind distance. These doses are

plotted for a range of possible wind speeds,

from 20 knots to 60 knots. For example, with 20

knot winds, the one rad contour would extend

to about 800 nautical miles (for a single l-MT

weapon). This contour would extend to about

1,400 nautical miles (or 1,600 statute miles)

with 40 knot winds, and so forth. The 10- to 20-

km altitude is the region where the mushroom

cloud stabilizes and carries the bulk of the
Ch. 2—Multiple Protective Shelters ● 105

Figure 55.— Downwind Distance v. Total Dose

4

WSEG model as modified by Ruotanen

 =. “-.? .

4

024 6 8 10 12 14 16 18 20 22 24

Downwind distance (in hundreds of nm)

SOURCE Lawrence Livermore Laboratory

radioactive fallout. A survey of wind conditions for the proposed MPS deployment area

showed wind speeds at these altitudes that

averaged 30 to 40 knots, depending on season,

with a typical wind direction of 2500 to 290

i.e., from the west-southwest to westnorthwest. FinalIy, figure 56 shows the maximum width of radiation dose contours with

differing windspeed for a given wind shear.

(This width occurs at approximately half of the

downwind range for a given dose.)

Civilian fatalities will depend on the prevailing winds, as well as the degree of protection

taken by the populace. The 50-percent fatality

level occurs at about 450 rads and the 90-percent fatality level occurs at about 600 rads.

(For our purposes, we use the rad and the rem,

for roentgen-equivalent man, itter Changeably. ) Second, the relation between exposed

radiation dose and the actual absorbed dose

depends on the degree of protection afforded

the population at the time of attack. This is

commonly expressed as a protection factor,

which is a direct proportionality between total

dose absorbed for a given state of protection

(e. g., in the basement of a house) and the dose

Figure 56.— Crosswind Distance v. Total Dose

4

WSEG model as modified by Ruotanen

3 Yield = 1,000KT

Wear= .4 MPH/Kilofeet

not-----

* $

-3 “-”~ :

“.,;;<% ;

1 1 1

.

-4

0 50 100 150 200 250 300 350 400 450 500

Crosswind distance (in nm)

SOURCE Lawrence Livermore Laboratory

collected without any protection, such as out

in the open. Typical protection factors vary

between one and 20 (see The Effects of Nuclear

Weapons, .3rd ., Samuel Glasstone and Philip

DoIan; Table 9.1 20)

An attack on MX in Nevada and Utah might

involve the detonations of 4,600 1-MT

weapons, spread over about 20,000 mi2. Based

on these graphs, total doses of 500 to 2,000

rads for such a nuclear attack, corresponding

to fatal doses for a protection factor of 1 to 4,

might occur at a range of 500 to perhaps 1,500

nautical miles from the origin of the attack,

and depending largely on wind speed. Going

back to figures 54 A, B, and C, depending on

wind direction as we I I as winds peed and

population protection, civilian fatalities could

range from less than 1 million to more than 20

million. For typical winds in a west or northwest direction, fatalities run from less than 5

milIion for a 500 nautical miIe lethal range, up

to 20 million to 30 million corresponding to

our high lethal range of 1,500 nautical miIes.

It is important to note that these figures indicate the expected fatalities due to an attack

83-4770-B1- B
106 MX Missile Basing

on the MX fields alone. However, it seems

probable that a Soviet attack on MX would be

likely to include Minuteman and Titan fields,

strategic bomber bases and submarines in port.

Because these existing targets are distributed

over a large area the added fallout related

fatalities due to the additional targets in the

MPS fields would have a likely range from less

than 1 million to 5 million. Total fatalities for

this limited counterforce attack have been estimated to range from 25 million to 50 million

people

For an MPS deployment in Northern Texas

and New Mexico, corresponding graphs of

population at risk are shown in figures 57A-D.

Windspeed and direction,for this area at relevant altitudes average 35 to 45 knots, and from

the west, 2750 - 2800, With these winds, a

nuclear attack might resuIt i n fatalities of 10

m i I I ion to 20 m i I I ion; however even a normal

shift of wind direction couId resuIt i n fataIities

of well over 40 million for an attack on MX/

MPS alone

Figure 57A.— MX in Texas and New Mexico:

Population Subject to Fallout v. Wind Direction

100 ‘

90 — Range: 500 nm

80 —

70 —

60 —

50 —

40 —

30 —

o 50 100 150 200 250 300 350

Wind direction (in degrees)

SOURCE Lawrence Livermore Laboratory

Figure 57B. —MX in Texas and New Mexico:

Population Subject to Fallout v. Wind Direction

100

90 . Range: 1,000 nm

80 —

70

60

.

40

o 50 100 150 200 250 300 350

Wind direction (in degrees)

SOURCE Lawrence Livermore Laboratory

Figure 57C.— MX in Texas and New Mexico:

Population Subject to Fallout v. Wind Direction

100

90 — Range: 1,500 nm

80 —

70

o 50 100 150 200 250 300 350

Wind direction (in degrees)

SOURCE Lawrence Livermore Laboratory
Ch. 2—Multiple Protective Shelters ● 107

Figure 57D.—MX in Texas and New Mexico:

Population Subject to Fallout v. Wind Direction

90

80

70

60

50

40

30

I

Range 2,000 n m

0 50 100 150 200 250

Wind direction (in degrees)

SOURCE Lawrence Livermore Laboratory

Results on civilian fatalities would

penal in part on the Soviet responses to

300 350

also deMPS If,

for example, the Soviets responded by building

more missiles, each carrying the same warhead

yields as before, then the resulting radiation

doses would go up proportionately, If however, the Soviets respond by fractionating their

warheads, i.e., increasing the numbers of warheads with diminished individual yields, then

total radiation dose would most Iikely go

down, and not up. This decrease occurs for two

reasons. First, fractionation customariIy reduces total yield, resulting in less radioactive

byproduct of the weapon. Secondly, a lower

yield weapon resuIts in a slightly lower altitude

for the radioactive mushroom cloud, and

hence less fallout range, This distinction can

be seen quantitatively by comparing the one

megaton case in figure 55 with the 500 and 250

kT cases shown in figures 58A&B.

Figure 58A .—Downwind Distance v.

Total Dose—500 KT

4

WSEG model as modified by Ruotanen

Yield = 500 KT

3 Shear =.4 MPH/Kilofeet

Wind speeds

—20 knot s

2 - ---- —30 knots

—40 knot s

—50 knot s

1 -

“

.

-2 -

-3 -

024 6 8 10 12 14 16 18 20 22 24

Downwind distance (in hundreds of nautical miles)

SOURCE Lawrence Livermore Laboratory

Figure 58B.—Downwind Distance v.

Total Dose—250 KT

4

3

2

1

0

-1

-2

-3

-4

WSEG model as modified by Ruotanen

Yield = 250 KT

Shear =.4 MPH/Kilofeet

Wind speeds

 —20 knot s

---- —30 knots

. . . . —40 knots

. —50 knots

 —60 knot s

0 2 4 6 8 10 12 14 16 18 20 22 2400

Downwind distance (in hundreds of nautical miles)

SOURCE Lawrence Livermore Laboratory
Chapter 3

BALLISTIC MISSILE DEFENSE
Chapter 3.— BALLISTIC MISSILE DEFENSE

Page

Overview . . . . . . . . . . . . . . . . . . . . .. ....111

Technical Possibilities for BMD . ......111

LoADS with MPS Basing. . ...........112

The Overlay and Layered Defense of

Silo-Based MX. . . . . . . . . . . . .......11 3

Other BMD Concepts . ..............11 3

The ABM Treaty . ..................11 3

Endoatmospheric Defense. . . ..........114

Technical Overview of

Endoatmospheric BAD. . . . . . . . . . . .114

LoADS With MPS Basing. . . . . ........118

Other Endo Concepts . ..............12 6

Exoatmospheric and Layered Defense. ...129

Technical Overview of Exo BMD .. ....129

The Overlayand Layered Defense of

Silo-BasedMX. . . . ...............13 1

History of BMD and the ABM Treaty .. ...139

The ABM Limitation Treaty . .........140

Application of ABM Treaty Provisions

to MX Defense. . .................14 1

Future ABM Limitation Negotiations ...142

LIST OF TABLES

Table No.

20. Army’s LoADSCost Estimate,

October1980 . . . . . . . . . . . . . .

LIST OF FIGURES

Figure No.

59.

60.

61.

62.

63.

64.

Comparison of Ballistic Missile

Defense Systems. . . . . . . . . . . . . .

Page

. . . . 125

Page

. . . . 112

LoADS Defense Unit Before

Breakout. . . . . . . . . . . . . . . . . . . . . . . .119

LoADSDefense Unit After Breakout. . .120

Overlay/Underlay Layered Defense

System . . . . . . . . . ...........0.....131

Sensitivity of Layered Defense

Performance to Overlay Leakage. . ...134

U.S. Defensive Arsenal Needed to

Assure l,OOO Surviving U.S. Reentry

Vehicles ., . . . . . . . . . . . . . . . . . . . . ..135
Chapter 3

BALLISTIC MISSILE DEFENSE

Ballistic missi

also called ant

terns —would seek

e defense (B MD) systems —

ballistic missile (ABM) sysk to ensure MX survivability

by destroying attacking reentry vehicles (RVS)

either in space or after they entered the atmosphere. Different BMD concepts can have

very different capabiIities and weaknesses

which suit them for different MX basing roles

Thus, it is important to keep clear the context

for which the defense is intended, i.e , whether

it is desired to defend a large number of multiple protective shelters (MPS) or a relatively

smaII number of siI os This chapter discusses

the technical aspects of the entire range of

endoatmospheric and exoatmospheric defense

systems but will concentrate on the two BMD

concepts most often discussed in the context

of a near-term decision regarding MX basing:

the Low-Altltude Defense System (LoADS),

which is suited for the role of enhancing the

survivability of MX in MPS; and the Overlay

component of a Layered Defense, appropriate

i n theory for defense of MX based i n conventional silos.

There have been many changes in the technical nature of BMD systems in the past decade regarding both systems concept and

underlying technology. Systems contemplated

today are quite different f rot-n those discussed

in the ABM debate of a decade ago. From a

technical point of view, therefore, the issues

relevant to that debate have been replaced by

a n entire I y new set of issues. Though there are

many paraIIels, intuitions based on previous

acquaintance with BMD will not always be

relevant — again from a purely technical point

of view — to the systems cent emplated today

OVERVIEW

Technical Possibilities for BMD

It is useful to distinguish BMD systems according to the altitude regime in which they

track their targets and make their intercepts,

since this Iargely dertermines the effectiveness

possible with such a system. Endoatmospheric — or “endo ” — defense systems perform

tracking and intercept within the sensible atmosphere, from the Earth’s surface to about

300,000-ft altitude, For various technical

reasons, U. S endo BMD efforts have concentrated lately on the low-altitude regime, below

about 50,000 ft Low-altitude endo systems

such as LoADS are Iimited to making a small

number of intercepts over a given defended

target If the number of targets is relatively

small, as in the case of silo basing, such defensive systems can only exact a small number of

RVS from the attacker Low-altitude systems by

themselves are therefore of limited value

unless the number of targets or aim points is

large, as with MPS basing. The very fact that

their goal — forcing the offense to target a

small number of RVS at each aim point instead

of one — is modest, means that low-altitude

systems do not

achieve this goaI

Exoat mospher

lave to perform very welI to

c — or “exe” – defenses track

and intercept RVS in space I n contrast to lowaltitude endo defenses, exo systems can in

principle intercept many RVS attacking the

same target Systems with an exo component

can therefore in theory defend a small number

of targets such as silo-based missiIes from a

large attack However, this more demanding

task means that an exo system must be very

good indeed to accomplish it. Thus, an exo

system —even when accompanied by an endo

system in a “Layered Defense” — must have a

higher performance to do its job than a lowaltitude system requires to do its more modest

job.

In addition to specifying the capabilities of

a BMD system, the altitude regime determines

the type of sensor and interceptor required,

111
112 ● MX Missile Basing

which in turn establishes the type of technology required for the system and its potential vulnerabilities (see fig. 59).

Endo systems normally employ groundbased radars and nuclear warheads to track

and destroy targets. Radar blackout caused by

nuclear detonations in the atmosphere is not a

crippling problem for low-altitude endo systems, as it is for high-altitude endo systems,

but it (along with other factors) imposes the

limitation discussed above that only a very

small number of intercepts can be made within

a small area. Operation in the dense air at low

altitudes means that it is very difficult for an

opponent to fool the defense with decoys.

Operation in space would allow exo defense

to make use of nonnuclear kill mechanisms

and the tactic of preferential defense. Multiple

kill vehicles can also be mounted on a single

interceptor missile, resulting in some savings

given the cost of boosting defensive vehicles

into space in the first place. Infrared sensors

are preferable to radars for exo defense. Without the filtering effect of dense air within the

atmosphere, exo sensors are vulnerable to offensive tactics making use of decoys and other

penetration aids.

LoADS With MPS Basing

This use of BMD would be an alternative to

increasing the number of shelters in an MPS

system in the face of a growing Soviet threat.

In the Air Force baseline horizontal MPS system, for example, a LoADS defense unit would

be hidden in one of the 23 shelters in each

cluster and programed to intercept the first RV

approaching the shelter containing the MX

missile. Since the Soviets would be presumed

not tO know which shelter contained the MX,

they would have to assume for targeting purposes that each of the 23 shelters contained an

MX missile defended by LoADS. If the defense

were only able to intercept one RV over each

defended shelter, the Soviets would have to

target two RVS at each shelter instead of one.

Thus, LoADS would increase the attack price

for an MX missile from 23 to 46 Soviet RVS.

It is possible to have high confidence that

LoAIDS could exact this price of 2 RVS per

shelter if the locations of the LoADS defense

unit; and the MX missiles could be concealed

and if the defense unit could be hardened to

survive the effects of nearby nuclear detonations. This confidence, conditional on successful deception and nuclear hardness, results

both from advances in BMD technology in the

last decade and from LoADS’ relatively

moclest goal of exacting from the Soviets one

more RV per aim point.

Preservation of location uncertainty (PLU)

would be made more difficult with the addition of LoADS to the MPS system, since the

LOADS ,defense unit, MX missile, and simuFigure 59.—Comparison of Ballistic Missile

Defense Systems

“Exo” atmospheric “Endo” atmospheric

defense defense

r

Safeguard

Overlay

oparating

area space atomosphere atmosphere

Type of

of sensor

KIH

mechanism Non-Nuclear Nuclear Nuclea r

SOURCE Office of Technology Assessment
Ch. 3—Ballistic Missile Defense ● 113

Iator must all have indistinguishable sig -

natures. The nuclear effects requirements for

LoADS are unprecedented. The design goals of

PLU and hardening must furthermore be met

simultaneously. It is not possible to have confidence that these goals can be met until

detailed design and testing are done,

In addition to PLU and hardness, there are

stylized attacks or “reactive threats” which

could pose a long-term threat to LoADS. These

risks are judged moderate,

The Overlay and Layered Defense

of Silo-Based MX

The Army’s concept of Exo defense, called

the Overlay, would consist of interceptors,

about the size of offensive missiles, launched

into space from silos. Each interceptor would

carry several kill vehicles that would be dispatched, using infrared sensing, to destroy attacking RVS before they entered the atmosphere. The Overlay could be deployed with an

endo “Underlay” to make a Layered Defense

of silo-based MX.

High efficiency would be required of the

Overlay if it was to be able to defend a small

number of MX silos against a large Soviet attack. The Overlay is in the technology exploration stage, and there is no detailed system

design such as exists for LoADS. There are

many uncertainties about whether the Overlay

couId achieve the high level of performance it

would require to satisfy the needs of MX basing. These uncertainties concern both the

underlying technology and the defense system

as a whole. In addition, there is a potential

“Achilles’ heel” in the vulnerability of the

Overlay to decoys and other penetration aids.

For the moment it would be quite risky to

rely on the Overlay or Layered Defense as the

basis for MX survivability.

Other BMD Concepts

This chapter will also discuss briefly other

BMD concepts which have been studied,

A concept called “Dust,” “Environmental,”

or “Ejecta” defense involves burying “clean”

nuclear weapons in the vicinity of missile silos.

The bombs would be exploded on warning of a

Soviet attack, filling the air with dust which

would destroy Soviet RVs before they reached

the ground. Though there is little technical

doubt about the high effectiveness of dust

defense, there is considerable concern about

public reaction to plans for the deliberate

detonation of nuclear weapons on U.S. territory.

Various low-altitude or “last-ditch” concepts based on simple or “novel” principles

have been proposed. Though perhaps relevant

for other BMD roles, these concepts do not appear to have an application in MX defense,

given the requirement to preserve a small

number of MX missiles against a large number

of Soviet RVS.

The Army’s Site Defense is a derivative of

the Sprint component of the Safeguard defense system of a decade ago. Based on the

technology of the 1970’s, Site Defense is preserved as an option in the event of a decision

to field a BMD system based on known technology in a short period of time. Though inadequate for the role of MX defense, Site Defense could be appropriate for other limited

BMD roles.

The ABM Treaty

The 1972 ABM Limitation Treaty was negotiated as part of the SALT I package of strategic arms limitation agreements. A Protocol

specifying further I imitations was signed in

1974. The Treaty is of unlimited duration but is

subject to review every 5 years. In addition, the

Standing Consultative Commission created by

the Treaty meets about every 6 months to review implementation of the provisions of the

Treaty and to consider such matters as ‘the

parties might wish to raise.

Briefly, the Treaty and Protocol allow development of some types of ABM systems but

limit their deployment to small numbers at
114 ● MX Missile Basing

specified sites. Development of other types of

ABM beyond the laboratory is forbidden

altogether.

No meaningful defense of MX missiles,

either in silos or MPS, would be permitted

within the Treaty, since any such deployment

could consist of at most 20 radars (18 small, 2

large) and 100 interceptors confined to the

vicinity of Grand Forks, N. Dak., or Washington, DC.

Limitations on development constrain the

types of ABM work that can pass beyond the

laboratory stage. Since LoADS consists of

radars and interceptors of the kind permitted

by the Treaty, development of this system can

proceed without abrogation or renegotiation

of the Treaty except where such development

concerns the specific features of mobility,

more than one interceptor per launcher, or a

hypothetical reload capability. Development

of the Overlay interceptors can proceed to the

extent of testing single kill vehicles on interceptors, but development of multiple kill

vehicles outside of the laboratory is forbidden. ‘

Development of space-, sea-, or air-borne ABM

system components outside of the laboratory

is also forbidden. The Treaty specifies that development of ABM systems based on “new

technologies” unforeseen or unspecified at the

time the treaty was drafted cannot be

deployed.

ENDOATMOSPHERIC DEFENSE

Technical Overview of

Endoatmospheric BMD

Endoatmospheric —or “endo” – defense systems perform tracking and intercept within the

sensible atmosphere, from the Earth’s surface

to about 300,000-ft altitude. It is important to

distinguish high-altitude systems, which acquire and track their targets above about

100,000 ft, from low-altitude systems, which

track and engage below 50,000 ft. The Sprint

component of the Safeguard system is an example of the former type and the Army’s present LoADS concept is an example of the latter.

Endoatmospheric defense normally employs

ground-based radars for tracking. Optical or infrared sensors would be inappropriate for endo

operation because, among other reasons, they

cannot supply accurate range information and

low cloud cover or dust could obscure their

view of incoming RVS.

Nonnuclear kill is possible in the atmosphere, but nuclear warheads provide a

more certain kill mechanism. A nonnuclear kill

wouId require that the radar provide very accurate trajectory information to the interceptor or that the interceptor have its own sensor.

Because the kill radius of a nuclear warhead is

much greater, less accurate information suff ices to guarantee RV destruction.

Neutrons released from a defensive nuclear

warhead provide the mechanism for disabling

the offensive RV. An RV warhead contains fissionable material that absorbs neutrons very

readily: this is the property that allows the

nuclear chain react ion to proceed when the RV

is detonated. When the fissionable material in

an incoming RV absorbed the neutrons from

the defensive warhead, it would be rendered

unable to detonate. Physical destruction of the

RV would therefore not be necessary: though

blast from the defensive warhead could play a

role, it is a less certain kill mechanism. The

neutron kill is sure because the incoming RV

must contain neutron-absorbing material to do

its job, and it is very difficult to shield against

neutrons. A relatively low-yield defensive warhead (tens of kilotons) could generate a neutron fIuence lethal to RVS at ranges of several

hundred feet from its detonation point. The

defensive interceptor therefore would not

have to be very accurate to ensure disabling of

the RV.

Use of nuclear interceptors does involve

special procedures for their release, however.

Release of offensive nuclear weapons must be
Ch. 3—Ballistic Missile Defense ● 115

authorized by the National Command Authorities. The procedures for defensive nuclear

release have not been worked out since the

United States has no deployed, working BMD

system.

Vulnerabilities of High-Altitude

Endo Defense

The radar for the endoatmospheric Sprint

component of Safeguard tracked incoming

RVS above 100,000-ft altitude, Because of a

number of technical problems associated with

such high-altitude operation, U.S. BMD efforts

in recent times have tended to focus on the

low-altitude regime below 50,000 ft.

Target tracking and discrimination at high

altitudes requires radars which are large and

expensive, These radars, which must for cost

reasons be few in number, would make tempting targets for a concentrated precursor attack

designed to overwhelm the defense in the area

of the radars and penetrate to destroy them.

The defense system would then be blind.

I n addition to the vulnerability of the radars,

high-altitude endo defense suffers from two

crucial technical problems: target discrimination and radar blackout. Discrimination

refers to the ability to distinguish RVS from the

bus and tank fragments which accompany

them and from light decoys or other penetration aids which an attacker could design to

confuse the defense. The defense would waste

costly interceptors if the radar mistook a

decoy or other object for an RV, and an RV

would leak through if it were mistaken for a

nonlethal object. High-altitude systems like

the Sprint component of Safeguard would

have high wastage and leakage because of the

intrinsic difficulty of radar discrimination in

the upper atmosphere. In the thin air at high

altitudes, objects reentering the atmosphere

without heat shields, such as bus fragments,

have not yet started to burn up, and light

decoys fall at the same rate as heavier RVS

The dense air in the lower atmosphere, on the

other hand, acts like a filter: unshielded objects burn up, and light shielded objects slow

down. I n either case the heavy shielded RV can

be distinguished after it has reached low

altitudes.

Blackout occurs when the heat and radiation from a nuclear explosion ionize the surrounding volume of air. This ionization causes

attenuation and reflection of radar signals

passing through the affected region. At the

high altitudes where the Safeguard radars

tracked their targets, blackout over large areas

of the sky could be created by a rather small

number of detonations. An attacker was therefore encouraged to launch a first salvo of warheads fuzed to detonate at high altitudes,

thereby blacking out the defense’s radars. The

nuclear warheads on the defense’s own interceptors could also produce this effect. The attacker could then bring in his main attack

behind the protective blackout “shield.”

Advantages and Limitations of

Low-Altitude Endo Defense

Because of the vulnerability and cost of the

radars and the severe technical problems of

discrimination and blackout for high-altitude

endo systems, U.S. efforts in endo defense

have tended to focus on low-altitude systems,

which track targets and perform intercepts

below 50,000 ft.

Low-altitude systems are relatively impervious to decoy attack because it is possible to

assess the weight of a body falling through

dense air from its radar return. Weight is a

strategically significant discriminant, since offensive boosters have limited throwweight. Beyond a certain point, loading decoys onto a

missile requires offloading RVS, a trade that

becomes unfavorable for the offense if the decoys must be heavy in order to fool the defense, The trade is clearly absurd (leaving aside

the fact that a decoy might be cheaper than an

RV) if the decoy must be as heavy as the RV

itself, for the RV at least stands a chance

of penetrating the defense and exploding

whereas the decoy does not.

The procedure by which a low-altitude radar

obtains a falling object’s weight is difficult for

even the cleverest decoy designer to sidestep
116 ● MX Missile Basing

because it is based on fundamental principles

which is not within the power of the offense to

alter: the presence of dense air at low altitudes and some basic laws of physics. The rate

of fall of an object — RV, decoy, bus fragment,

etc. —through the atmosphere is determined

by the ratio of its weight to its area, called its

ballistic coefficient, The higher the ballistic

coefficient, the faster the object falls. Of two

objects of equal area, the heavier will fall

faster because it has more force of gravity to

overcome the resistance, or drag, of the air. of

two objects of equal weight, the smaller or

more streamlined will fall faster because it

does not have to push as much air out of its

way. Thus, a flat sheet of paper falls slowly

whereas the same sheet, when balled up, drops

rapidly.

By tracking an object, a radar can measure

its rate of slowdown and therefore the ratio of

its weight to its area. In the thin air at high

altitudes, however, differences in ballistic

coefficient do not lead to large differences in

rate of fall because there is not much drag. At

low altitudes the differences are quite pronounced. Thus, discrimination on the basis of

ballistic coefficient is more reliable at low

altitudes.

Measuring the ballistic coefficient might not

be sufficient for discrimination, however, since

a small light decoy could have the same ballistic coefficient as a large heavy RV. It would

in fact be quite difficult to design decoys

which matched the balIistic coefficient of an

RV at low altitudes since the shape of the RV

(and hence its ballistic coefficient) changes in

a complex way as its heat shield ablates. But as

a hedge against a very carefully designed

decoy, the defensive radar can employ another

technique, involving the disturbance made in

the air as the body passes through it, to obtain

the area of the falling body. Combining the

area with the ballistic coefficient gives the

body’s weight, a quantity that is not in the interest of the offense to match. Thus a lowaltitude defense system which made use of

these radar discrimination techniques would

be virtually impossible to sidestep with

decoys, since the fundamental discriminant is

weight and the techniques rely on the basic

properties of gravity and hydrodynamics.

Radar blackout is not a crippling problem

for low-altitude systems as it is for highaltitude systems.

However, fireball effects impose a basic

limitation on the effectiveness of low-altitude

defenses. The ability of low-altitude or “deep

endo” systems such as LoADS to make multiple intercepts within a short time over the

same site — a conventional missile silo or a

shelter in an MPS system — is severely constrained, no matter how many interceptors the

defense deploys. This limitation arises both

from blackout in the regions of nuclear fireballs and from trajectory perturbations suffered by follow-on RVS passing through these

regions. The technical nature of this problem,

and the extent of the I imitations it imposes, are

discussed further in the Classified Annex. Even

if a hypothetical future technology allowed

the defense to overcome this fundamental

Iimitation, there might still be strategies

available to the attacker that were more efficient than saturation, such as precursor attack

on the defense itself or use of various penetration techniques.

How Good is Good Enough?

It is an important feature of low-altitude

systems that only aim to make an attacker

target one more RV at each aimpoint that they

do not have to be very capable to force an attacker to pay this price. In fact, if the defense

is only good enough that it succeeds in making

its single intercept more often than it fails —

how much more often is irrelevant–the attacker will conclude that he makes better use

of his RVS by targeting two RVS at a lesser

number of defended aimpoints than by targeting one RV each at a larger number. The attacker’s conclusion is not a result of conservative offensive perceptions but of sober

caIcuIation.

To take an explicit, if oversimplified, example, suppose an attacker has 1,000 RVS to

target at 1,000 aim points, each of which is

defended by a defense system whose goal is a
Ch. 3—Ballistic Missile Defense ● 117

single intercept per aimpoint. Suppose also

that the defense performs so poorly that it succeeds in making an intercept only 51 percent

of the time and fails 49 percent of the time.

The attacker has the choice of targeting all

1,000 aimpoints with one RV (Case 1) or 500

aimpoints with two RVS (Case 2). In Case 1, the

attack destroys 490 aim points because the defense fails this many times. In Case 2, all 500

aimpoints targeted 2-on-1 are destroyed by

assumption. Thus the attacker concludes that

he actually does better by “doubling up” on a

smaller number of aimpoints (Case 2). But this

is exactly what the defense seeks to force him

to conclude.

Therefore, if the odds that a single-shot

system actually makes its intercept are greater

than 50 percent, it achieves its goal of forcing

the attacker to target one more RV at each

a impoint. Whether the odds are 51 or 99 percent is immaterial, since the offense does not

have the option of targeting fractions of RVS at

each aimpoint, but only one or two.

Once the limited single-shot goal is accepted, a relatively poor system is as good as a

perfect one. Although low-altitude endo interception is a very challenging task, defense

systems do not have to perform it very well if

they accept a goal of only one intercept per

aimpoint. This stands i n contrast to exo defenses, which aspire to a higher attack price

than one RV per aimpoint. Such defenses are

not worthwhile unless their performance is

very good.

In the example above, the attacker was

given the choice between l-on-l and 2-on-1

targeting of ballistic reentry vehicles. Stylized

attacks or “reactive threats” involving nonballistic RVS, precursor barrages, radar interference, etc. pose another set of challenges

to single-shot defenses which must be analyzed on a case-by-case basis.

The Need for Leverage

A generic low-altitude defensive system that

couId only claim a single RV per defended site

would not be effective unless some additional

defensive leverage could be found. One U.S.

defense unit (radar plus interceptor) would be

a poor cost trade for a single Soviet RV unless

intercept of this single RV resuIted in the survival of a defended target valuable to the

United States. But this would only be the case

if the number of targets were so large that the

Soviets could not afford to target multiple RVS

at each one. If the number of targets were

small, the Soviets could attack each with

multiple RVS, overwhelm the defense, and destroy the U.S. value at an extra price, relative

to the undefended case, of a small number of

RVS. For instance, 100 single-shot low-altitude

defense units defending 100 silos containing

MX missiles would only be able to claim 100

RVS from a Soviet arsenal of thousands.

Additional leverage for the low-altitude defense could be provided in three ways.

Deceptive basing, such as for LoADS in association with MPS, would allow a small number

of defense units to force the Soviets to expend

a large number of RVS because they would not

know which shelters were defended and would

have to assume that all 4,600 shelters contained MX missiles defended by LoADS.

Therefore, 200 LoADS defense units capable of

a single intercept each would be able to exact

a price of 4,600 RVS, forcing the Soviets to attack each shelter twice for a total of 9,200 RVS.

A so-called “cheap” or “simple” defense

system such as Swarm jet, to be discussed later,

could conceivably improve the cost tradeoff

for single-shot defense, but the overall attack

price would still be small if the number of

defended targets was small, as with silo basing.

If the simple system were very inexpensive,

one could conceive of deploying one defense

unit with each shelter in a MPS system. This

would have the same effect as deceptive basing without the need for PLU. There does not

as yet appear to be a simple interception

system cheap enough to allow this possibility.

However, dust defense could be cheap enough

to deploy in this way.

Last, a capable “Overlay” defense operating

outside of the atmosphere would also be a

powerful source of leverage for an associated

“Underlay” endo defense. The Overlay (if ef-
118 ● MX Missile Basing

fective) would thin the attack and break up the

structured Iaydowns of RVS needed to

penetrate the Underlay. The Soviets would

have to target many RVS at each defended site

in order that a few leaked through in the right

sequence to penetrate the Underlay. Such an

attack strategy based upon leakage through

the Overlay would be costly of RVS and exceedingly risky for the attacker.

Because of the need for extra leverage, proposals of low-altitude defense for MX missiles

have focused on deceptive low-altitude defense for a many-aimpoint MPS basing system

or on Overlay/Underlay (Layered] defense for a

force of MX missiles deployed in a small number of conventional silos.

LoADS With MPS Basing

LoADS Description

THE DEFENSE UNIT (DU)

The LoADS defense unit (DU) would consist

of a radar, data-processor, and interceptor

missiles. The radar would be of the phasedarray type, operating at high frequencies and

with high power and narrow beamwidth for extra anti jam capability. The data processor

would employ distributed processing for rapid

throughput of large amounts of trajectory

data. The interceptor missiles, roughly one

quarter the length of an MX missile and half as

wide, would be capable of extremely high accelerations and rapid change of direction, The

inertially guided interceptor would be directed

at launch towards a predicted impact point

with the RV but its course could be updated in

flight as well. The interceptor would be armed

with a low-yield nuclear warhead. The

technologies embodied in these elements of

the DU represent significant advances beyond

earlier U.S. endo BMD systems.

For the purpose of LoADS/MPS combination

basing, the elements of the DU would be

packaged into cylinders capable of fitting into

the same spaces in the shelters and transporters occupied by the MX missiles and simulators (see fig. 60). The DU, MX cannister, and

simulator would be so designed that they presented identical signatures to sensors which

the Soviets might use to distinguish them in the

shelters or in transit, It would be essential to

the effectiveness of the LoADS/MPS combination that it be impossible to distinguish

MX, DU, and simulator.

One DU would be deceptively emplaced in

each cluster of 23 shelters, along with the MX

missile and 21 simulators. The DU would be

programed to defend the shelter containing

the MX missile. Upon receiving warning of a

Soviet attack, the DU would erect vertically,

pushing the radar face and the interceptor cannister through the roof of the shelter (see fig,

61). The DU would then be ready to defend the

shelter containing the MX. Breakout would be

an irreversible process, since it would destroy

the roof of the shelter. Various schemes have

been studied to avoid breakout. For instance,

the DU could roll out the door of the shelter

and erect like the MX missile. But the DU in

this exposed position would be too vulnerable

to destructive effects of nearby nuclear

detonations. The broken-out DU would still

have the protective shielding and structural

support of the remainder of the shelter.

It would be absolutely essential that the

defense received adequate warning that Soviet

RVS were approaching so that it could awake

electronic equipment from its dormpnt state

and break out. It appears that this process of

readying the LoADS DU could be performed in

a short period of time. If achievable, this

wouId mean that it would not be necessary to

have warning sensors which detected a Soviet

attack at the moment of launch, but only as

the attacking RVS approached the United

States. This late warning would be easier to

provide than the early warning required to support launch under attack or exo BMD. It would

also be easier to protect warning sensors of

this type from a Soviet precursor attack. it

might also be desirable to have some information ,about the size of the attack before a decision were made to break out. (This is discussed

further in the context of Shoot-Look-Shoot in

the Classified Annex. ) Finally, the command,

control, and communications to support timely breakout would require procedures and

hard\ware immune to a determined Soviet ef-
Ch. 3—Ballistic Missile Defense ● 119

Figure 60.— LoADS Defense Unit Before

Breakout (human figure indicates scale)

Radar Batteries Data processing Interceptors

SOURCE Office of Technology Assessment

fort to disrupt them. Several technically feasible approaches to these problems have been

proposed, and their provision would be essential to effective defense.

LoADS OPERATION

The LoADS DU in each cluster would be programed to defend the shelter containing the

MX missile, Since the Soviets would not know

which shelter contained the MX if PLU were

maintained, they would have to assume for

targeting purposes that each of the 23 shelters

contained an MX missile defended by LoADS

LoADS would intercept the first RV attacking

the MX shelter, so the Soviets would have to

target each shelter twice in order to destroy the

MX. LoADS would double the price the Soviets

wouId have to pay for an MX missile from 23 to

46 RVS. Thus U.S. deployment of LoADS would

be essentially equivalent to doubling the number of shelters in the MPS deployment while

keeping the number of missiles the same.

deployment while keeping the number of

missiles the same.

It is desirable for each DU to have more

than one interceptor in order that it could defend itself if it came under attack before the

MX shelter did.

It would be essential that the location of the

MX be unknown to the Soviets. It would also

be necessary to conceal the location of the

DU, since if this were known the Soviets could

attack the defense first, forcing it to use up its

interceptors in self defense, Subsequent attack

on the other shelters would find them undefended.

LoADS WITH VARIANTS OF MPS

The operation of LoADS would be essentially unchanged if the MPS deployment were

organized into “valley clusters” containing

several missiles instead of discrete clusters of
120 ● MX Missile Basing

Figure 61 .— LoADS Defense Unit After

Breakout (human figure indicates scale)

SOURCE Office of Technology Assessment

23 shelters for each missile. A DU could still be

provided to defend each missile, and the attack price per missile would again be doubled.

From the point of view of LoADS defense,

there would be significant tradeoffs between

horizontal and vertical shelter deployment but

no clear reason to prefer one to the other. For

vertical shelters, it would be necessary to put

the radar and missile cannister in different

shelters, since they would be too large to fit

side-by-side in a single shelter. There would

have to be a data link to connect the two

elements of the defense unit. Since the units

would be moved from shelter to shelter periodically, the communications equipment

would have to connect all pairs of shelters,

potentially a costly addition. The links would

furthermore have to be resistant to disruption

from nuclear effects. On the other hand,

breakout would not be required, since the defense could egress through the blast door of

the vertical shelter. Matching four objects (MX,

simulator, radar module, and interceptor cannister) would be more difficult than three, but

there would be more design flexibility for the

separate radar module and interceptor cannister because each would be, so to speak,

“half empty. ” The extra room could be used

for PLU countermeasures. Protecting the DU

elements from nuclear effects could conceivably be easier for vertical shelter deployment.

It is not possible at this time to assess these

tradeoffs in detail, but it is not apparent that

either vertical or horizontal offers clear advantages. More study has been made of the

horizontal alternative.
Ch. 3—Ballistic Missile Defense 121

LoADS Effectiveness

Active defense systems are very complex:

the interception process is complicated, with

many distinct sources of leakage and wastage.

There are many attack scenarios, offensive

countermeasures, and defensive countercountermeasures to consider Analysis of the

effectiveness of a BMD system can therefore

be more involved than analysis of basing

systems that ensure survival of MX by passive

means such as mobiIity, concealment, or

deception It is therefore important in assessing how well LoADS would do its job to be very

clear what that job is

Suppose LoADS sought to double the price

the Soviets would have to pay to destroy an

MX missile from 23 RVs to 46 RVs, In this case,

LoADS would have the rather modest task of

intercepting the first RV targeted at the MX

missiIe within each cluster I n order to destroy

the MX missile within a cluster, the Soviets

would have to target two RVS, or “double up, ”

at each shelter, This assumes that PLU would

be successful and the Soviets would have no

knowledge of the location of the MX or the

DU.

In fact, LoADS could exact the price of 2

RVS per shelter even if the defense system

were rather inefficient. Roughly speaking, if

the Soviets believed that LoADS would successfully intercept the first RV targeted at the

MX shelter more than half of the time— that is,

if the efficiency of LoADS were greater than

only 50 percent — then the Soviets would

calculate that they made better use of their

RVS by doubling up on fewer shelters than by

targeting many shelters with one RV,

For example, suppose that the Soviets had

6,900 RVS to target at 4,600 MPS shelters,

(These numbers are chosen to make the arithmetic easy and for no other reason, ) Suppose

also that LoADS were only 51-percent efficient

in a 1 -on-1 attack: that is, if one RV were

directed against every shelter, LoADS would

successfully intercept 51 percent of the RVS

directed at the shelters containing MX. This is

the same as a leakage of 49 percent. Assume

also that all targeted Soviet RVS actually

arrived on target and further that if two RVS arrived at the MX shelter within a short space of

time, LoADS would not even attempt to intercept the second and the MX missile would be

destroyed,

The Soviets would have the choice of using

their 6,900 RVS either to target 100 clusters

(2,300 shelters) with one RV and 100 clusters

(2,300 shelters) with two RVS (Case 1 ) or to double up on 150 clusters (3,450 shelters) and leave

50 clusters (1,150 shelters) untouched (Case 2).

In Case 1, all 100 MX missiles targeted 2-on-1

wouId be destroyed, and 49 of the missiles

targeted l-on-l would be destroyed because

LoADS would only be 51-percent efficient by

assumption. Thus in Case 1 the Soviets wouId

destroy 149 MX missiles, In Case 2, the 150

missiles targeted 2-on-1 would be destroyed

and the remaining 50 untouched The Soviets

wouId therefore actualIy destroy more MX missiles by doubling up (Case 2), even though

LoADS failed to make an intercept almost as

many times as it succeeded.

It therefore appears that LoADS would not

have to be very efficient to exact a price of

two RVS from the Soviets. At the same time, it

wouId be exceedingly difficuIt to exact a price

of several RVS.

So far, the analysis has considered only simple 1 -on-1 or 2-on-1 attacks. The conclusion is

that, as far as these attacks are concerned, and

assuming the DU survives nuclear effects to do

its job and that PLU is maintained, it is possible

to have confidence that LoADS is capable of

its job. Although low-altitude interception of

RVS is a very challenging technical task, and

there are many uncertainties about LoADS operation and potential contributors to inefficiency (radar and interceptor performance, RV

radar cross sections, radar traffic handling,

kill mechanisms, etc.), there are none which

should stop LoADS from doing its job as well

as it needs to,

If the defense only sought to make one intercept over the MX shelter, then the United

States could assume that the Soviets would

pay the price of 46 RVS per MX missile if given

the choice of l-on-l or 2-on-1 targeting. Could
122 ● MX Missile Basing

they do better by using special attac k

strategies?

There are many such reactive threats to

LoADS, For instance, decoys are a hypothetical threat: precision decoys seek to fool

the radar into intercepting them, while traffic

decoys simply aim to fool the radar long

enough to consume precious data-processing

time. As discussed in the Technical Overview,

the ability of radar to weigh falling objects at

low altitudes means that decoys are probably

not a serious threat to LoADS. Jammers deployed along with attacking RVS could seek to

blind the radars. Maneuverable reentry vehicles (Ma RVs) could try to evade the interceptor; and if MaRVs were provided with

radar- homing devices, they might destroy the

LoADS defense units before they had done

their job. These reactive threats are discussed

in the Classified Annex. Defense barrage,

blackout, and exhaustion attacks are discussed

under Hardness to Nuclear Effects and its Classified Annex, and Spoof and Shoot-LookShoot, both threats to deception, are discussed

under Preservation of Location Uncertainty

[PLU) and its Classified Annex.

One can raise legitimate questions as to

whether a prudent Soviet planner would use

any of these techniques to sidestep LoADS, but

the defensive planner must fortify the system

design against all of them. The attractiveness

of these special threats to Soviet planners

would presumably be weighed against the

benefits they would derive from the simple expedient of deploying two Soviet RVS for every

U.S. shelter. Detailed analysis of these special

threats, presented elsewhere in this report or

its Classified Annexes, indicates that some of

them are worrisome and represent a long-term

risk to the effectiveness of LoADS/MPS.

Hardness to Nuclear Effects

The close shelter spacing–1 mile–means

that LoADS must operate in a nuclear environment of a severity unprecedented for so

complex and exposed a piece of equipment.

Failure to meet the requirements could lead to

pronounced degradation in system performance. It is also vital that measures taken to protect the DU do not betray its location, i.e.,

break PLU. Providing for nuclear hardness requires detailed understanding of the expected

nuclear environment and its effect on critical

mechanical and electrical components. Especially important for LoADS, given the unprecedented character of the hardness requirements, is testing of actual equipment. DU design and nuclear effects analysis—and, in the

case of LoADS, PLU analysis — must proceed in

concert. These studies are just beginning. Testing is required before it wilI be possible to have

confidence that LoADS can meet its hardening

needs, especialIy within the severe design constraints imposed by PLU.

AS with the analysis of system effectiveness,

it is important to have a clear idea of LoADS’

hardening needs and of the consequences of

failing to meet these needs. The key requirements concern the survival of the DU, and

especially the radar, after it has broken out of

the shelter and is waiting to intercept the RV

targeted at the MX shelter. Other concerns,

probably less serious, are the hardness of the

interceptor as it flies to make its intercept and

the hardness of the DU before it breaks out.

HARDNESS OF THE DU AFTER BREAKOUT

For LoADS to do a single-shot job, no less

than 46 Soviet RVS may suffice to destroy an

MX missile. The attacker must either be made

to fail to destroy the DU before it has made its

intercept or be made to pay a heavy enough

price to destroy the DU that nothing is gained

by trying.

The hardness of the broken-out DU defines a

“keep-out zone” around the unit: RVS which

detonate within the keep-out zone are assumed to destroy the DU and must be intercepted if they arrive before the DU has made

its intercept above the MX shelter. It is for selfdefense that each DU should contain more

than one interceptor missile.

Inadequate nuclear hardening would mean

that the keep-out zone was too large. An illustrative, if presumably exaggerated, example

consists of a DU so soft that a detonation

anywhere within its shelter cluster would im-
Ch. 3—Ballistic Missile Defense ● 123

pair its function. In this case, the Soviets could

target a few RVS (perhaps of higher yield than

those targeted at shelters) to arrive at random

locations within each cluster a few seconds

before arrival of the main attack. The main attack would consist of one RV on each shelter.

The DU would have no choice but to intercept

all of the precursors, for otherwise it wouId be

rendered inoperable, If there were as many

precursor RVS as interceptors in the DU, then

all the interceptors would be used up in selfdefense, The main attack would then find the

cluster undefended, as though LoADS did not

exist. The attacker would then have paid not

46 RVS, but rather the undefended price of 23

RVS plus just a few additional RVS to exhaust

the defense,

The defense suppression barrage described

above is one of several scenarios where LoADS

hardness plays a crucial role, In all of these

scenarios, the attacker seeks to destroy an MX

missile for an attack price of less than 46 RVS,

The results of a more detailed analysis, presented in the Classified Annex, indicates that

the 1-mile shelter spacing imposes severe requirements on the DU. Unlike the MX missile,

protected by its steel and concrete shelter and

several feet of earth, the DU is directly exposed to the nuclear effects. Not only must the

DU survive, but its complex components must

function through the attack. Thus, some

effects— prompt radiation, certain effects of

electromagnetic pulse (EM P), dust, etc. —

which are not important for missiIe protection

are severe threats to LoADS. Defense performance, measured by vulnerability to these

stylized attacks, might be degraded appreciably by shortcomings in hardening.

Work on LoADS hardening so far has concentrated upon defining quantitatively the

nuclear effects which the DU must be able to

endure, not providing design fixes for potential

vulnerabilities, Even defining the effects will

require testing, since in some respects they exceed the predictive power of computer simulation codes. Understanding the interaction or

“coupling” of these effects to the peculiar

geometry of the broken-out DU, to electronics,

and to radar performance wiII also require

testing.

Nothing that is done to ensure its hardness

must permit the DU to be detected when it is in

the shelter. If the Soviets were able to detect

which shelter contained the DU, they could

target that shelter with a few precursors, forcing it to exhaust itself in self-defense. This and

other threats to PLU are discussed in the next

section. The important point is that hardening

the DU —adding shielding, structural support,

etc. — must not provide a signature which

would allow the Soviets to detect the DU’S

location. This synergism of hardness and PLU

is a matter of testing and detailed design which

has not yet been done.

Ensuring adequate hardness for the brokenout DU is thus a chalIenging task, and it wiII require some time ‘before uncertainties can be

reduced to levels where a final judgment is

possible.

It is important finally to note the constraints

that would act upon the offense if it were to

seek to exploit potential vulnerabilities in

LoADS. If the Soviets were to fractionate so as

to be able to target as many shelters as possible, they would have to reduce the yields of

their RVS. The lower yields would significantly

alleviate the nuclear effects on LoADS in

some, though not all, circumstances. If on the

other hand, the Soviets kept their yields high

with the aim of exploiting potential LoADS

vulnerabilities, it would be difficult for them

to fractionate their missiIes,

HARDNESS OF THE IN-FLIGHT INTERCEPTOR

As the missile flew towards its intercept

point, it would be buffeted by the shock waves

from nearby detonations. Though the interceptor has the ability to correct its course, it

has a limited duration of powered flight. If

intercepting an RV at a relatively distant point,

burnout would be complete before the interceptor reached the RV, When coasting in this

way, it would have less ability to correct its

course than when burning.

Interference with interceptor performance

due to nuclear effects such as shock waves is
124 ● MX Missile Basing

one of the many contributors to system

leakage. As described in the previous section,

LoADS can tolerate a large leakage without

impairing its overall effectiveness. Thus inflight nuclear effects might not serve to increase leakage above an acceptable point.

However, interceptors flying out to attempt

multiple intercepts would be forced to fly in a

severely disturbed environment.

HARDNESS OF THE DU IN THE SHELTER

In the context of a Spoof or Shoot-LookShoot attack, to be discussed in the next section, the DU might be required to survive a

Iight precursor attack before it broke out of its

shelter. I n this situation the DU would be

relatively secure because it would be in the

shelter and the scenario cal Is for a Iight attack.

Additional discussion of the problems with

meeting LoADS’ nuclear hardening requirements can be found in the Classified Annex.

Preservation of Location Uncertainty (PLU)

Successful deception is vital to LoADS’

defensive leverage. If the location of the DU

were known to the Soviets, they could exhaust

the defense with a precursor attack. A subsequent one-on-one attack would find the

shelters completely undefended, What is

more, under certain circumstances, a breakdown of PLU for the LoADS DUS could cause a

breakdown of PLU for the MX missiles as well.

In this case, the United States would be worse

off than if there were no defense at all.

For undefended NIPS, PLU appears to be a

complex and challenging technical enterprise,

but no signatures of the MX missile have been

identified which present clearly insurmountable problems. PLU for the LoADS/MPS combination has not yet progressed this far, and

the problem will have to be reduced to a comparable “acceptable” level of detail. In particular, the design requirements imposed by

nuclear hardening must be taken into account.

Even if no “Achilles’ heel, ” or gross

signature of the DU which is fundamentally incompatible with PLU, is found, a complex

engineering task faces the LoADS designer. In

the case of MPS alone, one is presented with

200 missiles and the task of creating 4,600

simulators which resemble the missiles in all

observable respects. The simulator is created

de novor with no a priori constraints save to

match the MX. The LoADS Defense Unit, on

the other hand, is a functional object with

unique signatures, related to its operation,

which cannot be suppressed. It wouId therefore be virtually impossible to make the DU

match a set of missiles and simulators which

were not designed with the LoADS option in

mind. The three objects — MX, simulator, and

DU — must all be designed in concert.

PLU is therefore considerably more complex

for MPS defended by LoADS. It is too early to

tell whether deception can be arranged at all,

but it is probable that the 200 missile cannisters and 4,400 simulators would have to be

altered from ‘time to time as design and testing

proceeded to accommodate distinctive features of the DU. The later that a decision were

taken to give LoADS a place in the design of

the overall system, the riskier and more costly

the PLU process might become.

in addition to signatures, the operations by

which the MXS and DUS were shuffled periodicalIy among the shelters must not betray

the location of either. It appears that acceptable “movement algorithms” can be devised

to preserve PLU for both MX and DU simultaneously, whether the system were organized

into individual clusters of 23 shelters or into

larger “valIey clusters. ” it should be noted that

if rapid reshuffle were required to redress actual or suspected loss of PLU, extra time might

be required, depending on the availability of

transporters, to move the DU as well as the MX

missiI e.

There is some concern regarding a tactic for

attacking LoADS/MPS, called Shoot-LookShoot, whereby the Soviets could in principle

induce a breakdown of PLU. I f the Soviets

launched a first wave of attacking RVS which

caused the LoADS DUS to break out and expose their locations to remote Soviet sensors, a

second wave could be targeted on the basis of

known DU locations. They would then be able
Ch. 3—Ballistic Missile Defense 125

to destroy MX missiles at about the undefended price or even less. However, to sidestep

the defense in this way, the two waves of attacking RVS would have to be well-separated

in time. The Soviets wouId therefore have to

reckon with the possibility that the United

States wouId simply launch MX missiIes at the

Soviet Union between waves rather than await

the outcome of a subtle Soviet strategy. For

this and other reasons, reliance on Shoot-LookShoot would entail high risk to the Soviets, The

Soviets would presumably weigh these risks

against the simpler expedient of buiIding more

RVS and attacking the shelters directly

There are two scenarios for which a Soviet

Shoot-Look-Shoot capability could be intended. In the first (sometimes called “Spoof”)

scenario, an initial attack on LoADS/MPS is intended to cause the DUS to break out of their

shelters. A second wave of RVS is then targeted

on the basis of known DU locations. I n the second case, appropriate to long war scenarios, a

second attack is not necessarily planned at the

t i me of the first, but after an initial exchange in

which the DUS had broken out to perform their

defensive job, the Soviets could sense the locations of the exposed DUS. I n a subsequent exchange, the remaining U.S. force would be

left essentially undefended. Shoot-Look-Shoot

wouId in this case mean that the LoADS defense did not have the endurance that the MX

missiIes themselves wouId have.

Since deception is necessary for defense effectiveness, since the defense unit must break

out and expose itself to defend, and since the

Soviets would know that a shelter defended in

the initial attack must have contained an MX

missile, a Shoot-Look-Shoot strategy would

enable the Soviets to compensate for LoADS

with only a few hundred more RVS than they

wouId need to attack an undefended MPS, proprovided the U n i ted States did not Iaunch out between the first and second waves CaIcuIations

of the outcomes of various Shoot-Look-Shoot

scenarios, and a discussion of the problems

faced by the offense in mounting them and the

defense in countering them, are provided in

the Classified Annex.

Cost and Schedule

OTA has not performed independent cost

and schedule analysis for the LoADS/MPS

combination. The data presented in this section were supplied to OTA by the Army’s Ballistic Missile Defense Systems Command

(BMDSCOM). Comments that accompany

these data are those of OTA and do not necessarily reflect opinions of BMDSCOM.

The Army’s most recent (October 1980) cost

estimate to deploy a LoADS defense for the

4,600-shelter Air Force baseline MPS system

and operate it for 10 years is 8.6 bilIion constant fiscal year 1980 dollars. The $7.1 bilI ion

acquisition cost would include the costs of the

DUS, 200 separate transporters to move the

DUS, a modest amount of construction of

operating buildings in the deployment area,

and program development and management.

Operating costs are estimated at $153 million

per year. A detailed breakdown is presented in

table 20. These cost estimates do not include

the costs of potential modifications to the Air

Force baseline system in order to accommodate LoADS nor the cost of additional tactical warning and threat assessment systems

and command, control, and communications

(C) systems to support LoADS.

The present LoADS Program schedule is

funding- and Treaty-constrained, and precise

schedule information is classified. A schedule

Table 20.—Army’s LoADS Cost Estimate,

October 1980’

(constant fiscal year 1980 dollars in billions)

Research, development, testing, and

engineering . . . . . . . . . . . . . . . . . . . . . . 1.75

Defense units . . . . . . . . . . . . . . . . . . . . . 3.20

Transporters . . . . . . . . . . . . . . . . . . . . 1.13

Military construction . . . . . . . . . . . 0.16

System engineering and program

management . . . . . . . 0,54

Other investment . . . . . . . . . . . . . . . . . . 0.32

Acquisition cost . . . . . 7.10

Operations cost (10 years @ 0.15) . . . . . . . . . 1.53

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.63

a

From figures supplied by Army BMDSCOM

SOURCE Off Ice of Technology Assessment
126 ● MX Missile Basing

that assumes that the decision to remove constraints were not made until late in the decade

provides for final operating capability (FOC)

for the LoADS addition to MPS several years

after MPS FOC. This schedule would not require amendment of the ABM Treaty reached

at SALT I until later in the decade.

An accelerated schedule, assuming an early

decision and release from constraints, could

provide for LoADS deployment on about the

same schedule as MPS deployment. This would

require early amendment or abrogation of the

ABM Treaty and funding well above that now

projected for the LoADS Program.

Other Endo Concepts

Other endo BMD concepts besides LoADS

have been proposed and investigated. Dust

defense is technically feasible and very

capable but could have very low public appeal

as welI as a few potential technical drawbacks.

Terminal or low-altitude defenses based on

“simple” or “novel” concepts could be adequate as single-shot last-ditch defenses of

hardened targets against a small attack but

have not been proposed with the demanding

MX role in mind. The Army’s Site Defense represents the technology of the 1970’s and is inadequate for the MX role.

Dust Defense

Dust defense–also called environmental

defense – provides for burying “clean” nuclear

weapons in silo or MPS fields and exploding

them shortly before attacking RVS arrive. The

dust and debris lofted into the air would destroy approaching RVS either by direct collision with large earth fragments or by dust erosion of the RV’S heat shield. The detonations

would be placed so as not to damage the

ICBMS in their silos or shelters.

There are two possible ways of employing

dust defense. In the first, nuclear weapons

would be buried north of each silo or shelter

and exploded seconds before RV arrival. Small

radars placed north of each site would provide

the detonation signal. The RV would be destroyed in passage through the dense plume of

debris thrown up immediately by the explosion. The dust cloud which forms a little later

at higher altitudes would provide additional

protection for a longer period of time than the

debris stem, which falls back to Earth in a short

time.

In the second scheme, a smaller number of

weapons of higher yield would be exploded

throughout the fields several minutes before

Rv arrival, The heavy debris would thus have

fallen by the time the RV arrived, but by that

time the dust cloud would have formed. Since

the dust cloud from a high-yield weapon can

be tens of miles in width and breadth, many

siIos couId be protected by a single dust cloud.

Protection would last for approximately 20

minutes after which another set of weapons

would have to be detonated to provide continuing protection.

The weapons detonated would destroy far

more megatonnage than they constituted

themselves, a fact which makes the deliberate

detonation of nuclear weapons on U.S. territory somewhat more palatable from the

standpoint of fallout. But a more important

factor in reducing fallout is the possibility,

much discussed in the 1960’s at the time of the

PLOWSHARE Program studies of the peaceful

use of nuclear explosions, of constructing

nuclear weapons which produce very Iittle

residual radioactivity.

Conventional nuclear weapons give rise to

radioactive fallout in two ways. First, a certain

fraction of the weapon yield is produced by

fission. The fission products are unstable isotopes which give off harmful radiation when

they decay into more stable species. The rest

of the weapon yield is provided by fusion.

Large numbers of neutrons are formed in the

fusion process, and when these neutrons encouunter ordinary material in the vicinity of the

detonation, they transform it into radioactive

material.

Clean weapons reduce both sources of fallout. First, the clean weapon is constructed in

such a way that very Iitle of the yield is due to

fission, Second, one can surround the weapon

with material, such as berated water, which ab-
Ch. 3—Ballistic Missile Defense ● 127

sorbs the fusion neutrons readily without becoming radioactive Such a clean bomb is not

as compact as an ordinary nuclear weapon. It

might occupy the volume of a room. For that

reason, underground vauIts wouId be dug in

the silo fields to house the clean weapons. In

this way the radioactivity from the clean explosions could be reduced to about one one -

hundredth of the radioactivity from conventional nuclear weapons of equal yield

Though there is some uncertainty in the

composition of the stems and dust clouds

formed in nuclear explosions (which cannot be

entirely resolved within the Test Ban Treaty),

there is general agreement that dust defense is

an effective way to destroy attacking RVS

There appear to be no effective measures that

the Soviets could take to protect their RVS.

Moreover, large numbers of RVS could be destroyed within a short space of time i n this

way, a feat that is impossible for more conventional endo defenses

Potential drawbacks to dust defense, besides its perceived unpalatability, are the need

for warning, the need to provide multiple explosions if the attack occurs in waves wellspaced in time, and the fear of error

The cloud variety of dust defense requires

warning because the weapons must be detonated sever-a I minutes before attacking RVS arrive. I n principle, the stem variety does not require warning beyond that provided by its

radar, but it might be considered inadvisable

to keep the system activated at all times, since

a radar malfunction in peacetime might cause

inadvertent detonation Since warning is not

needed until late in the flight of the attacking

RVS in either case, it is easier from the technical point of view to provide an adequate system of this type than one which provides warning at the time of missile launch. This type of

warning is needed by alI endo defense systems.

An attack that came in waves could require

multiple detonations. If backup weapons were

buried to provide the capability for multiple

detonations, the weapons would have to be

spaced far enough apart that the first detonation did not destroy the remainder One U.S.

response to a muItiple-wave attack would simply be to launch in retaliation rather than

await the next wave, Offensive missiles can be

made that can launch through dust clouds

without damage. Dust defense could therefore

extend the timeline for launch under attack by

forcing the Soviets to attack in two waves. The

first wave would be destroyed by the dust, and

the second wave could not be launched until

the dust cloud had dispersed. The United

States would have this extra time to decide on

a reponse.

Error in the form of inadvertent or unauthorized detonation of the buried weapons

couId be avoided by the same set of procedures which prohibit launch of offensive missiles. The real possibility of error Iies in a false

warning message causing authorized detonation Fear of this type of error and procedures

to avoid it could lead to another type of error:

failure to authorize detonation when the warning information was correct, The problems

here are similar to those of a launch under

attack system.

Dust defense could therefore be by far the

most potent endo defense system. However, it

is seldom taken seriously because of concern

for public reaction.

Simple/Novel Systems

Simple/novel systems is a catch-all for a

wide variety of low-altitude or last-ditch

defenses of hardened targets. Examples go by

such names as Swarm jet, Porcupine, Gatling

Guns, SID CEP, Quickshot, SSICM, Bed of

Nails, and Agile, The interceptors consist of

rockets, shells, or inert projectiles with or

without nuclear warheads and guided by landbased radars or homing sensors. Not all are

simple, though many are novel indeed. LoADS

itself could be classed with these systems,

since it has a similar goal.

Because low-altitude defenses cannot guarantee muItiple intercepts over a single target in

rapid succession, they are inadequate to defend a small number of targets against a large

Soviet threat Indeed, most simple/novel systems were conceived as cheap and quickly de-
128 ● MX Missile Basing

ployable ways to increase the Minuteman attack price and create uncertainty for Soviet

targeters.

Some simple/novel systems might therefore

have capabilities similar to LoADS, though

none has been studied in the depth that LoADS

has A simple/novel system might therefore in

principle be capable of replacing LoADS in the

MPS basing role. This could come about either

by providing a last-ditch system simple and

cheap enough to deploy in association with

each of the 4,600 MPS shelters, or compact

enough to fit into a shelter deceptively I ike the

LoADS Defense Unit, However, none of the

concepts yet proposed combine confidence in

technical feasibiIty with low cost or smal I size

such that they would be attractive replacements for LoADS in the MPS role.

Because of the interest in simple/novel systems, two of the most promising examples are

discussed briefly below,

SWARM JET

The Swarm jet concept consists of radars deployed north of each defended site and a

launcher located near the site and containing

thousands of spin-stabilized, rocket-propelled

projectiles, When the radar detects an attacking RV, the launcher pivots in the direction of

the predicted intercept point and the projectiles launch into the threat tube in a swarm.

Each projectile weighs a few pounds and is designed to destroy an RV completely in a hypervelocity COII ision seconds before arrival at the

silo Swarm jet is designed to be constructed

from already-available or easily manufactured

components.

The object of the defense is to fill the sky in

the path of the attacking RV with enough projectiles to assure high probability of collision.

Though there is agreement among those who

have studied Swarm jet that collision with a

projectile will indeed destroy an RV, there is

disagreement about how may projectiles are

needed to assure a high collision probability.

This disagreement translates into uncertainty

in the size and cost of an effective Swarm jet

deployment. Factors that enter into the uncertainties are radar performance, the pointing

and aerodynamic properties of the projectiles,

and the effects of blast waves from precursor

or nearby nuclear detonations.

Like other low-altitude defenses, Swarm jet is

essentially a single-shot system and could

therefore claim with confidence only one RV

per silo from an attacker. The Swarm jet

launcher might be too large to fit into an MPS

shelter; if this were the case, the only way to

deploy it with MPS basing would be to provide

one Swarm jet unit for each shelter. This would

be costly but might deserve consideration if

deception proves too cliff icult for LoADS/MPS.

AGILE INTERCEPTOR

The idea of an Agile interceptor is to get

beyond the single-shot limitation of low-altitude systems by providing an interceptor so

maneuverable that it can intercept follow-on

RVS after detonation of a first despite poor

radar impact-point prediction due to firebal is

and despite being thrown off-course by blast

waves and winds, This program is i n the research stage.

The goal of the Agile interceptor is to intercept a few, but not many, RVS over a single

silo. Because its goal remains modest and because the technology is yet unproved, this concept is considered unsuitable for MX defense.

Site Defense

The Army’s Site Defense is a derivative of

the Sprint component of the Safeguard defense system of a decade ago. As a highaltitude endo system, it is susceptible to

blackout, penetration aids, and direct attack

on its few, large radars, as described in the

7-echn;ca/ Overview. Based on the technology

of the 1970’s, Site Defense is preserved as an

option in the event of a decision to field a

BMD system based on known technology in a

short period of time.

Though inadequate for the role of MX defense, Site Defense could be appropriate for

other BMD roles. For instance, it could be used

as a “threshold defense” for some important

U.S. assets such as warning sensors. In the con-
Ch. 3—Ballistic Missile Defense ● 129

cept of threshold defense, no pretense is made tempt to destroy the defended targets would

that the defense can ensure survival of the de- require such a Iarge attack as to constitute a

fended asset; its role is rather to increase the major provocation deserving of major U.S. reattack price to the point where a Soviet at- sponse.

EXOATMOSPH ERIC AND LAYERED DEFENSE

Technical Overview of Exo BMD

Exoatmospheric — “exe” — defense holds

high promise in theory because the long flight

times of RVS outside the atmosphere and the

large battlespace mean that many RVS targeted at the same site can be destroyed. In

contrast to low-altitude systems, systems with

an exo component could in theory defend a

small number of targets such as MX silos

against a large number of Soviet RVS, Additional strengths of exo BMD are the feasibility

of nonnuclear kill, the posslbility of mounting

multiple interceptors on a single booster

rocket, and the concept of adaptive preferential defense

Theoretical Advantages to Exo Operation

Nonnuclear kill is possible in space for several reasons First, the defensive sensors would

have a relatively long time–minutes, as opposed to seconds for an endo defense— to

track their targets, and the trajectories of

attacking RVS would be predictable because

they would be passing through empty space. It

would therefore be possible for the interceptor

to aim close enough to the RV that the large

destructive radius of a nuclear warhead would

not be necessary Deployment of barriers of

material in the paths of approaching RVS

wouId aIso be easier in the vacuum of space.

Nonnuclear kill is preferable to nuclear

methods because a nuclear defense’s own

warheads couId interfere with its sensors

(assuming the offense did not employ its own

nuclear precursors), nuclear warheads are

relatively expensive and heavy, and activation

of a nuclear defense would require procedures

for authorized nuclear release.

Interceptors boosted into space for exo defense could also carry many individual kill

vehicles — much as a MIRV’d missiIe carries

many RVS — resuIting i n some savings considering the cost of putting defensive vehicles into

space in the first place. Multiple warheads on

the same interceptor are impractical for use

with in the atmosphere, where the engagement

timelines are too short to make multiple deployments feasible.

Preferential defense is a tactic for multiplying the effectiveness of a defensive system if it

is only required to defend a subset of the targets under attack, For instance, suppose MX

missiles were deployed amongst the six Minuteman wings and that survival of the missiles

in two of these wings against a Soviet attack

was considered a sufficient goal for the defense. The defense could then concentrate its

exo interceptors upon destroying RVS targeted

at the two defended wings and abandon the

other four wings to the attacker. Which two

wings were chosen for heavy defense could be

kept secret from the Soviets or decided by the

defense at the last minute, In their targeting

planning, the Soviets would be unable to concentrate their RVS on the defended wings: they

would either have to do their targeting as

though all the wings were heavily defended or

grant the defense its goal of two surviving

wings. Adaptive preferential defense therefore

effectively multiplies the number of defensive

interceptors, In this example the Soviets would

behave as though all six wings were defended

as heavily as the two singled out by the United

States. Adaptive preferential defense is not an

effective tactic for endo systems because endo

interceptors must be located near to the targets they are defending. The presence of the
130 ● MX Missile Basing

defense near the defended sites therefore gives

the game away.

Infrared Sensing

An exo system that used large ground-based

radars to acquire targets outside of the atmosphere could be blinded by direct attack or

high-altitude blackout, and the view of groundbased optical sensors, which would be inadequate in any event, could be obscured by

clouds and dust. It is therefore desirable to put

the defensive sensors into space, either on the

interceptors themselves or on other space vehicles. Space-based radars would be heavy,

costly, and susceptible to jamming. For these

reasons, many exo concepts employ spaceborne passive infrared sensors, which are relatively light and compact, However, infrared

sensors are susceptible to offensive countermeasures such as decoys and other penetration aids.

Layered Defense

Like endo systems, exo defense alone would

be indequate to defend a small number of targets against a large number of attacking RVS.

In this case, the reason is not saturation of the

defense, but the cumulative effect of leakage.

It only takes one leaker to destroy a silo. If

many RVS were aimed at each silo, the odds

that one would get through could be high even

if the probability that each individual RV was

intercepted were high. The defense could attempt to stanch this hemorrhage of leakers by

attempting to intercept each RV more than

once (assuming that the multiple interceptor

vehicles targeted at the same RV would not interfere with one another). This tactic could be

effective but would drive the defense to enormous arsenals of interceptors.

If an endo defense were associated with

each silo, the combined exo/endo Layered

Defense would be more effective. The endo

system could catch leakers from the exo system and, moreover, the exo system would improve the performance of the endo system

since it would break up the concentrated,

structured attack patterns which saturate endo

systems. Thus, exo (Overlay) and endo (Underlay) defenses in a Layered combination have a

synergistic effect wherein the principal I imitation of each is alleviated by the presence of

the other. An endo defense could also help to

protect the launch sites for the Overlay interceptors from a disabling precursor attack. It

would also be difficult for an attacker to designl decoys to confuse both the Overlay sensors and the Underlay sensors. However, since

decoys are ineffective against low-altitude

radar sensing anyway, an attacker would probably concentrate his penetration aids against

the Overlay and not try to fool both layers.

Last, the tactic of adaptive preferential defense for the Overlay loses some of its attractiveness when there is an Underlay because the

Underlay cannot adapt: it can only defend the

area (or individual silo) near which it is deployed. If the defense concentrates its Overlay

resources on a subset of the silos and abandons the others to the attacker, then it leaves

the endo defenses associated with the abandoned silos open to easy saturation and penetration. These endo resources—all bought and

paid for— are wasted, whereas the whole purpose of adaptive preferential defense was to

make optimum use of defensive resources.

The Importance of overlay Ieakage

In contrast to low-altitude systems, which

can accept relatively high leakage and still do

a single-shot job, high performance is required

of the Overlay component of a Layered Defense. Thus one must take seriously the many

sources of leakage which can be present in the

complex process of exo interception and also

the possibility of having to face attacks involving decoys and other penetration aids, In practice, poor Overlay performance drives the defense to large inventories of interceptors in

order to maintain a given level of silo survival.

The effect of this sensitivity to Overlay Ieakage is best illustrated in the context of specific

calculations, Such calculations are presented

in the next section,
Ch. 3—Ballistic Missile Defense . 131

The Overlay and Layered Defense

of Silo-Based MX

Overlay Description

The Army’s concept of the exo component

of a Layered Defense — called simply the Overlay– is in the technology exploration stage. No

detailed system design is available as exists for

LoADS.

In outline (see fig, 62), the concept consists

of interceptors roughly the size of offensive

missiles equipped with infrared sensors and

carrying several kill vehicles (KVS), also

equipped with infrared sensors. The multiple

KVS would be mounted on the upper stage of

the interceptor. The interceptors, of which

there might be several hundred, would be

based in silos in the Central United States in

the same manner as offensive missiIes.

When attacking Soviet RVS were about twothirds of the way through their flight to U.S.

targets — about 10 minutes before impact — the

interceptors would launch into space, When

an interceptor reached space, its infrared sensor would scan its field of view and attempt to

discriminate approaching RVS from tank and

bus fragments and from decoys or other penetration aids. The infrared sensors would detect

these objects as warm spots —warm since they

were launched from the Earth — against the

cold background of space.

Each KV would be assigned a target determined to be a true RV and dispatched to intercept it. Using its own rocket power and infrared sensor, the KV would home in on the object and destroy it either by colliding with it

directly or by deploying a barrier of material in

its path, Since the closing velocity of RV and

Figure 62.—Overlay/Underlay Layered

Defense System

Warning sensor

Reentry vehicles,

Underlay /

/

Intticeptor

/ ““;” A ~ P

interceptor z z . “ 9 #

/- /1 1 f -i 3 /

\/- c

Interceptor 1

silo

fieids 8attie

manager

SOURCE Off Ice of Technology Assessment
132 ● MX Missile Basing

KV would be about 25,000 miles per hour, a

small fragment of material from the KV could

completely destroy the RV. Even a glancing

blow could damage the RV’S heat shield,

mean ing that it would either burn up or be carried off-course as it reentered the atmosphere.

System studies of the Overlay concept have

shown that performance would be improved

dramatically by providing an additional sensor

which would make an early assessment of the

size and nature of the attack, allowing interceptors to be assigned more efficiently to

regions of space. One idea for such a forward

acquisition system (FAS) would be rocketIaunched infrared sensing probes lofted into

space as soon as warning sensors indicated

Soviet launches. The probes would arrive on

station within a few minutes and remain there

for a short time before falling back to Earth.

During this time, they would relay information

on the trajectories of attacking RVS back to

the interceptor silo fields. Since at any one

time in the attack a number of probes would

be required to cover all the attack corridors

and their time on station would be limited, a

longer lived FAS system might be required as

well. This might consist of infrared sensors

mounted on high-flying aircraft maintained on

continuous alert and capable of several hours

of time on station. Alternatively, satellites

could perform an FAS function. However,

neither of these longer liived FAS systems

would be as capable as the probe.

The data acquired by the FAS would be integrated and interceptors assigned by a Central

Battle Manager or by Wing Battle Managers

associated with each set of defended silos. The

battle managers would decide on a defense

strategy and make interceptor assignments accordingly.

The battle managers and their data links

wouId have to be immune to disruption by precursor SLBM attack.

Last, an exo defensive system would require

early, secure, and reliable warning of Soviet attack. Systems to provide this warning must be

considered part of the Overlay architecture.

Risks to Overlay Effectiveness

The interceptors and kill vehicles, interceptor silos, FAS (probes, aircraft, or satellites),

battIe managers, and communications systems

described above wouId comprise an extremely

complex defensive system. The system architecture remains to be worked out in detail,

a n d m a n y technoIog y issues are yet u n resolved, 1 n the absence of a detailed system

design, it is not possible to analyze in quantitative detail the effectiveness and vulnerabilities of a Layered Defense system based

on the Overlay in the way that such analysis is

possible for LoADS. Analysis of the Overlay in

the context of MX basing must instead rely on

a qualitative estimation of technical risk and

the sensitivity of Overlay performance to factors which are yet unknown.

As in the discussion of LoADS effectiveness,

this section begins by asking how well the

Overlay must perform in order to guarantee

acceptable protection for silo-based MX missiles. Unlike a LoADS deployment with a single-shot goal, the effectiveness of a Layered

Defense based on the Overlay is very sensitive

to the details of system performance. One

must therefore take seriously the uncertainties

in overlay performance which exist at present.

These uncertainties concern both the fundamental technologies in the Overlay concept

and potential vulnerabilities in the working

system as a whole. For the moment, facing the

relative immaturity of the Overlay concept

and a near-term decision regarding MX basing,

it would be quite risky to rely on Layered Defense as the basis for ensuring MX survivable it y.

THE IMPORTANCE OF LEAKAGE

“The ability of a Layered Defense to protect

silo-based MX missiIes against a massive Soviet

attack depends sensitively on the performance

of the Overlay component. For LoADS/MPS,

by contrast, the defense would achieve a single-shot goal even if interception failed almost

as often as it succeeded.

The effectiveness of a Layered Defense is a

matter of probabilities, and the confidence of
Ch. 3—Ballistic Missile Defense ● 133

attacker and defender to acheive their goals

could depend not only upon the odds themselves but upon how willing either side would

be to “play the odds” in a nuclear war, The

discussion which follows is intended t. be

iIIustrative only: the precise numbers computed depend upon the assumptions and a

myriad of details, but the overall trends, indicating the sensitivity to Overlay performance, do not. The assumptions made here tend

to be rather favorable to the defense.

An illustrative silo basing arrangement for

MX might consist of 200 MX missiles deployed

in Minuteman I I I silos, The total U.S. ICBM

force would then consist of 450 Minuteman I Is

(one RV each), 350 Minuteman I I Is (three RVS

each), and 200 MX (10 RVS each, say), for a

total of 3,500 RVS in 1,000 silos. In what follows it is convenient to take each silo to be a

target of equal value, as though all missiles

were identical and carried between three and

four RVS. In actual fact, of course, the Soviets

would be Iikely to target, and the United States

to defend, MXS more heavily than Minuteman

IIIs and Minuteman 11 Is more heavily than

Minuteman I IS

Assume further that the Soviets deploy n o

penetration aids or alternatively that discrimnation is pertect. This assumpt ion concedes

quite a bit to the defense, as the section on

Decoys and Other Penetration Aids shows.

There is a certain probability that the Overlay will succeed in destroying an RV if it detects, tracks, and assigns a KV to it. Call this

probability the “efficiency” of the Overlay;

the leakage is one minus the efficiency. (It will

be necessary to assume that the probabilities

that individual intercepts succeed are statistically independent; this would not be true if,

e.g , the KVS concerned originated on the same

interceptor, ) A quite respectable value for the

efficiency in the absence of Soviet penetration

aids would be 0.85 (85 percent); this value

would assume achievement of al I of the Overlay “specifications “ A more modest value

would be 70 percent, and so percent would be

disappointing indeed. The point of this analysis is to show how strongly the number of U.S.

RVS surviving Soviet attack depends on Overlay efficiency.

The Underlay must also be specified. Here

many choices are possible, ranging from a

high-altitude Site Defense to simple single-shot

“terminal” defenses. Assume that associated

with each silo is a low-a It itude defense with the

capability to make a single intercept 70 percent of the time, a second intercept 50 percent

of the time, and no capabiIity to make three or

more intercepts above the same silo. This constitutes a rather large and costly deployment

and assumes effectiveness typical of lowaltitude systems. A second endo intercept is

allowed on the assumption that the second

leaker could follow the first with a time delay.

For the Soviet arsenal, targeted against both

MX and Minuteman, a range from 5,000 to

12,000 (reliable arriving) RVS could be considered; calculations wilI be done for a representative value of 8,000, Each arriving RV is

assumed to have a single-shot kilI probability

of one.

If the Soviets had 8,000 RVS and no reason

to target particular silos preferentially, they

could direct 8 RVS at each silo, timed to arrive

(if they penetrate the defense) within a short

time of one another. If the Overlay has an efficiency of 85 percent, then the probability that

all eight RVS aimed at a defended silo are

destroyed by the Overlay is 0.85 to the eighth

power or 0.27 (27 percent). The probability that

one RV penetrates is the probability that seven

RVS are intercepted (0.85 to the seventh power)

times the probability that one penetrates (0,1 5)

times the number of RVS (8) which have a

chance to penetrate, for a total probability of

0.38 (38 percent). (The apparently paradoxical

resuIt that one RV penetrates more often than

none refIects the fact that zero penetration

can only occur one way, whereas single penetration can occur eight different ways, ) The

probability that two RVS penetrate is 24 percent.

Thus, 27 percent of the time the silo is safe

because all RVS are destroyed in space. One

gets through 38 percent of the time, but the
134 ● MX Missile Basing

endo Underlay destroys this RV 70 percent of

the time. Two RVS get through 24 percent of

the time, but the first of these is destroyed T O

percent of the time and the second 50 percent

of the time. Thus the overall probability that

the silo survives is (0.27) + (0.7) (0.38) + (0.24)

(0.7)(0.5) = 0.62, or 62 percent.

How many silos would actually be defended

at all depends on the number of interceptors

the United States deployed. For instance, if the

United States deployed 400 interceptors with

10 KVS each, 500 silos could be defended

against the 8,000-RV Soviet attack. Since 62

percent of the defended silos would survive, a

total of 310 silos or 1,085 RVS would survive

the attack. The Soviets would have expended

8,000 RVS to claim 2,415 U.S. RVS, and over

4,000 Soviet RVS would have arrived on the

United States.

Suppose now that the Overlay efficiency

were not 85 percent, but only 65 percent. The

probabilities of none, one, or two RVS penetrating to the Underlay are then 3, 14, and 26

percent, respectively if the defense persists in

directing one KV at each RV. The result that

two RVS can penetrate more often than one

reflects the fact that there are more pairs of

RVS (28) than individual RVS (8). The higher

probabilities for multiple leakers means that

the endo defense has a harder job. In this case,

only 22 percent of defended U.S. silos survive.

If 4,000 KVS were used to defend 500 silos, the

total U.S. survivors would be 110 silos or 385

RVS.

But this would not in fact be the best U.S.

defense strategy if the Overlay efficiency were

low. A better result would be obtained by defending half as many silos with twice as many

KVS per silo, i.e., defending 250 silos and

directing two KVS against each Soviet RV. This

strategy would result in 70 percent survival of

the 250 defended silos, for a total of 175 silos

or 613 RVS surviving. The Soviets would again

have paid 8,000 RVS, and over 6,000 RVS would

have arrived on the United States. The Underlay defense at the 750 undefended silos would

have been saturated.

In this example, a 20 percent degradation in

Overlay efficiency (from 85 percent to 65 percent) results in the number of U.S. survivors

being reduced by almost one-half. This effect

demonstrates that the effectiveness of Layered

Defense to protect silo-based missiles depends

sensitively on the Overlay efficiency.

Figures 63 and 64 further demonstrate the

importance of Overlay efficiency. Figure 63

shows that the number of U.S. survivors decreases dramaticaIIy as the Overlay efficiency

degrades. Figure 64 shows that the size of the

defensive arsenal needed to assure survival of

1,000 RVS (286 silos) quickly gets out of hand if

the Overlay efficiency begins to slip. For a

fixed number of U.S. silos the sensitivity to

Overlay performance is more pronounced the

larger the Soviet threat. For a fixed threat, the

sensitivity is less pronounced the larger the

number of U.S. aim points.

TECHNOLOGY ISSUES

Because of the sensitivity to performance

described above, one must take seriously the

uncertainties which exist at this stage of the

Figure 63.—Sensitivity of Layered Defense

Performance to Overlay Leakage

(Soviet attack consists of 8,000 reentry vehicles)

(U.S. deploys 400 overlay interceptors)

900

-

800

 70 0 “

6 0 0 –

5 0 0 -

 40 0 —

3 0 0 -

200 –

100 —

o I 1 I I 1

O 10 20 30 40 50 60 70 80 90 100

Overlay efficiency

SOURCE: Off Ice of Technology Assessment
Ch. 3—Ballistlc Missile Defense ● 135

Figure 64.— U.S. Defensive Arsenal Needed to

Assure 1,000 Surviving U.S. Reentry Vehicles

(Soviet attack consists of 8,000 reentry vehicles)

10,000“

u

9,000 - 900 —

8,00 0 -

 80 0 —

7,000 - 700 —

 6,000 - 60 0 — al

 5,000 “ 50 0 —

 4,000 - 40 0 —

 3,000 “

 30 0 — o

 2,000 - 20 0 —

1,000 “

= 100 —

o - 0

O 10 20 30 40 50 60 70 80 90 100

Overlay efficiency

SOURCE Office of Technology Assessment

Overlay’s development. Many aspects of the

Overlay interception function require the frontier technologies of infrared sensor design,

compact computer design, rapid computer

throughput, software architecture, small homing and KV technology, and so on. The system

requirements are demanding, and at al I stages

of the interception process advances must be

made to meet them. Furthermore the stages

are interlinked in such a way that failure at one

stage could cause failures at others and degrade overalI system performance significantly, There is no reason to believe that,

given time and money, the uncertainties in

Overlay technology could not be reduced to a

point where a clearer estimation of the value

of an Overlay system for the protection of silobased missiles could be made Nor is there any

particular reason —with one exception, discussed in the section Decoys and Other

Penetration Aids – to believe that fundamental

technical problems will be encountered which

by themselves would constitute “Achilles’

heels” for an Overlay defense. Indeed, there is

some reason for optimism, since the needed

technology elements fall into categories—

compact data processing, infrared sensing,

miniature guidance systems, homing, etc. — in

which rapid progress is occurring now and

more is expected in the future. Rather, the risk

lies in the cumulative effects of shortcomings

in the performance of technology elements at

many stages of the interception process. In

many cases the capabilities of today’s technology falls short of the requirements of the

Overlay by wide margins. Though progress can

and should be expected, even small shortcomings couId uItimately prove significant, since

poor performance in one area can induce

failure elsewhere, and the cumulative effect

could be to reduce total system performance

below the high standard required for MX defense. Technology forecasting is always risky,

and in the case of the Overlay one is simply

faced today with an unknown quantity.

Though the level of confidence in Overlay

technology may in time increase to the point

where it could support a decision regarding

MX basing, at the moment it appears quite

risky to depend on successful resolution of all

outstanding issues. The following discussion

seeks to highlight unresolved technology

issues and convey a sense of the complexity of

exo defense.

The interception process begins when the

probes or other FAS vehicles survey the attacking “threat complexes, ” the clusters of RVS,

bus and tank fragments, and possibly decoys

or other penetration aids, which are boosted

into space by Soviet offensive missiles. I n a

large Soviet attack there would be tens of

thousands of such objects in the sky. Each

probe sensor should have as wide a field of

view as possible so that a small number of

them can survey the whole sky. But a wide

field of view means either a large sensor, which

is hard to protect from interfering background

from the Sun, Earth, atmosphere, and other effects; or a slow scanning rate, which makes it

difficuIt for the sensor to correlate what it sees

on one scan with what it saw on previous

scans, essential for discriminating RVS from

other objects and for compiling accurate trajectory information. Unlike radars, infrared

sensors cannot determine the ranges of distant

objects but only their angular positions in the

sky. Range must be inferred from changes in

the angular positions of objects with time.

Angular position must therefore be measured
136 ● MX Missile Basing

very accurately, requiring precise orientation

of the sensors in space. The threat complexes

might also be rather dense: a single spot in the

sky could later resolve itself into several objects. The probes must resolve all objects and

observe them long enough to attempt to discriminate RVS from nonlethal objects and

compute accurate trajectories. If all this is

done poorly or too late, too many interceptors

will be allocated to some regions of space and

not enough to others.

The probes must then “handover” their files

of objects to the interceptors, telling the interceptor sensors where to find each object

and what it looks like. The interceptors must

reacquire each object in their respective sectors, attempt discrimination again, and determine how best to release their KVS. Again,

poor performance at this stage degrades performance at the next,

Last, the interceptor sensors must hand over

targets to individual KVS. The KVS must then

maneuver in such a way that they come within

lethal range of an RV approaching at 25,000

mph The KVS must also be able to distinguish

the true RV from objects placed nearby. If the

first intercept failed, a second wave of interceptors wouId have a very short time to perform all the required functions. It is not clear

in any event that it would be possible to tell

which intercepts had failed on the first attempt.

The infrared sensors are the most delicate

element of the Overlay system. Infrared sensors can be disrupted by heat, nuclear radiation, and rocket exhaust gases. They would

have to be mounted on very sensitive gimbal

systems with accurate inertial guidance, lnfrared sensors measure the temperature characteristics of approaching objects. These characteristics depend sensitively upon the position of the object relative to the Sun and Earth

and on the time of day, season, and weather

conditions on the Earth below. All of this data

would have to be made available to the sensors before they could interpret what they saw.

Infrared sensors of great sensitivity are also

rather temperamental in that each behaves dif -

ferently and must be calibrated separately,

and a given i I I urn i nation of the same sensor

can sometimes result in different output voltages. These latter factors introduce some fundamental limitations in temperature resolution, an important factor in discrimination.

SYSTEM ISSUES

In addition to the risk introduced by the high

technology required, the Overlay as a system

could have vulnerabilities much Iike the

vulnerabilities of other basing modes. For instance, the Overlay would depend on tactical

warning, since the system must begin to function early in the flight of Soviet ICBMS. The

Overlay could thus share some of the potential

vulnerabilities of other basing systems which

depend on warning such as launch under

attack and air mobiIe MX. The battle management function requires survival of the command centers and of secure, high-data-rate

communications among the FAS, battle managers, and interceptor silo fields. The concerns

here are similar to those regarding wartime survival of our national military C systems. Also,

as with LoADS, attention must be given to offensive tactics designed to confuse or bypass

the defense.

Limitations of the Overlay defense against

submarine-launched balIistic missiles (SLBMS),

which couId attack the Overlay’s own components, are discussed in the Classified Annex.

Leakers from a precursor ICBM attack might

also threaten critical system elements.

In the absence of a specific system design, it

is again not possible to estimate vuInerabilities

precisely. The interceptor silos and especially

the probe silos would be few in number. Present Soviet SLBMS have limited silo-killing

capability, and they are not normally deployed

in large numbers near U.S. shores. Still, the

Overlay defense assets would be high-value

targets for an SLBM precursor attack, and depending on their hardness they could be vulnerable. Some thought has been given to providing an endo defense for the Overlay missiles themselves. Softer targets such as

possible ground-based battle management
Ch. 3—Ballistic Missile Defense ● 137

bunkers and their communications links could

be vulnerable to less accurate SLBMS.

If strip-alert aircraft were used to supplement the probes or to serve as battle management centers, they would have the same vulnerabilities as the bomber force and Air

Mobile MX. One must also consider an antisatelIite threat if satellites were used to aid an

FAS,

Care must also be taken to provide for survival of the high-data-rate communications

linking FAS, battle managers, and interceptor

fields, The generic technical problems of providing survivabiIity for communications are

similar to the case of launch under attack and

to the C systems of other basing modes.

A complex defensive system like the Overlay must also reckon with offensive countermeasures. The most important of these is the

use of penetration aids, discussed in the next

section. Other tactics are discussed i n the Classified Annex,

Detailed study of vulnerabilities at the total

system level must wait until the Overlay concept is translated into a working design. Experience with the national military C’ system

and studies of launch under attack, air mobile

MX, LoADS/MPS, and other basing systems

give an idea of the scope of problems which

can be encountered when a complex MX

basing system faces a future Soviet threat. For

the moment, the uncertainties in whether a

robust wartime system can be fashioned from

the Overlay concept are another source of risk

to a decision to make Layered Defense the

basis for MX survivability.

Decoys and Other Penetration Aids

The Overlay concept is based on the practicality of infrared sensing in space. However,

infrared sensing is potentially critically vulnerable to offensive countermeasures in the

form of decoys and other penetration aids.

Unlike the LoADS radar operating at low altitudes, which could measure the weight of approaching objects, the Overlay infrared sensors would measure their temperature characteristics. Decoys able to fool the LoADS radar

83-477 0- -81-1 0

must be heavy, and adding heavy decoys to an

offensive missile requires removing RVS, since

the missile has Iimited throwweight. Measuring

weight is therefore a strategically significant

method of discriminating true RVS from decoys, since the offense would presumably not

choose to offload RVS and replace them with

equalIy heavy decoys. On the contrary, there is

no impediment in principle to deploying lighweight decoys which have temperature characteristics indistinguishable from those of true

RVS. Temperature, which is fundamental to

the Overlay sensing method, is not a strategically significant discriminant. The offense

might therefore be able to deploy a Iarge number of excellent lightweight decoys on its

offensive missiles without having to offload

many RVS. This would call into question the

effectiveness of an exoatmospheric defense of

MX.

This section will indicate some of the elementary physical principles that permit the design of Iightweight penetration aids. It wilI also

indicate the practical difficulties which the offense would face in mounting decoyed attacks

as welI as those the defense wouId face in

countering them. A more complete discussion

is relegated to the Classified Annex.

To get a feeling for the importance of discrimination, consider the case if the offense

provided along with each RV a sing/e perfect

decoy. A KV approaching the two objects

would then intercept the true RV 50 percent of

the time. If the efficiency of the defense, as

defined in the last section, were 85 percent in

the absence of decoys, and if one KV were dispatched against each RV/decoy pair, then the

true RV would be intercepted only (0.85) (0.5)

= 43 percent of the time. This low efficiency

(high leakage) would be catastrophic to the

defense, as figures 63 and 64 in the previous

section show. If on the other hand the defense

directed a KV at both the RV and the decoy,

then the same number of U.S. silos would survive as in the no-decoy case, but an arsenal of

defensive missiles twice as numerous would be

required to produce this resuIt

In practice, no decoy is perfect, and on the

other hand the offense could deploy many
138 ● MX Missile Basing

more than one decoy with each RV. In practice

also, a tradeoff is made between leakage (intercepting the object judged most likely to be

an RV and allowing an RV to penetrate if the

guess is wrong) and wastage (intercepting

everything). In the case of the Overlay, the

need to keep leakage low means that the best

solution for the defense is usually to accept

high wastage. Thus, an offensive decoy deployment would tend to drive the defense to larger

numbers of defensive interceptors — in the example above, applied to the model in the last

section, twice as many, or almost as many defensive missiles as offensive missiles.

INFRARED SENSING AND TEMPERATURE

A metal bar heated to very high temperatures glows white-hot. If its temperature is

lowered somewhat, it glows red-hot. if cooled

further—to room temperature— it no longer

glows in the visible part of the spectrum but at

longer wavelengths, in the infrared part of the

spectrum. A room-temperature object thus

“glows infrared” and can be “seen” by a detector sensitive to infrared light.

An RV launched into space from the approximately room temperature condition of its silo

forms a glowing spot against the dark (i.e.,

cold) background of space. Infrared sensors

can measure both the color (i. e., the precise

shade of infrared light) and the brightness of

the RV and of any other objects, such as decoys, which accompany it. The color of the object reveals its temperature and its brightness

reveals its size and the type of material it is

made of. Decoy/RV combinations that appear

to the infrared sensors to have identical color

and brightness cannot be discriminated.

In addition to the warmth it brings with it

from the Earth, the object absorbs energy from

the Sun above and the Earth below and loses

energy to cold space. Its color could therefore

change as it were warmed or cooled. In addition to emitting light because of its temperature, the object also reflects infrared

radiation from the Earth. An infrared sensor

therefore senses the combination or sum of the

emitted and refIected energy from the object.

T here is a relationship between the tendency

of a body to emit thermal radiation because of

its temperature and its tendency to reflect

radiation which shines on it. For a body of a

given size (more precisely, surface area) at a

given temperature, the sum of its effectiveness

in emitting radiation of a given wavelength

and in reflecting it is the same no matter what

the body is made of. Therefore, the less infrared radiation a body in space emits, the

more it reflects from the warm Earth and vice

versa. The relative emittance and refIectance

does depend on the nature of the body, but

only on what the surface of the body is made

of and not what is inside it.

Using only these elementary principles of

physics, it is a straightforward matter to design

RV/ light-decoy pairs which appear identical to

infrared sensors. A wide variety of other examples of penetration aids based on simple

thermal properties of materials can also be

designed. These are discussed at some length

in the Classified Annex.

MEASURE AND COUNTERMEASURE

In practice, the situation is more complex

than simple physical principles alone would indicate, with many constraints and opportunities both for the offense and the defense.

Despite these complexities, the fact remains

that there is no principle and no detector that

couId guarantee perfect Overlay discrimination. The burden would thus rest with the defense to maintain its confidence that its

methods of discrimination were adequate to

meet a decoy threat.

l-o begin with, there would be practical constraints on the offense. Foremost among these

is the fact that the best results would be obtained by altering the RV to make it easier for

a Iight decoy to match. Though these changes

are minor, inexpensive, and need not affect RV

performance in the least, there could be some

psychological reluctance to tamper with the

lethal RV for the sake of a nonlethal decoy. It

is also one thing to design the perfect decoy

ancl quite another to package it, mount it on

an ICBM, and deploy it in space so that its
Ch, 3—Balllstic Missile Defense ● 139

deployment process and in-flight motions (assuming these could be observed by the defense

in an attack) resemble those of a true RV.

Constraints on the defense include the fact

that infrared sensors are not perfect (i. e.,

cannot determine brightness and temperature

precisely, especially in the presence of background) and they would not have a very long

time to observe objects in an engagement. The

temperature characteristics of objects in space

furthermore depend on the position of the Sun

and Earth relative to the sensor and the time of

day and weather conditions on the Earth below. Overall, the interception process is difficult enough even in the absence of decoys, as

discussed in the last section.

Since there is no fundamental principle on

which infrared sensors can rely to guarantee

discrimination, there could be value in some

advance knowledge of the type of penetration

aids the offense deployed. It is possible (likely

is too strong a word) that by observing flight

tests, the defense could Iearn enough about

the offense’s penetration aids to devise a discrimination scheme based on some distinctive

feature or detail of the offense’s design or

deployment procedure. However, since there

appears to be a wide variety of effective penetration aids which the offense could use, this

approach based upon particulars rather than

principles could succeed for one penetration

aid but faiI for another.

Details and further discussion of penetration aids, constraints, and tactics can be found

in the Classified Annex.

Overlay discrimination is a difficult problem, the practical details of which are not understood, though the principles are. Testing of

penetration aids designed expressly and exclusively for the purpose of Overlay penetration is required before it can be known whether the perfect decoy of principle can be realized in practice and whether less-than-perfect

decoys still make defense based on infrared

sensing too difficult and costly to undertake.

For the moment, the very fact that effective

decoys are possible counsels caution.

HISTORY OF BMD AND THE ABM TREATY

The development of ABM systems by the

United States in the early 1950’s followed the

decision to begin development of ICBMS.

During the mid-1 960’s, the johnson administration proposed the deployment of the so-called

Sentinel ABM system to provide both area and

point defense against a limited nuclear attack.

This proposed ABM system was reviewed in

1969 by the Nixon administration which opted

instead for an ABM system to defend Minuteman siIos. Deployment of the Nixon administration’s Safeguard ABM system was begun in

the early 1970’s but was brought to a halt

following negotiation and ratification of the

ABM Limitation Treaty of 1972. The Treaty

was subsequently amended by the Protocol of

1974.

With the development of ballistic missile

defense, doubts about the long-term viability

of international security based on a “balance

of terror” began to mount WhiIe alternatives

to maintaining a balance of terror were explored through a variety of formal and informal channels, by the mid-1960’s it seemed

to many senior U.S. policy makers that some

sort of arms Iimitation on balIistic missile

defenses would be preferable to either an ABM

arms race or a major revision in the post-World

War I I “balance of terror”.

For example, Defense Secretary Robert S.

McNamara noted:

Should they elect to do so, we have both the

Ieadtime and technology available to so increase both the quality and quantity of our offensive strategic forces –with particular attention to highly reliable penetration aids—that

their expensive defensive efforts wilI give

them no edge in the nuclear balance whatever.

But we would prefer not to have to do that.

For it is a profitless waste of resources, pro-
140 ● MX Missile Basing

vialed we and the Soviet can come to a

real istic strategic arms-limitation agreement.

Even though Secretary McNamara had serious reservations about ABM systems in general, he nevertheless proposed to deploy an

ABM system to defend the United States

against some nuclear attacks. The Sentinel

ABM system proposed by the johnson administration included a long-range, high-altitude

exoatmospheric interceptor missile, the Spartan, guided to targets by a very large radar and

a smaller, shorter range interceptor missile,

called Sprint, also guided to its targets by

radar. Both missiles were armed with nuclear

warheads which destroyed incoming reentry

vehicles. The original johnson administration

proposal envisioned deployment of the Sentinel ABM System at some 14 sites including

ICBM silo fields in Montana and North Dakota

as well as several major cities.

The Nixon administration reviewed the proposed Sentinel ABM system in light of both

U.S. strategic requirements and the intense

political opposition that arose over the potential deployment of nuclear weapons adjacent

to American cities and concluded that the use

of Sentinel radar and interceptor components

to defend U.S. Minuteman fields would be an

appropriate and strategicalIy significant response to the Soviet deployment of an ABM

system around Moscow. On March 14, 1969,

President Nixon announced his plan to deploy

an ABM system to defend ICBM silos in Montana and North Dakota:

This measured deployment is designed to

fulfilI three objectives:

1. Protection of our land-based retaliatory

forces against a direct attack by the

Soviet Union

2. Defense of the American people against

the kind of nuclear attack which Communist China is likely to be able to mount

within the decade,
Ch. 3—Balistic Missile Defense ● 141

In general, the ABM Limitation Treaty of

1972, as amended by a Protocol negotiated in

1974, prohibits ABM systems based on the

technology deployed by the United States and

the Soviet Union in the late 1960’s and early

1970’s, The Treaty as amended does permit

each side to deploy one ABM system for defense of either its national capital or an ICBM

silo field. The Treaty also permits continued

research and development on allowed ABM

systems, bans other types of ABM development, test, and deployment, and provides for

further negotiations on specific limitations of

new ABM systems based on technologies not

deployed in the 1970’s

Article I of the Treaty) prohibits ABM system deployments other than those specifically

permitted by subsequent articles of the Treaty.

Article I I defines ABM system components. Article I I 1, paragraph (b), permits the United

States to deploy one ABM system with the following characteristics:

● not more than two Iarge phased-array ABM

radars,

● not more than 18 smalI phased-array ABM

radars,

● not more than 100 ABM interceptor Iaunchers and not more than 100 ABM interceptor

misslIes i n a deployment area having a

radius of less than 150 kilometers centered

on the middle of an ICBM silo field.

Article IV of the ABM Limitation Treaty perm its development and testing of ABM components at designated test ranges without

counting such components in the quantitative

limits established in article I I 1,

Article V of the Treaty bans the development, test, or deployment of sea-based, airbased, space-based, or land-mobile ABM systems or components. Article V also bans the

development, test, or deployment of ABM

interceptor launchers which contain more than

one interceptor or which are capable of automatic or semiautomatic interceptor reload.

Other official statements incorporated into

the legal restrictions of the ABM Limitation

Treaty also affect future ABM system development, test, and deployment. Agreed statement

(D) contains the following provision:

In order to insure fulfillment of the obligation not to deploy ABM systems and their

components except as provided in Article I I I

of the Treaty, the Parties agree that in the

event ABM systems based on other physical

principles and including components capable

of substituting for ABM interceptor missiles,

ABM launchers, or ABM radars are created in

the future, specific limitations on such

systems and their components would be subject to discussion in accordance with Article

Xl I I and agreement in accordance with Article

XIV of the Treaty. ’

Agreed statement (E) prohibits deployment of

ABM interceptor missiles with more than one

independently guided warhead.

The ABM Limitation Treaty Protocol negotiated in 1974 and ratified in 1976 further

amended the ABM Limitation Treaty in the following respects. Article III of the Treaty

original Iy permitted both the United States

and the Soviet Union to deploy two ABM systems in two deployment areas. One permitted

system could defend an ICBM silo field;

another could defend the national capital. Article I of the 1974 Protocol limits each side to

only one ABM system deployment.

Article I I of the Protocol permits each side

to shift deployment of its permitted ABM system once. In the case of the United States, the

protocol would permit the dismantling and

destruction of the ICBM silo ABM defense system at Grand Forks and the relocation of the

ABM system to the Washington, D.C. area.

Application of ABM Treaty Provisions

to MX Defense

ABM systems deployed to defend MX are

limited by the ABM l-imitation Treaty of 1972

(as amended by the 1974 Protocol) in two distinct ways. First there are limitations on the

deployment of ABM systems. Second, there

‘I bid, p 143
142 ● MX Missile Basing

are limitations on the development of new

ABM systems.

ABM deployments are limited by the ABM

Treaty as amended in the following respects:

1

2

3.

4

5.

6,

7.

any U.S. ABM system may only be deployed in a circle of 150-km radius

centered on the Grand Forks, N. Dak.,

ICBM field;

LoADS defense units could not be deployed if any system component were explicitly not of a fixed type;

since each LoADS unit would contain one

small radar, no more than 18 LoADS DUS

could be deployed under terms of the

radar limitations of the ABM Treaty;

the total number of LoADS or Overlay

ABM interceptor launchers and ABM

interceptor missiIes couId not exceed 100;

LoADS defense units could not be deployed if each unit contained more than

one ABM interceptor launcher. Alternatively, even if each LoADS defense unit

contained only one interceptor launcher,

it would stilI possess in principle automatic, semiautomatic, or rapid reload

capability, barred by the Treaty;

since each Overlay KV is an independently guided warhead within the meaning

of the Treaty, deployment of more than

one such warhead on each Overlay interceptor missile would be prohibited

under provisions of agreed statement (E).

deployment of space-based laser ABM

systems is explicitly prohibited by article

V of the ABM Treaty,

The development of future ABM systems is

also limited under terms of the ABM Limitation Treaty. The United States and the Soviet

Union have defined development of ABMs for

purposes of the Treaty as follows:

The obligation not to develop such systems,

devices or warheads only to that stage of development which follows laboratory development and testing, The prohibitions on development contained in the ABM Treaty would start

at that part of the development process where

field testing is initiated on either a prototype

or bread-board model. 5

Thus, the following limitations would apply to

the development of specific ABM systems

such as LoADS, Overlay, or even space-based

ABM systems:

1.

2.

3.

mobile components of ABM systems

developed beyond the laboratory such as

LoADS defense units would be banned;

multiple independently guided KVS for

the Overlay could not be tested beyond

the confines a laboratory;

development of unique components for

spaced-based laser ABM systems would

be banned.

Future ABM Limitation Negotiations

The ABM Treaty provides that either side

may propose amendments during semiannual

meetings or special meetings of the Standing

consultative Commission which was established to resolve questions of interpretation in

the Treaty as well as to supervise and resolve

questions of verification. The 1974 Protocol

amending the Treaty arose out of just such

Standing Consultative Commission discussions. The Treaty, which is of unIimited durat ion, also provides for a formal review conference every 5 years at which time either side

may propose changes or amendments. The

next ABM Limitation Treaty Review Conference is scheduled for October 1982.

Present ABM options for the defense of MX

deployments are significantly constrained by

the Treaty from the standpoint of final engineering. Substantial research on new ABM

systems can be undertaken, and development

and testing of ABM components whose purpose is to modernize the mothballed Safeguard system can also be undertaken, New

radars, new interceptors, and new warheads

“ Ball Istlc MI$SIIP Defense, ” In U S Congress, House Committee on Foreign Affalr$ and Senate Committee on Foreign Relat Ion 5, 4 rrrs C-on tro/ /mpa c t Statement J tor f I >ca / Year / 982

(Washington, D C U S (government Printing Office, 1981, p

195
Ch. 3—Ballistic Missile Defense ● 143

for Safeguard are all testable and deployable

under terms of article VI I of the Treaty permitting modernization of existing ABM systems,

Even development of directed energy weapons

for possible use as ground-based ABM systems

would be permitted under terms of the Treaty,

so long as deployment as modernization for

the Safeguard system was envisioned.

The United States might wish to explore the

possibility of further amending the ABM Limitations Treaty in a manner that would permit

engineering development and possible deployment of the LoADS or Overlay ABM system as they are presently envisioned during the

course of the 1982 ABM Limitation Treaty Review Conference. Reopening discussions of the

substantive provisions of the ABM Limitation

Treaty does, however, raise serious questions

in need of further analysis beyond the scope of

the study.

The process of renegotiating the ABM Limitation Treaty is subject to uncertainty. The

Soviets, too, have an active ABM research and

development program which is also constrained by the ABM Limitation Treaty. Modifications in the terms of the ABM Limitation

Treaty which would permit the United States

to proceed with development and testing necessary to advance the LoADS ABM technology

into engineering and full-scale engineering development, or permit development of Overlay

technology, would also permit comparable

developments in the Soviet ABM program.

Hence judgments of the technical, political,

and military benefits to be gained by reopening negotiations on ABM I imitations will have

to be made should some basing mode for the

MX missile requiring ABM systems be contemplated.
Chapter4

LAUNCH UNDER ATTACK
Chapter 4.-LAUNCH UNDER ATTACK

Page

Overview of Rationale for LUA and Possible Drawbacks . ..................147

Possibilities for LUA Systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148

Targets and Military Utility . . . . . . . . . . . . . . . . . . . . . .................149

Timelines. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..........150

Overview ofTechnical Requirements . . . . . . . . . . . . . . . . . . . . . .........150

Early Warning and Attack Assessment Systems. . . ....................151

Command Posts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...............154

Communications Links. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..........154

Pindown. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ........156

Procedures. . . . . . . . . ~. . . . . . . . . . . . . . . . . . . . . . ...................156

Operational Possibilitiesfor LUA . . . . . . . . . . . . . . . . . . . . . . ; . . . . . . . . . .. ...159

Illustrative Soviet ICBMAttackson U.S. Silos Only. . . . . . . . ............159

Illustrative Soviet ICBM/SLBM Attackon U.S. Silos and LUACapability

ExcludingWashington. . . . . . . . . . . . . . . . . . . . . . . .................160

illustrative SovietlCBM/SLBM Attack on U.S. Siios, OtherMilitary

Targets, LUACapability, andWashington. . .......................161

Attemptto Disrupt U.S. Technical Capabilityto LUA Precedes Soviet

Attack . . . . . . . . . . . . . . . . . . . . . . . . . . ..........................161

SummaryofCritical lssuesfor LEA. . . . . . . . . . ..........................162

information Availableto Decisionmakers. . . . . . . . . . . . . . . . . . . . . .. ....163

Decision Timelines. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..163

Possibilities forDiplomatic and OtherActivities. . ....................163

Providingfor Launch Authority . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. ...163

Fear That U.S. LUACapability Could Somehow BeSidestepped . .........164

RiskofError. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. ...164

LISTOF FIGURES

Figure No. Page

65. AttackTimeline. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ................150

66. Launch-Under-Attack System Architecture . . . . . . . . . . . . . . . . . . . . . ......151
Chapter 4

LAUNCH UNDER ATTACK

Another approach to MX survivability is to

accept vulnerable silo basing and resolve to

launch silo-based MX missiles before attacking

Soviet reentry vehicles (RVS) could arrive to

destroy them. This type of response to a Soviet

attack is called launch under attack (LUA)

Adopting this approach to MX survivability

would imply relying on LUA as opposed merely

to preserving it as a possibility The United

States now preserves the capability to LUA as a

matter of stated doctrine, Some, though not

all, of the other basing modes described in this

report would also allow this capability to be

preserved. This chapter does not in any way

address the present U. S doctrine or the status

of means to support that capability, but only

potential future systems of reliance on LUA.

OVERVIEW OF RATIONALE FOR LUA AND

POSSIBLE DRAWBACKS

The chief attraction of LUA basing is that it

can be implemented faster and more cheaply

than other basing modes since there is no basing “mode” to speak of. The United States

could in principle put MX missiles in the

Minuteman silos as they came off the assembly line, meaning MX deployment in the second half of this decade However, some of the

hardware needed to support the LUA capability (warning sens.ors, communications links,

and the Iike) might have longer lead-times. A

truIy robust and dependable system might

therefore take SIightIy longer to deploy.

Even with a wide range of sophisticated,

redundant support hardware–just about

everything one could think of buying in the

way of sensors and communications— the

price of an LUA system (excluding the missiles

themselves) would come to billions of dollars

rather than tens of bilIions as for other basing

modes. Some of the systems required for LUA

would in fact be desirable, perhaps even

necessary, to deploy with any basing mode.

This hardware– warning sensors, command

posts, and communications links–could be

made virtually impossible for the Soviets to

destroy or disrupt. What cannot be assured

with confidence is that competent National

Command Authorities (NCA) would in all circumstances have access to this system in the

short LUA timeline; this is essentialIy a matter

of procedures and national policy, not technology.

Because already-existing silos (or a small

number of new ones) couId be used, there

would be Iittle new construction and hence

little environmental and societal impact.

LUA would preserve familiar features of silo

basing, including weapon effectiveness as

measured by accuracy, time-on-target control,

and the Iike; famiIiar force management procedures; and familiar arms control verification

procedures.

From the point of view of strictly military

utility, the possibilities for an LUA force differ

very little from those available to a survivable

force, The same targets (and perhaps more)

would be available in the first few minutes of a

war as in the first few hours or days. Essentially

the same targeting flexibility could be provided with technicaIIy feasible hardware.

Reliance on LUA also has potentially serious

drawbacks.

Depending on the circumstances, decisionmakers could lack crucial information regarding the extent and intent of the Soviet attack —

information necessary to gauge the proper response It is not clear, however, that much better information would always be available to

the commander of a survivable force within a

short period after a n uc I ear attack

147
148 ● MX Missile Basing

Decisionmakers would also lack an interval

between attack and response during which

intelligence information could be assessed,

diplomatic measures considered, and the intent of the U.S. response signaled — assuming

the circumstances of nuclear war permitted

such things at al 1.

Decision time would obviously be very

short. NCA would have to make unprecedentedly weighty decisions in less than 15

m i nut es.

To guarantee the LUA capability against

some contingencies it might be necessary to

adopt unpalatable procedures regarding, for

instance, delegation of launch authority.

No matter how much money and ingenuity

were devoted to designin g safeguards for the

U.S. capability to launch under attack, and

even if the safeguards were very robust indeed,

it would probably never be possible to eradicate a Iingering fear that the Soviets might

find a way to sidestep them.

Finally, despite all safeguards, there would

always remain the possibiIity of error, either

that missiles were launched when there was no

attack or that they failed to launch when the

attack was genuine.

POSSIBILITIES FOR LUA SYSTEMS

There is a wide variety of possibilities for

LUA systems, and which is “best” is not really

a matter of technology but of doctrine, procedures, and national policy. Doctrine determines the types of attack which the system is

designed to meet and those which it is not, For

instance, it wouId be easier to configure an

LUA system on the assumption that a Soviet attack would be directed at missile silos and

perhaps other military targets but would not

be preceded by attack on Washington, If

Washington were attacked first, an LUA system designed on this assumption might fail.

But since the intercontinental ballistic missile

(ICBM) vulnerability problem is perceived generalIy within the context of counterforce attacks excluding U.S. cities, it is not clear that

an LUA force must be required to meet such a

contingency; in this case it might be thought

that an appropriate response could be executed with surviving submarine, cruise m issile, and bomber forces. These are clearly

issues of doctrine. Regarding procedures— and

to take a more extreme example— it would

also be easier to design an LUA system on the

assumption that launch authority were vested

in certain circumstances in persons other than

the President and other duly constituted NCA

or even that the response to be made to a

Soviet attack of a given sort were decided in

advance and, so to speak, “wired into” the

ICBM system.

Doctrine and procedures — issues of national policy, not technology— more than anything else therefore determine the architecture

of an LUA system.

This section outlines the technically feasible

hardware elements and procedures that could

go into an LUA system. It seeks to give a sense

both of the breadth of possibilities and of the

fundamental limitations. The next section

shows how some of these elements might

come into play in the circumstances of a

Soviet attack. It should be emphasized that

what is being described here are elements of a

hypotheticl future LUA system, not means

which support the present U.S. LUA capability.

The principal elements to analyze from the

technical point of view are targets and the

miIitary utility of an LUA force, the timelines

of possible attacks, early warning and attack

assessment systems, command posts, and

communications I inks. Possible procedures by

which decisions could be made and launch

orders given can be laid out, but a selection

among them would be a decision for the

highest levels of political authority.
Ch. 4—Launch Under Attack ● 149

Targets and Military Utility

The first question to ask of an LUA force is

whether there are important and identifiable

differences, in terms of the military effectiveness of a U.S. response to Soviet attack,

between immediate LUA response and a delayed response executed by a survivable force,

Though there are some d inferences, on balance

it appears that Iittle or nothing from a purely

military point of view is sacrificed by immediate response,

In the first place, there would seem to be no

targets which would be absent or untargetable

early in the war but which would somehow appear later on, Thus, there can be from this

point of view no disadvantage to retaliating

immediately; on the contrary, it wouId seem

that a difference between early and delayed

response, if one were to exist, wouId favor the

early response. The most stressing case for an

LUA system is one in which the Soviet attack

came with no indications of preparation for attack before the actual launch of Soviet missiles. In this case, a prompt U.S. response could

destroy other Soviet military assets before they

had time to disperse from their ordinary

operating bases. I f the Soviet attack came

from a generated posture, some assets might

be difficult to target, but this situation would

not necessariIy improve with time Even if

there were significant Soviet target complexes

that “appeared” later, it is unlikely that they

would be hardened to such an extent that their

destruction would require ICBMS, although if

they were mobile a rapid response-time for

U.S. attack could be useful. Such rapid response is most easily accomplished with

ICBMS, Even assuming the existence of targets

which a survivable force could target but an

LUA force could not, one must assume in addition that the U.S. intelligence assets required

to locate these targets would survive an initial

Soviet attack.

As to the nature of the targets that should be

assigned to an LUA MX force, the important

issue for this purpose is not what these targets

might be, but how the selection might differ

from those assigned to a survivable retaliatory

force. Again, there do not appear to be significant differences. I n either case, the actual targets attacked might well depend upon the nature of the Soviet provocation and have the

goal of inflicting on the Soviet Union a level of

damage – measured overaI I — commensurate

with the damage anticipated from the Soviet

attack, as well as the latter could be judged at

the time the U.S. decision to respond had to be

made. If Soviet silos were among the targets

marked for destruction by the LUA force, one

might want to have some means for determining which were still full and which empty, and

one would also have to take the chance that

the Soviets would themselves launch under attack when our missiles were in flight. Both

problems exist for a survivable force as well. In

practice it is likely that the same information,

obtained at launch, would be used to support

retargeting to avoid attacking “empty holes”

whether by survivable or LUA forces; the only

difference would be the retargeting time available. In practice it is also possible to guess in

advance which Soviet missiles would be used

in an attack on U.S. silos. There is also an

analytical basis upon which to question the

utility of bothering with any sort of “empty

hole” retargeting. (It might even be thought

desirable to attack empty holes to preclude

“reload,”) As to Soviet LUA, with a survivable

force there would be a time delay before retaliation during which efforts could be made

to destroy Soviet sensors capable of indicating

a U.S. launch.

Since decisions would have to be made

quickly, and since extensive ad-hoc retargeting

would be difficult to carry out in the short LUA

timeline, some preplanning would have to be

done regarding the responses to be made to a

given Soviet attack. Such preplanning would

also be done for survivable forces. To the objection that such preplanning is unpleasant or

“commits” the United States to certain types

of response, it can only be noted that the concept of deterrence presupposes, independent

of the forces concerned, that Soviet attack will

provoke with high certainty a U.S. response.

Whether the United States would actually

choose to retaliate if deterrence failed cannot
150 ● MX Missile Basing

be said on the basis of the forces deployed. Of

course, LUA allows Iittle time for reflection if

Soviet attack did occur.

There might be no need to have the entire

U.S. ICBM force postured for LUA, Since a survivable force of, say, 1,000 RVS might be considered adequate for a delayed response, no

more than this number of RVS need be included in the force which “survives” by

launching under attack.

Time lines

Soviet ICBMS take about a half hour to

make the journey from their silos to U.S. ICBM

fields in the Central United States, The time

from first launch to first impact could in principle be shortened by a small amount, but this

would be likely to cause some degradation in

accuracy, A realistic Soviet laydown would

also occur over a span of time, from just under

30 minutes until somewhat later.

Speaking roughly, receipt of the launch message or Emergency Action Message (E AM) by

the missile force as late as a few minutes

before Soviet RVS arrive would be sufficient to

guarantee safe escape of the missiles, This

brief time period would be accounted for by

the time taken for the EAM to be transmitted

to the missile fields, decoded, and authenticated; the time taken to initiate the launch

sequence; the time from first missile takeoff to

last; and the time needed for the last missile to

make a safe escape from the lethal effects of

the incoming Soviet RVS.

Thus, the time available for ICBM attack

assessment and decisionmaking” would be the

half-hour ICBM flight time minus this small

time period for missile launch.

Soviet submarine-launched RVS targeted at

command posts and communication nodes

could arrive earlier than the ICBMS. It is

assumed here that the Soviets would not

possess submarine-launched ballistic missiles

(SLBMS) deployed near U.S. coasts of sufficient accuracy and in sufficient numbers to

constitute themselves a primary threat to U.S.

silos. Forward-deployed SLBM RVS could arrive in the Central United States within 8 to 15

minutes of launch and at coastal targets, such

as Washington, within 5 to 10 minutes. This

means that relatively soft targets such as command bunkers and communications nodes, if

targetable, could be destroyed early in the attack. One of the principal goals of a robust

LUA system must be to survive such a precursor SLBM attack in order to support execution

of a launch decision,

Assuming simultaneous launch of Soviet

ICBMS and SLBMS, the timetable which results

is shown in figure 65.

The LUA timetable could be extended somewhat by a “dust defense” such as described in

chapter 3. In this scheme, the dust cloud

formed by deliberate detonation of buried

nuclear weapons in the silo fields wouId

destroy the first wave of Soviet RVS. The

United States would have until the dust

cleared — tens of minutes — since a second attack could not be mounted during this time.

Overview of Technical Requirements

In order to meet the timeline and attack constraints outlined above, a U.S. LUA capability

would require warning and attack assessment

sensors impervious to disruption; survivable

command posts to digest and organize sensor

information; and secure, reliable communications linking the command posts with the

warn ing sensors and with the missile fields. The

most important requirement, and the most diff i cult to meet in practice, would be providing a

connection from the survivable command

posts to NCA empowered to make launch decisions. This architecture is shown i n figure 66.

Figure 65. —Attack Timeline

. rsf@Qns

1

0 5 10 15 20 25 30

Time (minutes)

SOURCE Office of Technology Assessment
Ch. 4—Launch Under Attack 151

Figure 66.— Launch-Under-Attack System

Architecture

Warning and

attack

assessment

sensors

SOURCE Off Ice of Technology Assessment

The paragraphs below indicate the range of

technically feasible candidates for these system elements It will be apparant that no single

element can be made survivable against a determined Soviet effort to disrupt it. One must

instead make disruption as difficult and timeconsuming as possible, provide redundant

backup systems, and seek to make price of

disruption so high that Soviet attack on all U.S.

LUA assets would virtualIy be cause itself to retaliate against the Soviet Union.

Early Warning and Attack

Assessment Systems

The important features of warning and

attack assessment systems are when in the

course of an attack they couId be expected to

provide information, what information they

could furnish at that time, and how difficult to

disrupt they would be. In general, the first two

features are related in that the more complete

the information they furnish, the later in the attack they do so. Timely information concerning the size and character of the attack would

be vital to the confidence a decision maker

could have in his judgment to fire U.S. nuclear

weapons at the Soviet U n ion. There wouId be a

premium upon confirmation of the facts of the

situation from as many sources as possible. For

this reason it is desirable to have sensors based

on a variety of distinct physical principles.

The following paragraphs outline in general

terms the important features of a wide range

of warning and attack assessment systems that

the United States could deploy to support

LUA. Since even in aggregate the cost of these

systems would be less than the costs of other

MX basing modes, it is not inconceivable that

the United States would deploy all of them

and more.

Satellites

The booster motors of large ballistic missiles, which operate for some minutes after

launch, emit huge amounts of power (hundreds

of kilowatts) in the short-wave infrared portion

of the electromagnetic spectrum. This radiation could be detected by satellites at very

great distances from the earth. It would be virtually impossible for the Soviets to conceal

this evidence of their attack.

Such satellites could provide an accurate

count of the number of launches, the types of

missiles launched (from comparing the brightness of their infrared emission to data from

test launches), and at least the approximate

(wing level)) locations of the launch points.

This information could be available to U.S.

command posts (discussed below) almost immediately. Several minutes more observation

couId lead to at least a very rough indication

of the intended targets, to the extent of

predicting whether the Central United States

(where U.S. silos are) only was under attack or

whether coastal targets were included as well.

This information might suggest whether the attack was directed only at U.S. silos or whether

it was a massive attack on all U.S. targets,

cities (many of which are on the coasts) included. It would not be possible on the basis of

this early information to tell whether the

Soviets had withheld attack on certain specific

targets, an indication of their intentions.

It would not be possibe to secure such satellites absolutely against attack on them, but

such an attack could be made very difficult.
152 ● MX Missile Basing

Though geosynchronous orbit would be most

convenient for such satellites, it could perhaps

be desirable to deploy them in other, higher orbits. Geosynchronous orbit is that unique orbit

22,300 miles from the Earth at which the orbital period of satelIites is equal to the rotation

period of the Earth. Thus satellites in geosynchronous orbit remain over the same point on

the Earth’s surface as both they and the Earth

go round. A single satellite could therefore

keep watch over the Soviet Union at all times.

Because of its convenience, however, geosynchronous orbit is somewhat crowded, It would

therefore be possible for the Soviets to station

a “space mine” near to a U.S. warning satellite

and answer in response to U.S. protests that

the mine was in fact some other sort of satellite (e. g., communications) which it was convenient to position over the Soviet Union. The

United States would then not be in a position

to assert that the Soviets had no business

there, because it wouId be quite plausible that

they did have legitimate purposes for positioning a satellite in this unique, convenient orbit.

If on the other hand the U.S. satellites were in

an orbit chosen more or less randomly from

amongst the infinite number of possible altitudes, we would be in a better position to

assert that the only possible purpose for a

nearby Soviet satelIite must be to interfere

with ours. The United States might then justify

on these grounds measures against such interference. Nonsynchronous orbit means that

more than one satellite would be required to

keep continuous watch on the Soviet Union,

however, since at any one time most of them

would be over other parts of the Earth.

Satellites could also be threatened by direct

attack from a missiIe Iaunched from the Soviet

Union. However, the U.S. satellites could be

positioned high enough that it would take

many hours (18 or so) for an attacking vehicle

to reach them. What is more, since the interceptor missiles required to reach high orbits

would be quite large, the Soviets would probably launch them only from the Soviet Union.

Most of the satellites would be on the other

side of the Earth when the first interceptor was

launched, and launch of other interceptors

wouId have to be staggered so as to intercept

the rest of the satellites as they “came

a round. ” Direct-ascent anti satelIite attacks on

high orbits would therefore present a timing

problem to the Soviets. The United States

wouId most certainly be aware that the satellites were under attack hours before they were

destroyed.

Measure can also be taken to insure the survival of satellites. For instance, they could be

provided with sensors to allow them to determine when they were under attack. They could

maneuver to avoid a horning interceptor and

deploy decoys or chaff to confuse horning sensors. SatelIites at such distances from the Earth

might also be able to be hidden entirely by

giving them small optical, infrared, and radar

signatures. One might also hide dormant backup satellites amongst a swarm of decoys; the

satelIite wouId be turned on when the primary

satelIites encountered interference, Last, backup satelIites couId be deployed on missiIes i n

silos in the United States and launched into

low orbits to replace the primaries. These

reconstituted satellites couId also be attacked,

but it would take time for the Soviets to acquire data on their orbits, even assuming the

United States allowed them unhindered operation of the means to acquire this data. Some of

these techniques for satelIite security are more

effective than others.

Last, the United States might not choose to

show patience indefinitely with persistent

Soviet attacks on our warning sensors, particularly if we had chosen to rely on LUA as the

guarantor of our land-based missiles,

Radars

Radars could be either land-based or deployed on oceangoing ships, Radars deployed

near the United States wouId provide warning

information rather later than satellites —

perhaps 15 minutes or so after launch — but

they would provide much more accurate prediction of the impact points of attacking RVS,

This information would be sufficient to determine which silo wings and which metropolitan areas were under attack.
Ch. 4—Launch Under Attack ● 153

Powerful radars of this sort would be rather

large and soft targets and therefore susceptible to SLBM or even paramilitary attack, jamming is also a potential threat. An endoatmospheric ballistic missile defense could be

provided around such radars. For instance, the

Perimeter Acquisition Radar at Concrete,

N Dak., happens to be in the area selected by

the United States as the only site where an

ABM system can be deployed within the ABM

Treaty and Protocol. The purpose of such an

ABM system would not be to protect the radar

against any level of attack, but to force the

Soviets to send so many warheads to destroy it

that such an attack would constitute a major

provocation

Sensor Aircraft

Aircraft carrying radars (similar to AWACS

aircraft used for tactical purposes) or infrared

sensors could be used either as a backup for

other sensors, taking off from a strip-alert

status at U.S. bases, or as a primary system

maintaining continuous airborne patrol. The

aircraft could be on station within several

hours of takeoff and could provide detailed attack assessment inform at ion (similar in

character to the land-based radars) within

about 15 minutes of impact.

Such aircraft would be a hedge against disruption of satellite or fixed land-based systems If on continuous patrol, they would be

very resistant to balIistic missiIe attack.

Since the aircraft would take some time to

arrive on station if they were not maintained

on continuous airborne patrol, there could be

a gap between destruction of the primary U.S.

systems and reconstitution by the aircraft. This

gap could be filled by rocket-launched probes.

Rocket-Launched Probes

These probes, carrying long-wave infrared

sensors, wouId be simiIar to the probes proposed for the Overlay exoatmospheric ballistic

missiIe defense system to acquire its targets,

They would arrive on station in minutes and

provide detailed attack assessment information simiIar to that provided by the aircraft until they fell back to Earth about 20 minutes or

so after launch. Housed in silos, they would be

vulnerable only to nuclear attack. The probe

silos could be located far from ICBM siIos so

that their launch could not be confused with

ICBM launch by Soviet warning sensors.

Nuclear Detonation Detectors

Since SLBM RVS could arrive on U.S. territory welI in advance of the ICBMS aimed at

the silos and before the time that a launch

decision wou Id have to be made, these detonations could provide further confirmation that

the United States was under attack. Such detectors could be bolted on to large numbers of

satellites deployed for other purposes Alternatively, U.S.-based sensor stations employing seismic or electromagnetic pulse detectors

couId verify that the U.S. was under nuclear attack. It is very unlikely that natural phenomena couId mimic the effects of nuclear

detonations.

Though the detonation of nuclear weapons

on the United States would not by itself necessarily identify the Soviet Union as the attacker, the other warning systems would either

indicate the origin of the attack or be of such a

nature that their disruption could be accomplished only by the Soviets.

Covert Warning Sensors

It might be possible to deploy warning sensors the existence of which could reasonably

be kept secret from the Soviets. Even if this did

not actually turn out to be possible, it would

be a factor the Soviets would have to consider

before they satisfied themselves that the

United States would be without advance

notice of their attack.

Warning Sensors for SLBMS

So far discussion has concentrated on warning of ICBM attack, AlI of the means described

so far are applicable to the SLBM case as well

The satellites would give a launch count immediately and coastal SLBM radars impact

point prediction within minutes of approach to

the coasts. Planes and probes would be relB 83-4770-81-1 1
154 ● MX Missile Basing

atively inefficient in the SLBM role since many

of them would be required to cover all attack

corridors.

Command Posts

Fixed land-based command bunkers of a

hardness sufficient to withstand attack even

by inaccurate SLBMS would be difficultt to construct. The United States now operates a network of fixed command posts including the

National Military Command Center (NMCC) in

the Pentagon, the Alternate National Military

Command Center (ANMCC) at a rural site outside Washington, Strategic Air Command (SAC)

Headquarters in Omaha, and North American

Aerospace Defense Command (NORAD) Headquarters in Cheyenne Mountain, Colo. An improvement on fixed sites would be to deploy a

fleet of wide-bodied aircraft with the necessary communications equipment to receive

and process warning information, communicate with NCA, and launch U.S. silo-based

missiles if given proper authorization. Some of

these aircraft, called Airborne National Command Posts (A BNCPS), could be on continuous

airborne patrol and others on strip alert. The

United States deploys a fleet of such aircraft at

present. If there were advance indication of

imminent Soviet attack, the President himself

or other NCA could take to the air in these

command posts.

Consideration might also be given to ground

mobile command posts, disguised as vans

traveling the Nation’s highways.

Concerns could be raised about possible

means to destroy or disrupt such command

posts, but since they are considered for use

with just about all MX basing modes, any such

problems would not distinguish LUA basing. In

fact such disruption would be very difficultt.

Communications Links

Studies of command, control, and communications (C3

) systems to support strategic

nuclear forces of any kind, LUA or otherwise,

indicate that there is a wide variety of possibilities for wartime communications and just

as wide a range of means to disrupt and impede such communications. The nature of the

disruption would depend on the amount of

damage done to U.S. communications installations and the extent of disruption of the atmosphere due to nuclear explosions. An LUA

C‘ system would have an advantage over systems supporting survivable basing because it

would be needed at a time when the United

States had suffered less damage. On the other

hand, it would be at a disadvantage in that

there might be little time to attempt to reconstItute disrupted I inks.

Many of the same considerations apply to

the communications Iinks which applied to the

warning sensors. None can be protected absolutely against Soviet attack, but disruption

can be made difficuIt, time consuming, and

provocative.

Communications links are required from the

warning sensors to the command posts, from

the command posts to the missile fields, and

between the command posts and responsible

launch authorities. The first two are easier to

specify than the last, since this last depends

sensitively on where the launch authorities are

assumed to be and upon whether they are

under attack or not. A fulIer discussion of the

problems of providing communications systems to support strategic nuclear forces in general is contained in a separate chapter. The following discussion seeks to sketch some of the

considerations relevant to LUA.

Warning Sensors to Command Posts

It appears that satellite communications

would be needed for this purpose, at least for

the warning satellites, since they would not be

connected to the command posts by Iine of

sight. The same cons ideations regarding survivability apply here as for the warning satellites, but the situation is in some respects

easier. To avoid jamming and ionospheric disruption due to high altitude nuclear detonations, these satellites could operate at millimeter wavelengths. They couId be stationed in

unusual, deep-space orbits so the Soviets

couId have no pretense for stationing space
Ch. 4—Launch Under Attack ● 155

mines near them, and direct-ascent interceptors would require a long time to reach them

Since the communications satellites would be

cheaper than the warning satellites, there

could be many of them. other measures —

deep-space storage, concealed dormant

satellites, decoys, maneuverability, etc. — such

as described for the warning satellites could

also be tried here, Rocket-launched reconstitution satellites could be on-station in a short

period There are many U.S. communications

satellites of al I sorts in space, and arrangements could also be made to use them if

the primary system failed.

Fixed ground stations for the downlinks

would be vulnerable to attack, but such attack

wouId at least be required to disrupt them,

They could be proliferated throughout the

United States and even defended with ballistic

missile defense An improvement on fixed

ground stations would use mobile ground terminals, highway-going vans with concealed

receiving dish and data processing equipment,

Data could be transferred from ground stations— fixed or mobile—to the airborne command posts by radio (line-of-sight if necessary)

and satelIite uplink

Ground stations would not be necessary at

al I if arrangements were made for the airborne

command posts to receive data in semiprocessed form directly from the warning satellites

via the communications satellites using millimeter wave or laser I inks.

The sensor aircraft would use satellite links

to communicate with the command posts. The

fixed radars could use radio (line-of-sight if

necessary) or satellite to send their data to the

command aircraft. The rocket-launched probe

wouId be in Iine-of-sight with the command

posts and could communicate directly.

Command Posts to Missile Fields

If an order were given to launch MX missiIes

from their silos, the command posts could

transmit the EAM to the Iaunch control centers

in the silo fields or directly to the silos by a

variety of means, including Iine-of-sight ultra

high frequency (UHF) radio and satellite injection. These methods provide for high probability of correct receipt of the EAM within

minutes, even in a disturbed environment.

Between Command Posts and National

Command Authorities

This is the most difficult part of the communications system to specify, The reason for

this is not that technology does not provide

solutions, but because these solutions could

depend on where the NCA might be, which depends on who the NCA are, which in turn depends on what procedures are adopted for

NCA continuity.

Roughly speaking, there are three cases to

consider. I n the first, the President or other

NCA is in Washington, and Washington has

survived at least to the point in time where a

launch decison is required, Communicant ions in

this case can be by satellite or airborne relay

using a number of aircraft, maintained on strip

alert in peacetime, which form a net over the

United States for UHF line-of-sight commun i cations,

In the second case, the President or other

NCA is himself in a command airplane, Communications is by satelIite or airborne relay.

In the third case, Washington is destroyed

and the President did not manage to make it to

a survivable location, I n this case the important questions are, first: Who and where is the

NCA and can it be arranged that they take

command in time to launch under attack? and

second: Does it matter if we could not LUA?

since it might appear in this case that war was

not going to remain Iimited and our other

nuclear forces wouId be sufficient to acheive

U.S. objectives, The first is a question of procedures and authority and the second of doctrine. They obviously cannot be answered by

technology assessment. Some suggestion of

alternative responses to these questions will

be made in the section below entitled Procedures.
156 ● MX Missile Basing

Pindown

Pindown refers to the possibility that the

Soviets could force our missiles to remain in

their silos by threatening to explode nuclear

weapons in their paths and destroy them in

flight. In practice, however, pindown of silobased MX would require a huge expenditure of

Soviet weapons for an uncertain result and is

therefore not an important threat to LUA.

In a pindown attack, nuclear weapons from

SLEMs and, later in the attack but before

ICBM arrival on U.S. silos, low-trajectory

ICBMs could seek to create an environment

lethal to U.S. missiles in flight. These warheads

would be exploded at high altitudes— about

300,000 ft– in the flyout corridors above the

missile fields. The relevant parameter here is

the number of weapons of a given yield which

must be exploded every minute in the flyout

corridors to ensure that any missile passing

through them is destroyed or disrupted. The

damage is caused by X-rays from the nuclear

explosions, and there are two possible kill

mechanisms. In the first, X-rays are deposited

on the exterior of the missile and vaporize the

surface. When the surface layer is removed,

the recoil momentum is transmitted through

the missile as a compression wave which can

damage the interior of the missile or blow the

backside off. The other method by which the

X-rays could disrupt the missile is by causing

ionization in the electronic circuits of, for instance, the guidance computer.

The flyout corridors above the existing

Minuteman wings are in fact rather large, and

their precise dimensions can to some extent be

made uncertain to the Soviets. I n addition, the

MX missile is planned to be much more resistant to X-rays than Minuteman. The Soviets

would also not know with confidence just how

hard U.S. missiles were.

On the other side, if the Soviets were genuinely determined to try a pindown attack,

they could design warheads especially for this

purpose. These warheads would not need heat

shields since they would not reenter the atmosphere. Thus a warhead of a given yield

wouId be Iighter, meaning more megatonnage

on a given booster.

“The upshot of all this is that, if MX missiles

were distributed throughout the Minuteman

fields, the Soviets would have to explode hundreds of megatons per minute in the fIyout corridors to guarantee pindown. If the Soviets

assumed that no U.S. launch decision could

possibly be made until at least 10 minutes into

the attack, 15 to 20 minutes of pindown would

be required. Timing constraints would demand

that much of this megatonnage be launched

from submarines remote from their home

bases. Pindown would therefore compete with

other time-urgent missions of the forwarddeployed Soviet submarine force and with

secure reserve missions of the remaining force.

These time constraints, combined with the

huge numbers of weapons needed, make pindown an unattractive, if not impossible, Soviet

strategy against LUA for silo-based MX.

(Reckoning strictly on the size of deployment

area, the amount of megatonnage required to

pin down MX in MPS basing would be about

ten times less than for silo basing.)

Procedures

For the U.S. threat to launch under attack to

be credible, procedures would have to be devised to guarantee that the president or other

NCA were able to communicate in timely

fashion with the command posts in a position

to receive attack assessment data from the

sensors and execute the missile force. The

issue here is not whether the U.S. instruments

of command would eventually reconstitute

themselves to wage and terminate a nuclear

war, but whether there would be continuity of

command in the first half hour of the war.

Devising an acceptable set of procedures is a

matter for decision at the highest levels of

political authority. It is not the intention of this

discussion to suggest or speculate what these

procedures might actually be should the

United States adopt reliance on LUA, still less

what procedures support the present LUA capability, but merely to set out the logical

possibiIities.
Ch. 4—Launch Under Attack ● 157

These possibilities are quite distinct depending on the circumstances of the attack I n particular, it matters whether the possibility of attack was foreseen before the actuaI launch of

Soviet missiles (i.e. whether “strategic” warning preceded “tactical” warning) or whether

the attack was a “bolt from the blue” surprise.

Realistic or not, much fear about reliance on

LUA focuses on the second circumstance. Surprise attack is clearly most stressing as regards

the physical capability of the United States to

launch under attack.

It would also be vital whether the Soviet attack had the specific aim of disrupting the U.S.

chain of command supporting LUA. As has

been discussed above, every effort can be

made to preclude the possibility that the

Soviets could deny the LUA capability by

means short ot physical attack upon the NCA,

It appears that such efforts could be quite successful indeed: sensors, command posts, and

communications links could be provided, with

cost and effort, which were very difficuIt to

disrupt. Thus, as a practical matter, the Soviets

could be faced with the choice either of permitting LUA or of attacking directly the U.S.

political leadership. To make this choice the

Soviets would have to ask themselves whether

they preferred to be at war with a nation in

possession of intact national leadership and

usable ICBMS or with a nation in possession of

neither. The U.S. perception of what the

Soviets would intend in making such a choice

could affect the procedures the United States

selected for its LUA system. For instance, if it

were agreed that the Soviets could not intend

anything but total war if they were willing

to “decapitate” the U.S. Government, then it

might be concluded that U.S. bombers, cruise

missiles, and SLBMS were sufficient weapons

to wage such a war. U.S. doctrine might then

state: LUA seeks to deter Soviet attacks short

of decapitation; decapitation attacks are to be

deterred by threat of retaliation upon Soviet

value. On the other hand, if the United States

judged such a doctrine to be inadequate, a

determined effort would have to be made to

devise procedures which would permit LUA in

al I circumstances, The United States might further judge it imprudent to state a doctrine

covering all possibilities, preferring to add

uncertainty to the Soviet decision.

Questions of doctrine would thus have an

obvious effect upon which procedures were

adopted for LUA basing and are just as obviously not susceptible to technical analysis,

In what follows, it is assumed that the United

States would wish to assure the LUA capability

in al I circumstances, and various possibilities

are explored to satisfy this wish. At the point

where these procedures are judged to become

unacceptable, one has the choice of abandoning LUA basing altogether or determining that

the circumstances in question would no longer

require a “survivable” (via LUA) U S. ICBM

force.

The National Command Authority

NCA is the phrase used to describe the

operational institution of the U.S. Government

responsible for decisions to initiate the use of

nuclear weapons. The individuals who occupy

institutional roles comprising the NCA are

called the National Command Authorities (also

NCA). These individuals consist of the President and, upon his death or incapacitation, his

successors as designated by the Constitution

and the Presidential Succession Act; the

Secretary of Defense and his successors; and

the joint Chiefs of Staff and their successors,

these designated by Defense Department

reguIat ions.

The process by which the NCA might order

the use of nuclear weapons by U.S. Armed

Forces has for obvious reasons not been discussed publicly. Hearings conducted by the

House Foreign Affairs Committee in 1974

made clear that no military officer may initiate

the use of nuclear weapons unless authorized

by the President or his successor. In practice, it

appears that many of the procedures for NCA

operation are decided by each President on

the basis of personaI preference.

Attack With Advance “Strategic” Warning

In a period of crisis, it might become apparent either from Soviet statements, from intelligence indications, or from estimation of
158 MX Missile Basing

Soviet reaction to U.S. moves, that nuclear attack was imminent. Such advance warning is

called “strategic” warning to distinguish it

from warning indicating that an attack is actually in progress (“tactical” warning).

One reaction to strategic warning would be

for the President or other NCA to take to the

air in airborne command posts for the duration

of the crisis. There could be concern that this

action, if made known, could heighten tensions and provoke panic in the U.S. public. For

this reason the President himself might wish to

remain on the ground and have a lesser official

assume airborne alert. Whether this could be

accomplished covertly could be questioned

since the command planes would be rather

distinctive. Even disguising them to look like

freight aircraft would be pointless if they took

off from military airfields Iike Washington’s

Andrews Air Force Base. Disguising the movements of high U.S. officials from the press, particularly under the circumstances, might also

prove cliff i cult.

An alternative to providing a “survivable”

NCA would be for the President to decide in

advance the responses to be made to certain

sets of attack assessment data and order that

these responses be executed unless he were

able to intervene to veto or change them. The

responses would be transmitted to ABNCPS,

the crews of which (presumably military officers] would be the executors. Whether such

an arrangement would actually constitute delegation of command authority to others is not

clear, since the precise instructions could be

encrypted and thus totaIIy unknown to the executors.

Surprise Attack Without Decapitation

A “bolt from the blue” attack whose object

was not to disrupt the U.S. chain of command

couId in principle be dealt with by arranging

for the President and other NCA to be at all

times in instantaneous, reliable communications with the command posts which monitor

warning data and launch the ICBMS. As a practical matter, of course, account must be taken

of circumstances when the President is traveling abroad or shaking hands in a crowd.

‘Though it would seem that adequate procedures could be worked out for such cases, they

might be burdensome and obtrusive for the

President and other NCA.

Surprise Attack With Decapitation

l-his would be the most stressing circumstance for a system of LUA. There are several

procedures that couId be devised to meet this

circumstance:

2.

3

LUA fails. This “response,” discussed

previously, considers that this circumstance, implying Soviet willingness to destroy the political leadership of the United

States, would be outside of the range of

contingencies for which ICBM “survivability” is intended. U.S. doctrine could so

state or imply.

Responses decided on in advance by the

President would be executed by ABNCPS

un/ess the President or other NCA intervened to veto or change them. This option is identical to the second option

discussed for the case of advance or “strategic” warning except that in this case

these procedures would be in force at all

times, even when no particular crisis were

occurring. The character of the response

to be made to a given set of warning data

couId be encrypted and known only to the

President. As a hedge against espionage or

revelation of the President’s choices, the

instructions could be arranged to establish only the probabilities that certain

responses would be made, These probabilities couId be made to change on a day-today basis according to the world situation.

The whole set of responses could be

“wired into” the ICBM force or executed

by the intervention of the crew of the

ABNCP.

Launch authority could devolve on the

crew of the survivable command posts.

The NCA could override command post
Ch 4—Launch Under Attack ● 759

decisions if they survived and were in lengthened by preserving the option to

communication. It has been suggested disarm missiles in flight if the NCA chose

that the time during which such NCA in- to veto or change a I au nch decision made

tervention could take place might be by others.

OPERATIONAL POSSIBILITIES FOR LUA

This section illustrates the operational possibilities for a system of reliance on LUA in the

form of attack “scenarios “ These scenarios

a i mat technicaI verisimititude, but no claim is

implied that what happens in them is in any

other sense plausible, much less acceptable.

The range of possible LUA scenarios is IimitIess, and each could be embellished At each

juncture, many different paths could be taken.

The choices made here, when they have any

particuIar rationale at all, are made to

ilIustrate the workings of the technical hardware, It is not thought appropriate for a technology assessment to adopt any other approach.

All the scenarios described assume no advance or “strategic” warning and that the

United States makes every effort to preserve

its capability to launch under attack,

As a reminder of the elements of the LUA

system described in the previous section, the

following list is provided. It should be recalled

that these are elements of a hypothetic/

future system to support reliance on LUA, not

elements of the system that presently supports

the U.S. LUA capability.

National Command Arthorities (NCA)

Fixed Ground Command Post

Airborne National Command Posts (ABNCPs), continuously airbornc or backup strip-alert at Central

U S airbases

Warning satellites

Fixed ground radars

Sensor aircraft, continously airborne or backup

strip -aIert

Rocket- launched sensor probes

Coastal SLBM radars

N U Clear detonation detectors

Communcations satellites, primary and

reconstitutable

The scenarios are organized by timeline with,

T = indicating the time in minutes

Illustrative Soviet ICBM Attacks

on U.S. SiIos Only

These “scenarios” iIlustrate the LUA timeIines for pure countersilo attacks in which no

effort is made by the Soviets to deny the U.S

LUA capability. One might imagine any number of sequences of events leading up to these

attacks. The only important assumption for

these examples of LUA is that strategic warning has either not been received or has not

caused the United States to assume an alert or

“generated” posture. The first, smalI attack is

termed a “demonstration” since, apart from

destroying a subset of US, ICBMS, it would

seem to have no clear purpose other than to

demonstrate Soviet willingness to use nuclear

weapons and to test U.S. willingness to respond, The Soviet attack in the second scenario is the standard “ Iimited counterforce”

attack whose purpose is to destroy the U.S.

ICBM force completely,

Illustrative Small “Demonstrate ion” Attack

T = O: Soviets launch fifty SS-18 ICBMS.

Interim: U.S. fixed and airborne command

posts receive satellite data indicating number and type of missiles launched and Soviet

silo wings of origin. No evidence that SLBMS

are included in the attack. Immediate measures taken to open communications links

with President or other NCA. Backup

ABNCPS, sensor aircraft, and perhaps other

forces alerted,

T = 5: Further satellite data indicates Central

United States as location of targets. Coastal

targets known to be excluded, but targets in

Central United States not further specified.

Backup ABNCPS and sensor aircraft ordered

to take off. Military commanders order

launch of infrared probe.
160 ● MX Missile Basing

T

T

T

= 10: NCA in communication with command

posts and alerted to situation, Probe on stat ion and acquiring data.

= 15: Infrared and radar planes, probe, and

land-based radars all indicate that attack

consists of about 500 RVS. Predicted impact

points correlate with locations of three out

of six U.S. ICBM wings, No evidence of any

other targets.

= 20: NCA orders no LUA since only half of

ICBM force under attack, OR: NCA orders

launch of 50 U.S. RVS targeted at Soviet

SS-18 and SS-19 silos. Simultaneously U.S.

embassies, including Moscow, informed of

intent of U. S, response. OR: Et cetera.

Interim: U.S. ICBMS launch (if applicable).

T = 30: Soviet RVS impact U.S. silos.

Illustrative Full Attack on U.S. ICBMS

T = O: Soviets launch several hundred ICBMS.

Interim: As before.

T = 15: Aircraft, probe, and radars all indicate

T

attack of over 2,000 RVS targeted at all

ICBM wings. No evidence of other targets.

= 20: NCA orders launch of the half of the

ICBM force postured for LUA at Soviet silos

and perhaps other military targets. OR: NCA

orders entire ICBM force launched. OR: Et

cetera.

T = 20-30: As before.

T

Illustrative Soviet ICBM/SLBM Attack

on U.S. Silos and LUA Capability

Excluding Washington

= O: Soviets launch ICBMS at U.S. ICBMS.

Simultaneously, SLBMS from submarines

near U.S. coasts launch at fixed command

posts, fixed communications nodes, fixed

sensors, and airfields supporting airborne

sensors and command posts. All of these

targets are assumed to be located in Central

United States or, if near coasts, not to be attacked. Coastal SLBM radars are not attacked since they collect most of their information before they can be destroyed.

Interim: Continuously airborne ABNCP re1

T

ceives satelIite data’ indicating: number and

types of ICBMs and silo fields of origin;

number, type, and launch locations of

SLBMs. No information about intended targets at this time; therefore not yet clear

whether Washington and other coastal targets under attack. Immediate efforts taken

to open communications I inks with NCA.

Back u p ABNCPS and sensor aircraft

scrambIed.

T:5: Further satellite data indicates Soviet

ICBMS and SLBMS targeted at Central

United States, not coasts; actual Central

U.S. targets not specified. Coastal radars,

however, indicate SLBMS targeted at inland

fixed ground command posts and commun i cations nodes, radars, and airfields where

backup ABNCPS and sensor aircraft are

based. One SLBM RV appears to have

ballistic trajectory which will carry it far

from any U.S. miIitary installation. Military

commanders order Iaunch of infrared rocket

probe,

= 7: SLBM RV with “odd” trajectory bursts at

very high altitude over Eastern United

States. No damage whatever to buiIdings or

popuIat ion from this very high-altitude

burst, but electromagnetic pulse and ionospheric disturbances disrupt some longrange radio and I and Iine communications.

SateIIite communications I inking NCA, fixed

command posts, and ABNCPS is undisturbed.

Interim: SLBM RVS impact Central U.S. targets.

T

Fixed command posts destroyed; command

shifts excIusively to ABNC P. Large number

of RVS targeted at fixed radars saturates

ballistic missile defense; radar destroyed.

Some, though not al 1, backup ABNCPS and

sensor aircraft escape.

❑ 15: Sensor aircraft and probe indicate that

Soviet ICBMs are targeted at U.S. silo fields

only. Nuclear detonation detectors confirm

SLBM detonations, Data made avaiIable to

NCA.

I T=15-20: NCA concludes on basis of inform ation available that Soviet countersilo attack
Ch. 4—Launch Under Attack ● 161

in progress SLBM attack evidently attempted to deny U.S. LUA capability,

T = 20: NCA orders LUA.

Interim: U.S. ICBMs launch.

T = 30: Soviet ICBM RVS impact empty silos,

Illustrative Soviet ICBM/SLBM Attack

on U.S. SiIos, Other Military Targets,

LUA Capability, and Washington

This attack adds the crucial ingredient of

direct attack on Washington, It would seem

reasonable to assume that if the Soviets were

willing to target the U.S. National Capital and

political leadership, they would target also

military targets unrelated to the U.S. ICBM

force or LUA capability such as submarine and

bomber bases. This assumption, made here,

would not affect the U.S capability to LUA

but could make Soviet intentions clearer in the

early minutes of the attack.

T =0: Soviets launch ICBMS and SLBMS,

Interim: Satellites indicate ICBM and SLBM

T

launches. Number and type of ICBMS

launched consistent with countersilo attack.

Number of SLBM launches indicates determined effort to destroy time-urgent U, S,

miIitary capabiIity as well as LUA capability,

Attack judged massive by command posts.

Immediate measures taken to assure

communications between NCA and ABNCP.

Backup ABNCPS and sensor aircraft, as well

as strategic bombers, alerted.

= 5: Further satellite and coastal SLBM radar

data indicate Washington under attack. impact expected at T = 10. NCA notified

urgently by command posts.

Soon after. SLBM impacts on Washington.

ABNCP loses contact with NCA. No procedures to reconstitute NCA in time to LUA.

LUA fails.

OR, as above, until:

T = 5: Peacetime procedures allow for full twoway communications between NCA and

command posts at this time. Informed of

situation, NCA authorizes LUA if Washington destroyed and makes choice among

retaliatory options. Crews of command

posts do not know character of response

chosen by NCA. NCA stays on the line.

Interim: Nuclear detonations on Washington.

T

T

NCA goes off the I inc.

= 12: ABNCP receives confirmation of nuclear detonations on Washington and many

other U.S. targets from nuclear detonation

detectors.

= 15: Probe and sensor aircraft continue to

indicate countersilo ICBM attack. ABNCP

executes LUA according to NCA’S wishes.

Interim: U.S. ICBMS launch.

T = 30: Soviet ICBM RVS impact empty silos.

Attempt to Disrupt U.S. Technical

Capability to LUA Precedes

Soviet Attack

This kind of “scenario” imagines a prolonged “war of nerves” preceding actual

Soviet nuclear attack in the course of which

the Soviets attempt, by means contrived not to

provoke U.S. preemption, to destroy critical

hardware elements of the U.S. LUA capability.

These hardware elements include warning sensors and communications I inks, but not the

NCA. Scenarios like this are sometimes cited as

reasons to distrust reliance on LUA.

No system of warning sensors and communications can be made absolutely resistant

to disruption. Rather, the United States could

make such disruption time consuming for the

Soviets, thus removing any element of surprise,

and requ ire that the means to disruption be extensive, provocative, and even overtly hostile.

As a practical matter, one can also make a subset of the system virtually immune to disruption. Whether this residuum could be considered sufficient to support a U.S. LUA decision is not clear, but it could impose on the

Soviets the concern that even if they accomplished the disruption of the rest of the

system, the United States might still be able to

launch under attack. Above all, of course, the

Soviets would have to consider that before
162 ● MX Missile Basing

their attempts at disruption had succeeded,

the United States might preemptively attack

them or at least inflict comparable damage on

their systems.

The satellites are the element which, while

susceptible to disruption, would take the

longest to destroy. Direct-ascent antisatellite

interceptors would take some 18 hours to

reach the high orbits where the satelIites could

be placed. The United States would thus have

ample warning that disruption was in progress.

As a practical matter, such high-altitude direct

attack would also be quite difficult for the

Soviets to execute and would be subject to

various U.S. countermeasures, as discussed in

the previous section. It would also seem that

Soviet preparations for such an attack could

scarcely be concealed; for one thing, the

boosters required would be the size of SS-18s

or Iarger.

Space mines are a means whereby the satellites could be destroyed instantly, once the

Mines were emplaced. As discussed in the

previous section, unusual orbits could be

chosen for U.S. satellites. The United States

could reasonably assert that Soviet placement

of space vehicles in the same or nearby orbits

could have no other purpose than to disrupt

the U.S. LUA capability.

1 n either case – direct-ascent interception or

space mines — there would be no question of

“surprise” attack. The United States could in

addition possess the capability to launch a set

of replacement satellites (perhaps less sophisticated and presumably in lower orbits) before

Soviet disruption of the primary system were

complete. These replacements, too, could be

attacked, but this attack would also take time.

Supposing the United States permitted disruption of its warning satelIites, still the airborne sensors, land-based (and perhaps shipbased) radars, and the rocket-launched probe

W ould remain. One can conceive of threats

(sabotage, close-in jammers) to the groundbased radars, but barring this, they could be

hardened to the point where their destruction

required nuclear attack. The probes couId also

be in hardened silos. Associated BMD systems

could increase the price of destruction by

ballistic missile attack.

Supposing now that the satellites and the

radars and probes were destroyed, the sensor

aircraft would still provide warning and attack

assessment. It is generalIy believed that aircraft operating i n North American airspace in

wartime would be difficult for the Soviets to

attack. These aircraft could operate out of

their home airfields and, presumably, civilian

airfields for long periods. Thus in a period of

prolonged conflict, in which other U.S. sensor

assets were destroyed and the United States

wished maintain an LUA capabiIity, these

aircraft might provide enduring warning and

attack assessment. Though not providing warning of Soviet attack at launch, they wouId stiII

provide notice of attack within 15 minutes of

the time a launch decision was required. Under

the circumstances, U.S. decision makers would

presumably put themselves in a position to

make rapid decisions.

“Thus, a Soviet attempt to deny the U.S.

warning and attack assessment capability

could be made exceedingly difficult and risky,

if not impossible. A similar analysis could be

performed for the communications links described previously. Thus, vuInerabiIity of the

technical elements of the LUA capability need

not be an “Achilles’ heel” for reliance on LUA.

Whether the procedures supporting decisionmaking can be made as robust is another matter, as has been discussed extensively.

SUMMARY OF CRITICAL ISSUES FOR LUA

This section summarizes the critical issues issues, and most certainIy judgments regarding

that might enter into a decision to rely on LUA them, are in the end nontechnical. Though

as the guarantor of ICBM “survivability. ” As is technical analysis can further define these

apparent from this chapter, some of these issues, it cannot resolve them. Certain of these
Ch. 4—Launch Under Attack 163

issues apply in some measure to survivable

basing as well as to LUA; what matters for purposes of comparison are the differences between the two types of basing. For instance,

that certain circumstances of LUA are unpleasant is obvious, but it is not clear in al I cases

that they are improved by delaying response.

It must be borne in mind that the observations made here apply to a hypothetical future

system of reliance on LUA, not the means

which support the present LUA capabiIity.

Information Available to

Decision makers

Decisionmakers would require information

concerning the extent and intent of a Soviet attack and confidence that this information was

accurate. Technical analysis can specify which

data might be available at certain times in the

course of an attack but cannot suggest what

information might be considered adequate

to support a decision to launch offensive

missiIes.

In general, the earlier in the attack a sensor

acquired information, the less detailed it

wouId be Thus, at the time of Iaunch, the

number, type, and origins of boosters launched

could be specified Several minutes later, it

couId be possible to determine whether the entire United States was under attack or just a

portion thereof By midcourse (15 minutes

from launch and 15 minutes before impact),

the impact points of RVS could be predicted.

The locations of detonations of submarineIaunched RVS on the United States might also

be known By this time, only 5 to 10 minutes

wouId remain for decision making

One might legitimately question whether, if

the United States possessed a survivable ICBM

force, better information that this would be

available to support a retaliatory decision

within a short time. That is, given the widespread confusion and disruption of communications following even a small attack, the information supplied by warning sensors in the

first few minutes might in fact be the most

complete available for a long time after the attack. Deployment of a survivable force might

actualIy lead the United States to deploy fewer

and less robust sensors than it would deploy it

relying on LUA, Thus, as a practical matter, the

information upon which to gauge response

could conceivably be less with survivable

forces than with LUA

Despite the redundancy and technical variety of the warning sensors, there could be

reluctance on the part of decision makers to

base launch decisions on information collected by such remote means.

Decision Timelines

Depending on the circumstance, the amount

of time available for deciding on a response to

Soviet attack could range from an upper limit

of 20 minutes to no time at all. Meeting this

timeline would probably require at least some

provisional advance planning by the President

and other NCA.

Possibilityies for Diplomatic and

Other Activities

The LUA timeline would leave no time for

diplomatic activities between attack and

response. At very least, such activity could

serve to signal to the Soviets U.S. perceptions

of their attack and the intent of any U.S.

response, Communication with other governments, U.S. overseas installations, and U.S.

military forces worldwide might also be accomplished at this time.

However, it is not clear to what extent the

circumstances of nuclear war, especially as

regards disruption of communciations, would

permit such activities within a short period of

an initial attack anyway.

Providing for Launch Authority

Timely command decisions by authorized

NCA is clearly a requirement for reliance on

LUA,

This requirement would be most difficult to

satisfy if the Soviets intended deliberately to

destroy or “decapitate” the NCA. In this circumstance, possible options might be: LUA
164 ● MX Missle Basing

fails (not intended for this extreme case); provision is made for very early NCA decision; decisions decided on i n advance by the NCA are execu ted by others if the NCA does not veto or

change them; launch authority is delegated to

others than the NCA.

Which of these options, if any, would be acceptable is a matter not of technology but of

decision at the highest levels of political

authority.

Even in the less extreme case in which no attack on the NCA is intended, provision must be

made for the NCA to be available at al I times

for rapid decision. Such procedures might be

onerous for the President and other NCA,

Fear That U.S. LUA Capability Could

Somehow Be Sidestepped

The analysis presented here indicates that,

from a technical point of view, sensors and

communications could, with money and effort, be provided to make at least the technical

elements of the LUA capability exceedingly

difficult, if not impossible, for the Soviets to

disrupt. Procedures to support decisionmaking

are another matter, Even if both hardware and

procedures were devised which were very

robust indeed, it might not be possible to

eradicate completely a lingering fear that the

Soviets might find some way to “sidestep” the

system. These fears could become aggravated

at a time of crisis.

Risk of Error

There are two risks of error in a basing

system of reliance on LUA: the risk that launch

Wou

and

d take place when there was no attack,

the risk that launch would fail to take

place when there was an attack.

Insofar as technology is concerned in the

assessment of these risks, one can i n principle

make arbitrarily small the probability that

electronic systems by themselves make either

kind of error, though beyond a point efforts to

decrease the chance of one error could increase the chance of the other.

But it would seem that the principal source

of error might not be electronic or mechanical

malfunction by itself, The odds that a sensor

indicates something out of the ordinary might

be quite high, but the chances that it indicates

something resembling a plausible Soviet attack would be much smaller, The probability

that severa sensors based upon different

physical principles indicated the same plausible attack would be much smaller still. That is,

electronic systems tend to make random,

rather than highly structured, errors. On the

other hand, electronic systems have a very

limited ability to correct errors once made.

Human beings, by contrast, have a high capacity to correct errors, but also a high capacity to commit highly structured errors. The

risk of error for an LUA system would seem

highest when the human being’s ability to

make highly structured errors combines with

the machine’s limited ability to correct them.

Mistakenly initiating a “simulated” attack by,

e.g., loading the wrong tape into a computer,

would be an error of this type. It is obviously

not possible to set and enforce a bound on the

probability that such an error could occur in

an LUA system.
Chapter 5

SMALL SUBMARINE BASING OF MX

Chapter 5.—SMALL SUBMARINE BASING OF MX

Submarine Basing of Strategic

Nontechnical Considerations

Technical Choices Leading to

Page

Missiles .. .167

. . . . . . . . . . 167

Small Submarines . . . ............169

Description and Operation of the Small

Submarine System. . . . . . . . . . . . . .170

Introductory Remarks. . . . . . . ........170

Overview . . . . . . . . . ...............171

Communications System and

Operational Procedures . ..........173

Submarine Navigation and Mapping

Needed for High Missile Accuracy .. .174

Missile Guidance Technologies . . . . . . .175

Vulnerability. . . . . . . . . . . . . . . . . . . . . . . .176

Tactical and Strategic Applications of

Antisubmarine Technologies . . . . .. 177

Theory of Open Ocean Barrage . . . . . . .178

Open Ocean Barrage With No

Information About Submarine

Locations . . . . . . . . . . . . . . . .. ....179

Open Ocean Barrage After Detection

of Snorkeling Submarines . . . . . . . . . 180

Searches With Technologies That

Observe Nonsnorkeling Submarines. .182

Increased Range Acoustic Technologies. 184

Page

Increased Radar Search Using Satellites. 186

Countermeasures to Radar Satellites .. .189

War of Attrition . . . . . . . . . . . . . . . . . .189

Van Dorn Effect . . . . . . . . . . .. ...190

Theory of Trailing. . . . . . . . . . ........191

Establishment of Trail at Port Egress. . .193

Establishment of Trail Using Large Area

Open Ocean Search . . . . . . . . . .196

Diesel-Electric Propulsion Technology. .197

Nuclear Electric Propulsion . . . . . . . .198

Concluding Remarks on the

Vulnerability of Submarines . . . . .199

Factors Affecting the Accuracy of Landand Sea-Based Missiles . . . . . . . 199

Accuracy of Small Submarine Based MX .. 202

Accuracy of Star-Tracker-Aided Inertially

Guided MX . . . . . . . . . . . . . . . . . . . . .205

Degradation in Accuracy After a

Submarine Navigation Fix. . . . . . .. ..206

Inertial Guidance Aided by Radio Update .207

Time on Target Control. . . . . . . . . . . . . . . .208

Responsiveness of the Submarine Force. . .209

Endurance of Force. . . . . . . . . . .210
Cost and Schedule . . . . . . . . . . . . . . . . .

System Size. . . . . . . . . . . . . . . . . . . . . . .

Final Sizing Consideration . . . . . . . . . . .

Location and Description of Bases. . . . .

TABLES

Tab/e No.

21. SubmarineObservables . . . . . . . . . .

22. Acoustic Sensors forSubmarine

23

24

25

26

27

28

29

Detection . . . . . . . . . . . . . . . . . . . . .

Nonacoustic Sensors for Submarine

Detection . . . . . . . . . . . . . . . . . . . . .

Operational Factors Affecting Radar

Search of Submarine Deployment

Areas. . . . . . . . . . . . . . . . . . . . . . . . .

Miss Sensitivities tolnitial Errors for

ICBMTrajectories. . . . . . . . . . . . . . .

Comparisonof Hard Target Kill

Capabilities of Sea-Based MX With

Design Requirements of the LandBased MX . . . . . . . ., . . . . . . . . . . . .

Small Submarine 10-Year Lifecycle

cost. . . . . . . . . . . . . . . . . . . . . . . . . .

Number of Submarines Required To

Page

. . 210

. . 212

. . 213

. . 213

Page

. . 177

. . 177

. . 177

. . 182

. . 201

. . 203

. . 211

Keep 100 MX Missiles Continuously on

Station v. Submarine In-Port Time .. ..213

Estimated Characteristics of the Small

Submarine Refit Site and the Trident

Refit Site. . . . . . . . . . . . . . . . . . . . . .. .214

FIGURES

Figure No. Page

67, Nuclear and Nonnuclear Powered

68

69

70

71

Submarines of Different Size . .......171

Encapsulated MX Missile . ..........172

MX-Carrying Diesel-Electric Small

Submarine. . . . . . . . . . . . . . . . . . . . . .. 173

Sequence of Events During the

Launch of an Encapsulated MX Missile. 173

Number of Weapons Required to

Figure No. Page

72.

73.

74.

75.

76.

77.

78

79

80

81

82

83.

84.

85<

86,

87

88

Destroy Submarines That Have Been

Sighted Prior to a Preemptive Attack .. 179

Potential Deployment Area Given

1,000- and 1,500-nmi Operating Ranges 180

Large Area Search With Technology

That Can Only Detect Snorkeling

Submarines. . . . . . . . . . . . . . . . . . . . . .181

Sources of Reverberation That Limit

the Capability of High-Powered Active

Sonars. . . . . . . . . . . . . . . . . . . . . .. ...183

Potential Whale Sonar Targets . ......185

Fishing Vessel Monitoring, ., . .......187

Ground Track of Radar Search Satellite 188

Van Dorn Effect . .................191

Active Acoustic Search for a

Submarine That Has Dispensed

Decoys Which Simulate a RefIected

Sonar Signal From a Submarine Hull. .. 194

Passive Acoustic Search for

Submarine That Has Dispensed

Decoys Which Simulate the Sound

of a Submarine . . . . . . . . . . . . . . . . . , .195

German Type 2000 Submarine . ......197

Factors Affecting the Accuracy of a

Ballistic Missile. . . . . . . . . . . . . . . . . . . 200

Down Range and Cross Range Errors

of a Ballistic Reentry Vehicle at a

Target . . . . . . . . . . . . . . . . . . . . .. ....202

Accuracy of Inertially Guided SeaBased Missile at Different Ranges

From Targets. . . . . . . . . . . . . . . . .. ...202

Accurary of Star-Tracker-Enhanced

Sea-Based Missile as a Function of

Range From Target . . . . . . . . . . . . . . . .206

Ocean Areas That Provide Adequate

Line-of-Sight View of Ground Beacons

on Continental U. S., Aleutian Islands,

Alaska, and Hawaii . . . . . . . . . . . . . . . .208

Ocean Areas That Provide Adequate

Line-of-Sight View of Ground Beacons

on Continental U. S., Aleutian Islands,

Alaska, Hawaii, and Selected South Sea

Islands. . . . . . . . . . . . . . . . . . . . . . . . . . 209

Small Submarine Program Schedule. .. 211
Chapter 5

SMALL SUBMARINE BASING OF MX

SUBMARINE BASING OF STRATEGIC MISSILES

Strategic missiles are based on submarines

because submarines can be hidden in vast expanses of ocean, thereby gaining a high degree

of survivability. Currently, the United States

takes advantage of the survivability of submarnes to deploy the Polaris, Poseidon, a n d

Trident I missiles. Unlike attack submarines,

whose primary mission is to protect convoys or

attack enemy shipping, these balIistic missile

carrying submarines seek to avoid surface

ships and remain undetected, available for

strikes against enemy targets on command.

The object of basing MX on submarines would

be to take advantage of the same survivability

that has been demonstrated by experience

gained with the Polaris and Poseidon systems.

One major question addressed in this chapter

is whether this survivability can be expected to

continue into the 1990’s

MX has been conceived as a land-based

intercontinental ballistic missile (I CBM). The

land-based ICBM has historically had greater

accuracy, flexibility of targeting and rapidity

of response than that of sea-based missiles. As

a land-based ICBM, the MX missile is expected

to set still a new standard in each of these attributes relative to previously deployed landbased missiles. The second technical question

that is to be addressed in this chapter is the extent to which this new standard of attributes

could be preserved if the MX were instead

based on submarines.

Deploying the MX at sea rather than on land

wouId also raise questions about how important it is to mix and balance the different attributes of nuclear forces to best deter war.

The different points of view are summarized

here, but these issues cannot be resolved by

technical anaIysis.

This chapter begins by noting some of the

principle rationales and drawbacks of submarine basing of MX. Some of these issues,

while clearly relevant, are just as clearly not

technical issues per se. The following sections

attempt to more closely define and analyze

technical and operational issues that bear on

the problem of submarine deployment of a

large, flexible, counterforce ICBM like MX.

The conclusions of these technical analyses

are summarized in the last section.

NONTECHNICAL CONSIDERATIONS

Much of the interest that has been shown in

submarine basing of MX is motivated by the

perception that the survivability of a future

submarine force is Iikely to be insensitive to

the nature and size of the Soviet ICBM force.

As long as the Soviets are not able to develop

an ability to localize and track submarines, the

only conceivable way they could preemptively

attack the submarine force with ICBMS would

be to randomly barrage suspected submarine

operating areas. If the Soviet ICBM force were

to grow in its ability to deliver large amounts

of megaton nage, submarine operating areas

could merely be expanded in size to counter

such a threat. I n addition, the Soviets could

gain no additional ability to threaten the survivabiIity of submarines through improvements of accuracy technology or through fractionating the warheads on existing or new

ICBMS. Thus, provided that submarines maintain their ability to hide in vast expanses of

ocean, there would be little or no way to

threaten their survivability with either a

substantial expansion, or with technical

improvements, of Soviet ICBM forces. A decision to deploy the MX missile at sea in submarines would therefore negate the effectiveness of the Soviet ICBM force as a means

of threatening the MX missile. This decision

could diminish the political leverage that the

167
168 ● MX Missile Basing

Soviets have bought with their modernized

ICBM force by removing their ability to

threaten a major U.S. strategic weapon system.

A perspective that argues against the basing

of MX on submarines holds that moving missiles off the land will result in fewer disincentives to an adversary who is contemplating the

use of, or the threat of using, nuclear weapons

as a means of extracting political concessions

from the United States. This perspective views

the basing of strategic missiles on land as insurance against political blackmail. An adversary who attempts to gain political advantage

by threatening U.S. strategic systems with

nuclear destruction would, in effect, be forced

to threaten targets on American soil. Landbasing would make the price of attempts to

gain political leverage in this manner very

high, thus decreasing the likelihood of such

blackmail.

Some who argue this way also believe that

the United States wouId lack the resolve to respond to Soviet threats unless it was clear that

the continental United States was threatened

with nuclear attack, They fear that such lack

of resolve could make nuclear war easier for

an adversary to contemplate, thereby making

it more Iikely.

Others disagree with these perspectives and

argue that there is a beneficial effect of removing potential targets from the continental

United States. Since there would be no clear

gain in an unsuccessful attack against a survivable sea-based system, there would be no incentive to attack strategic systems. They argue

that a land-based system that presents a

serious threat to Soviet military systems could

invite attack if a crisis deteriorated to the

point where Soviet decisionmakers believed

war was unavoidable. I n such a circumstance,

Soviet decisionmakers might attempt to limit

damage to their own systems by striking first.

If a submarine-based system were untargetable, a rational Soviet decisionmaker would

be denied such a choice. Thus, submarine basing wouId have the stabilizing effect of forcing

a wait-and-see attitude on decision makers during periods of international crisis.

A potentially serious drawback of basing MX

missiles on submarines is that the system could

share a common mode of failure with Trident

and Poseidon if an unforeseen antisubmarine

warfare capabiIity emerged in the next 20

years. Since the United States, with its substantial commitment to undersea warfare, has

been unable to identify or project any threat to

ballistic missile submarines, the significance of

such a potential drawback is difficuIt to

evaluate.

Another potential drawback is that a submarine-based system would require highly skilled

and trained personnel that are not currently

available in the Navy. In order to meet additional manpower needs, training centers would

have to be established and recruiting efforts

would Id have to be expanded. I f the civiIian

economy was healthy, competition for trainable people could make it difficult to attract

them into the Navy. It could also be difficult to

retain personnel once they have developed

skills because of the attraction of lucrative

civiIian jobs.

‘Submarine construction presents somewhat

different problems from that of surface ship

construction. Past experience indicates that if

shipyards do not demonstrate a good deal of

competence constructing surface ships, they

wiII have very great difficulties constructing

submarines. Since the volume available for

equipment and crew in a submarine is very

small relative to that available on surface

ships, construction must be carefully planned

so that components can be put into cramped

locations in the proper sequence. Quality control is also important since equipment and

components may be subjected to extreme conditions during the course of submarine operations.

Constructing a new fIeet of MX-carrying submarines wouId be a major undertaking. Three

shipyards not currently engaged in submarine

construction would probably be needed to

construct submarines if the full fleet is to be

deployed by 1992 or 1994. Each shipyard

wouId have to be provided with a smalI team

of people experienced in submarine construc-
Ch. 5—Small Submarine Basing of MX ● 169

tion to help it make an orderly transition to

submarine construction. Lack of experience in

submarine construction couId resuIt in program delays if the shipyards had not been

carefulIy chosen for their efficiency and competence or if they did not have adequate guidance on submarine construction techniques

Delays could occur in other submarine construction programs as well, if the base of

special materials required for submarine construction were not expanded to meet increased

demands. It is also possible that if problems

developed within the MX submarine program,

talent, effort, and funding might also have to

be diverted from those programs.

Other problems could arise with other

elements of the project due to the timing of

the missile development program If missile

development were delayed a year by design

changes required for sea basing, it would be

ready for deployment in 1987 The design,

development, and construction of a new class

of submarines could in theory be expedited to

produce lead ships by late 1987, but this appears unlikely. If the program proceeded at a

rate more characteristic of recent strategic

weapons programs, the lead ships would not

be deployed until 1990. The missile could

therefore be ready for deployment several

years before there are means to deploy the

missile. It would be necessary to keep missile

scientists, engineers, and managers available

for the testing and monitoring phase of the

missile deployment. These individuals might

have to be retained at great cost until the

deployment is far enough along to assure that

unforeseen problems had not emerged.

These perspectives, among others, involve

judgments of a nontechnical nature and will

not be addressed further in this chapter. Instead the focus will be on assessing the technical strengths and weaknesses of a sea-based

MX system that was optimized to perform the

missions usually ascribed to ICBMS.

TECHNICAL CHOICES LEADING TO SMALL SUBMARINES

If an MX-carrying submarine force is to be

specificalIy optimized to capture as many attributes of the land-based lCBM as possible,

there are two attributes of the land-based

I C BM that suggest smaII submarines carrying a

few missiIes are preferable to large submarines

carrying many missiles These attributes of the

land-based missile are

1. fIexibility of targeting that does not compromise survivability of unused missiIes in

the force, and

2. diversity in failure modes with the other

legs of the Triad

Flexibility refers to a weapons system’s ability to select and carry out preplanned attack

options, or attack options that are subsets of

preplanned attack options It also includes the

abiIity to carry out ad hoc attacks against targets that may be on the National Target Data

Inventory List or targets that are specified only

in terms of geographical location

Since a large ballistic missile submarine carries military assets capable of delivering enormous destruction against an adversary’s targets, it is itself a target of considerable military

importance, I f the submarine’s position were

to become known in wartime, there wouId be a

substantial incentive to attempt to destroy it.

If a flexible tar-getting strategy were adopted

for a submarine force, submarines might be

ordered to fire a Iimited number of missiles at

enemy targets. The firing of these missiIes

could potentialIy reveal the position of the

submarine to enemy surface ships at great distances, to space-based sensors, radar systems,

and possibly even sonar systems. The expected

postlaunch survivability of a missile-carrying

submarine is therefore quite different from

that of its expected prelaunch survivability

The flexible use of this force could therefore

resuIt in attrition that wouId compromise its

abiIity to continue the war or force termination of the war
170 ● MX Missile Basing

If flexibility of targetting is specifically

desired in a submarine force, it would be necessary to make the survivability of remaining

missiles as independent of previously

launched missiles as possible. This could be

done if the submarine force was made up of a

large number of submarines each carrying a

small number of missiles. If this were the case,

then the wartime loss of submarines that

placed themselves at risk by launching only a

few of their missiles would not result in the

loss of a large number of remaining unused

missiles. The force would therefore be able to

carry out limited nuclear attacks without compromising its ability to carry out subsequent

massive strike missions.

Another reason that submarine-based strategic weapons have been less flexible than landbased ICBMS in the past is that communications with submarines have historically not

been as good as those achievable with landbased systems. As will be discussed later in this

chapter, flexibility in targetting could be

achieved with the current submarine force if a

conscious decision were made to acquire certain kinds of communications capabilities and

to adopt certain operational procedures.

Diversity in failure modes with other legs of

the Triad is a more difficult attribute to

discuss, since it involves making judgments

about threats that have not yet been identified. If the MX missile were deployed on

small submarines, it seems more probable that

it would share a common failure mode with

other submarine-based systems than would a

land-based system. The likelihood of such a

breakthrough must be considered remote in

the absence of any scientific evidence to support such a possibility. However, if an unforeseen antisubmarine capability developed in

the future, it is possible there could be quantitative and/or qualitative differences between

sea-based Trident/Poseidon submarine forces

and submarine-based MX that could make the

threat less effective against such diverse types

of submarines. Small, slow-moving submarines

would in fact have certain signatures that are

different from those of larger, faster moving

submarines. In addition, a fleet of many submarllnes poses both a qualitatively and quantitatively different set of operational problems

to an antisubmarine force than does a fleet of

a few submarines. With this in mind, it could

be argued that a fleet of MX-carrying submarines would increase the diversity of strategic nuclear forces, making it less likely that a

single technology could threaten all three legs

of the Triad.

DESCRIPTION AND OPERATION OF

THE SMALL SUBMARINE SYSTEM

Introductory Remarks

If the MX were to be deployed on a fleet of

submarines, there wouId be many engineering

and operational tradeoffs that would have to

be made if the fleet was to be an effective

weapon system. 1 n order to establish conservative bounds for what is Iikely to be achievable, OTA has postulated a system of submarines, operational procedures, and communications that is specifically optimized to attain

ICBM-like flexibility and responsiveness while

still basing MX on submarines. The system concept to be described and evaluated is based on

off-the-shelf technologies, and Navy operational experience and practices wherever

possible. However, it should be expected that

if a national decision were made to deploy MX

on submarines, many technical features of a

new system of MX-carrying submarines would

likely be different from those postulated for

OTA’S analysis of small submarine basing. A

new class of submarines would have to be

designed and built. New and different procedures would also be evaluated and developed for the submarine operations. Such a vast

enterprise as the design, construction, and

deployment of a new and modern strategic
Ch. 5—Small Submarine Basing of MX ● 171

weapon svstem could result in a system with rines to carry 100 alert MX missiles for delivery

features different

discussed here

from the system that will be of highly accurate warheads against Soviet

targets. It is believed that these submarines,

Overview

The submarine system to be described uses a

combination of communications, navigation,

and guidance technologies aimed at maximizing flexibiIity of targeting, rapidity of response, and missiIe accuracy. Submarine operational procedures are set up to allow submarines to carry out launch orders issued by

the National Command Authorities (NCA) rapidly. There would always be enough submawhile at sea, would be untargetable and impervious to Soviet preemptive actions (this

issue is discussed fully in the next section) This

submarine force is therefore optimized to

carry out missions similar to those commonly

ascribed to ICBM forces.

The basing system would consist of a force

of 51 moderate-sized (see fig. 67) dieselelectric submarines each of which is armed

with four MX missiles. The submarines could

also be powered with small, low-enrichment

Figure 67.—Nuclear and Nonnuclear Powered Submarines of Different Size

Nuclear powered

NR-1

136’ X 13’

Nuclear powered

Trident

42’ X 560’

OTA diesel-electric

25’ X 342’

German Type 2000

small diesel-electric

25’ X 200’

Nuclear-turboelectric

SSN-597 (Tullibee)

SOURCE: Office of Technology Assessment
172 ● MX Missile Basing

nuclear reactors. During normal operations, 28

submarines would be continuously at sea, In

periods of crisis or international tension, submarines in refit (but not those in extended refit

or in overhaul) could be surged from port to

raise the at-sea numbers to 38 to 40. This

deployment would provide an additional 400

warheads on station.

The MX missiles would be carried in steel

capsules approximately 80 ft long and 10 ft in

diameter (see fig. 68), The capsules would be

carried outside the pressure hull on the top

side of the submarine’s huII (see fig. 69).

On a launch command (see fig. 70), hydraulic actuators would open doors on the submarine’s fairings and straps within the fairings

would release the capsule. Soft ballast would

then be blown from the front end of the capsule causing it to rise and rotate toward the

vertical. Upon sensing the ocean surface, the

top and bottom caps on the capsule would be

cut free, the missiles motors would ignite, and

the thrust of the first stage motor would propel

the missile from the capsule.

After missile flyout, a flotation collar and/or

drag surface would deploy from the empt y

capsule to slow its descent into the ocean. This

wou Id lower the risk of a COIIision between the

expended capsuI e and the submarine.

The submarines would deploy from dedicated bases in Alaska and on the east and west

coasts of the continental United States, Each

base would, on the average, have 5 to 6 submarines in port at al I times. The submarines

wouId be at sea for 60 days and in port for refit

and logistic support for 25 days.

The submarines would typically operate as

far as 1,000 nautical miles (nmi) from port.

They would be designed to have sufficient

speed and endurance to operate at stiII greater

distances from port (1 ,500 nmi or more) if such

operations were deemed desirable. Each submarine would have an advanced submarine

Figure 68.—Encapsulated MX Missile

Shock isolation

Steel capsule

Small-diesel

Trident

SOURCE. Off Ice of Technology Assessment
Ch. 5—Small Submarine Basing of MX ● 173

Figure 69.— MX”Carrying Diesel. Electric Small Submarinea (3,300 tons submerged displacement)

Computer

Engine room Galley messing ---- -

T launch T

Communicaton

Forward

I

I I

aSubmarlne design developed by consfdenng the characteristics of the most recent U S,.bwlt diesel submarines, the SS580, the SSG557 GROWLER Class REGULUS

mlssl Ie submarine, current technology represented In the Federal Republ IC of Germany submarine designs (H DW Type.209 and Type-2000 designs), and other advances

demonstrated In Swedwh and Nethedand designs Proven technologies incorporated Into design are maximum quletlng achewable by sound fsolation, a(r coupling of

electrtc drive motor to screw shaft, faster recharging at lower snorkel noise levels, Increased battery capacity, microprocessor monitoring and management of power

systems, and smaller crew size

SOURCE Off Ice of Technology Assessment

Figure 70.—Sequence of Events During the

of an Encapsulated MX Missile

A

Launch

 - “t ’

SOURCE Office of Technology Assessment

inertial navigation system (E SCM/SINS), a

velocity measuring sonar

system for interrogating

spenders, and equipment

the Global Positioning

LORANC.

(VMS), an acoustic

prepositioned tranfor taking fixes on

System (GPS) and

Missile accuracy would be maintained mainly with onboard submarine navigational equipment. This equipment would occasionally be

updated with the G PS or a covert system of

acoustic transponder fields. If the GPS were

destroyed by enemy action, the occasional

navigational updates would be done with the

acoustic transponder fields.

Communications System and

Operational Procedures

The communications system and operating

procedures would be configured so that the

submarines in peacetime would constantly be

receiving communications from NCA through
174 ● MX Missile Basing

trailing wire antennas and/or buoys that would

constantly receive shore to submarine very low

frequency (VLF) communications. In addition,

the submarines could also be in two-way communications with NCA using a covert, rapid

and reliable high-orbit satellite transponder

link. This link would allow for the submarines

to report back to NCA and make possible high

data rate reception of information for rapid

retargetting of the force.

Since shore-based VLF stations would probably be destroyed if there was enemy preemptive action, communications with the submarines would then be maintained via survivable airborne VLF relays, that could immediately replace shore-based VLF stations.

These airborne relays would maintain radio

siIence and would be continuously airborne

unless they were needed to replace shorebased VLF transmissions. Emergency Action

Messages (EAMs) could be routed from NCA,

through either the shore-based VLF stations, or

the airborne VLF relays, to the submarines. (Today these airborne relays are known as

TACAMO aircraft. TACAMO is an acronym for

Take Charge And Move Out).

If there was a need for high data rate

retargetting, or for two-way communications,

designated submarines would be ordered via

the VLF radio link to prepare for high data rate

or two-way communications. I n order to do

this, the submarines would erect a mast above

the ocean surface to permit communication

through the high-orbit satellites mentioned

earlier.

If there was a need for the submarine to report back to NCA, the submarine could beam a

message through the satellite using a 5-inch

dish antenna which would be mounted on a

mast.

The probability of an adversary detecting or

intercepting such transmissions would be very

low for the following reasons. The radio frequencies used by the satellites would be in the

extremely high frequency (E H F) radio band and

would have a wavelength of order several millimeters. Because the wavelengths are so

small, EHF signals would be collimated into an

extremely tight beam by the 5-inch dish antenna. Only receivers in the path of the beam

could receive the transmissions from the submarine. Since the dish antenna would also be

highly directional for receiving satellite

signals, it would be effectively impossible to

jam incoming signals from the satellite.

The satellites could be survivable against

satellite attacks. The high-orbit satellites could

be put in five times geosynchronous orbits

(almost halfway to the Moon) and would be

very difficuIt to attack, even using large space

boosters.

Earth-launched interceptors would take 16

to 18 hours to reach the satellites, During this

period, the satellites could be maneuvered

while they are out of sight of Soviet groundtracking stations, forcing the space boosters to

make course changes beyond their propuIsive

endurance. If there was an extended period of

conflict and the United States did not want to

keep repositioning these satellites, the groundtracking stations could be destroyed and the

satellites could be repositioned for a final

t i me.

Submarine Navigation and Mapping

Needed for High Missile Accuracy

In order to have high missile accuracy, the

missile guidance system must have accurate

information on the missile’s initial velocity,

position, and orientation immediately prior to

launch. This information can be obtained from

navigation systems on the submarine and from

gravity maps of the submarine operating areas.

These systems will be briefly described here

and will be discussed again in detail in the

section on missile accuracy.

The submarines would maintain accurate information on their position using an advanced

submarine inertial navigation system ESGM/

SINS. They could also measure their velocity

very accurately using a VMS. This information

would be fed to the missile guidance system

prior to launch so that errors in missile accuracy due to velocity and position uncertainties would be minimal.
Ch. 5—Small Submarine Basing of MX 175

ESCM/SINS could be reset by making navigational fixes on the GPS. If the satellites were

destroyed by enemy action, the navigation

system could instead be updated using any of

150 covert acoustic transponder fields.

The acoustic transponder fields would be

layed by submarines while on normal patrols.

Typically, such operations would take several

hours. After laying a transponder field, the submarine would determine transponder positions

using the ESGM/SINS or the GPS. The transponder field couId be turned on using an encrypted acoustic signal that could be sent from

the submarine or by a small, powered, underwater drone deployed by the submarine, Small

boats could later use an encrypted acoustic

signal to command the transponders to release

their anchors and float to the surface for

retrieval. In this way, the transponder fields

could be constantly shifted if the need arose.

Orientational information for the missile

guidance system would be obtained with the

aid of gravity maps of submarine operating

areas. These maps would be generated using

satelIites, surface ships, and possibly submarines to measure gravity anomalies near the

surface of the ocean and in space.

Missile Guidance Technologies

There are three sets of missile guidance

technologies that could be used to maintain

high accuracy from sea. These are:

1. pure inertial guidance,

2. star-tracker-aided inertial guidance, and

3, radio-aided inertial guidance.

The strengths and weaknesses of these systems will be described in more detail in the

section on missile accuracy.

Pure inertial guidance would essentially be

similar to that of the land-based missile, with

some of the methods of performing missile

guidance calculations modified for sea basing.

Star-tracker-aided inertial guidance would

be similar to that of the land-based system but

with the aid of a star tracker to help correct for

position, velocity and orientational guidance

errors that accumulate during missile flight.

These corrections are done by sighting on a

star and comparing the star’s measured position to that of its expected position. The Trident I missile uses a star tracker and experience with this missile has demonstrated that

this technology is very reliable and effective as

a means of obtaining high accuracy with seabased missiles.

Radio-aided inertial guidance depends on

radio beacons to correct for position, velocity,

and orientational guidance errors that occur in

missile flight. These corrections are done by

sighting on a system of radio beacons.

The system of radio beacons used by the

missile could be either on satellites (the GPS)

or on the surface of the Earth (such a system

has been called a Ground Beacon System

(CBS) or an Inverted Global Positioning System

(IGPS)

If a submarine-based system used radioaided inertial guidance as a means of maintaining high accuracy, a GPS guidance fix

could be taken by missiles launched anywhere

within the deployment area. I n the event of

outage of the GPS, which could occur if the

satellites were attacked, the secondary landbased IGPS could be used to maintain the

missiles’ accuracy. However, if the ground

radio beacons are used, the missiles might

have to be launched within 400 to 500 miles of

the ground beacons in order to get good

enough line of sight contact to maintain

missile accuracy.

The system of ground radio beacons could

be deployed along the coast of the continental

United States and Alaska. There would be a

large number of such beacons and a larger

number of decoys to make it costly for the

Soviets to attack the beacons.

If the GPS were destroyed, and a launch

order was issued, some submarines might not

be close enough to the continental United

States to use the radio ground beacons. If time

permitted, NCA could direct the remaining

submarines to redeploy to areas within the

coverage of the ground beacons or direct them

to any of 150 presurveyed acoustic trans-
176 ● MX Missile Basing

ponder sites in the open ocean. The subma- the missile does not have a star tracker). If

rines could obtain extremely accurate mea- there was not enough time to redeploy to

surements of both position and velocity at acoustic transponder fields, missiles could be

these presurveyed sites. Missile accuracies launched with position and velocity informaachieved from these transponder fields could tion from the ESGM/Sl NS and VMS submarine

be slightly degraded relative to that achievable systems. Under these conditions, missile acwith the aid of the radio beacons assuming curacy wouId be degraded stiII further.

that the missile was only inertialIy guided (i. e.,

VULNERABILITY

The vulnerability of the force of submarines

to Soviet countermeasures depends on the nature and capability of the weapons systems

that would be deployed, the strategy of their

application, and the amount of resources that

might be committed against the submarine

force.

Potential threats to the submarine force fall

into several broad categories:

1. barrage attack using nuclear weapons;

2. large area searches, followed by barrage

attack;

3. large area searches, followed by attacks

using surf ace ships or aircraft;

4. nuclear explosion generated giant waves

(Van Dorn Effect); and

5. trailing of the submarine force, followed

by simultaneous attacks on all the submarines.

A barrage attack is a pattern bombing attack, using nuclear weapons. In its simplest

form, it is a random pattern bombing of ocean

areas in which the Soviets suspect submarines

are operating.

A variation of the barrage attack is an area

search followed by a barrage attack. If a n

adversary possessed a search technology that

was only able to locate submarines approximately over an extended period of time, then

only those areas of ocean in which the approximate locations of submarines were known

would be attacked. if the area in which the

submarines are localized was small enough, it

is possible that the barrage could result in the

destruction of the submarine force.

If an adversary possessed still better search

technologies, capable of localizing submarines

well enough to send out surface ships or planes

to attack the submarines, it would be possible

to sink the entire force of submarines with conventional weapons or a very small number of

nuclear weapons.

Still another way that a force of submarines

might be attacked is to detonate large nuclear

weapons in sufficiently deep water to generate

gigantic waves, If the waves were large enough

and the water shallow enough the waves might

tumble the submarines, causing sufficient

damage to sink them or render them inoperable. The phenomenon associated with the

generation of such large waves with nuclear

explosions is called the Van Dorn Effect.

If an adversary’s ability to search large areas

rapidly was inadequate for attacking the force

by limited barrage or with surface ships or

planes, he might instead choose to trail all the

submarines. once a significant fraction of the

submarines were under trail, they could then

be attacked at a prearranged time, resulting in

the destruction of the submarines and their

missiIes,

A barrage attack against the entire operating

area would require more than 30,000 high-yield

nuclear weapons. If the high-yield warheads on

the missiles were replaced with a larger number of smaller warheads (i.e., if the adversary

fractionated his force) the area of ocean that

could be barraged would be no greater.

If the adversary instead chose to generate

gigantic waves by detonating large nuclear
Ch. 5—Small Submarine Basing 01 MX ● 177

weapons in deep ocean waters, the submarines

would not be damaged unless they were in certain shallow water areas on the Continental

Shelf.

All other means of attacking the force of

submarines depend on an ability to detect and

localize, or trail, submarines with varying

degrees of success. Table 21 lists possible

observable that in principle accompany the

presence or operation of a submarine, Sensing

technologies that could potentially detect the

presence of the observable listed in table 21

are Iisted in tables 22 and 23. These technologies were examined as possible methods for

detecting and localizing a fleet of slowly

patrolling dispersed ballistic missile submarines. All these technologies were found to fall

into one of two broad categories: sensing technologies that do not appear to offer any possibility of detecting submarines effectively

enough to be able to threaten the submarine

force by area search or trailing; and sensing

technologies that could be spoofed, confused,

or rendered useless with inexpensive and easy

to implement countermeasures.

Tactical and Strategic Applications of

Ant i submarine Technologies

it should be noted that many sensing technologies of great use in tactical antisubmarine

operations are of Iittle use in the strategic role.

Table 21 .—Submarine Observable

Acoustic radiated sound

Acoustic reflected sound

Heat (infrared signatures, surface scars from snorkeling

submarines, hydrodynamic transport of reactor heat to

ocean surface)

Electromagnetic disturbances

Ocean surface effects (Bernoulli hump, snorkel or

periscope wake, trailing wire wakes, microwave

reflectivity of the ocean surface)

Hydrodynamic wake effects (salinity, temperature,

conductivity, density, etc.)

Erosion and corrosion products

Chemical Effluents

Irradiated elements in sea water

Magnetic field disturbances

Optical reflectivity (blue-green lasers)

Luminescence

Biological disturbances of marine life

Table 22.—Acoustic Sensors for

Submarine Detection

Submarine sonar systems

Active sonars

Passive sonars

Conformal arrays

Hull-mounted arrays

Towed arrays

Fixed array networks

Passive (sonobuoys and arrays)

Surface ship sonars

Active

Standard ship sonars

Semiactive

High-power low-frequency transmitters in combination

with long-towed arrays

Passive

Hull-mounted arrays

Towed arrays

Plane, ship, or helicopter deployed sonobuoys

Active

Semiactive

Sound source plus receivers

Passive

Helicopter sonars

Dipping sonars

SOURCE Office of Technology Assessment

Table 23.—Nonacoustic Sensors for

Submarine Detection

Infrared systems

Snorkeling scars

Reactor heat

Optical systems

Visual observations

Snorkles or masts

Wakes

Near surface effects

Blue-green laser

Synthetic aperture and pulse compression radars

Surface roughness

Snorkels or antennas

Hydrodynamic wakes

Bernoulli hump

Sniffing devices

Snorkeling effluents

Magnetic anomaly detectors

Passive microwave radiometers

Surface roughness

Hydrodynamic wakes

Electromagnetic detectors

Turbulence sensing systems

Trace element detectors

Activation product detectors

SOURCE Office of Technology Assessment

SOURCE Office of Technology Assessment
178 ● MX Missile Basing

For example, an attack submarine that is moving at high speed in order to position itself to

attack a battlegroup or convoy may be making

tens or hundreds of times more noise than that

made by a slow-moving balIistic missile submarine. The close proximity of the fast-moving

hostile submarine and the large amounts of

noise associated with highspeed operations

makes the attack submarine susceptible to

detection by the battlegroup. If the attack submarine is detected by a passive sonar and it is

not possible for the sonar operator to determine the range of the submarine from the battlegroup, a plane or helicopter equipped with a

magnetic anomaly detector could be sent out

along the direction of the sonar contact to

localize the submarine. The aggressive tactics

required of the attack submarine result in the

submarine increasing its detectability while

simuItaneously bringing itself within close

range of potential adversaries. This circumstance is completely different from that of

the balIistic missiIe submarine.

Theory of Open Ocean Barrage

A barrage attack is a pattern bombing attack, using nuclear weapons, of ocean areas in

which the Soviets suspect submarines to be

operating. I n the absence of information on

the locations of submarines, they would have

to barrage millions of square miles of suspected operating area. It is also possible that

the Soviets would attempt to gain information

on the approximate whereabouts of submarines by using large area search techniques. If,

for instance, each submarine in the force

could be contacted and localized once a day,

during the process of a large area search, then

the approximate locations of the submarines

would be known within a 24-hour saiIing distance of those contact points.

Figure 71 illustrates just such a circumstance. This diagram illustrates the results of a

postulated large area search in the Gulf of

Alaska that results in the observation and localization of four submarines in a period of 2

days. Upon observing a submarine, the search

aircraft notes its location and continues on its

search pattern. The submarine is assumed to

be patrolling at 5 knots and may be moving in

any direction from the point of contact. The

resuIt is that the submarine’s location is known

with less and less certainty as the submarine

continues its patrol. I n the diagram, the area of

uncertainty associated with the most recently

observed submarine is represented by a point.

The smallest circle represents the area of uncertainty generated by a submarine observed

10 hours earlier. The next larger circle illustrates the area of uncertainty of a submarine observed the day before and the largest

circIe represents the area of uncertainty associated with a submarine observed 2 days

before.

The ability to perform such large area

searches is based on considerably more than

just the dedication of military assets, A technology must exist that gives a sufficiently high

search rate so that the mean time between submarine localizations is smalI relative to the

time needed for the submarine to generate an

area of uncertainty sufficiently large to be impossible to barrage. For example, if a search

technology existed that, on the average, was

able to localize every submarine i n the force

every 24 hours, then each submarine would on

the average be be localized within a circle of

radius 120 miles (see fig. 71 for an illustration

of the size of the l-day area of uncertainty

generated by a submarine assumed to patrol at

an average speed of advance of 5 knots). The

submarine would, on the average, be known to

be somewhere within a circle of area 45,000

nmi 2. If the kill radius of a nuclear weapon is

of order 5 nmi, then 500 to 600 weapons would

be required to assure that the submarine was

destroyed.

Of equal importance to large area search

capability is a low false alarm rate. If one false

alarm were generated per hundred thousand

square miles searched, there would be 20 to 30

additional targets that would have to be attacked that were not submarines (assuming the

deployment area was of order 2 million to 3

million mi2

). If the average submarine contact

rate were stiII every 24 hours but there were, in

addition, 20 to 30 false alarms among the targets, 10,000 to 15,000 nuclear weapons would
Ch. 5—Small Submarine Basing of MX ● 179

Figure 71 .—Number of Weapons Required to Destroy Submarines That Have Been

Sighted Prior to a Preemptive Attack

Four submarines seen in two days

Speed - 5 knots

Kill radius per weapon - 3.5 nmi

Time since last observation

Just observed -1 RV

10 hr, 7,800 nmi2

, 196 RVS

1 day, 45,000 nmi2

, 1,130 RVS

2 days, 181,000 nmi2

, 4,500 RVS

SOURCE: Office of Technology Assessment

be required to cover the false alarms. Thus, the

false alarm rate must be very small or it will be

difficult to narrow down the number of targets

to a manageable level.

Finally of significance in the barrage attack

is the number of warheads available to the

adversary for purposes of barrage. If the

number of weapons grows to a large enough

number, it may be necessary to expand the

submarine operating areas or create decoys to

increase the number of false targets observed

in an area search. For conceptual purposes, an

approximate rule of thumb would be 20,000 to

25,000 nuclear weapons are required to barrage a million square miles of deep ocean

operating area. I n shallow water, the kill radius

associated with the underwater detonation of

a nuclear weapon is considerably smaller than

that in deep water. There is between 70,000

and 90,000 mi2 of Continental Shelf area (excluding the Continental Shelf of the Gulf of

Mexico but including the shelf area of the Gulf

of Alaska) available for submarine operations;

a pattern bombing attack of these areas wouId

require between 25,000 and 30,000 nuclear

weapons because of the smaller kilI radius.

Open Ocean Barrage With No

Information About Submarine

Locations

The submarines would operate in an area of

ocean sufficiently large so that a significant

fraction of them could not be damaged by pattern bombing with nuclear weapons. The deployment areas near the east and west coasts

of the United States and the Gulf of Alaska are

shown in figure 72. The outer boundaries in the

figure are 1,000- and 1,500-nmi arcs from Narrgansett Bay, R. I., Anchorage, Alaska, San
180 ● MX Missile Basing

Figure 72.—Potential Deployment Area Given 1,000- and l,500mmi Operating Ranges

‘-”-” “-”-”-’ -

SOURCE: Office of Technology Assessment.

Diego, Cal if., and the Miller Peninsula, Wash.

The exact boundaries of this area could vary

significantly with choice of base siting and

operational procedures. The operational area

wouId be of the order of 2 milIion to 31/2 milI ion miles.

In testimony given to Congress, Garwin and

Drell have suggested that a strategic nuclear

weapon detonated at the proper depth in deep

water might destroy a submarine at a distance

of 5 miles. According to this estimate, an

underwater nuclear detonation could destroy

submarines within an area of ocean of about

75 mi2

.

Garwin and Drell have also stated that this

damage range could be considerably smaller if

the submarine were operating at a shallow

depth. If an open ocean barrage were attempted, a large number of missile launches

would be observed on early warning sensors.

The submarines could be ordered via the VLF

radio I ink to move to shallow depths where the

effects of underwater nuclear explosions

wouId be much shorter range. If this moveoperating

range

ment were to occur, the effectiveness of the

barrage would be substantially reduced relative to the numbers quoted in the paragraph

above.

Assuming the Soviets could deliver as many

ICBM warheads against MX-carrying submarines as they could against a land-based MX

system (i. e., 2,300 warheads) and the submarine damage range is 5 nmi, submarines operating with i n an area of 200,000 miIes of ocean

could be destroyed or rendered inoperable by

a nuclear barrage attack. This attack would

result in the loss of two to three submarines

and their missiles if the submarine operating

area was Iimited to only 3 m i I I ion m i 2.

Open Ocean Barrage After Detection of

Snorkeling Submarines

If a sensing technology with a very high

search rate and a very low false alarm rate

were available, it is conceivable that submarines could be contacted often enough that

the entire operating area would not have to be
Ch. 5—Sma/l Submarine Basing of MX 181

barraged in order to sink the submarines.

Assume a search technology capable of detecting submarines only when they are snorkeling. This device could be a passive sonar

detecting the diesel engine tonals or an airborne radar detecting a snorkel mast. If 50 submarines were uniformly dispersed within 3

mill ion mi2 of ocean, one submarine could be

expected in every 60,000 nmi2

.

Figure 73 illustrates the concept of a large

area search as it would apply to an aircraft

searching for snorkeling submarines, since the

sonar ship would be unlikely to detect a submarine operating on batteries. The same diagram could apply to a sonar ship. Although the

sonar ship would move more slowly than an

aircraft, it is possible that its detection range

wouId be greater. The resuIt might be that both

the sonar ship and the aircraft could have the

same search rate. As illustrated, if the search

platform passes within detection range of a

submarine, the submarine may not be snorkeling and wouId therefore not be detected.

Also worthy of note is that the submarine

could have the ability to counterdetect the

search platform before the search platform is

close enough to detect the submarine. This discovery could occur if the search platform is a

fast-moving surface ship (that makes a lot of

noise) or a radar plane (that emits a signal that

is detectable at a greater distance than the

signal reflected from the snorkel).

In order to develop a more quantitative picture of the possible outcome of a determined

large area search effort, the following assumptions are made about a large area search effort:

1. a search technique is available that can

search 14,000 nmi2 per hour, This method

might be an aircraft that flies at 350 knots

and can observe snorkels at 20 nmi on

either side of its flight track or a long

range sonar system that is towed at 14

knots and can detect snorkeling tonals at

500 nm i in each direction;

2. submarines snorkel 10 percent of the

time;

Figure 73.—Large Area Search With Technology

That Can Only Detect Snorkeling Submarines

SOURCE: Office of Technology Assessment

3. the probability of detecting a submarine

when it is in range is 50 percent;

4. the number of false detections is infinitesimal relative to the number of

valid detections, even though extremely

large regions of ocean are being searched

rapidly; and

5. there are 100 units searching the 3-millionnmi deployment area 24 hours per day

365 days per year.

These assumptions lead to a detection rate of

one submarine every hour by the 100 searching

units in the 3-milIion-nmi2 deployment area.

If the position of each of these submarines

was recorded, then 1 hour after being detected

a submarine couId be anywhere within a 5-mile

radius of its original position. At 2 hours the

distance will have grown to 10 miles, at 3 hours

15 miIes, and so on.

The Soviet Union could then pattern bomb

each area determined by the patrol radius of a

previously sighted submarine. If nuclear weapons with kill radius of 5 miles were used, one
182 ● MX Missile Basing

weapon would be needed to guarantee the destruction of the submarine seen 1 hour earlier,

four weapons would be needed for the one

seen 2 hours earlier, nine for the one seen 3

hours earlier, sixteen for 4 hours, and so on. To

destroy 20 submarines, 2,870 weapons would

be needed, 5,525 would be needed to destroy

25 submarines and 9,455 weapons would be

needed to destroy 30 submarines.

It should be noted that passive sonars would

not be able to localize submarines at such

great distances since fluctuations in sound

transmission in the ocean make measuring distances impossible. Cross fixing with multiple

units would almost never occur because of

fluctuations in the acoustic transmission of

sound in the ocean. It would be a common circumstance that the sound would reach one of

the sonar units, but not the other.

If the units were aircraft searching with

radar, they wouId have to make long transits in

order to remain on station. The aircraft would

have to transit from bases to the submarine

deployment areas, search the areas, transit

back home, and be refueled and repaired for

the next transit out. In order to maintain one

aircraft on station continuously, three to six

aircraft would be needed. Some typical base

loss factors (i. e., the number of platforms

needed per platform continuously on station)

are shown in table 24 for turboprop aircraft

transiting from Soviet bases to operating areas.

Finally, it is absolutely necessary that false

alarm rates be extremely low in spite of the

fact that vast areas of ocean must be searched

at a very high rate. As will be illustrated in the

discussion to follow, even low or moderate

false alarm rates would render the most effective area search useless.

Searches With Technologies That

Observe Non snorkeling Submarines

It is conceivable that a search could be performed using a technology that was able to

detect the presence of a submarine whether or

not it is snorkeling. Such technologies might involve the use of active acoustic technologies

or magnetic anomaly detectors. The nature of

these technologies is that they are short range.

For purposes of discussion it will be arbitrarily

assumed that the detection range of these

technologies would be about 5 miles. This

assumption should not be taken as a true estimate of capabilities since that would depend

on the acoustic properties of ocean areas,

magnetic storms, sensitivity of sensors, properties of the target submarine, etc.

Since the sensors being discussed in this case

do not require the submarine to be snorkeling

to be detected, all submarines within the

detection range of the sensor could be assumed to be detected. If it is assumed that an

aircraft must travel more slowly for magnetic

Table 24.—Operational Factors Affecting Radar Search

of Submarine Deployment Areasa

Operating area or Soviet naval Distance Time on station Transiting

naval facility or air base (nmi) (hours)b time (hours)c

Norfolk Murmansk 4300 Not possible —

Norfolk Cuba 870 6.6 4.1

Charleston Murmansk 4600 Not possible —

Charleston Cuba 610 7.2 2.9

San Diego Petropavlosk 3600 0.2 16.9

Seattle Petropavlosk 2800 2.1 13.2

Northwest Cuba 1400 5.4 6.6

Atlantic

Northeast Anadyr 2300 3.3 10.8

Pacific

aTlrne on station and Iratlsll assumes BEAR bomber configured for long-range Surveillance.

b~lgh altitude transit followed by low altitude search

CTrarlSl! speed Of 425 knots Tran.slt times Include transit 10 search area and transl! back to base.

SOURCE. Off Ice of Technology Assessment
Ch. 5—Small Submarine Basing of MX . 183

detection (say 100 knots) then it would be able

to detect every submarine within a 5-mile

radius of it as it moves along, This assumption

means the aircraft could search a 1,000 nmi

area each hour it is operating (assuming a

probability of detection of one when a submarine is encountered), I n order to achieve the

same detection rate that the aircraft in the

earIier exampl e achieved, 7 platforms

equipped with magnetic anomaly detectors

would have to be substituted for each of the

radar aircraft. Thus, it would require 700 aircraft on station continuously, which means a

fleet of 2,100 to 4,200 aircraft dedicated only

to search of the deployment area. If weather

did not interfere with the search and submarines did not take advantage of surveiIlance

data supplied through VLF channels to avoid

search platforms, then 5,525 warheads might

be needed in addition to these forces in order

to destroy half of the postulated force of 50

submarines.

Active acoustic search might be substituted

for passive. Since the range assumed is 5 miles,

and ships might travel at only 20 knots, it

wouId require 35 ships to replace every radar

plane in the first example (assuming a probability of detection of one if a submarine is

within the detection range)

A serious problem associated with active

acoustic search would be the problem of false

targets. Simply stated, a false target is an underwater phenomenon that generates a sonar

signal similar to that of a submarine. The existence of false targets generates an additional

complexity in the large area search problem

that can catastrophically degrade the effectiveness of the search effort:

1. nonsubmarine targets may be incorrectly

identified and tracked as possible submarine targets, and

2. submarine targets may be incorrectly

identified as nonsubmarine targets,

Figure 74 illustrates the circumstance of an

active acoustic search, The surface ship has a

sound transducer that emits sound that scatters off objects in the water. Unfortunately for

the searcher, sound not only bounces off the

submarine, but it also bounces off temperature

boundaries in the water, bubbles, plankton,

Figure 74.—Sources of Reverberation That Limit the Capability of

High-Powered Active Sonars

SOURCE: Office of Technology Assessment.
184 MX Missile Basing

schools of fish, the ocean bottom, and the

ocean surface. 1 n particular, the sound that

reflects back and forth between the surface

and the bottom of the ocean resuIts in an extended and very intense echo. Since the surface area of the ocean floor and ocean surface

are so great relative to the surface area

presented by a submarine target, the initial

sound impuulse of the sonar returns Iike the

deafening echo from the walls of a cavern

From the point of view of the sonar operator,

each sound pulse is reflected by a myriad of

false targets and deafening echoes from the

“walls” of the ocean, From this set of confused

data, sound reflected from the hull of a submarine must be identified from sound reflected

from other “false targets” that could potential I y be submarines.

Figure 75 is a chart of the number of whale

targets over 30 ft in length per 1,000 nmi that

could potential Iy be mistaken for sonar targets

in the Western North Atlantic during the

month of September, Of all biological targets

in the ocean, whales are the most difficult to

distinguish from submarines on sonar. These

marine animals resemble submarines in size,

speed, acoustic characteristics, and certain

modes of behavior. When two or more whales

occur together, as they frequently do, they

represent a very significant sonar target, Under

normal conditions whales swim at 4 to 8 knots,

welI within the range of submarine patrol

speeds, and may fIee from manor naturaI”

predator-s at speeds of more than 20 knots I n

addition to returning submarine like sonar

echoes, the power-fuItaiI flukes of whales prod u ce swimming sounds that resembIe the

screw ( i e , propelIer) noise of a submarine

Smaller fish can also have very large sonar

cross sections because they have air-filled

swim bladders that intensely reflect sound.

When these fish collect into schools, they can

present very convincing submarine-like sonar

signaIs.

If the submarine is moving, the reflected

sound from the hull will be slightly shifted in

frequency relative to sound reflected from stationary objects in the water. The frequency

shifted sound might be separable from other

sounds provided the submarine didn’t slow

down to reduce the the size of the frequency

shift. If the sonar platform speeded up in order

to get a higher search rate, the sound reflected

from the “walls” of the ocean would be shifted

in frequency. This would make it very difficult

t. separate the frequency shifted “echo” from

reaI signals generated by moving targets.

If a submarine counterdetected an adversary performing an active acoustic search, the

submarine could also turn toward or away

from the source in order to reduce the amount

of reflected sound from the hull. The sound

refIection wouId be reduced because the intensity of sound reflected back toward the sound

source would be roughly proportional to the

cross sectional area the submarine presents to

the source. Since the cross sectional area

wouId be reduced by about a factor of 10, the

sound refIected back to the acoustic searcher

wouId also be reduced by a factor of 10 I n add it ion, since the f rent or back of the submarine

has a more highly curved surface than the side,

sound wilI be more diffusely reflected from the

front or back of the submarine then it would

be if it were reflected from the side. This same

principle of reducing detectability by causing

refIections to be diffuse is a I so of use in lowering the radar cross sections of aircraft.

Thus, there are many problems of both a

technical and operational nature that seriously

hamper active acoustic technologies as a

means of searching out submarines.

Increased Range Acoustic

Technologies

There are basically two ways that acoustic

search technologies might in principle be

made more efficient for long-range searches

for submarines. One way would be to increase

the sensitivity of passive acoustics, the other

wouId be to increase the power of active

acoustics.

Unfortunately, the more power that active

acoustics puts into the water, the more sound

reverberates through the ocean blinding the

abiIity of the acoustic system to the smalI

signals from a submarine. Active acoustics can
Ch. 5—Small Submarine Basing of MX ● 185

Figure — Potential Whale Sonar Targets (Western North Atlantic)

500

---6- No data available

I

I

I

300

200

,

--

90° 80° 70°

+

60°

I

50°

SOURCE Oceanographic Off Ice, U S Navy
186 ● MX Missile Basing

be very effective against submarines at short

range, simply because the signal from a nearby

submarine is so much more intense than background signals. However, as the submarine

moves away from the active sonar, its intensity

will drop at least with the fourth power of

range. Thus, if the submarine is twice as far

away, the signal from it wilI be 16 times weaker

(24 = 16*). The background reflections from the

ocean surface and bottom will not change.

Hence, it becomes more and more difficult to

distinguish reflections from the hull of the submarine from the unwanted ocean reverberations. Increasing the power of the sonar only

increases the unwanted reverberation along

with the wanted signal, Thus, the nature of

sound propagation in the ocean presents a fundamental limit to the increased capability of

active acoustics.

Passive acoustics has similar barriers to increased performance. Passive acoustic sonars

must discriminate the sound of a submarine

from all the other sounds in the ocean. The

total radiated acoustic power of some foreign

modern submarines is measured in milliwatts.

In a calm sea, the sound from one of these submarines at 100 yd would be equal to that of

ocean wave and shipping background. No matter how one improves the quality of detectors

and signal processing, the quietness of modern

submarines and the noisiness of the ocean set

fundamental barriers on the capability of longrange sonars against slowly patroning submarines,

* The fourth power law comes about as follows Sound emmitted from the sonar source and sound refIected from the submarine on the average spread sphericaly at short range The Intensity of a sound wave that spreads sphericaIIy frorn a source

point WiII decrease as the square of the distance from that point

The intensity of found that ultimately arrive back at the search

platform i S first diminshed by a factor of distance squared

before reaching the submarine, and then diminished by another

factor of distance squared after it iS reflected by the hull of the

submarine Thus, as the distance between the submarine and the the

search platform Inc reases, the lntensity of the signal that

uItimately arrives back at the search platform diminishes at least

as fast as the fourth power of that distance. If the effects of

sound absorption are also include, the intensity of the signal

received from the submarine will decreased even faster

fourth power law as the distance between submarine and search

platform increases

Increased Radar Search

Using Satellites

Since large area search against snorkeling

submarines is likely to be Iimited by the endurance of aircraft and range of radars, it is

conceivable that other more exotic platforms

could be used for large area search. A highresolution radar (i. e., synthetic aperture radar)

has been flown on a satellite (Seasat-A had an

L-band (25-cm wavelength) synthetic aperture

radar) that has obtained a resolution of 25 m

from altitudes of order 500 nmi. In principle,

significantly higher resolutions are possible.

Seasat was able to observe ships on the surface

of the ocean with sufficient accuracy that

image processing could resuIt in crude identification of ship characteristics. Seasat was ,

under certain conditions, also able to observe

the hydrodynamic wakes of ships and the surface roughness of the ocean. Remarkable pictures of internal ocean waves, that impress

themselves through hydrodynamic coupling on

the roughness of the oceans surface, have been

observed from Seasat radar reflectivity data. It

is reasonable to expect that higher resolution

radars can and will be built that could be

capable of observing snorkeling submarines.

As an example of the surveillance capability

of a low resolution synthetic aperture radar

system, two photographs obtained through the

courtesy of M. L, Bryan of the Jet Propulsion

Laboratory staff are presented in figure 76

Photograph A was taken in the Bering Sea Test

as part of the Fisheries Imaging Radar Surveil

lance Test Program. This photograph wa’

taken using an airplane equipped with an L

band synthetic aperture radar. The small spot

on the lower left portion of the photograph are

smalI japanese fishing boats operating a purse

seiner (a large vertically suspended fishing net

and the larger bright spots are mother ships

Photograph B was taken on Seasat A orbi

1291. It is the area off Newport Beach an

Orange County in southern California. Th

white streaks in the photograph are probabl

ships. The bright and dark areas of ocean ar

due to the changing roughness of the ocea

surface and the angle of the radar return. Tlmulti ridged structures within some of th-

188 ● MX Missile Basing

bright regions are surface manifestations of

internal ocean waves that result in changes of

the surface roughness and the radar reflectivity.

A high-resolution radar system searching a

vast and constantly shifting ocean surface

could have a very high false alarm rate due to

random waves reflecting additional intensity,

In addition, the capability of the radar would

also vary dramatically with the sea state (i. e.,

size of waves and roughness of the ocean),

since the ocean surface creates an intense

background of reflected clutter that can be

very difficult to fiIter out.

The false target rate due to random wave

motion might be dramatically reduced by having the radar “repoint ” at the suspicious

target. However, such a radar would require

considerably greater amounts of signal processing in a technique already limited by signal

processing capabilities. Nevertheless, it is prudent to assume that signal processing and

radars could be sufficiently improved to

observe snorkeling submarines with a high

degree of confidence.

Figure 77 shows the ground track of a satelIilte that is at an altitude of 162 nmi and whose

orbit is inclined at 600 to the equator. This

orbit is similar to that used by the Soviet

Cosmos 954 radar satellite that entered the

upper atmosphere over Canada on January 24,

1978 (the actual orbital inclination of Cosmos

954 was 65 O). Note from the figure that the

satellite coverage is predictably intermittent.

[luring the 1.5-hour satellite period the ground

track advances 22.50 on the Earth below and

the search pattern shifts to the west (note the

orbits labeled one, two and three). After 16

cycles the satellite arrives over the same point

on the Earth’s surface but it will only have

Figure 77.—Ground Track of Radar Search Satellite

60° inclination

160-170 nmi altitude

1.5-1.6 hr period

SOURCE Off Ice of Technology Assessment
Ch. 5—Small Submarine Basing of MX ● 189

overfIown the deployment area on six or seven

orbits The satellite would spend about 4 to 5

minutes over the deployment area during each

of the six to seven orbits. Thus, one satelIite

spends no more than 25 to 35 minutes per day

over the deployment area. If two satelIites are

in the same orbit but separated in phase by

180 “, they would follow one another by 45

minutes (i e , by half of the 90-minute orbital

period) .Thus, for six or seven orbits a day, satelIites would be over the deployment area

once every 4S minutes Six to seven orbits

translates to 9 hours per day (six orbits times

1 5-hour orbital period) when satellites could

be expected overhead every 45 minutes If two

other planes of orbits with two satellites each

are staggered so they wilI not overlap the first

plane of two satellites, then eight satellites

would be required to cover the deployment

area 8 minutes every 90 minutes. Covering the

area for 16 minutes every 90 minutes wouId require 12 satellites and 32 minutes out of every

90 minutes would require 24 satellites. It

would thus appear that in order to cover the

deployment area 30 percent of the time, of

order 24 satelIites wouId be required.

If an eight-satellite constellation of radar

satellites was placed in orbit to cover the

deployment area, submarines could not snorkel for periods of longer than 40 minutes

before it would be necessary to secure snorkeling to hide from a satelIite. If 150 minutes of

snorkeling were needed every day, eight satellites would force the submarines to snorkel for

four periods of 40 minutes each and 16 satelIites would drive the submarines to eight or

nine periods of 18 minutes each. I f observation

by a constellation of eight radar satellites had

to be avoided, the normal 150 minutes continuous snorkeling period wouId have to be extended by 12 to 16 minutes due to the three to

four periods (of length 4 minutes each) the

satellites would be overhead. For 16 satellites

the period could be extended to 180 minutes

and for 32 satellites it could be extended to

more than 200 minutes. The submarines would

therefore have to be designed so they could

snorkel for many successive short intervals.

Current diesel-electric submarines may not be

capable of this type of operation (modern submarines may be able to interrupt snorkeling for

periods as short as the necessary 4-minute

periods without serious losses in snorkeling efficiency, but data on such procedures are not

currently available) The power management

system of the small submarine might therefore

have to be configured so that the submarines

could snorkel efficiently for short periods of

time interrupted by stilI shorter periods of battery operation. This approach would allow

them to avoid surveillance from a constellation of radar satelIites and would only marginally affect the overall length of the snorkeling period.

Countermeasures to Radar Satellites

If radar satelites were considered to be a

serious enough t h r-eat, Garwin and Drell have

suggested that the ocean couId be seeded w i t h

radar refIecting objects that would be indistinguishable from snorkels

If many false snorkel targets were deployed

in waters near the continental United States, it

could make it easier for Soviet diesel-electric

submarines to operate in U. S waters because

U.S. naval forces could have as much d if ficuIty distinguishing faIse snorkels as wouId the

radar satelIites. If the snorkels could not be

designed to be distinguishable to U.S. naval

forces, but not to space-based radars, such a

strategic countermeasure could disrupt our

own tactical operations.

Another possibility would be jamming the

radar satelIites from ground- or sea-based stations. However, jamming could have international implications. Since the intermittent

nature of the satellite orbits makes avoidance

of detection straightforward, neither of these

countermeasures would likely be preferable to

intermittent snorkeling.

War of Attrition

As mentioned in the introductory remarks to

this section, the strategy associated with a

given surveillance capability, coupled with

avaiIabIemilitary resources, couId affect the

outcome of a preemptive attack on the force

of submarines. It is therefore possible that the

surveillance capability postulated in the sec-
190 ● MX Missile Basing

tion on Open Ocean Barrage After Detection of

Snorkeling Submarines could be used to fight a

“war of attrition” rather than attacking in one

massive barrage. A “war of attrition” approach

to destroying the submarine force would simply involve immediate attacks on the submarines whenever a snorkeling submarine is

observed. The outcome of this type of attack

would be considerably different from the

method discussed earlier of constant surveillance followed by a massive barrage attack. The time period over which the attack

wouId take place wouId be days or weeks,

rather than fractions of an hour Nevertheless,

in order to assess the seriousness of such a

threat, it is useful to get a sense of that time

sca I e.

Let us assume that the Soviet Union is able

to keep 100 planes on station over a northwest

Atlantic operating area. This deployment

would require the commitment of a fIeet of

between 300 and 600 planes constantly flying

the 1,400 nmi transits to and from the operating bases in Cuba. Assume for simplicity that

all the submarines are operating in a 3-millionmi operating area in the Northwest Atlantic.

Then as estimated in the previous section, one

submarine should be observed every hour of

operation.

For purposes of discussion, assume that

each time a submarine is sighted it is attacked

and sunk, and continental based U.S. forces do

not react to this action at any point during the

process. It could then be expected that approximately half the force of 50 submarines would

be destroyed in the first day. Since there now

wouId be half as many submarines distributed

throughout the deployment area, the rate at

which submarines would be contacted and destroyed the next day would drop by two. This

wouId then result in half the surviving submarines (about 12 submarines) being destroyed

in the next day of operation. On the third day,

the rate of contacts would drop again by two

and only six submarines would be left. This

kind of circumstance is called a “war of attrit ion” and was very successful against submarines in the North Atlantic during World

War I 1.

Another possibility is that a submarine is

observed once every hour but only ha If the

time the attack on the submarine results in its

destruction. Then one fourth of the submarines are destroyed the first day (about 12 submarines), another 9 are destroyed during the

second day’s operations, 7 the third day, 6 the

fourth day, 4 the fifth day, etc. Thus, 5 days of

operations resuIts in the destruction of 38 of

the 50 submarines as compared to the previous

example where 43 submarines were destroyed

in three days (it would take 7 days to destroy

43 submarines using the assumptions in the

current example).

The “war of attrition” scenario would require that the planes carry sufficient armaments to engage and sink submarines with a

high probability. It would also require that

large relatively defenseless surveillance craft

couId continuously transit the 1 ,400-miIe route

between Cuba and the submarine operating

areas, carrying out attacks on U. S, submarines

in airspace near the coast of the continental

United States, unopposed by American air and

sea forces Another assumption is that submarines could not, and would not, defend

themselves with the aid of decoys or underwater to air missiles,

Van Dorn Effect

The Van Dorn Effect is the creation of extremely high ocean waves over large areas of a

continental shelf by an appropriately placed

multi megaton nuclear detonation. The physical basis for the Van Dorn Effect is as follows

(see fig. 78). A wave created by an underwater

explosion in uniform, deep water wilI diverge

raidialIy untiI it moves into shallow water.

when the water becomes shallow enough the

wave energy is funneled into a smaller volume

01

: water and the wave height grows in height

relative to the height it wouId have had in deep

water. The shape of the Continental Shelf off

the eastern coast of the United States is sufficiently steep for an absolute increase in wave

height.

There is considerable uncertainty associated

with the generation of Van Dorn waves. The
Ch. 5—Small Submarine Basing of MX ● 191

Figure 78.— Van Dorn Effect

Continental shelf

Nuclear

explosion

SOURCE Office of Technology Assessment

curvature, steepness , and bottom characteristics (i e , sand or rock) of the continental

slope could effect the size and formation of

waves at different areas of the coast. The degree of underwater motion that submarines are

Iikely to be able to tolerate without losing their

abllity to launch missiles if also uncertain.

If a submarine were in sufficiently shallow

water, the water motion at the bottom of these

giant waves would make it unlikely that the

submarine wouId survive in good enough condition to be able to launch ballistic missiles If

the submarlne were operating off the Continental Shelf, the water wouId always be deep

enough that the Van Dorn Effect would not be

a threat The Van Dorn Effect is therefore not a

problem for submarines operating off the Continental Shelf

Because the nuclear explosions would have

to be generated in sufficiently deep water to

generate Van Dorn waves in the shallow water,

there would be several hours’ warning before

the arrival of these waves It any submarines

were operating in water too shallow to escape

the effect, and a Van Dorn attack were diagnosed quickly, several hours would be available for NCA to decide to launch missiles

at risk.

Theory of Tra

It is conceivable that a c

Iing

etermined adversary couId review the method of continuous

surveillance followed by barrage and determine that the Iikelihood of success is small

The adversary might be particularly discouraged after a review of the diversity, effectiveness, and cost of countermeasures relative to

that of his search and destroy effort It might

therefore be concluded that an effort to continuously trail the submarine force might be

more Iikely to meet with success.

To successfully trail a submarine, it is

necessary to have a device capable of sensing

the submarine with sufficient effectiveness

that some estimate of the position of the submarine relative to that of the trailer can be

maintained. It is also necessary that the device

be difficult to spoof or jam and that it not be

susceptible to simple countermeasures.

There are very few observable associated

with the presence and operation of submarines

that can be used to detect and track them. The

most effective and reliable of these, like

magnetic anomaly detection, tend to be very

short range and cannot be operated too closely to a platform (like a surface ship or sub-
192 ● MX Missile Basing

marine) that has its own magnetic signature.

Longer range techniques (like sonar) tend to be

subject to the constantly changing acoustic

properties of the ocean. Acoustic trailing

operations are further complicated by the

possibility that the submarine could move into

sound ducts, channels, and shadow zones, as a

means of suddenly “disappearing” from the

view of the trailer. These ubiquitous sound

ducts, channels, and shadow zones are created

by in homogeneous ocean waters.

A final serious problem confronting the

trailer is the possibility the submarine will

deploy decoys, jammers, and/or spoofers to

further complicate the problems of the trailer.

Nevertheless, it is useful to examine some of

the possibilities of trailing as a threat to the

force of smalI submarines.

The problem of trailing the submarine force

can be broken into three major areas of

anaIysis:

1, initiating the trail,

2. maintaining the trail, and

3. destroying the submarine.

Once the submarine is within a few thousand

yards, it is assumed that it can be destroyed

with a probability of one with conventional

means. This extraordinarily optimistic assumption presumes that the submarine under attack

takes no evasive actions and uses no devices to

confuse homing torpedoes or other devices

and that the weapon used against the submarine is 100-percent reliable.

According to these assumptions, the success

or failure of the trailing operation would only

depend on the ability to establish trail, and the

ability to maintain trail for a long enough

period of time that a significant fraction of the

submarine force is on the average localized,

Two extreme cases are useful to examine in

order to understand the significance of an

ability to establish and to maintain trail as

separate elements of the traiIing problem:

1, The probability of establishing trail is one,

but the mean time a trail is held varies,

2. The probability of establishing a trail is

small, but the trail, once established, is

not broken for the remainder of the submarine’s at-sea period,

In case 1, for example, if the submarines

were always picked up successfuIly as they

egressed from port, then the average number

of submarines under trail wouId be equal to

the percentage of time each submarine was

held in trail during its patrol. For instance, if

the submarines had a 60-day at-sea patrol and

the trail could be maintained for a period of 10

clays, then one-sixth of the submarines would

be, on the average, under trail.

In case 2, the fraction of submarines successfully trailed is determined by the number

of submarines for which a traiI was successfully initiated. In this case, if a trail were successfulIy established on egress from port onesixth of the time, and maintained for the entire

at-sea period, then one-sixth of the fleet would

be under trail at all times,

If one combines case one and two, and

assumes that one-sixth of the submarines have

trails established on them as they egress from

port, and one-sixth of those submarines are

maintained on trail (because they are trailed

on the average for 10 days out of 60), then onethirty-sixth of the submarines (i. e., less than 3

percent) can be expected to be under continuous trail. It is clear that both the ability to

maintain traiI and the ability to establish traiI

are extremely important if there is to be any

possibility of maintaining contact with a signIficant fraction of the force,

A more complete analysis of the trailing

plroblem would include probabilities that trails

are established, broken, and reestablished. In

the assessment that includes the possibility

that a lost trail is reestablished, the possible

use of muItiple sonars and magnetic anomaly

detectors, surface ships using active and

passive sonar systems, etc., must also be included. In such a case, if the target submarine

is recontacted by a search unit other than the

trailing unit (perhaps by a helicopter) the probability that the search unit successfulIy hands

the contact back to the trailing unit (which

wouId have to be a ship or submarine i n order

to have endurance similar to the target) must
Ch. 5—Small Submarine Basing of MX ● 193

also be included in the analysis). Simulations

accounting for such complexity have been performed. The models are technically complex

and the results of the analysis are consistent

with conclusions drawn from insights gained

by examining cases 1 and 2. Since no new insights are gained with the additional complexity, and the models are mathematically

complex, these models will not be presented or

discussed here.

Establishment of Trail at Port Egress

In order to establish a trail, it is necessary to

know the whereabouts of the submarine within

a sufficiently small area of ocean that the submarine can be localized well enough to begin

trailing operations. As discussed in other sections, no technology has been identified that

appears to provide the ability to effectively

search large areas of ocean. Given this circumstance, the trailer would have to seriously

consider attempting to trail at port egress,

where submarines are initially localized, if

there is to be any hope of success.

The trailer would have to use either an

acoustic or nonacoustic sensing technology to

detect and follow the submarine. This sensing

technology would have to be both reliable and

difficult to counter. Since trailing operations

would have to be initiated at port egress,

where substantial U.S. assets would be available to help assure egress, the sensing technology would also have to be unjammable and

resistant to spoofing from electronically

equipped tugboats, submarines, or surface

combatants that might aid in the egress.

The trailing of one submarine by another

could be viewed as somewhat similar to the

trailing of a plane by a homing missile. The

homing missile would either have to passively

sense some observable of the aircraft Iike heat

from the engine, or actively illuminate the aircraft as with a radar. If the trailing missile is

heat-seeking, the aircraft can disperse flares

which the missile is unable to distinguish from

the aircrafts engines. If the missile is radarseeking, the aircraft can disperse chaff to

create false radar targets to confuse the radar.

Another measure could simply be to jam the

radar (which, depending on the radar, might

not be so simple). Still another measure would

be for the aircraft to dispense a self-powered

decoy that would retransmit the radar signal

from the trailing missile in a way that would

make the plane and the decoy indistinguishable to the radar. Such a device (called the

Quail) was deployed in limited numbers during

the 1960’s on B-52s as an aid for use in confusing Soviet radars.

Such ideas have been applied in naval warfare as well. During the Battle of the Atlantic,

the Germans deployed an acoustic horning torpedo called the Zaunkoning. The Allied

countermeasures was to have convoy escorts

stream noise emitting “Foxers” to create false

targets and jam the acoustic homing torpedo’s

sensing system.

If there were an attempt to trail a submarine

using passive sonar, for instance, trail could be

broken through the clever use of a “Foxer’’-like

device. Such an operation could be done as

follows: A submarine being trailed may deploy

a small device that makes a sound similar to

the submarine. As the submarine proceeds forward, the device could be slowly played out

behind the submarine, making it appear to the

trailer that the submarine is moving more slowIy than it actually is. The trailer would then

have to slow down in order to avoid risking a

collision, resulting in an increased distance

between the trailing and the trailed submarines. The device could also slowly increase

the intensity of the simulated submarine

sound, further convincing the trailer to increase his distance between him and his potential adversary. At the appropriate time, the Iine

could then be cut or the trailing device shut

off. The trailer would only know that the submarine had disappeared from sonar contact.

A most likely technology of use to a trailer

would be an active or passive sonar. Active

sonar at close range can be quite reliable

(remember the distance to the fourth power

signal to noise relation). A problem with active

sonar is that the trailer is more vulnerable to

attack than the trailed, since the sonar is

broadcasting its own position.
194 ● MX Missile Basing

Passive sonar is preferable to active since

the trailer does not make himself quite so

vulnerable to preemptive action or countermaneuvers. However, if the submarine is quiet

enough, it will be exceedingly difficult to trail

by passive means.

Figures 79 and 80 show another means of

making it difficult to establish trail against a

submarine using either active or passive sonar.

The submarine (or accompanying tugboats

from the port) could deploy small torpedo-like

devices (similar, in principle, to the radar confusing Quails deployed by B-52s). These devices could be equipped with smalI tape

recorders which simulate the sound of a submarine. EIectrical coiIs could simulate

magnetic and other signatures and a transponder mounted on the device could simulate

the reflection of sound from the hull of a submarine. If the need arose, devices like these

could not only be carried on submarines to aid

in breaking trails, but they could be deployed

in large numbers each time a submarine attempted egress from port. Devices deployed

from the port could be preprogrammed to

behave like submarines and could regularly be

recovered after each egress operation. Simple,

inexpensive, and recoverable devices could be

constructed using either battery or fuel cell

technology to simulate submarines egressing

from port. The fuel cell device could be programed to behave Iike a submarine using an inexpensive microprocessor and would have

great endurance. The device could be used to

deceive trailers for days, if an operational

need for such a capability arose. At some preprogrammed point it could turn around and

come back to port for recovery.

Still another possible device that could

prove useful against a trailer using active sonar

would be a device similar to the German pilIenwerfer. The pillenwerfer was a device used

by German U-boats during World War Il. The

U-boats could eject this device during the

course of an engagement and create a dense

underwater cloud of bubbles. Since sound

would be intensely reflected by the pillenwerfer bubble screen, active sonars could mistake the cloud for a submarine or could not

observe the submarine maneuvering behind

the screen to escape.

Attempting to establish trail on a submarine

egressing from a home port requires not only

Figure 79.—Active Acoustic Search for a Submarine That Has Dispensed Decoys

Which Simulate a Reflected Sonar Signal From a Submarine Hull

SOURCE: Office of Technology Assessment.
Ch. 5—Small Submarine Basing of MX ● 195

Figure 80.–Passive Acoustic Search for Submarine That Has Dispensed Decoys Which

Simulate the Sound of a Submarine

Noise from distant

ships, oil drilling,

earthquakes, fish,

rainstorms. ocean Noise reflected

SOURCE: Office of Technology Assessment

“spoof proof” sensing devices with sufficient

range and reliability for “a trailing operation,

but the technology must be difficult to jam.

Jamming, while not as elegant as the method

of decoys, is at least as effective a means of

“delousing” submarines as they egress from

port. This could be accomplished with small

surface ships or preemplaced sound projectors. If the trailers are using devices like

magnetic anomaly detectors, relatively modest-sized coil devices capable of distorting the

local magnetic field could be emplaced in the

egress region or towed by small ships. These

would, in effect, be magnetic jammers.

Still another tactic available for port egress

operations might be to use the 12-mile limit to

force the adversary to spread himself thin. The

submarines could proceed up or down the

coast well within territorial waters before proceeding into the open ocean. Since the submarine would be in noisy shallow coastal

waters, it would be undetectable from outside

the territorial limit. The adversary would virtually have to commit thousands of ships to attempt to establish trail on port egress.

Finally, the logistics of establishing a picket

in order to pick up egressing submarines

should not be neglected. Assets stationed outside a port in order to try and pick up egressing

submarines would have had to transit from

home ports. This would mean that each ship

would have to spend a period of time covering

the port access looking for egressing submarines, a period of time transiting back to

home ports for resupply and repair, and a

period of time transiting back again to cover

the port. Enough ships and/or submarines

would have to be committed at all times to the

port watch so that all the entrances, exits and

coastline which submarines could use for

egress operations from the port would be continuously covered. There must also be enough

excess ships or submarines on station so that

all suspicious contacts can be prosecuted until

they are determined to be false targets.
196 ● MX Missile Basing

It should be clear that egress from port has

such a rich diversity of countermeasures and

technologies that it can effectively be considered a nonexistent threat to any well-run

submarine force.

Establishment of Trail Using Large Area

Open Ocean Search

Since egress from port has such a variety of

operational countermeasures and technologies that favor the egressing submarine, an

adversary may instead choose to combine a

large area search with trailing vessels at sea.

Again, for purposes of illustration, it is

assumed that 300 to 600 long-range aircraft

equipped with radars that allow for a 14,000

nmi2 per hour search rate transit from Cuba to

a 3-million-nmi2 deployment area in the Northwest Atlantic. This fleet of aircraft would be

large enough to maintain 100 aircraft on station, 24 hours per day. Between transit and

search operations, these aircraft would consume more than 1.5 million gal of aviation fuel

per day. As postulated earlier, such a search

might produce a radar contact with 1 of the 50

assumed submarines on the average of once an

hour. This contact would occur when the submarine was snorkeling so the submarine would

have detected the radar signal and could be

presumed to recognize it had been sighted.

If the Soviets have, in addition, 1,000 ships

evenly distributed over the 3-mill ion-nmi 2

operating area, one ship will on the average be

able to patrol a 3,000-nmi2 area of approximately 30-nmi radius. Assuming the ship is, on

the average, capable of arriving at the area of

contact within 1 1/2 to 2 hours and the submarine has moved in a random direction at 10

knots after being detected, the ship will have

to search an area of 700 to 1,2oO nmi2 by the

time it arrives in the vicinity of the aircraft

radar contact. If the ship has sonar device with

a 2- or 3-mile range and can search at 10 knots,

it will be able to search about 40 to 60 nmi2

within the first hour of arrival at the location

where the submarine was first sighted. If the

submarine is not found within the first hour of

search, it will have traveled another 10 nmi

from the point of sighting and would be somewhere within an area of 2000 to 3,000 nmi2.

The probability of the ship picking up the

submarine would be of order 0.03 to 0.08 and

would vary dramatically with how fast the

ships arrive at the point of aircraft sighting.

Assuming that the probability of the ship establishing trail is 0.08, then on the average, 2 of

the 50 submarines would be picked up on trail

each day of operation.

If the submarine were equipped with 10

decoys, it could then attempt to break trail in

the following manner. If trail is established, a

single decoy could be released by the submarine, giving the trailer a one in two chance of

choosing the correct target. If the correct target is chosen, another decoy could be released. Thus, by the time the submarine had released its tenth decoy, the probability that trail

is maintained would be about one in a thousand (210 = 1,024).

There are many variations on the open

ocean search followed by trailing. These variations include the use of helicopters operating

from the on-station search ships and the use of

multiple ships converging on sighting locations. The assets that must be committed by an

adversary, under optimistic assumptions of

good weather and capable reliable sensors, is

enormous relative to countermeasures. I n the

above case, the 50 submarines equipped with

500 decoys are able to remain untrailed by an

adversary who has committed a fleet of 300 to

600 long-range surveillance aircraft, 1,000 surface ships, and sensors that surpass the performance capabilities of what is likely to be

achievable.

As is indicated throughout the discussion on

vuInerability, opportunities for obtaining

information on the location of snorkeling submarines are far greater because of the increased noise output associated with snorkeling and the fact that a snorkel mast is exposed

above the ocean’s surface. Detailed analysis

indicates that long-range passive detection of

modern snorkeling submarines would not be a

threat to the survivability of the force. Analysis

indicates that nonacoustic search techniques
Ch. 5—Small Submarine Basing of MX ● 197

that might be able to detect snorkels will also

not seriously affect the survivability of a fleet

of diesel-electric ballistic missile submarines

deployed within 1,000 to 1,500 nmi from the

continental United States and Alaska.

Nevertheless, as remote sensing improves

and satellite surveillance becomes more complete, it is possible that concern about the

need to snorkel could arise. It is therefore of

interest to describe some features of modern

diesel-electric propulsion systems and compare them to another proven propulsion technology — nuclear propulsion.

Diesel-Electric Propulsion Technology

The diesel-electric propulsion system in the

German-type 2000 powerplant is an example of

proven capabilities in modern nonnuclear submarines (see fig. 81). The submarine is designed

to snorkel using four 1,400 RPM high-speed

diesel-driven generators simultaneously. When

configured as an attack boat, it will snorkel

less than 90 minutes out of 24 hours (assuming

it snorkels with a 6-knot speed of advance and

patrols on batteries at 5 knots). If the submarine were configured as a strategic weapon

submarine instead, additional power would be

Figure 81 .—German Type 2000 Submarine

I

— .

Upper deck

2370 Metric Tons Displacement (Surf)

SOURCE: Office of Technology Assessment
 ● X Missile Basin g

consumed due to increased hydrodynamic

drag on the missile fairings and added load

due to the strategic weapon system and the

missiles. The snorkeling period with these additional loads would be about 2‘A hours per day

(i.e., the submarine would snorkel about 10

percent of the time). The submarine carries 960

batteries which are energy-managed by a microprocessor. The propulsion motor has a maximum output of 7,500 kW and is double mass

isolated from the hull for silencing. The motor

is air coupled to the shaft (for silencing) and

the shaft drives a seven-blade skewback propeller. When configured as an attack submarine, this boat has a top speed close to 25

knots (which can be maintained for about 1

hour).

When operating on batteries, any modern

diesel-electric submarine will, for all practical

purposes, be close to acoustically undetectable by passive means. Thus, the diesel-electric

technology demonstrated in the Type 2000

would easily fall within the assumed capabilities of the vulnerability discussion presented

earlier.

Nuclear Electric Propulsion

Small submarines that use nuclear propulsion might have survivability superior to those

powered by diesel-electric systems. * However,

this would depend on the nature of any unforeseen future threat that might emerge and is

therefore dissicult to analyze.

It is generally acknowledged that nuclearpowered submarines are noisier than dieselelectric submarines. If the acoustic outputs of

nuclear-propelled strategic submarines were

large enough to result in a threat to their survivability (and they are not), proven technol-

‘It IS hard to say that a coastally deployed, small strategic sub

marine would be more or less survivable if it were nuclear

powered since its survivability would not depend on an ability to

maintain high speeds for extended periods of time, as might be

the case with attack submarines In addition, since the coastally

deployed submarines would always be relatively near the continental United States, they would not have long transits to and

from patrol areas In any case, the survivability of either dieselelectric and the nuclear-powered units would be so high that the

choice of propulsion system need not be of serious concern

ogy exists that would permit them to be equally quiet.

Since the coastally deployed strategic submarine has modest power requirements relative to those needed by longer range faster and

more versatile submarines, it is possible to use

an inexpensive self-regulating TRIG A-type nuclear reactor as a power source alternative to

diesel-electric propulsion. The power system

would employ fully developed reactor technology used in conjunction with standard hardware and electronic components. Because of

the self-regulating features of this type of reactor (and, in fact, any small low enrichment

reactor), the safety and control systems on the

reactor would be very simple. The reactor

wouId be natural circulation and conversion to

electricity could be accomplished using thermoelectric modules (about 4 to 6 percent conversion efficiency is within proven technology). The reactor, with its shielding, would

weigh about 100 tons. Since the reactor would

generate electricity without the use of moving

parts (neither generators or pumps), the submarine would be as quiet as an electric-powered submarine and would never have to

snorkel.

The submarine could carry 550 tons of batteries as does the Type 2000 submarine since it

would need extra propulsion power on occasion. It would therefore have high-speed capability similar to the Type 2000 until the batteries were drawn down. Quick recharging

would be done with the aid of diesel-driven

generators. Since quick recharging would rarely be required under normal operating circumstances, the submarine would carry only

between 50 and 100 tons of diesel fuel.

The weight budget of the Type 2000 submarine indicates that a small submarine design of

this type is well within proven technology. The

Type 2000 carries close to 300 tons of fuel and

the modified TRIGA reactor weighs about 100

tons. Care would have to be taken in the submarine design to account for differences in

weight distribution dictated by a single large

component Iike a reactor.

A specific system design and the fabrication

of a prototype would be required before a
Ch. 5—Small Submarine Basing of MX ● 199

reactor unit could be brought into service. If

reactors were then produced at a rate of at

least six units per year, it would cost less than

$20 million (1981 dollars) per unit. This figure

wouId add only a marginal cost to the submarine.

If a decision were to be made to deploy MX

missiles on small submarines, such a propulsion system would clearly be a competitor with

diesel-electric propulsion, both in terms of survivability and cost. This deployment would

have to be considered by any design group

tasked with the problem of designing an MXcarrying system of small submarines.

Concluding Remarks on the

Vulnerability of Submarines

Antisubmarine warfare techniques and

methods is an area of high sensitivity due to

concerns about security. For this reason, the

numbers used in this section in conjunction

with specific search technologies should in no

way be construed as indicating the state of the

art with regard to the sensing technologies discussed. What this discussion has sought to do

is provide the reader with a sense of the richness, diversity, and complexity that accompanies both submarine technologies and operations. It should also be noted that all technologies that could in principle or in practice

be used as a means to find submarines have

not been discussed. However, the conclusions

that can be drawn about the survivability of

strategic submarines from the present discussion in fact vastly overstate the vulnerability

of these systems.

FACTORS AFFECTING THE ACCURACY OF

LAND- AND SEA-BASED MISSILES

In this section, some of the factors that play

a role in determining the accuracy of land- and

sea-based ballistic missiles are presented in

order to establish a context for discussion in

the sections that follow.

A ballistic missile is a device that is accelerated to a velocity sufficient to reach a

target or set of targets without further propulsion. Intercontinental range ballistic missiles

(missiles with a range of order 6,000 miles)

generally undergo powered flight for a period

of 5 to 10 minutes. Once powered flight is

complete, the missile’s upper stage and reentry

vehicles float toward a target, or a set of

targets, under the influence of gravity in the

near vacuum of space. In the final portion of

the flight, the reentry vehicles enter the upper

atmosphere and are subjected to very strong

aerodynamic forces before finally arriving at

targets.

During the initial stages of powered flight,

guidance errors can be introduced by uncertainties in the missile’s velocity, position, and

orientation. The effects of these uncertainties

can be understood if a comparison is drawn

between the different stages of the ballistic

missile’s fIight with those of the fIight of a rock

launched by a catapult. The powered phase of

the ballistic missile’s flight can be thought of

as similar to the action of catapuIting the rock

and the unpowered phase can be thought of as

the motion of a body in a gravitational field. In

the unpowered phase, the motion of the body

is entirely determined by the force of gravity.

Since the phase of powered flight is similar

to that of the catapulting of a rock, if the

missile is almost on course after the engines

have burned out, but the magnitude of its velocity is slightly in error, it will fall short or

long of the target (see fig. 82). If the missile

velocity is correct but the missile is slightly

misaligned from its intended direction, it will

also miss the target. In addition, even if the

missile is properly alined and has the correct

speed, if its launch point is moved with respect

to the target, the missile will again miss its

target.
200 MX Missile Basing

Figure 82.— Factors Affecting the Accuracy of a

Ballistic Missile

SOURCE: Office of Technology Assessment

The effects of uncertainties in the gravitational field also influence the missile’s accuracy in the early stages of powered flight.

When the missile is initially launched, the

forces that determine the motion of the missile

are due to the thrust of the rocket’s engines

and the gravitational field of the Earth (aerodynamic forces are neglected here for simplicity). If the gravitational field is not known

in detail, the missile will end up, after launch,

with a slightly different direction and velocity

than originally intended. Since this change occurs early in the missile’s flight, a slight

misalignment in direction, or uncertainty in

velocity, accumulates into a much larger

target miss as the missile floats for great

distances along its trajectory. As will be explained later in this section, these velocity and

direction errors can be introduced due to lack

of knowledge of the Earth’s gravitational field,

as well as due to imperfections in different

elements of the missile system. If unaccounted

for, these errors can accumulate into significant miss distances at the target.

After the missile’s engines are turned off, its

motion is determined by the gravitional field

of the Earth. If the gravitational field is different from that which is expected, the reentry

vehicle will not follow the trajectory that has

been planned for it. For this reason, the missile

guidance system must have data on the nature

of variations of the Earth’s gravitational field

along the trajectory to the target.

Still later in the missile’s flight, the reentry

vehicle enters the upper atmosphere and

begins to decelerate violently (this process

usually begins at about 100,000 ft for a warhead flown at intercontinental ranges), In this

stage of flight, wind and rain can have an effect on the reentry, as well as uneven ablation,

body wobble, or misalinement. Errors that occur in guidance during this stage of ballistic

missile flight are called “reentry errors. ”

Missile accuracy is generally defined in

terms of the circle of equal probability (also

called the circle error probable) or CEP. The

CEP is the radius of a circle that is drawn

around the target in which, on the average,

half of the reentry vehicles fired at the target

fall. There are two geometric contributions to

the CEP. The first is called the cross range or

track error. This error is a measure of the miss

distance perpendicular to the direction of the

missile’s motion at the target. The second geometric contribution to the CEP is the down

range or range error, that is the miss distance
Ch. 5—Small Submarine Basing of MX . 201

along the direction of the missile’s motion at

the target.

Table 25 shows the different contributions

to target miss for a missile which depends on

pure inertial guidance at a range of 5,500 nmi.

This table gives some indication of the importance of initial errors in position velocity, and

alignment in determining the missile’s CE P.

Each of these error components contributes to

the down range and cross range errors as the

square root of the sum of the squares (see fig.

83). The CEP is then 0.59 times the sum of the

down range and cross range errors.

The major factors that contribute to the accuracy performance of any inertially guided

intercontinental range ballistic missile (missiIes of nominal range of 6,000 nmi) can be

broken into the following categories:

1.

2.

3.

4.

uncertainties in the initial position, velocity, and orientation of the missile at launch,

boost phase guidance errors due to inertial

sensing errors, and inertial computational

errors,

thrust termination errors at the end of the

boost phase,

velocity errors imparted to reentry vehicles

during deployment by bus,

5.

6.

7.

gravity anomaly errors,

uncertainties in the position of targets (targeting errors), and

atmospheric reentry errors.

Although the magnitude and importance of

each of these factors in determining missile accuracy will vary (with missile design, missile

range, weather conditions over the target area,

and the quality of gravitational data over the

flight trajectory of the missile), all but two of

these factors are in principle the same for both

land- and sea-based missiles.

Factors 1 and 5 account for most of the

difference in accuracy of land- and sea-based

systems.

Since sea-based missiles are constantly in

motion, the missile must be provided with accurate information on its position, velocity,

and orientation. This necessity requires a

navigation system capable of providing information to the missile before it is launched. The

quality of this navigational data will affect the

performance of the missile.

The quality of gravitational data near the

launch points of land- and sea-based missiles

may differ. If this is the case, this too will affect the accuracy performance of the missile.

Table 25.—Miss Sensitivities to Initial Errors for ICBM Trajectories

Error Component Miss Sensitivities

Units Down Range Cross Range

Initial Down range m/m 1 0.0

Posit ion Cross range m/m 0.1 0.7

Error Vertical m/m 5.4 1.3

Initial Down range m/(cm/see) 40 9

Velocity Cross range m/(cm/see) 2 10

Error Vertical m/(cm/see) 22 6

Initial Level m/arcsec 46 21

Alignment Azimuth m/arcsec 6 24

“These values apply to a 5500 nmi minimum energy trajectory CEP = .59 (Down range error + cross range error),

SOURCE. “Guidance System Application of MX Basing Alternatives” by Major G B Green/SAMSO and L N Jenks/TRW

83-477 0 - 81 - 14
202 ● MX Missile Basing

Figure 83.—Down Range and Cross Range Errors of a Ballistic

Reentry Vechile at a Target

SOURCE: Office of Technology Assessment.

ACCURACY OF SMALL SUBMARINE BASED MX

The object of having a missile with great accuracy is to have the ability to place warheads

sufficiently close to very hard military targets

so that there will be a high probability of destroying them. The ability to do this will in

general depend on the nature and the quality

of the guidance technology used by a missile

system and the range of that missile from its

targets.

The MX, as designed, is a purely inertial

guided missile. In the following presentation

the accuracy of a sea-based MX that uses purely inertial guidance will be discussed next, and

the accuracy of a sea-based MX that uses inertial guidance in conjunction with radio beacons will be discussed last.

Figure 84 is a graph of the CEP accuracy

multiplier for a sea-based MX with pure inertia I

guidance. A CEP accuracy multiplier of 1.0 on

the graph means that the expected CEP of the

missile at that range from target will be equal

to the engineering-design requirements for the

land-based MX. A CEP multiplier of 1.5 means

that the CE P at that range will be 1.5 times that

Figure 84.—Accuracy of Inertially Guided Sea-Based

Missile at Different Ranges From Targets

Land-based

MX accuracy

multiplier

012345 6

Missile range (thousands of nmi)

SOURCE: U.S. Navy.

of the design requirements of the land-based

MX, and so on. At present, it appears likely that

the land-based MX will have a smaller CEP

than that set for its design requirements, so a

CEP multiplier of 1.0 does not necessarily

mean accuracy equal to a land-based MX. The

graph assumes that the submarine’s position is

known within a few meters and that it would

use a velocity measuring sonar to measure its
Ch. 5—Small Submarine Basing of MX ● 203

velocity. None of the above assumptions present any operational problems for the submarine fleet (for reasons that will be discussed

later) and so this graph can be considered a

good operational representation of achievable

accuracies at different ranges from targets.

In order to illustrate the significance of

range from target effects for the small submarine-based MX missile, table 26 Iists a number of cities in the Soviet Union in regions that

also may have targets of military interest. The

number in the upper part of each of the boxes

in the table is the range from one of the three

submarine deployment areas to targets within

the regions surrounding these cities. In the

lower part of each box the expected hard target kill capability of a sea-based MX is compared to that of the hard target kill requirements for the land-based missile. It should be

kept in mind that the accuracy requirements

set for the land-based MX result in very large

single shot kill probabilities against targets of

great hardness. In fact, the single shot kill

probabilities used to compile table 26 are sufficiently large that differences described as

“slightly better, ” “comparable,” and “slightly

worse” r-nay not be of military significance (see

Classified Annex for numerical details).

If targets in the region around Novosibirsk

were to be attacked, warheads would have to

travel roughly 3,700 nmi to reach their targets.

The graph in figure 83 indicates that for that

range, warheads fired from the Gulf of Alaska

could have an expected accuracy at the target

SIightly better than the design requirements set

for the land-based MX. Missiles fired from the

Northeast Pacific deployment area would have

slightly worse accuracy than that of the landbased design requirements and missiles fired

from the Northwest Atlantic deployment area

would have still worse accuracy than those

from the Pacific area.

The significance of a slightly improved or

degraded hard target kill capability becomes

still less significant for hard targets which

merit attacks with more than one warhead. If,

for instance, a single warhead fired from one

submarine operational area had a probability

of 0.95 of destroying a particular hard target

and a second warhead fired from a different

submarine operational area had a 0.85 kill

probably against the same target, a 2-on-l attack would still have a greater than 0.99 probability of destroying the target being attacked.

This means that cross targeting could be performed from different operational areas with

considerable fIexibility.

This point is applicable even for targets in

areas that are extremely far from al I of the submarine operating areas. Even though these tarTable 26.—Comparison of Hard Target Kill Capabilities of Sea-Based MX”

With Design Requirements of the Land-Based MX

Relative hard target kill capability

Range to target from launch area Gulf of Alaska Northwest Atlantic Northeast Pacific

Moscow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Semipalatinsk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Vladivostok. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Novosibirsk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Minsk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Irkutsk. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Tashkent. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Tyuratam. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4,200

Comparable

4,000

Slightly better

3,000

Slightly better

3,700

Slightly better

4,100

Slightly better

3,400

Slightly better

4,600

Comparable

4,500

Comparable

3,900

Slightly better

5,200

Slightly worse

5,800

Worse

4,800

Slightly worse

3,600

Slightly better

5,200

Slightly worse

5,600

Worse

4,900

Worse

4,500

Comparable

4,700

Slightly worse

3,900

Slightly better

4,400

Comparable

4,600

Comparable

4,200

Slightly better

5,500

Worse

5,200

Worse

a Numerical values available in the Classfied Annex

SOURCE: Office of Technology Assessment
204 ● MX Missile Basing

gets are at very great distances from all the

submarine operating areas, and accuracy degrades with distance from target, such targets

will still be subject to successful attacks from

sea-based missiles in the late 1980’s and early

1 990’s.

The most extreme test of the system capability shown on table 26 are targets in the

region surrounding Tashkent, in the extreme

southern region of the Soviet Union (Tashkent

is about 200 miles from the Soviet Union’s

border with Afghanistan). Single warheads

fired from the Gulf of Alaska would have to

travel about 4,600 nmi to targets in that region

and would have single shot kill probabilities

comparable to the design requirements set for

the land-based MX. Missiles fired from the

other two operating areas would have to traverse much greater distances (about 5,600 and

5,500 nmi). The probability of destroying hard

targets in this region with a 2-on-1 attack using

missiles from any combination of submarine

operating areas would differ by only a few percent. Thus, even in the extreme case of very

distant hard targets, 2-on-1 targeting would

result in an almost indistinguishable difference

in capability to destroy very hard targets of importance.

If the targets were to be made still harder in

an attempt to increase their survivability

against sea-based warheads with the yield accuracy combinations used to construct table

26, it might be possible to gain several percent

more survivability against 2-on-1 attacks. The

small gains introduced by such a program,

would be enormously costly and could be

wiped out by additional possible improvements in accuracy.

Table 26 assumes that all missiles fired

against targets work, that is, it is compiled

under the assumption of 100-percent missile

reliability. If missile reliability is not better

than the single shot kill probabilities, missile

reliability wiII be more important a determinant of the hard target kill capability than accuracy. In the opinion of OTA, single shot kill

probabilities from sea-based missiles could be

so high by the 1990’s, that missile reliability,

not accuracy, will be the dominant factor

determining hard target kill capabilities.

The guidance technology assumed in table

26 assumes minimal changes to the MX missile

guidance system. The MX computation techniques used by the guidance system would

have to be optimized for sea basing rather

than land basing and high frequency gravitational data of the quality expected to be

available in the late 1980’s or early 1990’s

would have to be known within a 200-nmi

radius of the launch point. In addition, the

data summarized in table 26 assumes that the

submarine would know its position to several

meters and would use a velocity measuring

sonar to update its velocity. Analysis performed by OTA indicates that the use of

velocity measuring sonars does not introduce

either operational or vulnerability problems

for the MX-carrying submarines. However, if

the GPS were destroyed, the satellites would

not be avaiIable for position update immediately prior to missile launch. If the submarine did not take satellite position update

several hours prior to launch, knowledge of its

position would be sufficiently degraded that

the accuracy curve presented in figure 84

could not be achieved against distant targets.

This potential problem is, however, easily

solved by proper force management.

If antisatellite boosters or launches were

detected from American early warning sensors,

the submarines could be informed over VLF

channels that an attack on the satelIite navigation system could be in progress. In response

to this, the submarines would immediately proceed to update their navigational systems in

the hours before the intercepts. While performing the satellite fix the submarines could

simultaneously issue a “ready” signal to NCA

via the Deep Space Millimeter Wave Satellite

System. Since the submarines would be under

orders to avoid all shipping at all times, it

would be extremely unlikely that a submarine

could not take a fix within the time period

before loss of the satellites.

In the unlikely event that one or two submarines were unable to take a fix before hostil-
Ch. 5—Small Submarine Basing of MX ● 205

ities began, they couId immediately proceed to

the nearest acoustic transponder field. Thi s

would take the submarine between 2 to 3

hours. If a launch order were given during this

period of time, submarines with sufficiently

accurate guidance data couId be in a position

to launch without risk to the ship. Any submarine that had not reported a “ready” signal

tion. This could be done using VLF channels if

it only required reassignment of a prepackaged

option or it could require the high data rate

satellite I ink if ad hoc targets which are not

listed on the National Target List are to be attacked. This force management procedure

could therefore guarantee that the submarine

force could strike targets on short notice with

could immediately have its target package re- very higl

assigned to one of the other submarines on staACCURACY OF STAR-TRACKER-AIDED

accuracy.

NERTIALLY GUIDED MX

Heretofore only the accuracy that is likely

to be attainable using purely inertial measurements as a means of guiding the missile is considered. We now consider the additional accuracy that could be attainable if the inertial

guidance system is updated using some form

of external reference. First the use of star

trackers is discussed, and then the use of radio

beacons, as means of updating the missile’s inertial guidance system in order to obtain

higher accuracy at greater ranges.

It is possible to mount a device on the missile guidance platform that will allow it to take

a fix on a star after it leaves the atmosphere.

This technique is currently being used on the

new TRIDENT I missile and would be a more

significant modification to the MX missile

guidance system than that assumed in constructing table 26, Such a modification could

delay the deployment of the missile by a year

and cost several hundred milIion dolIars. However, as wiII be discussed in the section on

schedule, the submarines design and construction schedule shouId pace the missile development. Delays in the research and development

of the missile wouId therefore not be likely to

affect the date that the first missiles could be

put to sea.

The broad band in figure 85 shows a conservative estimate of the band of possible accuracies versus range for an MX-Iike missile

which has been fitted with a star tracker, As in

figure 84 the accuracy multiplier is defined

with respect to the engineering design requirements of the land-based MX missile. The upper

part of the band is the accuracy versus range

curve that is very likely to be achieved in the

late 1980’s or early 1990’s. The three vertical

arrows define the distances to Tashkent from

the Gulf of Alaska, Northeast Pacific, and

Northwest Atlantic deployment areas. As can

be seen from the graph, it is very likely that all

targets in the Soviet Union could be attacked

in the late 1980’s or early 1990’s from all

submarine operating areas with accuracies

marginally better or worse than that of the

engineering design requirements of the landbased MX. The lower part of the band represents a conservative estimate of what is possible in the late 1980’s or early 1990’s if the advanced MX inertial measurement unit is used

in conjunction with a star tracker. If this level

of performance is reached, all targets could be

covered from all deployment areas with CEPs

at least as good as the engineering design requirements of the land-based MX,

For purposes of reference to the earlier discussion, the dashed line plotted in figure 85

shows the accuracy multiplier versus range for

an MX missile guided without the aid of a star

tracker. The hard target kill probabilities used

to construct table 26 and discussed earlier in

this section are derived from this curve. Since

the addition of a star tracker to the inertial

guidance package helps reduce certain rangedependent guidance errors during the early

stages of flight, the star tracker aided inertially

guided missile displays a weaker degradation
206 ● MX Missile Basing

Figure

Land-base

MX CEP

multiplier

85.—Accuracy of Star-Tracker=Enhanced Sea= Based Missile as a

Function of Range From Target

I

d

2000 4000 6000

Range (nmi)

SOURCE: U.S. Navy

of accuracy with range relative to that of the

purely inertial guided MX.

It should be noted that the star tracker accuracy versus range curve shown in figure 85 is

derived on the basis of assumptions about the

availability and capability of certain technologies relevant to guidance, quality of navigational data at the time of launch, and knowledge of geophysical data around the launch

point and along the missiles trajectory. The

assumptions are as follows:

position and velocity data at time of launch.

Accurate data at time of launch could be

obtained with the aid of: acoustic transponders, velocity measuring sonars, and the

Global Positioning System.

2. Introduction of gravity gradiometers on

submarines and/or quality high frequency

gravity data within 200 nmi of the launch

point. It is expected that these technologies

and data will be available in the period of

the late 1980’s to early 1990’s.

1. An Improved Submarine Inertia! Navigation System (SINS) and/or accurate initial

DEGRADATION IN ACCURACY AFTER A

SUBMARINE NAVIGATION FIX

Because a star tracker enhanced, inertial It is expected that submarine inertial navigaguided missile is able to obtain navigational in- tion systems will be considerably improved

formation by sighting on stars during its flight, even relative to their currently impressive

its accuracy at range is not as sensitive to navi- capabilities. Improvements in inertial guidgational uncertainties introduced by the con- ance technologies, gravitationaly mapping and

tinuous motion of its launch platform, as is the the use of star trackers on missiles is expected

case with a purely inertial guided missile. to dramatically lengthen the time needed be-
Ch. 5—Small Submarine Basing of MX . 207

tween navigational updates of the submarine or even weeks in order to maintain sufficient

inertial guidance system. I n the 1990’s, naviga- capability to attack very hard targets from sea.

tional updates would not be

INERTIAL

required for days

GUIDANCE AIDED BY RADIO UPDATE

The two sets of accuracy data so far discussed are based on improvements in inertial

guidance technologies that are used in missiles

and in submarines, and on improved geodetic

and gravitational data.

Another set of guidance technologies that

could be used to obtain high accuracy with

sea-based missiles without precise navigational data at launch and extensive gravitational mapping is a system based on inertial

guidance aided by updates from radio navigation aids.

Radio updates could be taken with the aid

of the GPS. They could also be taken with the

aid of a system of ground radio beacons CBS

(also refered to as an Inverted GPS), that could

be emplaced on the continental United States.

In the event that the GPS is attacked using antisatellite weapons, the GBS could provide

backup radio navigation aids to the missiles in

flight. Unlike the GPS, the CBS would only

operate during a crisis, and could be made

costly to attack by constructing many radio

beacons and decoys.

The sea-launched missile could radio update

its inertial guidance system in three different

ways, The missile could take a navigational fix

using GPS to update its inertial guidance system before it deploys its reentry vehicles from

the missile’s post boost vehicle (i. e., the missile’s bus). In the event of outage of the CPS,

the navigational fix could instead be taken

using the ground beacons. I f the GPS were

destroyed and the ground beacons were used

as a backup system, it would be necessary to

take a radio fix through the ionosphere. This

radio fix might be disrupted if there were

nuclear detonations occurring in the ionosphere. In order to avoid disruptions of this

type, a radio fix could be taken before the

missile reaches the bottom of the ionosphere,

perhaps at an altitude of about 50 miles.

The first two of these methods should provide MX accuracy at all ranges from Soviet

targets. If the GPS were used, missiles could be

launched from anywhere in the submarine deployment area. If the ground beacons were

used, system accuracy would be degraded if

the submarines were not with in 700 to 900 nmi

of the continental United States. This degradation would occur due to errors introduced into

the navigational update by poor line of sight

geometry on the ground beacons. Figure 86

shows the areas of ocean from which a CE P

multiplier of one could be achieved if ground

beacons were emplaced on the continental

United States, Alaska, Hawaii, and on the

Aleutian Islands. Figure 87 shows the additional Pacific area from which the same CEP

multiplier could be achieved if the ground

beacons were also emplaced on the islands of

Wake, Guam, Kwajalein, Palau, and Tafuna,

Samoa.

If the ground beacons were used to update

the missile guidance system before the missile

reached the ionosphere (this update could be

necessary if the GPS system had been destroyed and the ionosphere was disturbed by

the detonation of nuclear weapons) the submarines would have to be within 400 to 500

miles of the continental coast if a radio update

is to be possible before the lower ionosphere is

reached. Using this method of update, a CE P

multiplier of 1.0 to 1.5 that of land-based MX

might be achievable. Unfortunately, calculations on this type of update have not been

performed in detail and a more accurate assessment of the capability of this type of update is not available.

In summary, a sea-based MX could be

guided using purely inertial measurement

technologies or with inertial measurement

technologies updated by sighting on stars or

radio beacons. The star trackers offer a great
208 ● MX Missile Basing

Figure 86.—Ocean Areas That Provide Adequate Line-of-Sight View of Ground Beacons on

Continental U. S., Aleutian Islands, Alaska and Hawaii

90.001 I

– 70.00

– 90.00* 1

0.00 30.00 60.00 90.00 120.00 150.00 180.00 210.00 240.00 270.00 300.00 330.00 360.00

Longitude

SOURCE: Office of Technology Assessment.

advantage in that they are a self contained ele- By deploying a large enough system of ground

ment of the missile and have been demon- beacons and decoys as a backup to the satelstrated to be highly reliable. Radio beacons on Iite beacons, the risk from Soviet countermeassatellites, and on land, also can be used for up- ures could be kept small.

dating the missile’s inertial guidance system.

TIME ON TARGET CONTROL

If the submarine system is to attack hard Since the small submarine would carry

targets with more than one warhead, there is a missiles in external capsules that would be

need to control the time at which warheads ar- Iaunched at different depths under different

rive at targets with a high degree of accuracy. operational conditions, the exact time at

This control is needed so that the detonation which a missile flew out of the capsule could

of the first warhead will not interfere with the possibly effect the arrival of warheads at

arrival the second warhead. targets. In practice, this problem could be
Ch. 5—Small Submarine Basing of MX ● 209

Figure 87.—Ocean Areas That Provide Adequate Line”of-Sight View of Ground Beacons on

Continental U. S., Aleutian Islands, Alaska, Hawaii, and Selected South Sea Islands

90.00 1

—

m

– 90.00 ~ 1 I I 1

. . I I

0.00 30.00 60.00 90.00 120.00 150.00 180.00 210.00 240.00 270.00 300.00 330.00 360.00

Longitud e

SOURCE Off Ice of Technology Assessment

solved by assigning each missile a time at lofted or depressed relative to the planned trawhich warheads are to arrive at targets. Uncer- jectory). Care would have to be exercised in

tainties in launch time could then be compen- the design of the fire control and guidance

sated for by changing the missile’s trajectory package to assure that this could be done.

(i.e., the missile trajectory could be slightly

RESPONSIVENESS OF THE SUBMARINE FORCE

The responsiveness of the submarine force is without warning. The time necessary for these

determined by the speed with which an Emer- calculations wou Id be of order a few minutes

gency Action Message (E AM) could be trans- and would not be a factor I ikely to delay a

mitted to the force and the time required for launch.

the submarines to launch their missiles. The

calculation of trajectories to target sets must Therefore, the two time periods that would

be performed for both land- and sea-based mis- dominate the ability of the submarine force to

siles if targets are reassigned to a missile respond rapidly to an EAM would be the time
210 ● MX Missile Basing

period needed to receive the EAM and the

time period needed to prepare the submarine

for the launch of missiles. The EAM could be

received in a pre- attack or transattack period

within a few minutes. If the submarines were

ordered to execute a preplanned strike, all

data necessary for the strike would be available at the reception of the EAM and the time

required to initiate the strike would be determined by the time that could be needed to

bring the submarines to launch depth. This

time could be several minutes.

If the ordered attack were not a preplanned

option, there could be two different categories

of target sets chosen, those that are stored in

the guidance computer and those that are designated ad-hoc in terms of their latitude, longitude and height of burst. If the target list required a high data rate link, the VLF link would

ENDURANCE

I n the event of a protracted nuclear exchange, surviving IC BMs might be required for

strikes weeks or months after an initial exchange. These forces wouId be executed from

surviving command and control centers using

whatever communications c ha n n e Is were

ava i I able.

The survival of command and control channels and the availability of communications

channels during a protracted nuclear exchange

is a common problem for both land- and seabased forces. However, the endurance of the

ICBMS themselves would differ with the basing

mode.

The small submarine could be constructed

to have an at-sea endurance of more than 90

days without support from tenders. It is

assumed, based on U.S. Navy operating exCOST AND

The small submarine basing concept is envisioned as a fleet of 51 diesel-electric submarines, each of about 3,300 tons submerged

not be appropriate. In this circumstance, a

coded message would be sent over VLF for a

particular submarine, or group of submarines,

to come to depth and copy a new target Iist

using the EHF satelIite I ink Alternatively, if

the submarine force were diesel-electric powered (rather than nuclear powered), the fraction of the force that was snorkeling could

receive the ad-hoc targets as well. After recept ion of data, which would take only a minute

or two over the EHF Iink, the submarines couId

immediately prepare for Iaunch by proceeding

to launch depth, provided the strategic weapon system is configured to directly accept and

validate the data from the satellite Iink.

Launch of the missiles could take place shortIy

thereafter. The rapidity of response of the

system couId therefore be of order 10 to 15

m i nutes

OF FORCE

perience, that a normal submarine patrol

would last for 60 days. This assumption means

that for 30 days after an initial attack, no submarines would have to return to port. About 5

percent of the missiles at sea would be lost due

to missile failures during this time. Sixty days

after an initial exchange, about half the force

would still be capable of remaining at sea. If

the missiles were not operated in a dormant

mode (so that they could be fired on a minute’s

notice rather than on an hour’s notice) about

10 percent of the missiles could be expected to

have failed at the end of 60 days. Thus, 9

weeks after an initial attack, the submarine

force could deliver about 400 warheads

against an enemy. By 12 weeks after an exchange, the number of operational missiles at

sea wouId have diminished to zero.

SCHEDULE

displacement. Each submarine would be capable of carrying four externally encapsulated

MX missiles. The submarines would be manned
Ch. 5—Small Submarine Basing of MX ● 211

with a crew of about 45 members and would

operate within 1,000 to 1,500 nmi of thre e

bases. One of the bases would be located on

the east coast of the continental United States,

another would be on the west coast, and the

third would be located on the coast of Alaska.

The acquisition cost of the system of submarines, bases, navigational aids, and related

operational and support equipment is estimated to be about $32 billion (fiscal year 1980

dollars). An operating and support cost of $7

billion is estimated for a 10-year system lifecycle, The total cost of the system is estimated

to be about $39 billion. The details of this cost

estimate at the major subsystem level is presented in table 27.

The deployment schedule for a system of

small submarines is shown in figure 88. This

schedule would vary with the degree of commitment the nation makes to a new strategic

weapon system. If the commitment is such

that slippage is not allowed due to unforeseen

technical setbacks, funding cuts, environmental law suits, or other actions that could require congressional action, an initial operational capability (IOC) in the middle of 1988

could occur. It could even be possible to have

a lead ship by the end of 1987, but this would

require a very high degree of national commitment. A more realistic estimate based on a

review of military programs over the past

decade would place IOC in 1990. If IOC ocTable 27.—Small Submarine 10-Year Lifecycle Cost

(billions of fiscal year 1980 constant dollars)

Cost element Number cost

RDT&E:

Submarine. . . . . . . . . . . . . . . . . . — $0.422

Missile . . . . . . . . . . . . . . . . . . . . — 6.056

Sws . . . . . . . . . . . . . . . . . . . . . . . – 0.400

Capsule . . . . . . . . . . . . . . . . . . . . — 0.257

Navigational aids . . . . . . . . . . . . — — . —0.090

Total RDT&E . . . . . . . . . . . . . . . . . . . . . . . . . $7.225

Procurement:

Submarine. . . . . . . . . . . . . . . . . . 51 $ 6.682

Basing . . . . . . . . . . . . . . . . . . . . . 3 7.240

Missile . . . . . . . . . . . . . . . . . . . . . 470 5.419

Sws . . . . . . . . . . . . . . . . . . . . . . . 51 2.397

Capsule . . . . . . . . . . . . . . . . . . . . . . 521 1.725

Navigational aids . . . . . . . . . . . . . . 1,500/3,000 1.399

Total procurement . . . . . . . . . . . . . . . . . . . . - $24;862

Total acquisition. . . . . . . . . . . . . . . . . . . . . . . . . . $32.087

Operating and support:

IOC to FOC . . . . . . . . . . . . . . . . . . . . . . . . . . . . $ 2.392

FOC to year 2000 . . . . . . . . . . . . . . . . . . . . . . . 4.868

Total operating and support . . . . . . . . . . . . . . . . $=.16 0

Total to year 2000 LCC. . . . . . . . . . . . . . . . . . . . . $39.247 —

Average acquisition $/submarine, . . . . . . . . . . . $0.62 9

Average LCC/submarine to year 2000. . . . . . . . . 0.770

Average acquisition $/deployed missile . . . . . . 0.157

SOURCE Off Ice of Technology Assessment

curred in 1988, full operational capability

(FOC) could be achieved in late 1992. If the

more realistic estimate of a 1990 IOC occurs,

FOC would occur in early 1994.

It should be noted that the costing of the

submarine system assumes Navy procurement

Figure 88.—Small Submarine Program Schedule

.; * . -.% .“ ‘ . .

, ,

Missile avaikblllty ‘ : ‘ . . ‘e ‘ .“‘. ~ *: .$ *., - , - . .

, >

. j

Base m$w*Jq ,

. * -, i ’ .’ -..

Submarine $ ~,

Head ship proc. A

Initial operations (IOC) A

Full operations (FOC) (Ioc) A

(FOC)

SOURCE Office of Technology Assessment
212 MX Missile Basing

practices for the MX missiles. In order to have

100 missiles alert at sea at all times 470 missiles are obtained. The land-based Air Force

baseline procures 330 missiles. The additional

missiles are obtained since it is assumed that

Navy experience developing sea-based missiles

would apply to the MX if it were deployed at

sea. These missiles would be used in an extensive program of testing and evaluation similar

to that of the Trident/Poseidon programs.

It should also be noted that three bases are

included in the costing. Since the submarines

postulated for this system would have a considerable at-sea endurance, it would be possible to deploy them from two bases instead of

three. However, each of the bases would have

to be larger in order to handle additional submarines. These bases would normally service

nine to ten submarines instead of six to seven.

SYSTEM SIZE

The number of submarines acquired was

chosen so that 100 MX missiles would be available at sea for retaliation against the Soviet

Union regardless of preemptive actions on

their part. The choice of 100 surviving missiles

was arrived at using the following reasoning:

The number of small submarines required

for a sea-based MX system is determined by

the perceived need to be able to attack a

predetermined number of targets after any

enemy action. The number of targets that the

United States could attack after a Soviet first

strike would depend on the number of missiles

that survive such an attack.

It is assumed that all at sea-submarines

would effectively survive an ICBM attack. This

assumption is based on a review of the capabi1-

ities of antisubmarine technologies and forces.

A barrage attack is not considered a significant

threat for the following reasons:

The Air Force MX/MPS baseline has 200 missiles hidden among 4,600 shelters. For purposes

of analysis, it is assumed that half of the Iandbased MX force will survive a determined

Soviet attack. This assumption would mean

that no more than 2,300 hard target capable

warheads landed in the MX/MPS fields close

enough to shelters to destroy them. A barrage

attack with this number of warheads might

result in the destruction of one to two submarines at sea. This does not represent a

significant attrition of the submarine force.

The number of small submarines required to

maintain 100 missiIes at sea in an “up” status is

determined by the number of missiles per submarine Mps, the fraction of missiles in an “up”

status Fmu the fraction of the time a submarine is at sea during a patrol cycle Fas the

fraction of submarines that are in overhaul or

on restricted availability For and the fraction

of submarines that are expected to survive an

at-sea attack Fss. The total number of small

submarines N required to maintain 100 missiIes

is then given by:

N 100

where

N = the total number of submarines required to deliver

1,000 RVS

Mps = the average number of missiles per submarine

F = the fraction of submarines in overhaul or restricted

avaiIabiIity

t ,,. = the traction of time submarines are at sea during a

patrol cycle

F mu = the fraction of missiles In an “up” status at sea

F \\ = the fraction of the at sea submarines surviving

after an attack

Since the missiles would be in capsules external to the hull of the submarine, they could

not be serviced while the submarine is at sea.

Hence, the failure of a missile at sea would put

it in a down status for the remainder of the atsea patrol.

The fraction of missiles available at sea during a patrol period of T days wilI be:

1 s

T –

(It

I

where 7 Is the mean t I me between failure o f

the missile and the is the Iength of time of the submarines is on patrol
Ch. 5—Small Submarine Basing 01 MX ● 213

Since each submarine will spend T days at

sea and TIP days in port, the at sea availability

of the submarine during a normal patrol cycle

Is:

F l\

T + ,,,

If a submarine spends 12 months in overhaul

or in restricted availability during each 5-year

operating period, then O = 0.8.

Table 28 presents the number of submarines

that would be required to maintain 100 missiles on station for different patrol periods at

sea and for different times in port for refit. It is

Table 28.—Number of Submarines Required To Keep

100 MX Missiles Continuously on Station v.

Submarine In-Port Time

Patrol period (days). . . . . . . . . . 40 50 60

Number of submarines at sea . 26 26 27

Total submarine force size:a

12 days in port . . . . . . . . . . . . 42 (40) 41 (38) 40 (38)

15 days in port . . . . . . . . . . . . 45 (42) 43 (40) 41 (39)

18 days in portb . . . . . . . . . . . 47 (44) 45 (42) 43 (41)

21 days in port . . . . . . . . . . . . 50 (47) 47 (44) 45 (45)

24 days in portc . . . . . . . . . . . 52 (49) 49 (46) 46 (44)

a Total force numbers assume that 20 percent of att submarines will be in

extended refit or overhaul and are therefore unavailable Numbers in paren

theses assumes 15 percent of the force in overhaul or extended refit.

b Naval Sea Systems Command estimates minimum time in Port required for

refit IS 18 days.

c OTA assumes 25 days in port for refit and handling of missiles

SOURCE Off Ice of Technology Assessment

assumed that 100 percent of the submarines

survive preemptive enemy action and that 20

percent of the submarine force is either undergoing overhaul or is in restricted availability.

The numbers in parentheses assume 15 percent

of the submarines are in overhaul or restricted

availability instead of 20 percent. Thus, if it

proved feasible to perform refit operations in

18 days (instead of OTA’S assumed 25 days)

and to have 15 percent of the submarines in

overhaul and extended refit, it would be possible to maintain 100 missiles on station with a

fleet of 41 submarines, rather than the 51 submarines assumed by OTA. The at-sea factor is

the fraction of the submarine force that is

always at sea. It is defined as:

at-sea factor = F<,, (1 – F,,)

An at-sea factor of 55 percent is assumed in

order to estimate the total number of required

submarines. This factor is also used to estimate

the number and size of base facilities required

for servicing submarines between patrols.

In order to provide 100 at-sea missiles (or alternatively 1,000 surviving warheads) at all

times, the at-sea reliability of the missiles must

be factored into the sizing of the fleet. It is projected, from engineering requirements, that 95

percent of the missiles at sea would be in an up

status for a fleet of submarines with an at-sea

patrol of length 60 days.

FINAL SIZING CONSIDERATION

In the final sizing of the system, it was

assumed, in order to establish a conservative

cost estimate, that 10 percent of the missiles

might not function on a launch command and

it would be necessary to maintain more than

100 “up” missiles at-sea. This assumption

added 4 submarines to a procurement which

would otherwise have been 47. The costs of

procuring, operating and supporting additional

crews, missiles, capsuIes, and strategic

weapons systems is of the order of $1 billion to

$2 billion.

LOCATION AND DESCRIPTION OF BASES

Base selection was limited to the continen- The perceived need for responsiveness, flextal United States since the submarine force is ibility, and weapon system effectiveness dicdesigned to operate in deep ocean areas adja- tated that the submarines be able to move

cent to the continental United States. rapidly to acoustic transponder fields to main-
214 ● MX Missile Basing

tain accuracy in the event of outage of the

GPS. A very large operating area would spread

the acoustic transponder fields over a large

area of ocean, resulting in possible execution

delays due to long transits to transponder

fields. In addition, time on station could be

maximized without the need of a submarine

with a high transit speed. It should be noted,

however, that none of the above considerations truly dictate a need for such a limited

deployment area.

The Gulf of Mexico was rejected as a deployment area for the folIowing reasons:

diesel-electric submarine technology has

achieved a level of quieting that would not

restrict the submarines to acoustically shallow

water even if a large-scale advanced passive

sonar threat emerged. The acoustically shallow water of the Gulf of Mexico therefore offered no clear survivability benefits to offset

the range/payload/accuracy missile performance penalties associated with that deployment area.

It is assumed that a detailed review of possible base locations would be made if there was

a decision to deploy a fleet of small submarines. In order to provide a basis for estimating costs, three base locations on the east

and west coasts of the continental United

States and Alaska were assumed. These are:

. Anchorage, Alaska

. Puget Sound Area, Wash.,

● Narragansett Bay, R. 1.

Each of the sites has problems of its own.

The arctic winters, long winter nights, and extreme weather at the Anchorage site would

pose problems clearing ice, loading and off

loading missiles, maintaining and refitting submarines, and supporting crews at the base. The

Puget Sound area already has a Trident base

(Bangor, Wash.). Construction at the Narragansett Bay site could be delayed due to competition for the land from the Rhode Island Government.

Other possible secondary sites could be:

● San Diego, Cal if.,

● Charleston, S. C.,

● Kingsbay, Ga.

These possible sites also offer their own

problems. San Diego would be unlikely to provide enough waterfront area without displacing existing Navy operations. Charleston and

Kingsbay could be too far south for the most

efficient deployment of submarines in the

northern coastal areas of the Atlantic.

Since SSBN fleet support is shifting to Kingsbay, waterfront area may become available in

Charleston for submarine support in Charleston while MX support might be provided at the

new SW FLANT facility at Kingsbay. Tradeoff

studies would have to be performed in order to

evauate the sensibiIity of these options.

In order to develop a conservative estimate

of the size, number, and cost of facilities at the

small submarine base, an analysis of the Trident base facility at Bangor was made. Approximately 85 to 90 percent of the Iand required

for the base is dictated by explosive weapons

safety requirements and facilities for handling

strategic weapons. It was assumed that the

amount of land required scaled with the number of strategic weapons on the base. This

number includes the missiles on the submarines, missiles stored for operational tests, and

missiles stored for demonstration and shakedown operations. These assumptions lead to

the conclusion that 4,450 acres would be required for the base. other assumptions could

lead to a smaller less costly base but they

would only be justified if a more detailed feasibility analysis could be performed.

The size of the base arrived at for the

costing analysis is approximately 500 acres

larger than a base sized in an earlier study of

small submarine basing performed by the System Planning Corp. for the Navy. Table 29

compares the estimated small submarine base

with the Trident base at Bangor.

Table 29.–Estimated Characteristics of the Small

Submarine Refit Site and the Trident Refit Site

Small

submarines Trident

Total area (acres) . . . . . . . . . . . . . . . . . 4,450 8,397

Waterfront length (feet). . . . . . . . . . . . 11,630 4,248

Number of submarines in port . . . . . . 5/6 3

Number of explosive handling

wharfs . . . . . . . . . . . . . . . . . . . . . . . . 1 2

Number of refit berths. . . . . . . . . . . . . 4/5 3

Drydockets/graving docks . . . . . . . . . 1 1

SOURCE Off Ice of Technology Assessment.
Chapter 6

AIR MOBILE MX
Chapter 6.–AIR MOBILE MX

Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Page

217

Three Air Mobile MX Concepts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. ...219

The importance of Missile Size . . . . . . . . . . . . . . . . . . . . . . . . .219

Continuously Airborne. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...219

Dash-on-Warn

Dash-on-Warn

Survivability . .

ng With “Endurance”. . . . . . . . . . . . . . . . . . . . . . . . . . 221

ng Without’’Endurance” . . . . . . . . . . . . . . . . . . ........221

. . 222

Aircraft Vulnerabilityto Nuclear Effects. . . . . . . . . . . . . . . . . . . . . ..222

ICBMBarrage of in-Flight Aircraft. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .223

SLBM Attack On Dash-on-Warn

Endurance. . . . . . . . . . . . . . . . . .

ngAirMobile . . . . . . . . . . . . . . . . . . . . . . 225

. . . . . . . . . . . . . . . . . . . . . . . . . . . 228

Costs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .......230

Continuously Airborne. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .230

Dash-on-Warning With’’Endurance”. . . . . . . ...........23 0

Dash-on-Warning Without “Endurance”. . . . . . . . . . . . .231

Support Systems . . . . . . . . . . . . . . . . . . . . . .231

WarningSensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .231

Command, Control and Communications ( C

3

. . . . . . . . . . . . .. ....231

MissileGuidance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...232

FIGURE S

89. Survivability v. Escape Time . . . . . . . . . . . . . . . . . . . . . . . . . .

Page

226

90. Aircraft Survivability During Base Escape. . . . . . . . . . .227

91. Aircraft Survivability During Base Escape. . . . . . . . . . .227

92. Aircraft Survivability During Base Escape. . . . . . . . . . .227

93. Aircraft Survivability During Base Escape. . . . . . . . . . .227

94. Aircraft Survivability During Base Escape . . . . . . . . . . . . . . . . . ........228
Chapter 6

AIR MOBILE MX

Air mobile basing offers the prospect of high

survivability, since missile-carrying aircraft in

flight would move much too fast to be targeted by Soviet missile forces. However, unless

the aircraft were airborne continuously, their

survival would depend on taking off upon

early warning of attack. Moreover, they would

have to find surviving airfields to land and refuel if they were to have endurance, i.e., to be

a useful force beyond the first few hours of a

war.

This chapter discusses three concepts, distinguished by their approaches to the problems of dependence on warning for survivability and postattack endurance beyond the unrefueled flight time of the aircraft. The basic

concept (called below “Dash-on-Warning

without ‘Endurance’”) wouId consist of missile -

carrying aircraft on strip alert at a number of

inland airfields. The force would take off on

warning of Soviet attack and would land and

refuel after a few hours at existing civilian and

military airfields unless the Soviets had destroyed these airfields. The second concept

(“continuously Airborne”) would avoid the

problem of dependence on warning by maintaining the missiles in the air continuously.

Such a system would be exceedingly expensive. The third concept (“Dash-on-Warning

with ‘Endurance’”) would attempt to address

the problem of postattack endurance by

building a large number of recovery airfields

throughout the United States, forcing the

Soviets to attack all of them in order to deny

endurance to the force. This concept would

also be expensive. The base case, involving

dependence on warning and no provision for

endurance beyond existing airfields, could

have a cost comparab

MPS system.

OVERVIEW

The lowest-cost, base case air mobile system

would consist of 75 or so wide-bodied aircraft,

each carrying two MX missiles, maintained on

strip alert at airfields located in the Central

United States. Such a “dash-on-warning” air

mobile force could be highly survivable. The

principal threat to the force would be submarine-launched ballistic missiles (SLBMS)

launched from positions near U.S. coasts. Such

an attack could arrive in the vicinity of the

alert airfields within 15 minutes of launch and

seek to destroy the aircraft before they could

take off and escape. However, if a high alert

posture were accepted for the force, meaning

that the aircraft took off immediately on timey warning of SLBM attack, almost the whole

force would survive even if a large number of

SLBMS was launched from positions near U.S.

coasts. The Soviet SLBM force is presently incapable of such an attack, Air mobile basing

could therefore stress Soviet strategic forces

e to that of the baseline

where they would be least able to respond in

the short term.

Nevertheless, the difference between survival and destruction of the force would be a

very few minutes, depending on timely tactical

warning. I n this respect an air mobiIe intercontinental ballistic missile (ICBM) force

would replicate a significant failure mode of

another leg of the strategic Triad — the bomber

force.

ICBMS, arriving later than the SLBMS, could

not threaten the survivability of the entire

force, since by that time the aircraft would

have been in flight long enough to be dispersed

over a wide area. Effective barrage attack of

this entire area would require the Soviets to

build many more large ICBM missiles than they

now possess and use them to barrage approximately 1 million square miles (mi 2

). The outcome of such an attack wouId be insensitive

83-477 0 - 81 - 15 217
218 ● MX Missile Basing

both to the fractionation (the apportioning of

the missile payload among a small number of

large-yield reentry vehicles (RVS) or a large

number of smaller yield RVS) and to the accuracy of Soviet ICBM forces.

The principal disadvantage of a dash-onwarning force— the need for reliable, timely

warning—could in principle be removed by

having the aircraft maintain continuous airborne patrol. However, even with a new aircraft with lower fuel consumption, the cost of

operating such a force would be prohibitive. A

continuously airborne force of 75 aircraft (150

MX missiles) could have a Iifecycle cost of $80

billion to$100 billion (fiscal year 1980 dollars).

A second crucial problem for an air mobile

force concerns the question of postattack endurance. After a few hours of flight, the aircraft would have to land and refuel. Since their

home airfields would be destroyed, they would

have to find other places to land and await further instructions. This problem could be

avoided completely if the United States were

willing to adopt a policy of “use it or lose it”

for the few hours of unrefueled flight. There

are also several hundred civilian and military

airfields in the United States capable of servicing large aircraft. Many of these airfields are

located close to urban areas. If the Soviets

wished to deny postattack endurance to an air

mobile fleet—tantamount to forcing the

United States to “use it or lose it”- they would

have to attack these airfields. A serious effort

to build more austere recovery airstrips

throughout the country than the Soviets possessed ICBM RVS to destroy them would be

enormously expensive, would have substantial

environmental impact, and would be completely impractical if the Soviet threat grew

large. For instance, 4,600 airfields spaced 25

miles apart would fill the entire 3 million mi 2

of the continental United States. Closer spacing might be possible, but beyond a certain

point the spacing would become so close that

local fallout from attack on one airfield would

make extended operations at neighboring airfields impossible. Thus, cost aside, it might be

impossible to guarantee survival of usable

recovery airfields against a greatly expanded

Soviet ICBM arsenal.

There could conceivably be some value in

having more airfields suitable for air mobile

operations than the Soviets had SLBM RVs.

These airfields could be useful if the United

States doubted the reliability of its SLBM

warning sensors and wished to relax the force’s

alert posture (since, in a crisis, false-alarm

takeoff might be mistaken by the Soviets for

preparation to launch the MX missiles), or if

the fleet were somehow “spoofed” into taking

off (thus making a portion vulnerable as the

aircraft were forced to land).

There are about 2,300 airfields in the United

States that, with upgrades, could accommodate an air mobile force in the postattack

period. However, to make use of most of them,

it would be necessary to deploy smaller shorttakeoff aircraft. Since the smaller aircraft

could only carry one MX missile, twice as

many of them would be required to make a

force equivalent to a wide-bodied jet force.

Between the cost of the aircraft and the

recovery airfields, a force with this dispersal

option could cost $10 billion to $40 billion

(fiscal year 1980 dollars) more than a widebodied jet force with no recovery airfields

beyond existing large civilian and military airfields.

Thus, the lowest cost air mobile system

would consist of wide-bodied jets, each carrying two MX missiles, with no extra recovery airfields beyond those large civilian and military

airfields that exist at present. The cost of such

a system would depend on whether it was desired to have 200 MX missiles on alert (100 aircraft), 100 surviving MX missiles (50 aircraft,

assuming 100-percent survival with prompt

warning and takeoff), or some other number.

Although OTA has not performed detailed cost

and schedule analysis for such an air mobile

option, it appears that the cost of a force with

75 aircraft (150 MX missiles) on alert could be

comparable to the cost of the baseline multiple protective shelter system and could be deployed in a comparable time.

An air mobile force would also require several supporting systems. First and foremost

would be reliable sensor systems for timely

warning of Soviet attack. Providing such sys-
Ch. 6—Air Mobile MX ● 219

terns would be technically feasible but would Last, providing f o r

require time, money, and continued effort. The parable to (or even

complex force management needs of the air would require the G

mobile force after attack would require a com- (GPS) system or a

parably complex communications system. (CBS).

missile accuracy combetter than) land basing

obal Positioning Satellite

Ground Beacon System

THREE AIR MOBILE MX CONCEPTS

The Importance of Missile Size

The size and weight of the missile determine

the type and number of aircraft needed for an

air mobile force. A large missile like MX would

require a large aircraft, and only one or two

missiles could be carried by each aircraft.

Large aircraft require long runways. Since the

number of U.S. airfields with long runways is in

the hundreds, whereas the Soviet ICBM RV arsenal is in the thousands, an air mobile fleet

with large aircraft could not count on finding

landing sites when fuel ran low several hours

after a Soviet attack.

A smaller missile could be carried by smaller

aircraft, and these smaller planes would have

many more possible sites — including unprepared surfaces, highways, and even waterways

if fitted with pontoons—for postattack reconstitution. On the other hand, a smaller missile

would carry fewer RVS, meaning that a smallmissile air mobile force would require many

more aircraft in order that the total deployment have as many RVS as a large-missile

force. This large number of aircraft would in

turn be costly.

There is thus a tradeoff in cost between

small and large missiles for air mobile deployment. This study considers only the MX missile,

capable of carrying 10 RVS to intercontinental

range.

The ground-launched MX missile weighs

190,000 lb. For the purposes of air launch, the

first stage of the MX could be modified to reduce the missile weight to about 150,000 lb

with no penalty in range or payload. This

weight reduction would allow large aircraft to

carry two MX missiles.

There are two reasons why an air-launched

missile can be lighter than a ground-launched

missile of equal range and payload. First, an

air-launched missile begins its flight 10,000 to

30,000 ft higher than ground-launched missiles

and therefore does not need propellant to

carry it to that altitude. This effect is actually

small. A much larger contribution to weight

reduction comes from the fact that a missile

that begins its flight at high altitude can accelerate faster. Ground-launched missiles must

accelerate slowly because if they attained high

speed within the atmosphere they could be

damaged by dynamic pressures and aerodynamic heating. Slow flight means that the

missile uses much of its propel I ant just holding

itself up against the pull of gravity in the early

part of its flight. An air-launched missile can

accelerate quickly because by the time it attains high speed the air is too thin to damage

it.

The higher thrust-to-weight ratio of the airIaunched missile means that the MX first stage

couId be truncated to a point where the missile

weighed only 150,000 lb. (A brand new missile

could probably be designed to attain MX capabilities at even lower weight. Cylindrical geometry would also not be necessary for a new

missile. )

For the purposes of this chapter, then, the

MX missile with a smaller first stage and

150,000 lb weight will be assumed.

Continuously Airborne

This concept might consist of a fleet of large

turboprop aircraft, each carrying two MX missiles, maintaining continuous air alert. The size

of the deployment — a factor in cost—would
220 ● MX Missile Basing

depend on whether it was desired to have 200

alert missiles (100 airborne aircraft), 100 surviving missiles (50 aircraft, assuming perfect survivability), or some other number. The aircraft

would maintain relays of 8-hour patrols, with 2-

hour turnaround for each aircraft at the end of

a patrol. Ocean patrol areas would remove the

aircraft from congested overland air corridors

and minimize the consequences of accidents

involving the explosive propellants and nuclear warheads carried aboard.

Turboprop propulsion would reduce fuel

consumption and prolong patrol cycles relative to conventional jet aircraft of the same

size. No large turboprop aircraft are presently

manufactured in the United States, but it

would be technicalIy feasible to develop a new

aircraft, with consequent cost and schedule

penalties. A four-engine turboprop aircraft of

about 900,000-lb gross weight carrying two

150,000-lb MX missiles might be capable of 14

hours of unrefueled endurance and 2,500-mile

range.

Continuously airborne operations would be,

exceedingly expensive even for a turboprop

aircraft. Such an aircraft might consume about

4,000 gal (27,000 lb) of jet fuel per hour. At the

present price of $1.1 7/gal, the fuel costs to

maintain 75 aircraft (150 MX missiIes) in the air

24 hours per day, 365 days per year, would be

$3 billion annually. Thirteen years of deployment (the average of 5 years of start-up and 10

years of full deployment) would mean a contribution of $39 billion to Iifecycle cost from fuel

alone. Maintenance and crew costs would also

be high.

The total Iifecycle cost of a continuously

alert air mobile system is estimated in the

Costs section to be in the neighborhood of $90

billion (fiscal year 1980 dollars) even without

provision for postattack endurance. This cost

exceeds that of other basing modes by about a

factor of 2.
Ch. 6—Air Mobile MX 221

Dash-on-Warning With “Endurance”

This concept calls for aircraft maintaining

continuous ground alert at airstrips in the Central United States. A large number of additional airstrips is provided throughout the

country for the aircraft to land and refuel in

the postattack period.

A force of 150 aircraft, each carrying a

single MX missile, would require 50 or more

airfields, since the escape timeline would not

permit them to line up and wait their turn to

take off. Single airstrips wide enough to allow

two aircraft to take off simultaneously in opposite directions would be ideal. Basing at

least 700 nautical miles (nmi) from U.S. coasts

would seek to keep the aircraft as far as possible from Soviet submarines. If the air mobile

force were not to displace other Strategic Air

Command alert aircraft nor be collocated with

urban areas, some new airfield construction

would be required. The airfields need not all

be major airbases: most could be relatively

austere runways with modest support equipment, with major maintenance performed at a

few main operating bases.

Assured survival of a large fraction of the

force against a large Soviet SLBM force deployed near U.S. shores would require high

alert procedures. Since the difference between

survival and destruction would be measured in

minutes, the crews would have to be prepared

to start engines immediately on receipt of a

warning message. This preparation might mean

stationing the crews in the cockpits at all

times, a duty that some could find unattractive. Procedures calling for takeoff in response

to a first warning message (not waiting for confirmation) would also imply a willingness to

assume the consequences of an occasional

false alarm dispersal of the aircraft, carrying

their propellants and nuclear warheads. If the

aircraft were capable of launching their missiles only while airborne, dispersal in time of

crisis could be interpreted by the Soviets as

preparation for a first strike.

Most studies of air mobile MX have considered providing a large number of austere

airstrips dispersed about the country for the

aircraft to land, refuel, and await further

orders in the postattack period. The number of

airstrips of sufficient length, width, and hardness to accommodate aircraft of air mobile

MX size is in the hundreds, whereas the number of Soviet ICBM RVS that could destroy

them in the first half hour of the war is in the

thousands. It is therefore plain that the air

mobile force could not expect to find airfields

for postattack endurance unless their number

approximated or exceeded the number of

Soviet RVS. The “austere” postattack airfields

would have to be widely spaced in order that

fallout from an attack on one field did not prevent the aircrews from remaining at adjacent

fields for the hours or days of postattack endurance sought by building them. Providing

4,600 “austere” fields – equal to the number of

aimpoints in the baseline MPS system — could

result in a cost of about $30 billion to $40 billion to the air mobile deployment (see Costs

section). If the airstrips were spaced 25 miles

apart, 4,600 of them wouId entirely cover the 3

million mi 2 of the continental United States.

The question of postattack endurance is discussed further in the Endurance section.

If construction of a large number of austere

fields were contemplated, it would be desirable to minimize costs by deploying aircraft

capable of using short runways. Several studies

have discussed advanced medium short takeoff (AMST) aircraft capable of carrying one MX

missile. “Stretched” versions of the YC-14/15

have been considered as AMST candidates,

but these aircraft were not originally intended

to carry loads as heavy as the MX missile. The

resulting designs called for rather extensive

modifications and for runway lengths somewhat in excess of those normally considered

for the AMST.

Dash-on-Warning Without “Endurance”

(Base Case Air Mobile System)

Considerable cost savings could be achieved

by abandoning the requirement for a large

number of austere airfields for use in the postattack period. Since runway length would no

longer be critical, conventional wide-bodied

jets could be used, meaning that each aircraft
222 ● MX Missile Basing

could carry two MX missiles. Such a force

could use civilian or military airports for postattack operations or, if these airfields were destroyed, adopt a policy of “use it or lose it” for

the few hours of unrefueled flight time. The

implications of such a policy are discussed further in the Endurance section.

Where it is necessary to be explicit in the following, a Boeing 747 will be assumed as the air

mobile carrier. A Lockheed C5 could also be

used. A suitably modified 747 capable of carrying two 150,000-Ib MX missiles and their support equipment would have a takeoff gross

weight of about 900,000 lb and carry 200,000 lb

of fuel at takeoff. The aircraft would have an

unrefueled flight time of 5 to 6 hours and a

range of 2,000 to 2,500 miles. The missiles

would be carried one behind the other along

the length of the fuselage, and a “bomb bay”

would have to be provided in the aft fuselage

for dropping the missiles out at launch. Since

many commercial airlines are presently phasing some 747s out of their fleets, it is conceivable that used aircraft could be procured

and modified for the air mobile mission. Since

the aircraft would rarely fly, there might not be

any need to have new ones.

SURVIVABILITY

In comparison to other basing modes, air

mobile has the attractive feature that its prelaunch survivability would be relatively insensitive to the size and nature of the Soviet ICBM

force. During the half hour it would take

Soviet ICBMS to arrive on the United States,

the air mobile aircraft could have dispersed to

an area so large that a barrage attack consisting of thousands of equivalent megatons

would not destroy a majority of the aircraft.

The outcome of such an attack would furthermore be insensitive to the number of warheads

deployed on each Soviet booster and independent also of missile accuracy. Thus, air

mobile deployment would remove all advantage to Soviet fractionation and accuracy improvements even if the Soviets were to contemplate a massive barrage attack on the Central United States.

The true threat to a dash-on-warning air

mobile force would come not from the Soviet

ICBM force, but from SLBMS, that have a flight

time about half that of ICBMS when fired from

near U.S. coasts. The area into which the aircraft could disperse in this time would be

much smaller than the area they would cover

at the end of a half hour, since the first few

minutes would be consumed by receipt of the

warning signal, engine start-up, taxiing, and initially low-speed flight. Still, SLBM attack

would require a relatively large number of

Soviet submarines deployed near to U.S.

shores. The present Soviet SLBM force is incapable of such an attack. Thus, air mobile

basing would stress Soviet strategic forces

where they would be least able to respond in

the near term.

An air mobile force could therefore be

highly survivable. However, the difference between survival and destruction of the force

would be measured in minutes and would depend on receipt of reliable, timely tactical

warning and high alert procedures. An air

mobile ICBM force would share this sensitivity

with the bomber force. Moreover, if the aircraft were unable to find airfields to land and

refuel in the postattack period, their “survival”

would be limited to the first few hours of the

war.

There are many uncertainties regarding survival of aircraft to nuclear effects, and the

results of calculations are in certain respects

sensitive to the assumptions, but the overall

trends support the generalizations made

above.

Aircraft Vulnerability to Nuclear Effects

Little of a definite nature is known about the

effects on aircraft of nearby nuclear detonations. At low altitudes the dominant kil l

mechanism is probably the blast wave from
Ch. 6—Air Mobile MX | 223

the detonation and especially the gusting

winds that follow the shock front. These gusts

could damage extended surfaces such as the

wings and vertical stabilizer or cause engine

stalling. Such effects would clearly depend on

the orientation of the aircraft relative to the

position of the detonation. At low altitudes

(when escaping from their airfields) the aircraft

would be below the “Mach stem” or point on

the blast front below which the initial blast

wave and the blast wave reflected from the

Earth coalesce. For the low overpressures of

relevance to aircraft, there is some uncertainty

in modeling the front below the Mach stem.

These uncertainties could result in rather large

variations in the kill radius for aircraft of a

given nominal hardness. It is also necessary to

take into account the time elapsed between

the detonation and the arrival of the shock

front at the in-flight aircraft. All considered, a

range in hardness from 1 to 3 pounds per

square inch (psi) is probably appropriate.

At higher altitudes, the thermal radiation

emitted by the detonation is probably lethal to

the aircraft at a greater range than the blast

wave. As the altitude increases, a smaller fraction of the weapon yield appears as thermal

radiation, but since the air is thinner the radiation is attenuated less rapidly. The radiation is

also deposited in a shorter time at high altitude. Melting or buckling of aerodynamic surfaces could result. The effects could again depend on the orientation of the aircraft with respect to the detonation. Thermal fluences of

20 to 40 calories per square centimeter (cat/

c m

z

) or so are probably the limit for conventional aircraft with aluminum surfaces, but

thermal hardening (at some weight penalty)

could conceivably increase the thermal hardness as high as 100 cal/cm2

. An optimum cruise

altitude, considering both blast damage at low

altitudes and thermal flash at high altitudes, is

probably 10,000 to 15,000 f t.

In addition to the immediate damage done

by blast and thermal radiation, an air mobile

force could also be affected by electromagnetic pulse (EM P), dust lofted by ground

bursts, and crew radiation dose.

EMP would not affect crews or airframes,

but could disrupt electronic equipment. There

is a considerable amount of effort to harden

other military aircraft to EMP, and it appears

that with sufficient testing and attention to

design details, the risk of disruption can be

minimized.

Impairment of several aircraft flying

through the dust cloud caused by the Mount

St. Helens’ eruptions has raised concerns for

similar effects on aircraft operating after a

nuclear attack involving a large number of

groundburst weapons. Up to one-third of a million tons of dust per megaton of weapon yield

could be lofted into the altitude range between 40,000 and 60,000 ft. Though aircraft

would operate below this altitude, considerable dust densities could exist at lower altitudes for long periods of time as the dust at

higher altitudes settled. Turboprop aircraft

might fare better than conventional jet aircraft

in these circumstances. However, this area is

one of considerable uncertainty.

At the ranges from detonation where the aircraft itself would survive, the prompt radiation

dose delivered to the aircrews would probably

not result in mission-impairing sickness. If the

aircraft were required to remain at austere

fields subject to local fallout in the postattack

period, however, there could be some danger

of mission-impairing doses unless care was

taken in the choice of airstrips.

In the illustrative calculations that follow, it

will be assumed that, for a reference yield of

1.5 MT, the lethal radius for an aircraft at low

altitude (during escape) is about 8 miles and at

cruise altitude (10,000 to 15,000 ft) about 6

miles. These ranges correspond roughly to aircraft hardened to 1 to 3 psi overpressure and

40 cal/cm

2 thermal fluence. It should be

remembered that there are considerable uncertainties in such calculations.

ICBM Barrage of In-Flight Aircraft

If the Soviets contemplated ICBM barrage

attack on in-flight aircraft, either a continuously airborne force or a dash-on-warning force,
224 ● MX Missile Basing

expenditure of considerable megatonnage

would be required to destroy an appreciable

number of aircraft. optimum burst height

. would be at the aircraft cruise altitude (10,000

to 15,000 ft, as discussed above). The outcome

of such an attack would be insensitive to both

weapon accuracy and fractionation of missile

payload, as discussed further in chapter 8. Because of the burst height, there would be I ittle

prompt fallout and less damage to ground

structures than for near-surf ace bursts.

Attack On Continuously Airborne MX Fleet

Five thousand l-MT weapons could destroy

all aircraft within an area of about 600,000 miz

.

Since a continuously airborne air mobile fleet

could be dispersed over an ocean area totaling

millions of square miles, even a very large attack could not significantly reduce the force.

If the aircraft could be tracked continuously

(methods for tracking are discussed below),

and the Soviets could retarget their ICBMS

continuously on the basis of up-to-the-minute

aircraft locations, the aircraft could travel far

enough in the half-hour ICBM flight time to

escape direct attack. For instance, if an aircraft cruised at 400 mph, at the end of a half

hour it could conceivably be anywhere within

a circle of area 130,000 mi z about the point

where it was located when the ICBMS were

launched. A full 1,000 MT would therefore be

required to destroy it with certainty.

Attack On Dash-on-Warning Fleet

Within a half hour of takeoff, a fleet of air

mobile aircraft located at bases within the

north-central region of the United States at

least 700 nmi from the coasts could be dispersed over an area totaling about 1 million

m i

2

. The Soviets could therefore destroy about

one-eighth of the force (perhaps 20 or so MX

missiles) for each 1,000 MT expended. Destruction of a sizable fraction of the force would

therefore require an enormous expenditure of

megatonnage. It is not clear that such an attack would in any case be appealing to the

Soviets in all circumstances, implying as it

would (for the low cruise altitude assumed)

widespread destruction in the entire Central

United States.

Advanced Threats to Airborne Aircraft

It is possible to imagine several means by

which in-flight aircraft over the United States

could be tracked continuously by Soviet sensors. All of these means would be subject to

U.S. countermeasures. Since, as described

above, even continuous retargeting of ICBMS

on the basis of up-to-the-minute knowledge of

aircraft locations could be unprofitable if the

aircraft speed were high, exploitation of a continuous tracking capability would require that

the ICBMS be able to be retargeted in flight.

This brief section describes some of the means

to track aircraft and the possibilities for inflight correction of ICBM trajectories. However, even if in-flight correction were feasible,

Soviet dependence on any such strategy for attacking air mobile MX would entail risk and be

subject to U.S. countermeasures.

Probably the easiest means to identify and

track aircraft would be to direction-find on

their radio emissions. To counter this threat, an

air mobile force could observe radio silence

whenever possible and stagger broadcasts so

that all planes could not be located simultaneously. Above all, it could use communications not susceptible to intercept.

Large over-the-horizon radars based in Cuba

could probably maintain coverage of the entire United States but would not be able to

localize aircraft well enough to support effective retargeting. They would also be susceptible to jamming. Space-based radars would

have to be relatively large in number, would

have difficulty with ground-clutter background, and could be jammed. It might be possible to locate the aircraft by intercepting

refIected signals from the Federal Aviation Administration radar network. Receivers used for

this purpose might be jammable.

Space-based short-wave infrared sensors

could attempt to observe the hot exhaust gases

from aircraft engines, but the power levels

wouId be exceedingly low, especialIy if the air-
Ch. 6—Air Mobile MX . 225

craft cruised at low altitudes. Means to cool

and diffuse aircraft exhaust are also possible.

Long-wave infrared sensors would seek to observe the cool body of the aircraft against the

warm earth. Again, this technique would be

difficult in the best of circumstances and

couId be defeated by emissive body paints and

heaters in the skins of the aircraft. All infrared

devices could be defeated by cloud cover. if

the aircraft cruise altitudes were in the 10,000-

to 15,000-ft range, average U.S. cloud cover

might obscure about a third of the force at any

given time.

Since jet aircraft could travel about 200

miIes in a half hour, substantial trajectory corrections would be required if an RV were to be

retargeted during flight to an impact point near

the aircraft. A maneuverable reentry vehicle

could not make this large a correction using

aerodynamic maneuvers. Midcourse velocity

corrections of a few thousand feet-per-second

would be needed for ballistic RVS. The link

from the sensor tracking the aircraft to the inflight RV could be jammed. Significant payload penalties (at least 50 percent) would also

result from the need for receiving equipment

and active propulsion.

SLBM Attack On Dash-on-Warning

Air Mobile

Attack on the alert airstrips from Soviet submarines deployed near U.S. coasts would be

the principal threat to a dash-on-warning air

mobile fleet. Calculations indicate—given the

usual uncertainties in such estimates— that the

force would be highly survivable even against

a rather advanced future Soviet SLBM deployment consisting of large numbers (20 or more)

of Soviet submarines stationed very near to

U.S. coasts, provided high alert procedures

were adopted for the force.

The most important factors influencing the

survivability of an air mobile force would be

the procedures adopted by the United States

to ensure rapid takeoff in the event of attack

and the size and deployment of a future Soviet

SLBM force. These factors establish the important trends. The precise numerical results also

depend on aircraft hardness to nuclear effects,

the way the Soviet attack was structured (laydown pattern, height of burst), the flyout pattern of the aircraft (range, altitude, and direction from airstrip as a function of time), and

the distribution of escape airstrips with respect

to distance from the coasts. The outcome of

any calculation should be viewed with these

sensitivities and uncertainties in mind.

Alert Procedures

It would be crucial to the survivability of air

mobile that the time between Soviet SLBM

launch and aircraft brake release be as short as

possible. This time would be the sum of the

times to receive warning of Soviet attack, man

the aircraft, and bring engines up to speed. As

discussed more fully in the Support Systems

section and chapter 4, it should be technically

feasible to provide reliable warning sensors

that would indicate SLBM launch within at

least 1 minute. It would be possible to station

crews in the cockpits of alert aircraft at all

times, though this type of duty might well be

unattractive to the crews. A jet engine can be

started and brought up to speed in somewhat

more than 1 minute.

Thus, a “breakwater to brake release” time

delay of between 2 and 3 minutes is feasible,

though perhaps optimistic.

Such an extreme alert posture could result in

an occasional false alarm dispersal of aircraft,

carrying their potentially explosive (at least in

the nonnuclear sense) payloads. Public acceptance of this possibility wouId be important in

maintaining this posture in the long term. If

time-consuming procedures were instituted to

double-check the accuracy of the warning

message before the aircraft took off, survivability against surprise attack could be significantly reduced.

If the aircraft were able to launch their missiles only while airborne, such a false alarm

dispersal could appear to the Soviets to be

preparation for a U.S. first strike.
226 ● MX Missile Basing

Soviet SLBM Forces

Attack on air mobile would require large

numbers of SLBMS

- deployed near to U.S.

coasts. The effectiveness of an attack would

depend on the number of SLBM missiles

launched but would be quite insensitive to

how the payloads were fractionated into RVS

and to RV accuracy. Effectiveness would also

depend on how close the submarines were able

to approach to U.S. shores and the types of trajectories they fIew.

In order to destroy an appreciable fraction

of the air mobile force, the Soviets would have

to deploy a large number of submarines near

to U.S. coasts and launch their missiles on

special fast trajectories. The present Soviet

SLBM force is incapable of such an attack.

Soviet dedication of a future SLBM force to attacking a U.S. air mobile force could compete

with other time-urgent missions involving both

U.S. and European targets. It is also unlikely

that the approach of large numbers of Soviet

submarines to U.S. coastlines would go undetected. Short-term U.S. responses to such a

“surge” could include diplomatic remonstrance, increased antisubmarine warfare efforts, and very high (perhaps even continuously airborne) alert procedures.

Illustrative Calculations

Figure 89 shows the result of a typical calculation of air mobile survivability. The graph

shows the fraction of the air mobile force surviving an attack plotted against “escape

time’ ’–the number of minutes the aircraft had

to fly away from their bases (measured from

brake release) before incoming SLBM RVS arrived to destroy them. The earlier the aircraft

responded to a warning signal, the longer the

escape time would be; the shorter the SLBM

flight time (depending on the range and the

type of trajectory), the shorter the escape time.

(The precise assumptions made in constructing figure 89 are: 747 flyout; simultaneous

takeoff of two aircraft per base in opposite directions; about 8 equivalent megatonnage

(EMT) targeted at each base; nominal aircraft

hardness of 2 psi; inland basing.)

Figure 89.—Survivabilit y v. Escape Time

(8 EMT on each airstrip, 2 psi aircraft)

t 1

80

80

40

20

0 1 1-

0 1 2 3 4 5 6 7 8 9 10 11 12

Aircraft escape time before arrival of SLBM attack (minutes)

SOURCE: Office of Technology Assessment.

The curve in figure 89 begins at very low values (most aircraft destroyed) and climbs rapidly to rather high values (most aircraft survive). Whether the aircraft survived an attack

or not would clearly be a matter of a very few

minutes.

Where the outcome of a given attack fell on

the curve of figure 89 would depend on the

Soviet SLBM deployment. The various possibilities–launch from offshore patrol areas (hundreds of miles from U.S. coasts) or from positions at the coasts, on normal or special fast

trajectories—would result in the approximate

values shown in figure 90 for the survivability

of the air mobile force. Figure 91 shows the

resuIt of delaying takeoff by 2 1\2 minutes,

either because crews were not stationed in the

cockpits or because confirmation of warning

was required before takeoff. Figure 92 shows

the effect of increasing the size of the attack

(measured in EMT) on each alert airstrip.

Figure 93 shows the combined effects of both

delayed takeoff and increased attack size.

Finally, in figure 94, takeoff is delayed and the

attack size increased, but the aircraft hardness

is also increased from a nominal value of 2 to 5

psi.

These figures support the following conclusions:

● The dash-on-warning force would be highly survivable against all attacks except

those involving fairly large numbers of

SLBMS launched on fast trajectories from

positions actually at the U.S. coastline.
Ch. 6—Air Mobile MX . 227

w

c. -

. -

:

3

U)

Figure 90.—Aircraft Survivability y During

Base Escape

8 EMT per airstrip

2 psi aircraft

Prompt takeoff

1001 1

I

. . I

I I

1

Off coasts Off coasts At coasts

normal fast normal

trajectory trajectory trajectory

Soviet submarine deployment

SOURCE: Office of Technology Assessment.

At coasts

fast

trajectory

Figure 91 .—Aircraft Survivability During

Base Escape

8 EMT per airstrip

2 psi aircraft

Takeoff delayed 2.5 minutes

Off coasts Off coasts At coasts At coasts

normal fast normal fast

trajectory trajectory trajecto~ trajectory

Soviet submarine deployment

SOURCE: Office of Technology Assessment.

Figure 92.—Aircraft Survivability y During

Base Escape

14 EMT per airstrip

2 psi aircraft

Prompt takeoff

g loo~

.k

a

‘5

Off coasts Off coasts At coasts At coasts

normal fast normal fast

trajectory trajectory trajectory trajectory

Soviet submarine deployment

SOURCE: Office of Technology Assessment.

Figure 93.—Aircraft Survivability y During

Base Escape

14 EMT per airstrip

2 psi aircraft

Takeoff delayed 2.5 minutes

75

50

25

Off coasts Off coasts At coasts At coasts

normal fast normal fast

trajectory trajectory trajectory trajectory

Soviet submarine deployment

SOURCE: Off Ice of Technology Assessment
228 ● MX Missile Basing

c

.0-

Gm

t

100

75

50

25

Figure 94.—Aircraft Survivability During ●

Base Escape

14 EMT per airstrip

5 psi aircraft ●

Takeoff delayed 2.5 minutes

●

The effect even of this rather advanced

threat could be offset somewhat by high

alert procedures.

Significant aircraft hardening, if feasible,

would restore high survivability even in

the face of an advanced threat.

Further airfield construction, so that there

was one airstrip per aircraft (or even several, with the aircraft moving among them

frequently), would, by decreasing the EMT

applied to each, improve survivability in

the face of a large SLBM deployment.

Off coasts Off coasts At coasts At coasts

normal fast normal fast

trajectory trajectory trajectory trajectory

Soviet submarine deployment

SOURCE: Off Ice of Technology Assessment.

ENDURANCE

If the air mobile force survived the initial attack, it would only be effective for the first few

hours of the war unless provision were made to

land and refuel the aircraft. The unrefueled endurance of the aircraft would be 5 to 10 hours,

depending on the type. This time could be

more than doubled with in-flight refueling, but

a fleet of tankers with its own escape airstrips

would have to be provided for this purpose. If

airfields capable of at least minimal support

were not available at the end of this period,

the National Command Authorities would be

in a position of “use it or lose it” with respect

to the air mobile ICBM force. Attempting to

ensure endurance for an air mobile force could

therefore be a critical problem and, if addressed by constructing a large number of

recovery airstrips, a major cost driver.

A first possibility for postattack reconstitution would be use of the several hundred existing military and commercial airfields throughout the U.S. with runways long enough for the

large MX missile carriers. Soviet ICBMS could

easily destroy these airfields within the first

half hour of a war. Whether the Soviets would

choose to do so in all circumstances is another

matter, since most of these airfields are near

large urban areas. Nonetheless, attack on all

would clearly be possible at relatively low cost

to the Soviet RV inventory.

It should be noted that whether additional

postattack airfields were provided or not, the

Soviets would have to attack the existing commercial airfields if they wished to deny endurance to the U.S. force. Thus, construction

of additional airfields could not be justified on

the grounds that failing to do so would invite

attack on all the Nation’s airports: the very existence of these airfields, sufficient by themselves to support air mobile in the postattack
Ch. 6—Air Mobile MX ● 229

period, would make them targets no matter

what else the United States built. Independent

of whether extra recovery airstrips were built,

air mobile deployment would face the Soviets

with the choice of attacking a large number of

urban/industrial targets (and forcing the

United States to a “lose it or use it” posture) or

granting endurance to the U.S. force.

A second approach to endurance would be

to construct a large number of “austere” or

minimalIy equipped recovery airstrips throughout the United States. These airstrips would

have to have at least an adequate runway and

fuel supply. They would have to be spaced far

enough apart so that fallout from attack on

one would not make it impossible for aircraft

crews to remain at neighboring airstrips for the

hours or days of postattack endurance sought

by building them. It would also be desirable, if

not necessary, to equip each field with landing

aids (beacons or radar reflectors) and perhaps

also crew shacks, floodlights, fences, snowplows, and the like. Equipping each of thousands of airfields with such provisions would

be exceedingly expensive. Alternatives could

include providing road-mobile recovery teams

to meet the aircraft at the recovery sites or providing a fleet of aircraft loaded with supplies,

on alert like the missile fleet, to accompany

the aircraft.

A serious effort to build more austere recovery sites than the Soviets possessed RVS to destroy them would be enormously expensive

and completely impractical if the Soviet threat

grew large. There are about 2,300 airfields in

the United States with runways 2,500)-ft long

and 40-ft wide, that are of medium hardness.

Most of these fields are wholly inadequate to

support aircraft the size of MX carriers and

would need substantial improvement. Construction of an additional 2,300 recovery

fields, to make a total of 4,600 (the number of

aimpoints in the baseline MPS system), would

be much more expensive still. If these recovery

fields were located 25 miles from one another,

they would cover the entire 3 million mi2 of the

continental United States. If the numbers were

made larger still, the packing couId be so close

that attack on one could make neighboring

fields unusable.

It would thus be impossible to guarantee

postattack endurance for an air mobile MX

force against a large Soviet threat. As a practical matter, it would only be possible to force

on the Soviets the choice of granting endurance to the U.S. force or attacking a large

number of targets spread throughout the country. How many airfields, if any, the United

States constructed would thus seem to depend

on what number, if any, would induce the Soviets to give up targeting them. Alternatively, the

United States could take the position that if

the Soviets were willing to attack sites throughout the United States, the United States would

be willing to adopt a “use it or lose it” posture.

In this case the number of recovery airfields

built would be decided according to the

amount of damage the United States would

tolerate before such a posture became acceptable to U.S. policy makers.

There could conceivably be some value in

having more airfields suitable for air mobile

operation than the Soviets had SLBM RVS.

These airfields could be useful if the U.S.

doubted the reliability of its SLBM warning

sensors, wished to relax the force’s alert

posture, or were somehow “spoofed” into dispersing the air mobile fleet. If the number of

dispersal fields were larger than the Soviet

SLBM inventory, a force that in a crisis moved

randomly and frequently among them would

have a measure of survivability even in the

absence of warning of SLBM attack. ICBM RVS

arriving in larger numbers a short time later

than the SLBMS could stilI destroy the force, so

the dependence on warning would still not be

wholly removed. Transit to a “hop and sit”

posture would also allow some relaxation of

alert procedures, alleviating the fear that

takeoff in response to a false warning message

(there being no time for confirmation) could be

mistaken by the Soviets for preparation for a

U.S. first strike (since the missiles could only

be launched while airborne). Last, the aircraft

would be vulnerable when they had to land following a “spoof” or small attack designed to
230 ● MX Missile Basing

cause them to take off. A large number of mal circumstances. It is possible that some

landing sites would make attacking the portion stretches of Midwestern highway could be

of the fIeet grounded at any one time as costly used, but fuel caches and support equipment

as possible to the Soviets. would have to be prepositioned or brought to

Another possibility for recovery sites would the landing sites by road mobile vehicles

be along stretches of the Nation’s highways. (themselves subject to attack).

Since M-X-sized missile carriers would need Endurance could clearly be a major problem

long and wide stretches of highway to land and for air mobile MX. The next section estimates

take off, it might not be practical to depend on the cost of providing large numbers of recovthis method. The traffic density on most U.S. ery airstrips.

highways is prohibitively high, at least in norCOSTS

OTA has not performed detailed cost analyses for the three air mobile MX configurations

discussed in this chapter. What follows are

rough estimates that seek to indicate overall

orders of magnitude and to highlight the cost

drivers. These estimates are based on air mobile MX analyses done by other Government

agencies. However, since the outcomes are

very sensitive to assumptions concerning the

number and cost of aircraft and airfields, etc.,

these analyses could only provide a guide to

the costs of the systems described here. The

final results provided here probably reflect the

true costs of the systems described to about 10

to 20 percent. Costs quoted are nominally in

fiscal year 1980 dollars. These costs do not include the systems described in the Support Systems section nor the possible additional costs

of hardening aircraft. Larger or smaller deployments than those considered here could lead

to substantial changes in system costs.

Continuously Airborne

This system would consist of 75 new large

turboprop aircraft (150 MX missiles) continuously airborne and operating out of four new

coastal main operating bases. Costs might be:

Aircraft: 75 patrol aircraft plus 50 for training

and attrition, each costing $80 million (including development costs): $10 billion.

Missiles: missiles modified for air launch, including spares and test missiles: $12 billion,

including development.

Bases: Four main operating bases: $4 billion.

Operations, excluding fuel: $2 billion per year

for 13 years (average of 5 years of startup

and 10 years of full deployment): $26 billion.

Fuel: Round-the-clock flight of 75 aircraft at

$1.17 per fuel gallon for 13 years: $39 bilIion.

Total: $91 billion.

Dash-on-Warning With “Endurance”

This concept consists of 150 AMST aircraft

(carrying 150 MX) on continuous ground alert

at 75 inland airfields. Also provided are 2,300

to 4,600 recovery airfields. Three cases are

considered:

●

●

●

Case A: Minimal upgrades to 2,300 existing airfields, including hard gravel lengthening and fuel caches.

Case B: Same fields as case A with addition of landing aids, floodlights, security

fence, snowplow, crew shack, 2-man permanent crew, and other supplies.

Case C: Additional 2,300 airfields built

from scratch and equipped as in case B.

Aircraft: 85-percent reliability implies 180 alert

aircraft plus another 50 for training and attrition at $50 million each: $12 billion.

Missiles: As above, $12 billion.

Alert bases: 75 Central U.S. airfields, including

some existing joint civilian/miIitary airports, with 6 main operating bases: $4 billion.
Ch. 6—Air Mobile MX ● 231

Operations (1 3-year average):

Case A: $18 billion.

Case B: $24 billion.

Case C: $28 billion.

Recovery airfields:

Case A: $4 billion.

Case B: $10 billion.

Case C: $25 billion.

Total:

Case A: $50 billion.

Case B: $62 billion.

Case C: $87 billon.

fields. No provision is made for postattack endurance.

Aircraft: 85-percent reliability implies 90 alert

aircraft plus another 40 for training and attrition, at $60 miIlion each: $8 billion.

Missiles: As above, $12 billion.

Alert bases: 38 Central U.S airfields, 4 main

operating bases: $3 billion.

Operations: 13 years: $77 billion.

Total: $40 billion.

Dash-on-Warning Without “Endurance”

This concept consists of 75 wide-bodied aircraft (150 MX) on ground alert at 38 inland airSUPPORT SYSTEMS

Warning Sensors

The survival of a dash-on-warning air mobile

MX force would be critically dependent on receipt of prompt, reliable warning of Soviet

SLBM launch. As discussed more fully in the

context of launch under attack (ch. 4), it would

be technically feasible with cost and continued

effort to provide a variety of tactical warning

systems which, taken together, wouId be exceedingly difficult for the Soviets to disrupt.

These warning sensors could include high-orbit

short-wave infrared satellites, ship-based and

coastal radars (the latter defended with a

“threshold ABM” if desired), and airborne infrared sensors and radars. It would also be

technically feasible, again with cost and effort,

to secure the communications links from the

sensors to command posts and from command

posts to the alert airfields.

Clearly, if the required money and effort

were not dedicated to providing such warning

sensors, a force that depended for its survival

on a very few minutes of escape time would be

endangered. No matter how much money and

ingenuity were devoted to designing safeguards for the air mobile warning sensors, and

even if these safeguards were very robust indeed, it would probably never be possible to

eradicate a lingering fear that the Soviets

might find some way to sidestep them.

Public acceptance of the possibility of false

alarm dispersal of the fleet wouId be essential

to preserving a high alert rate in the long term.

If the aircraft could only launch their MX missiles when airborne, false alarm disposal could

be mistaken by the Soviets for preparation for

a first strike.

Command, Control, and

Communications (C3

)

A C3 system capable of supporting the complex force management needs of an air mobile

force would entail relatively low risk but could

be quite costly. After dispersal, the aircraft

would need to report their status [fuel remaining, missile readiness, etc. ) to a central airborne command post and exchange information concerning the location and status of surviving recovery airfields. If a fraction of the

force had been destroyed, there could be a

need to exchange targeting information to ensure adequate target coverage.

While airborne, line-of-sight communications among aircraft via UHF would be possible at ranges up to about 300 miles. A UHF
232 MX Missile Basing

“relay” from all aircraft to the command post

could be established. Adaptive high frequency

and very low frequency/low frequency could

also be used. If the aircraft were dispersed at

many recovery fields throughout the United

States in the postattack period, some form of

satellite communications would be highly

desirable. High-orbit extremely high frequency

satellites such as described in other chapters

would provide survivable, high data-rate

satellite communications to small, trainable

dish antennas.

Missile Guidance

Since the MX missile would be on a mobile

platform for up to several hours before launch,

accuracy would degrade relative to stationary

deployment unless additional measures were

taken. These measures might take several

forms.

The most accurate would be external update, such as by the GPS or CBS that would

provide position and velocity update to the

missile’s guidance system during cruise or

during boost. Accuracies could be made comparable to land-based accuracies for update

during cruise and better for update during

boost. The main disadvantage of these methods would be reliance on the survivability of

the external aids. Secondly, in a nuclear environment the update information might not

be transmitted through the ionosphere. This

problem could degrade accuracy by 25 to 50

percent; however, the precise amount is uncertain.

A second method, that would be self-contained to the missile and aircraft, would be to

use a detailed map of gravity disturbances and

a high-class inertial measurement unit (IMU),

such as the Advanced Inertial Reference

Sphere in the missile. Such gravity mapping

would be compatible with mapping programs

utilizing SEASAT and GPS. Gradiometers

might be more applicable to this method in

their present state of development than to realtime navigation. Resulting accuracies might be

some 70 percent degraded relative to landbased MX.

Finally, doppler radar and a high-class IMU,

without external aids or gravity map compensation, might give the missile a circular error

probable in the range 2,000 to 2,500 ft.
Chapter 7

SURFACE SHIP BASING OF MX
Chapter 7.— SURFACE SHIP BASING OF MX

Page

overview ......, . . . . . . . . . . . .. ...235

Factors Common to All Designs 23 5

System Description . . 236

Operational Considerations . . .23 8

Soviet Data Collecting Activities Relevant

to the Vulnerability of MX-Carrying

Ships . . . . . . . . . . . . . . . . . .. ..239

Threats to MX Surface Ships. . .240

Continuous Trailing . . . . .240

“Delousing” of Trailers at Port Egress. .244

At Sea “Delousing” of Trailers . . 244

Reacquisition of Trailed MX Ships 2 4 5

Regions of Poor Visibility weather. 246

Final Comments on Trailing 247

Other Surveillance Technologies . 24 7

Over-the-Horizon Kaclars 247

Satellite-f Borne Sensors . . . . .248

MX Requirements and Surface Ship Fleet, . 250

Accuracy of Surface-Ship-Based MX 251

Responsiveness of a Surface Ship Force 2 5 2

Flexibilit y . . . .

Enduranc e 2 53

Cost and Schedule 253

TABLE S

Table No. Page

30 Number and Displacement of Ships

in the World 239

31

32

33

Operational Factors Affecting Fleet of

Soviet Trailing Vessels . ............241

SL-7 Specifications . . . .............254

10-Year Lifecycle Cost. . ............254

95

96

97

98

99

100

101

102

103

104

105

106

107

108

109

110

Topside Arrangements . . . . . .236

Surface Ship Deployment Area. . . . .238

Speeds of World’s Merchant Ships .. .239

Displacements of World’s Merchant

Ships . . . . . . . . . . . . . . . . . . . 2.39

Trailing Cycle Against MX-Carrying

Surface Ships. . . . . . . . . . . . . . ......242

Geometry of Barrier Outside a Port

With Unobstructed Access to the Sea .243

Geometry of Barrier Outside a Port

With Obstructed Access to the Sea. .. 243

Loss of Trail Probability Event Tree. . .246

Regions Where Visibility is Often Poor 246

Geometry of Over-the-Horizon Radar 247

Radar Cross Sections of Two Similar

Looking Ships at Different Over-theHorizon Radar Frequencies. . . .248

Ground Track of Surveillance

Satellite in a 24-Hour Period . .......248

Observation Swath of Surveillance

Satellite. . . . . . . ................24 9

Single Satellite Repeat Coverage of

Mid-North Atlantic in a 24-Hour Period 249

Precession of Observation Swath on

Two Successive Orbits of a

Surveillance Satellite . ............24 9

Search Schedule of Surveillance

Satellites at Mid-Northern Latitudes .. 250
Chapter 7

SURFACE SHIP BASING OF MX

OVERVIEW

The object of basing the MX missile on surface ships would be to attain survivability by

using both deception and large areas of ocean

to exhaust or overwhelm Soviet ability to trail

or maintain surveillance over the force. The

fleet of MX-carrying ships would attempt to

deceive Soviet trailers and sensors by looking

like typical merchant ships. By operating

within the 6,000- nautical-mile (nmi) range of

Soviet targets, they could hide in between 50

million and 60 million square miles (mi 2

) of

ocean. Since the ships would have to look like

merchant ships, they would not be fitted with a

launch pad. Instead, the ships would unload

missiles directly into the water, and fire them

from a floating position.

Surface ships appear attractive as a means

for deploying the MX because they are easy to

build. Therefore, if a policy decision were

made to deploy MX off land, it would be easier

to build a fleet of surface ships than a fleet of

submarines.

The choice of whether MX should or should

not be deployed at sea is a matter of policy.

Some of the views that argue for or against sea

basing are presented in the discussion of small

submarines (ch. 5).

In the discussion that follows, the features

of surface-ship basing that are common to the

concept are discussed first. Then a point design is presented and its survivability discussed. This section will be followed by a discussion of the accuracy, responsiveness, flexibility, and endurance that could be possible

with a system of MX-carrying surface ships. In

the final section, the cost

schedule wilI be presented,

and deployment

FACTORS COMMON TO ALL DESIGNS

Surface ships are large floating objects. Consequently they can be observed at very great

distances, under a wide variety of conditions,

by a wide variety of sensors. The long distances at which ships can be observed and the

ease of identification of ships create opportunities for very effective trailing operations as

well as for very effective wide area search.

This circumstance is fundamentally different

from that of submarines.

In order to compensate for the fact that

ships can be observed at great distances with

modern sensors, the ships would be disguised

to look like merchant ships and would patrol in

very large areas of the ocean. They would

sometimes mingle with other merchant ships in

busy shipping lanes and at other times they

would patrol in areas where Soviet surveillance is believed to be poor. The ships would

have a speed sufficient to outrun trailing trawlers and commercial ships, Iight defensive armaments, and electronic jamming and spoofing equipment.

A large fleet of MX-carrying surface ships

would pose a considerable threat to the Soviet

homeland and to Soviet strategic weapons systems. It could therefore be expected that the

Soviets would be unlikely to ignore such a

threat, and in response, might commit substantial resources to trailing and surveillance.

Since Soviet ships would have to make long

transits to and from home ports before attempting to trail MX-carrying surface ships,

this deployment would result in a considerable

expenditure of Soviet resources. This tactic

could create resource problems for the Soviets

and force them to divert resources from other

miIitary commitments.

The counter problem, from the American

point of view, is that confidence in the survivability of the surface ships would be low.

235
236 ● MX Missile Basing

There would be periods of time when the

weather in the Northern Hemisphere would

favor surveillance, tracking, and trailing. During these periods there would always be the

possibility that large fractions of the fleet

would be under surveiIlance or trail.

Under certain operational conditions, survivability of the force could depend on

maneuvering duals between the trailers and

the trailed ships. As adversaries developed

familiarity with each other’s operational procedures and capabilities, the initiative could

constantly shift from one force to the other.

The constantly shifting tactical momentum

between the different forces would have much

of the unpredictability of a classical “war at

sea” as forces maneuvered about, attempting

to maintain an advantage. This situation could

result in serious doubts in the minds of the

public and decisionmakers about the survivability of the force in times of crisis.

The result of this constantly shifting circumstance would be that the vulnerability and

the survivability of the fleet would constantly

fluctuate. If the fleet were vulnerable during a

time of crisis, a substantial incentive would exist to preempt before the opportunity was lost.

SYSTEM DESCRIPTION

The fIeet of MX-carrying surface ships would

be made up of 30 fast merchant-like ships with

movable superstructures, false hatches, and

movable cranes and booms (see fig. 95). This

equipment would allow them to change their

appearance and complicate the process of radar satellite tagging of the ships. The ships

would, in addition, be rigged with multiple sets

of navigation lights so they could be made to

change appearance to night observers. The

ships would be constructed of lengths varying

Figure 95.—Topside Arrangements

SOURCE: Office of Technology Assessment.

between 550 and 650 ft and would have a displacement of between 15,000 and 20,000 tons.

They would have an unrefueled-at-sea endurance of about 20,000 nmi assuming a patrol

speed of about 20 knots. The ships would also

have high-speed gas turbines in order to reach

the 30 + knot speeds needed to break trail.

The ships are assumed to have an at-sea rate

of about 80 percent (60 days at sea and 15 days

in port). Missile reliability, extended refits and

overhauls will result in a ship availability of

less than 80 percent. (See ch. 5 for and explanation of the effects of overhaul, extended refit,

and missile reliability on the availability of

ships. ) If survivability fell below 50 percent, it

would require an increase in the number of

ships if the fleet is to be able to maintain the

requisite number of survivable missiles on station. As will be demonstrated in the section on

survivability, an assessment aimed at optimizing the at-sea rate and overhaul rate is not

justified in light of the very large uncertainties

associated with survivability.

Each ship would carry 8 to 10 MX missiles so

that 200 MX missiles would be at sea at all

times. This total would be an adequate number

of MX missiles if the ships had a survivability .

rate of 50 percent. The conditions under which

such a survivability rate might be achieved are

discussed below in the section on survivability).
Ch. 7—Surface Ship Basing of MX ● 237

The ship would be equipped with TridentIike navigation and communications suites.

Antenna masts would be disguised to look like

normal merchant equipment or would be recessed so they could not be observed by aircraft, other ships or satellites. Jamming and

electronic countermeasure equipment would

also be available on the ship to aid in defense

and to help confuse potential trailers. In addition to the Trident inertial navigation system,

the ship’s navigation suite would be equipped

with a gravity gradiometer (assuming such

gradiometers are successfully deployable on

surface ships) and a system for interrogating

acoustic transponders.

The ships would also be equipped with a

sonar system that could be extended or withdrawn from recesses under the hull. This would

give the ship a modest active and passive sonar

capability against trailing submarines. It would

also be possible to mount a far more capable

sonar array on the bottom of the hull but this

would be observable to submarines or divers

and could be used as a means of “sorting”

ships while at sea or in port.

Since the ships would have to be indistinguishable from merchant ships, their acoustic

outputs would have to be comparable with

those of merchant ships. Since merchant ships

are considerably noisier than combat ships, it

would be considerably easier for a distant trailing submarine or surface ship to maintain contact with the aid of a passive sonar system

once the MX ship has been taken in trail.

The ships would have an onboard security

force to protect the missiles and nuclear

weapons in the event of an incident at sea.

This force would be armed with conventional

small arms and would also man the ships’

defenses. Defenses might include heavy machine guns, rockets, cruise missiles, and light

cannon. Perceived needs for heavier armaments would have to be balanced against the

need to maintain deception. Provision would

also be made for the destruction of the nuclear

weapons as a measure against the possibility

of a successful boarding.

A system of 150 acoustic transponder fields

would be secretly emplaced in the 50 million

to 60 million mi2 of the surface-ship deployment area. The transponder fields would make

it possible for the ships to obtain extremely accurate velocity and position information for

the missile guidance system prior to a launch.

I n the event of a need to use these transponder

fields, the ships could proceed at 30+ knots to

the nearest field. Fleet deployment to the

fields could be affected within 11 to 12 hours.

The MX missile guidance system could be

modified in a number of ways in order to

achieve high accuracy at sea. A minimal modification would involve the development of

software optimized for a purely inertial guided

sea-based MX. A more involved modification

of the guidance system would involve the use

of a star tracker in conjunction with the MX inertial measurement unit. Still another modification of the guidance system would involve

the use of radio beacons in conjunction with

the MX inertial measurement unit. These

methods of guidance, and their capabilities,

are discussed in detail in the section on submarine basing of MX.

An additional activity aimed at achieving

improved accuracy with the surface-shipbased MX would involve the measurement and

use of gravimetric data for the deployment

areas in which the ships operate. These data

would then be used to correct for gravitationally induced missile guidance errors along

flight trajectories.

The ships would deploy from two bases on

the east and west coasts of the continental

United States. These bases would have special

shore facilities for assemblage, storage, and

handling of MX missiles. In addition, explosive

handling loading docks would be constructed

so that damage from an accidental ignition or

explosion of rocket propellant would be limited to the loading facility.
238 MX Missile Basing

OPERATIONAL CONSIDERATIONS

The fleet of surface ships would operate in

an area as large as 50 million to 60 million mi2

(see fig. 96). There would be a goal of operating in as large an area as possible to decrease

the likelihood of surveillance. This goal would

be constrained by the need to stay within missile range of Soviet targets.

The ships would attempt to remain covert

using a variety of techniques. They would fly

the flag of the country of registration and

display the hull identification markers of a

merchant ship.

The pattern of deployment would take

advantage of shipping lanes, bad weather,

day/night cycles, and intelligence on Soviet

patrol activities. The ships would be in constant receipt of shore-to-ship very low frequency (VLF) signals. Since the ships would be

on the ocean surface, they could also monitor

shore-to-ship high frequency (H F) transmissions

and satellite transmissions on a continuous

basis.

There would be an operational need to report back to National Command Authorities

(NCA) on a regular schedule to prevent the

Soviets from attritting a large part of the fleet

without U.S. knowledge. In addition, there

Figure 96.—Surface Ship Deployment Area

SOURCE: Office of Technology Assessment

couId be concern about the potential piracy of

the nuclear weapons loads.

Report-back could be accomplished through

high-orbit millimeter wave satellites. A 5-inch

dish antenna could be used to report back to

NCA on a regular basis. Since the beam from

the ship-borne antenna would be very narrow,

there would be a very low probability of transmissions being intercepted. The antenna wouId

normally be recessed within a section of the

ship so it could not be observed from other

ships, aircraft or high-resolution satelIite

photography.

The ships could constantly monitor their

position using the Global Positioning System

(GPS) anywhere in the deployment area. On a

command to launch, the missiles could be slid

into the water from ramps deployed to the rear

of the ship and fired from a floating capsule

container.

Since sliding missiles into the water would

be visible to a trailing observer, such a procedure would invite preemptive sinking of the

ship. An alternative method of launch would

be to carry the encapsulated missiles inside the

hull and launch them through the bottom of

the hull as the ship moves forward. The encapsulated missile would then rise to the surface

behind the advancing ship. Upon broaching

the surface of the water, its engines would be

ignited and it would fly out of the capsule. In

this manner, it would be possible to launch the

missiles without providing a trailer with tactical warning of a launch.

Another possible means of obtaining navigational fixes would be to use the acoustic

transponder fields that had been placed

throughout the deployment area. If the GPS

were attacked, these fields could be used when

the the Ship’s Inertial Navigation System

(SINS) has to be reset. Deployment to acoustic

transponder fields would take 11 to 12 hours,

well within the period of time needed between

updates (see ch. 5 for a more complete description of the SINS capabilities).
Ch. 7—Surface Ship Basing of MX ● 239

SOVIET DATA COLLECTING ACTIVITIES RELEVANT TO

THE VULNERABILITY OF MX-CARRYING SHIPS

The MX-carrying surface ship would carry 8

to 10 cannisterized MX missiles and would displace about 15,000 tons. The need to carry a

heavy load of cannisterized missiles, to maintain at-sea endurance, and to have a highspeed capability dictates the size class of the

ships.

Table 30 presents Department of Commerce

statistics on the number and displacement of

ships in the world. There are 5,094 ships with

displacements greater than 10,000 tons and

1,561 ships with displacements over 15,000

tons. There are 130 ships with displacements

over 15,000 tons that fIy American flags.

Figure 97 is a plot of the number of merchant

freighters in the world versus speed. As can be

seen from the plot, there are very few merchant ships in the world capable of being used

to trail an MX ship with a 30 + knot burst

speed. The bar graph in figure 98 shows the

number of merchant freighters as a function of

displacement. The graph shows that there are

1,400 to 1,500 merchant freighters in the world

with displacement greater than 15,000 tons

and about 1,400 merchant freighters with displacements between 13,000 and 15,000 tons.

Between 1,500 and 3,000 of the world’s 24,000

ships would be in a class that couId potentially

be mistaken for MX-carrying ships.

Figure 97.—Speeds of World’s Merchant Ships

2400 ‘ , .

2100

1800

1500

1200

900

600

300

0 5 10 15 20 25 30 35

Speed in knots

SOURCE: Department of Commerce

Figure 98.— Displacements of World’s

Merchant Ships

3000 

Q

C

2000

1000

1 2 3 4 5 6 7 8 9 10 11 1213 14 15

Displacement in thousands of tons

SOURCE: Department of Commerce

Table 30.—Number and Displacement of Ships in the World

World ships over 1,000 gross tons

Total number Passenger and Bulk

of ships cargo Freighters carriers Tankers

24,511 487 14,410 4,651 5,233

Merchant-type freighters over 1,000 gross tons

U.S. flag Government

World total Foreign flag total Private owned

5,094 4,657 437 177

Merchant-type freighters over 15,000 gross tons

U.S. flag Government

World total Foreign flag total Private owned

1,561 1,431 130 125 5

SOURCE: Department of Commerce.
240 ● MX Missile Basing

Any sensible Soviet reaction to the deployment of MX-carrying surface ships would involve the cataloging of surface ships of the

world. Such a catalog would include all free

world surface ships of length, width, and displacement similar to that of the MX surface

ships. The catalog would contain information

about all relevant measurable characteristics

that could aid in identification of the ships.

Such data would include the following list of

information:

● length, width, and draft of the ship;

● displacement;

● propulsion (steam, gas-turbine, diesel);

● side-view profiles;

. radar signatures at different frequencies;

. infrared signatures; and

● acoustic signatures.

Other ship features useful in “tagging” ships

would be such identifiable characteristics as

hull length-to-width ratios; hull shapes; wake

characteristics; and the positions of hatches,

booms, and lifeboats. Much of this data could

be obtained from standard sources on commercial shipping and the rest could be obtained by making measurements while ships

leave and enter commercial ports. Data could

also be collected by trawlers, surface combatants, satellites, submarines, and airplanes.

These data could be correlated with data collected by shore observers on the characteristics, numbers, departure times, and destinations of merchant ships in deepwater ports

around the world.

In the discussion that follows, it should be

kept in mind that this background of data collecting would be an ongoing process, constantly being refined and updated, so that radar, infrared, optical, and acoustic data would be

available for purposes of “sorting” ships.

THREATS TO MX SURFACE SHIPS

The threats to a surface ship fleet fall into

two broad categories:

1. continuous trailing of the MX ships so that

a coordinated attack could be executed at

will, and

2. wide area tracking of the surface fleet so

that MX ships could be localized well

enough to attack at will.

Continuous trailing would most likely be attempted by picking up the ships as they egress

from known operating ports. Ports from which

ballistic missile ships operate would have

special facilities for loading MX missiles onto

the ships. Since the missiles are very large and

there are strict explosive handling safety requirements, these facilities would be easily

identified by onshore agents or satelIite reconnaissance. Ships that are pulled up to these

docks could either be photographed by satellite or observed by onshore agents. These data

would be added to the Soviet computer catalog of ship characteristics.

Wide area, open ocean search could be attempted with aircraft, satellites, or over-thehorizon radar systems. Since the area in which

the ships would operate would be enormous,

search by aircraft would be very difficult and

expensive. Optimistically, a fleet of 600 to 800

long-range surveillance aircraft and 100 to 200

airborne refueling tankers would be required

to localize enough ships in a short enough time

to be able to destroy a large fraction of the

force. Other wide area search techniques that

would be more promising include infrared, optical, and radar search using satellite-borne

sensors and over-the-horizon radar search

using frequency scanning radars.

Continuous Trailing

A potential Soviet response to the deployment of a fleet of MX-carrying surface ships

could be to deploy a fleet of surface ships to

maintain and establish trail on MX ships

operating at sea. If a high percentage of MX
Ch. 7—Surface Ship Basing of MX . 241

ships could be brought under trail, a preemptive strike could result in the loss of a large

part of the MX fIeet.

Establishing and maintaining trail at sea is

not Iikely to be a simple matter. The success or

failure of such operations will depend on the

capabilities of the trailing ships, availability of

support forces to aid the MX ships, tactics, and

environmental conditions. There are also political and legal factors that could affect the activities and tactical options of both the trailing

and trailed ships. Such factors are difficult to

analyze in technical terms, since they basically

involve violations or reinterpretations of international law of the sea. Operations or tactics

that would require routine violations of international law are therefore not considered in

detail in the technical assessment to follow.

In order to trail a fleet of MX-carrying surface ships, the Soviets might build a new type

of surface ship with the necessary speed and

endurance to transit from home ports, trail the

MX ship for 60 days, and transit back home for

resupply and refit. The surface ships would be

equipped with surface search radars, infrared

and optical search systems, and facilities for

handling remotely piloted vehicles and/or

helicopters. They would also be equipped with

surface-to-surface cruise missiles, torpedoes,

and possibly cannon. Possible ports from

which the ships would operate might be Cuba,

or Murmansk, Petropavlosk, and Vladivostok.

Table 31 shows transit distances to ports that

might potentialIy handle the surface ships.

In order for Soviet ships to continuously trail

MX ships, one or more of these ships would

have to be available to trail ships as they

egressed from port. Figure 99 shows a possible

scheduIe for keeping track of MX-carrying surface ships. The middle horizontal time line

shows the total cycle for a Soviet ship-trailing

mission against MX-carrying surface ships. The

ship first transits to the port from which the

MX ship operates, waits outside the port until

the MX ship leaves on a sea patrol, trails the

MX ship for the sea-patrol period, transits back

home, and undergoes refit and resupply in its

home port. The top and bottom horizontal

time lines in figure 99 show the activities of

Table 31.–Operational Factors Affecting Fleet of

Soviet Trailing Vessels

Transit a Transitb Basec Requiredd

distance time loss number

(nmi) (days) factor of ships

Murmansk

to Norfolk . . . . . . . . . . . . 4,300 17.9 1.51 1.78

Murmansk

to Cuba . . . . . . . . . . . . . . 4,600 19.2 1.53 1.80

Cuba to

Norfolk ... , . . . . . . . . . . 870 3.6 1.23 1.45

Cuba to

Charleston . . . . . . . . . . . 610 2.5 1.20 1.41

Petropavlosk

to Seattle . . . . . . . . . . . . 3,600 15.0 1.46 1.72

Petropavlosk to

San Diego . . . . . . . . . . . . 2,800 11.7 1.40 1.65

a on e . way transit distance,

b Tw o .way transit time assuming 20-knot average transit speed.

cAssumes ships spend 5 days In ref!t and an average of 7 days on Port watch

waiting to pick up MX ships leaving port.

dAss umes that 15 percent of the tra!ling ships are In overhaul at all times.

SOURCE: Office of Technology Assessment

other trailing ships that are either transiting

from home base to take up position outside of

port or transiting to home bases after having

completed an at-sea trailing mission. The number of ships needed in order to keep one ship

constantly available for trailing at sea would

then be given by the expression:

B ,+ = 3 (total cycle time) – 2 (TOW + T,,J

(total cycle time)

where:

Blf = base loss factor

total cycle time = 2 T~,.n,lt + T~

,W + Tt,<,ll + T,e~lt

T pw – time — spent in port watch

Ttrail = time spent trailing surface ship

Ttran~lt = time spent in transit to or from home por t

‘reftt = time spent in port for refit

The base loss factor Blf is simply the number of

ships needed to keep a single ship on station at

all times. Additionally, this factor must be adjusted for the percentage of ships that would

be unavailable due to major overhaul activities in shipyards. The required number of ships

would therefore be given by the expression:

Total number of ships

required for tra i i ing = (number of MX ships) (B,(

)

(1 - FO

)

where:

F. = fraction of time ships in overhaul

Table 31 shows typical transit times to and

from different Soviet ports to ports from which
242 ● MX Missile

SOURCE: Office of Technology Assessment

MX missile ships might operate. The base loss

factors and number of ships necessary to continuously cover different ports are also presented. These factors were calculated assuming Soviet ships spend an average of 5 days in

port changing crews and being resupplied and

an average of 7 days on port watch waiting to

pick up a trailing ship. It would therefore be

necessary for the Soviets to build a fleet of 45

to 50 ships in order to have a ship continuously

available at sea to pick up and trail surface

ships as they leave port.

Initiating trail as the ship leaves port could

be a potentially complex operation. A line of

reconnaissance ships could be set up outside

the port using relatively slow and inexpensive

trawlers to patrol sectors of line. Onshore

observers could also be used to inform ships

on the line of departure of a surface ship. Surface search radars could be used to detect the

egressing surface ship and imaging radars

could be used as an aid to identification in fog.

At night, infrared sensors and TV cameras

could also be used. The ships on the reconnaissance line could also be equipped with remotely piloted helicopter vehicles and fixedwing remotely piloted vehicles. These aircraft

could be launched in good or bad weather to

help cover large areas of the ocean. They

would also be of use if multiple ships egressed

from port and it was necessary to obtain a

high-resolution look at several ships in order to

identify the MX-carrying ship. The number of

fast-trailing ships kept on station outside the

port would always be greater than or equal to

the number of MX ships in port at any one

time. Multiple egresses and surging of MX

ships would be possible to complicate portwatch operations but this would have to be

balanced against a requirement to keep missiles on station. If the missile ships were surged

too often, it would result in periods where the

United States would have more than the desired number of missiles on station and other

times when the United States would have less

than the desired number of missiles on station.

The number of ships required for the reconnaissance barrier can be estimated by considering the geometry of a port egress, number of

MX-carrying ships in port, the range at which

an MX ship can be detected, the barrier ship’s

ability to identify a ship as an MX carrier, and

the rate at which multiple ships could exit the

port. Figure 100 shows the geometry of a port

egress for a range of exit tracks. The length of

the barrier is:

barrier length = 2 L sin A

1 + cos A

where:

L is the territorialIit-nit
Ch. 7—Surface Ship Basing of MX ● 243

Figure 100.—Geometry of Barrier Outside a Port

With Unobstructed Access to the Sea

SOURCE: Office of Technology Assessment

Assuming that the territorial limit is 12 miles

and the ships can exit within a cone of 150

the barrier length would have to be about 45

miles long. This geometry could apply to ports

like San Diego, Charleston, Seattle, and San

Francisco. Ports like New York and Boston

have considerably more constricted access to

the sea and would therefore require shorter

barriers (see fig. 101). The average number of

merchant ships leaving three major American

ports are listed below:

Average number of

Port exits per day

Bosto n . , 10 to 20

New Yor k 60 to 80

San Francisc o 30 to 50

Two extreme cases are of interest: Ships exiting port at a uniform rate over a 24-hour

period and ships exiting port at a maximum

rate at one time. A maximum rate might be

estimated by assuming that the ships would

maintain 1,000 yd between them and exit at 10

knots. The maximum rate would therefore be

one ship every 3 minutes. If the exits occurred

during conditions of poor visibility, the ships

might instead maintain a 2,000- to 3,000-yd

distance and exit at 5 knots. This exit process

would make the maximum rate one ship every

12 to 18 minutes. If the displacements of the

exiting ships reflected that of the world’s

ocean going ships, 15 to 25 percent of the ships

would be 15,000 tons or over. Thus, assuming a

very busy commercial port could be used for

deployment of nuclear armed MX ships, an exit

rate as high as three to five ships an hour in the

15,000-ton class could be leaving port during

Figure 101 .—Geometry of Barrier Outside a Port

With Obstructed Access to the Sea

SOURCE Office of Technology Assessment

peak periods of shipping. These ships could

possibly be MX carriers and might have to be

inspected at close range by the barrier patrol

ships.

In actuality, it would probably not be

necessary to inspect all these ships closely,

since onshore observers could collect information on sailing schedules and send confirmation to the offshore ships on the sailing of the

ship. It would therefore be necessary only for

the barrier ships to leave their stations if it appeared that more ships of the right size were

crossing the barrier than expected.

Assuming that the barrier ships used surface

radars with a range of 5 miIes, five ships would

be required to maintain a constant barrier patrol. This total might be an adequate number

for average peak sailing periods. Since the barrier ships would more closely approximate

trawlers rather than the more expensive trailing ships, a prudent and determined adversary

might commit two or three times as many

ships.

If the port was not a major commercial port,

then peak exit rates could only occur if several
244 . MX Missile Basing

ballistic missile ships exited at the same time.

Since scheduling of trailing ships would be

responsive to such fluctuations, additional

long-range trailing vessels could be on station.

“Delousing” of Trailers at Port Egress

A number of options are available to ships

that are attempting to “delouse” themselves as

they egress from port. The problem with such

measures is that they may involve tactics that

may be uncharacteristic of merchant ships or

may result in serious delays before the patrol is

successfully begun. More serious yet, the tactics may be fruitless against ships equipped

with modern sensors. These tactics might inCI ude:

1. make repeated exit attempts until free,

2. use alternate port exits when available,

3. coast run to avoid the port watch barrier,

4. take advantage of dark and bad weather,

5. utilize military escorts to harass barrier

ships, and/or

6. jam barrier ship sensors.

Tactics 1 through 4 would be very difficult

to use successfully against ships equipped with

modern sensors. Tactic 5 could create a large

number of incidents that could have international repercussions. Tactic 6 would be very

difficult to do if the ships were equipped with

high-quality radars with good beam-forming

and anti jam signal processing.

The success or failure of trailing operations

would depend in a sensitive way on many details of ship operations, on the resolve of the

trailing and trailed ships, the quality of the

equipment available to each side, and on the

resourcefulness of the different ship commanders. If the adversary is determined to

commit the resources to establish trail, there

appears to be little hope that the MX ship

would “delouse” itself during egress from port.

Once at sea, there also appears to be little

opportunity for delousing. However, it could

be argued that bad weather or tactical

maneuvering could be used repetitively until

trail is broken. This possibility is explored in

the next section.

At Sea “Delousing” of Trailers

It is of interest to determine how large a

fraction of the force might be free of trail if it

is assumed that bad weather or some other opportunity to break trail presents itself to the

ships.

Low-visibility conditions at sea could be of

use in “delousing” the surface ships. The

percentage of maritime reports in which visibility is below 1 mile is about 5 percent.

If a low-visibility condition is assumed to exist for 1 day, then on the average, the probability of encountering such a weather condition during a patrol of length n days would be:

P = I – (probability of clear weather)

= 1 - (1 - 005) ”

or

P = 0,95 for a 60-day patrol (i. e., n = 60)

The probability of encountering low visibility

weather on the ith day of the patrol would

simply be:

PI = (probability of i-1 days of good weather)

x (probability of bad weather on the i!h day)

= (probability of one day’s good weather)’- I

X (probability of one days bad weather)

= (1 – 0,05) ’-1 x (0.05)

If the probability of breaking trail during

low visibility is pb, the expected number of

days free of trail for a patrol of n days will be:

Q (probability trail will be broken)

X (average number of days before bad weather is

encountered)

= P~ x (average number of days before bad weather

is encountered)

= P~ X ~ (n – i) PI

i =1

The fraction of the fleet under trail at any

given time would be:

[

number of days number of days

F = on patrol — free of trail 1

n - Q

[number of days on patrol]

=

N

For 60 days at sea (n = 60 in the above summation), the average number of days free of trail

would be about 12 days if the probability of
Ch. 7—Surface Ship Basing of MX . 245

breaking trail during a day of bad weather is

O.S. if the probability of breaking trail during a

bad day of weather is 0.25, then the average

number of days free of trail would be about 6.

Thus, for the case where there is a 0.5 probability of losing the trailer when the weather is

bad, the fraction of the fleet under trail will be:

F = 60 – 12 s () 80

60

or 80 percent of the fleet would be under trail.

For the case in which the chance of losing

the ship during a bad day of weather was 0.25,

the fraction of the fIeet under trail would be:

F = 60 – 6 = ()90

60

or 90 percent of the fIeet would be under trail.

If the ships could somehow choose weather

conditions so that it was five times more likely

that they would encounter weather with visibility of less than 1 mile, then the probability

of encountering such weather on any given

day would go from 0.05 to 0.25. If again it is

assumed that the ships would lose their trailer

with a probability of 0.5 on any day that such

weather is encountered, the mean number of

days free of trailers would rise to 28 and the

fraction of the force under constant trail

would be 50 percent. If the ships lost the trailer

every time bad weather was encountered, the

fraction of the force under constant trail

wouId be only 7 percent.

Reacquisition of Trailed MX Ships

The discussion above assumes that once the

MX ship has been lost to the trailing vessel it is

not reacquired during the remainder of its patrol period. If a search is immediately initiated

once the trailer has lost the MX ship, and

remotely piloted helicopters or remotely piloted winged vehicles are used, it is possible

that the MX ship could be reacquired. If the

remotely piloted vehicle could fly at 100 knots

and had a modest radar with a range of 5 nmi,

then the vehicle could search about 1,000

m i

2

/hr. If the MX ship were to make a 30 +

dash upon determining the trailer had lost contact (a questionable action if the visibility were

less than 1 mile and other ships were nearby),

then it is conceivable that the ship could generate a large enough area of uncertainty to

evade the drone vehicles. If the drone vehicle

was not launched for half an hour after the

trail was lost, the ship could be anywhere in a

circle of radius 15 nmi. The trailing ship would

be at the center of this circle of area 700 mi’

when the drone is launched. If the drone flies

in widening circles around the trailing ship it

wil I have searched the 700-m i 2 area within

about 45 minutes. By that time the surface ship

could be within an area of radius of 36 to 37

miles (an area of 4,300 mi’). The drone might

therefore not acquire the surface ship in time

if it is not launched quickly from the deck of

the ship. If, instead, the drone is launched

within 15 minutes after trail is lost, it could be

expected to reacquire the ship with a probability of 1.

Since the ability to reacquire the target ship

is sensitive to the capability of the drone (i. e.,

its radar might have a 10-mile range instead of

a 5-mile range) and to how quickly the crew responds to the loss of trail, it is of interest to ask

what percentage of ships would be kept under

trail if the ships had some success reacquiring

lost trails.

Figure 102 diagrams the possible events that

might occur during a period of bad weather.

The lower branch diagrams the situation in

which trail is maintained during the period of

poor visibility. The upper branch diagrams the

events that could occur after loss of trail.

After loss of trail one of two events can

follow: the ship reacquires the trail or it fails to

reacquire trail. The lowermost diagram shows

the result of a situation in which the probability of losing trail is very high (7s percent). If

trail could not be reacquired and the ships

were able to seek out poor weather 25 percent

of the time (i. e., five times more bad weather

than would randomly be encountered) then 30

percent of the fleet would be under trail. If instead there was a 50-percent chance the trail

could be reestablished, the percentage of the

force under trail would then be 37 percent.

Therefore, the fraction of ships under trail
246 ● MX Missile Basing

Figure 102.—Loss of Trail Probability Event Tree could change significantly if the trailing ships

had a modest ability to reacquire trail.

It should also be noted that if a ship is taking

advantage of bad weather to intermingle with

other ships (so as to make it difficult for a

radar operator to keep track of the MX-carrying ship) it is relatively easy to sort ships with

the aid of fixed wing or helicopter-like drones.

If the MX-carrying ship makes a dash at 30+

knots, its acoustic output would be enormous

and it could be heard for many miles by the

trailing ship. The ship could then send a drone

in the direction of the acoustic signal to determine whether this was in fact the MX ship running for freedom, or just a decoy ship acoustically enhanced to sound like a fast running

surface ship. In any case, the use of advanced

pilotless drones with advanced sensors would

make the reestablishment of a temporarily

broken trail quite likely.

Regions of Poor Visibility Weather

The shaded region in figure 103 shows areas

of the world that have poor visibility a high

percentage of the time. Due to proximity to

the Soviet Union, Soviet air and ocean surveillance could be expected to be quite good in

the northern regions near the Bering and Norwegian seas. Therefore, the regions of poor

Figure 103.—Regions Where Visibility is

Often Poor

SOURCE: Office of Technology Assessment SOURCE: Office of Technology Assessment
Ch. 7—Surface Ship Basing of MX . 247

visibility weather that could be used for attempting to break trail would be only the

several hundred thousand square miles of

ocean west of Greenland and north of Antarctica. These regions will have weather that

varies significantly with changes in season. It

could therefore be expected that if these

regions were used extensively, the fleet could

be seriously unmasked during periods of clear

weather. Another problem encountered in

these regions is ice. While it would normally

not be considered prudent to operate in poor

visibility weather without radar, it would be

suicidal to do so in waters populated by icebergs. The radar emissions of the trailed ship

could therefore be used as an aid for the trailing vessel during periods of poor visibility. The

emissions would not exclude the trailer from

also observing the trailed ship with its own advanced radars as well.

Final Comments on Trailing

It should be clear from the above discussion

that the survivability of a fleet of MX-carrying

ships could be sensitive to operational details,

capabilities of search radars and possibly

weather. Advanced sensors and remotely piloted vehicles would substantially enhance the

ability of a fleet of trailing ships to maintain

trail. If there is a 5-percent chance per day that

trail will be lost (either due to weather, at-sea

tactics or equipment failures) as much as 45 to

50 percent of the fleet could be free of trailers.

This circumstance, however, would be very unlikely with the variety, diversity and reliability

of advanced sensing technologies that can be

expected to exist in the late 1980’s and early

1 990’s.

OTHER SURVEILLANCE TECHNOLOGIES

Although trailing would be the most technologically conservative means of keeping track

of the MX-carrying surface ships, there are a

number of other important technologies that

could either supersede the trail ing threat or be

used to aid the trailing vessels. These technologies are over-the-horizon radars and satelliteborne sensors.

Over-the-Horizon Radars

signal off the ionosphere (see fig. 104). The reflected signal from the target also bounces off

the ionosphere before it arrives back at the

radar receiver.

Over-the-horizon radars are restricted to frequencies no higher than that in the HF band

since higher frequencies are not substantially

reflected from the ionosphere. A consequence

of such a low radar frequency is that the radar

has low resolution.

An over-the-horizon radar illuminates tar- Figure 105 shows the scattered intensity at

gets over the horizon by bouncing a radar different frequencies for two similar looking

Figure 104.—Geometry of Over-the-Horizon Radar
248 ● MX Missile Basing

Intensity

Figure 105.— Radar Cross Sections of

Two Similar Looking Ships at Different

Over”the”Horizon Radar Frequencies

Partial ramp response

Shimokaze

Hayanami

Intensity A

— B o w

 Ster n

Partial ramp response

Frequency

SOURCE: E. K. Young and J. D. Walton, Surface Ship Target Classification

Using H. F. Radar, Office of Naval Research, Final Report 712352,

May 1980.

ships as they might appear to an over-thehorizon radar reflecting off a perfectly smooth

undisturbed ionosphere. Although the ships

are not resolved in a visual sense, the frequency dependent radar signal differs for each

ship. An actual over-the-horizon radar would

have to track ships in the presence of traveling

ionospheric disturbances and sea clutter.

It is possible that over-the-horizon radars

would be able to track and identify ships on

the surface of the ocean almost continuously.

This identification could be possible if the intensity of reflected radiation at different frequencies, can be measured accurately in the

presence of ionospheric disturbances and sea

clutter.

If this promising technology is successfully

developed, the range of observation is likely to

be on the order of 2,000 miles. An over-thehorizon radar would be unlikely to threaten

the fleet of MX-carrying ships but could be

used to open large areas of ocean to observation from shore-based radars.

Satellite-Borne Sensors

Satellite-borne sensors could include microwave radiometers (to pick up electromagnetic

emissions from ships), infrared sensors, optical

sensors, and various types of radars. Figure 106

shows the ground tracks of the Cosmos 749 satellite that has an orbital period of about 95

minutes and an orbit inclined at 740 from the

Equator. As the Earth rotates to the east, the

ground track of the satellite precesses to the

west. Because of the chosen orbital period, the

satellite ground tracks repeat themselves every

24 hours (or every 16 orbits).

Figure 107 shows the ground swath of the

satellite assuming that it has a sensor range of

500 to 600 miles from its ground track. The

changing shape of the ground swath is due to

the ground swath being drawn on a Mercator

project ion, with a changing distance scale.

Figure 108 shows the orbits for which it overflies the Atlantic. This overflight occurs twice

during a 24-hour period of 16 orbits. Figure 109

shows ground swaths of two successive satellite orbits. If the satellite sensors have a range

of 800 to 900 miles the satelIite swaths would

overlap even at the Equator and al I the overFigure 106. —Ground Track of Surveillance Satellite

in a 24-Hour Period

SOURCE: Stockholm International Peace Research Institute Yearbook
Ch. 7—Surface Ship Basing of MX ● 249

Figure 107.—Obsemation Swath of

Surveillance Satellite

SOURCE: Off Ice of Technology Assessment

Figure 108.—Single Satellite Repeat Coverage of

Mid-North Atlantic in a 24-Hour Period

SOURCE Off Ice of Technology Assessment

flown regions of the Earth’s surface could be

covered by a single satellite. If three such

satellites were launched in orbits separated by

an order of 700 to 800, the surface of the

Atlantic would be observed on an average of

every 3 to 4 hours (see fig. 110 for details of the

satellite overflight schedule). If the range of

the sensors did not allow for overlapping observations on successive orbits, more satellites

would be needed. A sensor range of 450 nmi

Figure 109.— Precession of Observation Swath on

Two Successive Orbits of a Surveillance Satellite

SOURCE: Office of Technology Assessment

would require 6 satellites and a sensor range of

225 miles would require 12 satellites. This

range would allow the Soviets to observe all

areas of the world’s oceans (with the exception

of the region near the North and South Pole)

every 3 to 4 hours.

If an extensive system of satellites was used

to observe (but not identify) large surface ships

while at sea, an operational need might arise

for the MX ships to make false reports to shore

using standard merchant HF channels. Since

owners of merchant ships usually want to remain informed about whether or not their ship

is on schedule, merchant ships will usually

report their positions to shore based H F stations once a day. If Soviet ships on regular

patrol routinely recorded HF messages and reported them back to a central facility, there

would be a very high probability that HF messages would be intercepted. These data could

then be combined with data collected from

published merchant ship sailing schedules and

satellite reconnaissance data to help identify

ships that might be MX carriers.

Satellites could not only be of use in observing ships on the surface of the ocean but signature data could be accumulated and correlated with observations from surface ships and

aircraft. If some form of “fingerprinting” could

be accomplished using either radar, infrared,

83-477 0 - 81 - 17
250 ● MX Missile Basing

Figure 110.-Search Schedule of Surveillance Satellites at Mid= Northern Latitudes

Satellite 1

Satellite 2 i

Satellite 3

Satellite 1

Satellite 2 — ---Search -

4 7 8 9 1011.11

‘1 . Search

 6 7

Satellite 3 Search Search Search

—.0 - --- -

Single coverage Double coverage Triple coverage

SOURCE: Office of Technology Assessment

or passive microwave sensors the ships could

be continuously tracked from space. “fingerprinting” was not technically possible, the

satellites could be used by trailing ships to

help reestablish contact with recently lost sur6 7

search

- -- —

face ships. This use of the satellites would

greatly reduce the need to trail at very close

distances and would also be an aid to picking

up ships after port egress.

MX REQUIREMENTS AND SURFACE SHIP FLEET

As has been demonstrated in the sections

above, major uncertainties would exist with

regard to the survivability of a fleet of MXcarrying surface ships. These uncertainties

derive from the fact that surface ships are

observable at very great distances. As sensing

technologies advance, new and novel capabilities for detecting and “fingerprinting” surface

ships at great distances can be expected to

contribute to surveillance capabilities. Once

“fin gerprinted,” a surface ship would not have

to be resolved in the sense that is usually associated with “seeing” an object, if it is to be successfully tracked. While it can be expected
Ch. 7—Surface Ship Basing of MX ● 251

that tracking capabilities would change with

the weather, time of day, and ship operations,

it cannot be expected that cover of night or

bad weather will dramatically enhance the survivability of such a fIeet.

Another aspect affecting the survivability of

a fleet of MX-carrying surface ships is the

operational circumstances of individual ships.

These circumstances would be constantly

changing with time. The survivability of some

ships may be due to circumstances independent of those of other ships (i. e., some ships may

have to transit between bad weather while

other ships do not) or may be due to circumstances dependent on those of other ships (a

trailer confronted with two ships, might, for instance, have to choose which ship to trail). The

survivability of such a fleet of surface ships is

therefore an unpredictably changing variable.

Since the surface ship fleet would have to be

sized to allow for ships destroyed in preemptive action, and the survivability is a constantly changing unpredictable variable, there

is no way to size the fleet for such a contingency. It is therefore important to note that it

is unlikely that the requirement for 100 surviving rnissi/es on station after any enemy action

can be met on a continuous basis if MX were

deployed on surface ships.

ACCURACY OF SURFACE-SHIP-BASED MX

The guidance technology used by surfaceship-based MX would be largely the same as

that used for submarines. The accuracy figures

discussed below assume the same sets of

guidance technologies as those discussed in

the chapter on submarines.

Since surface ship survivability requires that

the ships operate in as large an area of ocean

as possible, many of the ships could be expected to be at a full 6,000-mile range from

Soviet targets.

Figure 85 in chapter 5 shows the CEP multiplier v. range for an inertially guided missile

and a star-tracker-aided inertially guided

missile. The CE P multiplier is a number defined

as the CE P of the sea-based missile divided by

the CEP design requirements of the land-based

MX. Thus, an accuracy multiplier of 1.5 means

that the CEP of the missile in question is 1.5

times that of the CEP design requirements of

the land-based MX.

As noted in chapter 5, it is expected that the

land-based MX will exceed its CEP design requirements, so a CEP multiplier of 1.0 does not

necessarily mean accuracy equal to a landbased MX.

Figure 85 is a plot of CEP multiplier at a full

6,000-nmi range for a sea-based MX guided

with purely inertial technology and with inertial technology aided by a star tracker. For

pure inertial guidance, at a range of 6,000 nmi

the accuracy of the missile would be degraded

relative to the accuracy design requirements

of the land-based MX. If the advanced inertial

measuring unit were aided with a star tracker,

the CEP multiplier at 6,000 nmi could be expected to be comparable to the design requirements set for the land-based missile.

If the surface ship fleet were forced to

deploy at 6,000-nmi ranges from Soviet targets

and the sea-based MX has purely inertia I

guidance the single-shot kill probability

against hard targets would be degraded.

However, if the hard targets were to be attacked with two warheads, the double-shot kill

probability would still be high.

If a star tracker were added to the inertial

guidance system of a sea-based MX, the accuracy would degrade much more slowly with

range. I n this case, ships deployed at a 6,000-

nmi range from targets could have CEPs comparable to the design requirements set for the

land-based MX. For this set of circumstances

the single-shot kill probabilities would be very

large and, correspondingly, the double-shot

kill probability would also be very large.
252 ● MX Missile Basing

A third system of guidance technologies that

might be used would be to enhance the accuracy of the missile by updating the inertial

guidance system of the missile with the aid of

a system of radio ground beacons or with the

GPS. Using this system of guidance, MX accuracy would be achieved against Soviet targets from any point in the deployment area if

the GPS were used.

If the GPS was unavailable due to attacks on

the satellites, the ground beacons deployed on

the coast of the continental United States and

the coast of Alaska could be used instead. In

order to use the ground beacons, it would be

necessary for the ships to deploy to areas

within which the missiles could “see” the

beacons after launch. These regions are shown

in figures 86 and 87 in chapter 5.

RESPONSIVENESS OF A SURFACE SHIP FORCE

The operational complexity of a surface ship

force could make it very difficult for a fleet of

MX-carrying surface ships to be responsive to

NCA.

A major operational problem that could affect the responsiveness of the force is the low

survivability of the ships to preemptive action.

It would be necessary for a roll call to be taken

in order to be sure that high-priority targets

were covered. If ships were still threatened

with attack during the process of taking the

rolI call, high- priority targets would have to be

reassigned to stilI other surviving ships. This reassignment could make the timing of a large

coordinated strike extremely difficult to

execute.

It is also possible that hostile forces would

be unable to attack the remaining ships. This

inability could occur if the United States successfully destroyed Soviet surveillance sensors

and a significant portion of Soviet Naval

forces. Under these conditions, retargetting

the ships could be done with a multisynchronous satellite system, that would have the

ability to survive Soviet antisatellite attacks.

Since the satellites would use extremely high

frequency (EHF) channels, the ships could

direct transmissions into such a narrow beam

that the probability that the ships’ transmissions would be intercepted would be very low.

The ships could then communicate two ways

with NCA at very high data rates and retarget

the surviving MX missiles.

A surface ship would have the ability to

maintain high accuracy for an indefinite

period of time after antisatellite attacks on

GPS if the missile guidance system were based

on star tracker enhanced inertial guidance and

the ships inertial navigation system utilized advanced guidance technologies. Under these

conditions the ship could carry out launch

orders against very hard targets without serious delays.

If the missile guidance were purely inertial,

missile accuracy wouId rapidly be degraded as

a function of time (in a period of time of tens

of hours rather than tens of days). This degradation occurs because the star tracker can be

used to help correct for navigational errors

which accumulate over time in the ships’ navigational system. If the missile does not have a

star tracker, errors in the ships navigational

system cannot be compensated for during the

early portion of the missile’s flight.

Without a star tracker update, the damage

expectancies against very hard targets would

be significantly degraded over time unless the

ships positioned themselves near acoustic

transponder fields so they could update their

guidance systems. The ships would then have

to operate in a manner that could diminish

their survivability.

If the missile guidance were based on radio

beacon updates of the missile’s guidance system, the ships would have to redeploy to the

areas shown in figures 86 and 87 in chapter 5.

In this case, redeployment activities could

delay execution of the force for days and the

responsiveness of the system would be poor.
Ch. 7—Surface Ship Basing of MX ● 253

FLEXIBILITY

If attrition of the force was occurring on a

time scale on the order of that required for attacks on targets, flexibility of targeting would

be nonexistent.

If the force was not being attritted and there

was confidence that ships ordered to carry out

attacks would survive long enough to carry out

orders, targeting flexibiIity of the MX-carrying

surface ships would be possible. This flexibility

wouId be accomplished using communications

channels through the multi synchronous EHF

satellites or simply with VLF transmissions

from land-based VLF stations or survivable airborne VLF radio relays. Emergency Action

Messages could be transmitted over VLF if preplanned options or sub-options within preplanned options are to be executed. Large

amounts of data required for ad hoc attacks

on targets designated by latitude, longitude,

and height of burst would be transmitted over

the EHF channels through the multisynchronous satelIites.

ENDURANCE

The endurance of a fleet of surface ships would have to return to port for at least s o

could be very great provided the ships were days. At the end of 90 days, half of the survivnot under constant attack from sea-based ing ships would have to return to port and by

Soviet assets. The ships could have an at-sea the end of 120 days surviving ships would

endurance in excess of 120 days. Assuming either have to be replenished at sea or return

that the ships were at sea for an average of 30 to port.

days at the beginning of hostilities, no ships

COST AND SCHEDULE

The surface ship considered for the cost

analysis is the SL-7 type fast containership . The

specifications of the SL-7 are shown in table

32, It should be noted that this ship was chosen

for purposes of costing because it is an existing

design of a merchant ship with a very high

speed (33 knots). It is unlikely that SL-7S would

be a good choice of surface ship because the

ratio of its hull length to width would be easily

distinguishable from space. It should be noted

that the SL-7 has insufficient fuel capacity to

stay at sea for more than 26 to 27 days at a 20-

knot patrol speed. The ship could be operated

at a lower average patrol speed but this would

make the endurance requirements on Soviet

trailers less severe and would therefore

diminish the stress on Soviet forces committed

to tracking the ships, Therefore, at a minimum,

the ships would have to be modified to carry

an additional 5,000 to 6,000 tons of fuel or

wouId have to be refueled at sea.

The Iifecycle cost estimate for a fleet of

SL-7-type surface ships is presented in table 33.

Initial operational capability would be

sometime in 1987, assuming the success-oriented missile development effort is not seriously delayed by the need for guidance system

modifications or redesign. This date is determined by the long Ieadtime needed for the MX

missile, not by long Ieadtime required for the

construction of ships. The time estimated for

construction of the leadship is on the order of

3 years. The time required for follow-on ships

would be on the order of 2 years.

If it turned out to be feasible to home base

the ships near the Atlantic strategic weapons

facility (SWFLANT) and the Pacific strategic

weapons facility (SW FPAC), some costs and

construction could be avoided,
254 ● MX Missile Basing

Table 32.—SL-7 Specifications

Length overall

Beam

Draft - design

operating

Propulsion

Shafts

Boilers

Shaft horsepower (total)

Depth at main deck

(fwd of aft deck house)

Depth at main deck

(aft deck house to fantail)

Speed (light draft)

Displacement - 30’ draft

34’ draft

Fuel capacity

Fuel consumption -33 kts

25 kts

19 kts

12 kts

Electrical capacity

946’ 1-1/2”

105’ 6“

30’

34’

Geared steam turbines

2

2

120,000

64’

68’ 6“

33 + kts

43,000 tons

50,300 tons

4,434 tons

614 tons/day

240 tons/day

159 tons/day

34 tons/day

2 installed, 3,000 kW

Ships service turbo

generator

1 installed 1,500 kW

Ships service diesel

generator

1 installed, 60 kW

Emergency diesel

generator

SOURCE J W Noah

It is also possible that ships could operate

from other existing naval bases. The feasibility

of this approach would be determined by the

availability of waterfront area and land near

these bases. There would be a need to construct additional waterfront facilities for the

ships. These facilities would have to be constructed to satisfy “minimum” safe handling

distances for explosive materials. Large

amounts of additional real estate would also

be required for a missile assembly area and a

weapon storage area.

It should be noted that early deployment

(i.e., 1987) of a few MX-carrying surface ships

would not necessarily result in surviving missiles at sea, as would be the case with submarines. Because surface ships achieve survivability by dispersing in large areas of the

Table 33.—1 O-Year Lifecycle Cost

(billions, fiscal year 1980 constant $)

Cost element Number cost

RDT&E

Surface ship — $0.100

Missile — 6.056

SWS — 0.400

Capsule — 0.282

Nav. aids — 0.190

Total RDT&E $7.028

Procurement

Surface ship 30 $9.983

Basing 2 4.830

Missile 485 5.578

SWS 2.190

Capsule 5% 1.705

Nav. aids 1 500/3000 1.400

Total procurement $25.686

Total acquisition $32.714

Operating & support

IOC to FOC $ 1.165’

FOC + 10 8.879

Total operating & support $10.044

Total 10-year LCC $42.758

“Note: Ship availability and basing availability are not compatible, therefore

interim support ship basing used.

SOURCE Office of Technology Assessment

ocean in an attempt to exhaust Soviet trailing

and monitoring capabilities, the first surface

ship that goes to sea may face substantial

Soviet trailing assets. The survivability of a

fleet of surface ships will depend on the ability

to spread trailing forces thin enough that it is

difficult for a trailer to reacquire the ship if it

is lost. A Soviet decision to commit substantial

assets to trailing a fleet of surface ships could

result in a substantial Soviet trailing capability

by the time the first lead ship is deployed. The

survivability of the surface ships would only

improve as more ships came on Iine, taxing the

capacity of the Soviet trailing fleet and driving

the size of the Soviet trailing commitment to

substantial levels.
Chapter 8

LAND MOB LE MX BASING
Chapter 8.— LAND MOBILE MX BASING

Page

Barrage Attack on Mobile Systems . . . . . . . . . . . . . . . . . . . . . ..........258

The’’Area Kill’’Mechanism . . . . . . . . . . . . . . . . . . . . . . . . . . . .. ....258

Attack On Mobile Basing Systems . . . . . . . . . . . . . . . . .........260

Land Mobile MX Mx BasingConcepts . . . . . . . . . . . . . . . . . . .. ...261

RoadMobileMX: Continuously Dispersed . . . . . . . . . . . . . . . 261

Road MobileMX: Disperse-on-Warning . . . . . . . . . ., 263

Off-RoadMobileMX . . . . . . . . . . . . . . . . . . . . . 264

Dash-to-Shelters. 2 6 4

Rail MobileMX .. .....’” . . . . . . . . . . . . . . . ’..26 4

FIGURE S

Page

111, Lethal Radius of One-Megaton Weaponas Function of Vehicle

Hardness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258

112. Lethal Radius as a Function of Weapon Yield for Various Values of Vehicle

Hardness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259

113, Barrage Patterns of One 8-M-l_ Weapon and Seven 430-kT Weapons 259

114. Area Barraged byan ICBM Force of 3,000 EMT as a Function of Vehicle

Hardness . . . . . . . . . . . . . . . . . . . . . . . . . . 260

115 Length Barraged by an ICBM Force of 3,000 e-Megaton Reentry

Vehicles as a Function of Vehicle Hardness. 260
Chapter 8

LAND MOBILE MX BASING

Land mobile MX-basing systems would seek

to create uncertainty for the Soviet targeter by

constantly changing missile location in an unpredictable way. If the locations of the missilecarrying vehicles were completely unknown to

the Soviets, then the only way to attack them

would be to barrage or pattern bomb the deployment area, spreading destructive effects

over as wide an area as possible. To guarantee

survival of a fraction of a land mobile force,

the deployment area would have to be larger

than the area that the Soviets could “sweep

clean” with a barrage. If the Soviets were able

to observe the vehicles by remote means and

target their attack at individual vehicles on the

basis of recent sightings, then the vehicles

would have to be fast enough to generate a

large uncertainty in their locations in the time

elapsed between the last preattack sighting

and the arrival of RVS targeted on the basis of

that last sighting.

In either case, the Soviets would have to

blanket as much area as possible with nuclear

effects lethal to the MX-carrying vehicles. The

“area kill” mechanism — as opposed to the

aimpoint or hard-target kill relevant for missile

silos or multiple protective shelters (MPS)—

has the important feature of being insensitive

to Soviet fractionation. Roughly speaking, the

area (or length of road or rail) the Soviets could

barrage with nuclear destruction of a given

severity wouId depend on the number and size

of Soviet missiles but not on whether the missiles carried a small number of high-yield reentry vehicles (RVS) or a larger number of smaller

yield RVS. The small warheads would be more

numerous, but each would barrage a smaller

area, and the total area covered by all the warheads from a given missile would be roughly

the same no matter what the fractionation.

Said another way, the vulnerability of a land

mobile MX basing system would be sensitive to

the total throwweight in the Soviet arsenal but

not to how that throwweight was apportioned

among RVS.

Because it would be more difficult for the

Soviets to increase their throwweight than

their number of RVS, the “area kill” vulnerability of Land Mobile systems is attractive in principle. However, it is difficuIt to realize in practice.

Road mobile MX could either have missilecarrying trucks continuously in motion on the

highways (Continuously Dispersed Road Mobile) or stationed at central bases and dispersed onto the highways on warning of Soviet

attack (Disperse-on-Warning Road Mobile).

Off-Road Mobile could either have hardened

vehicles moving randomly throughout a large

area or dashing from central bases to dispersed

hardened shelters. Rail Mobile MX would

travel the Nation’s raiIways.

None of the land mobile concepts turns out

to be a particularly attractive option for MXmissile basing, but Continuously Dispersed

Road Mobile could be highly survivable, and

its survivability would be independent of warning. Disperse-on-Warning systems would require hours of warning time if they were to survive attack, so they would always be vulnerable to surprise. Off-Road Mobile would require a very large deployment area. Dash-toShelters would use a smaller amount of land

than Off-Road Mobile but would still depend

on warning. I n fact, MPS basing with preservation of location uncertainty (PLU) could be

viewed as an evolution of Dash-to-Shelters

with dash reemphasized to achieve independence from warning. Rail Mobile would suffer

from the need for right-of-way on intercity

lines.

In addition to problems with the fundamental concepts, land vehicles capable of carrying

the 190,000-lb MX missile would be very large.

A road vehicle would probably be much too

large to fit under highway underpasses and too

heavy to cross highway bridges. Thus, Road

Mobile MX is probably a practical impossibility. Off-road vehicles of MX size could be very

destructive of their deployment areas.

257
258 ● MX Missile Basing

BARRAGE ATTACK ON MOBILE SYSTEMS

This section discusses some basic features of

nuclear barrage attacks, the type of attacks

relevant to basing systems consisting of mobile

missile-carrying vehicles. In contrast to the survivability of systems of fixed hard aimpoints

like silos and MPS, which depends on the number, yield, and accuracy of Soviet RVS, the survivability of mobile systems depends on the

total equivalent megatonnage (EMT) in the

Soviet missile force. EMT in turn depends on

the size and number of Soviet offensive missiles but is insensitive to whether a given

missile carries a small number of high-yield

warheads or a larger number of smaller yield

warheads. That is, the Soviets would obtain Iittle advantage by fractionating their ICBM missiles with large numbers of multiple independently targeted RVS if the United States

were to deploy a mobile basing system. RV accuracy would also be irrelevant, since for soft

targets it would be sufficient for an RV to

detonate a few miles away (rather than a fraction of a mile, as with silos and MPS) in order

to destroy the missile-carrying vehicle. Since

mobile basing would deprive the Soviets of

any substantial advantage from modernizing

their ICBM force, the concept is very appealing. Unfortunately, it is difficult to translate

this hypothetical concept into a survivable

basing system, principally because the Soviets

already possess sufficient EMT in their ICBM

arsenal to destroy mobile vehicles dispersed

over even very large areas of the United States.

The “Area Kill” Mechanism

The distance from a nuclear detonation at

which a mobile vehicle could survive depends

on the vehicle’s “hardness,” or resilience to

nuclear effects, and on the weapon yield.

Hardness is typically quoted in pounds per

square inch (psi) of static overpressure. This

convention does not necessarily imply that

static overpressure is actually the effect that

destroys the vehicle or renders it inoperable:

gusting winds that follow the shock front (“dy -

namic overpressures”), thermal radiation, or

other effects might be responsible for vehicle

impairment. Rather, stating that a vehicle has

a hardness of so many pounds per square inch

means that it can survive the effects of a

weapon at distances from the detonation at

which the shock front applies that many psi

overpressure. Within the range at which the

given overpressure occurs, the vehicle is assumed destroyed; beyond that range, it is

assumed to survive. (In practice there is no

distance beyond which all vehicles would survive with 100-percent certainty. Instead, there

is a “sure-safe” distance, a “sure-k i I l“ distance,

and a certain probability of kill at distances

between. Also, if overpressure is not the kill

mechanism, the “hardness” will actually be a

function of yield.)

Figure 111 shows the range to which a given

overpressure extends as a function of overpressure for a l-MT weapon (ground ranges

from ground zero for optimum burst height).

This is the same as a plot of the “lethal radius”

for a vehicle v. the vehicle’s hardness. For instance, a 5-psi hard vehicle would be destroyed

at a range of 4 miles or closer, an 8-psi vehicle

at a range of 3 miles or closer, and so on.

Figure 11 l.— Lethal Radius of One-Megaton Weapon

as a Function of Vehicle Hardness -

0 2 4 6 8 10 12 14 16 18 20

Target hardness in psi

SOURCE: Office of Technology Assessment.
Ch. 8—Land Mobile MX Basing ● 259

For intermediate overpressures, the laws of

hydrodynamics prescribe a rough scaling law

saying that, for a given hardness, the lethal

radius increases as the one-third power of the

yield. Figure 112 shows lethal radius as a function of yield for various values of hardness.

if a vehicle is within a circle of radius equal

to its lethal radius, it will be destroyed. The

area of this circIe is “pi” (3.14) times the square

of the lethal radius. Since the lethal radius

varies as the one-third power of the yield, the

lethal area varies as the two-thirds power of

the yield. Since the area that can be “barraged” with a given overpressure is proportional to (yield)zls, the area that can be barraged by a given force of nuclear weapons is

proportional to the number of weapons times

the two-thirds power of their yield. This quantity is called the EMT of the force:

Barrage area proportional to EMT =

(number of weapons) X (yield)l )

where the yield is measured in megatons. Thus,

a force of 4,000 1-MT RVS has 4,000 EMT, and

a force of 1,000 8-MT RVS also has 4,000 EMT.

Since mobile basing systems seek survivability by dispersing over wide areas, their surFigure 112.—Lethal Radius as a Function of Weapon

Yield for Various Values of Vehicle Hardness

O 1 2 3 4 5 6 7 8 9 10

Yield in megatons

vivability depends on how much of the deployment area can be barraged by the Soviets,

which in turn depends on the total EMT in the

Soviet ICBM force.

It so happens that the EMT that can be delivered by a given ICBM depends (speaking

roughly) only on its throwweight and not on

how this throwweight is apportioned among

RVS. The effectiveness of a given missile in

barraging an area is relatively insensitive to

payload fractionation. The missile can carry a

small number of high-yield RVS or a larger

number of smaller yield RVS. The smaller RVS

would be more numerous, but each would barrage a smaller area. The total barrage area

would be about the same no matter what the

fractionation.

Figure 113 shows the barrage patterns of a

single 8-MT RV (4 EMT) and of seven 430-kil -

Figure 113. —Barrage Patterns of One 8-MT Weapon

(4 EMT) and Seven 430.kT Weapons (also 4 EMT)

8 MT 0.43 MT

5 psi contour = 8.7 miles — 5 psi contour = 3.3 miles

One 8-MT weapon = 4 EMT

Seven 0.43-MT weapons = 4 EMT

The area covered is about the same no matter how the EMT

is apportioned among reentry vehicles

SOURCE Off Ice of Technology Assessment SOURCE. Office of Technology Assessment
260 ● MX Missile Basing

oton RVS (also 4 EMT). The circles show the

areas within which a 5-psi vehicle would be destroyed. The barrage area is~bout the same no

matter what the “fractionation. ”

In summary: In contrast to a system of hard

point targets (silos or MPS), the survivability of

a mobile system which the Soviets had to barrage would depend on the EMT of the Soviet

missile force but would be relatively insensitive to the fractionation of each missile.

Therefore, to substantially increase the threat

to a U.S. basing system subject to area barrage,

the Soviets would have to build more missiles.

To increase the threat to silos or MPS, they

would need only to increase the number of

RVS carried by existing missiles. Furthermore,

since the lethal radius is a few miles for the

overpressures relevant to mobile basing, differences in RV accuracy of a fraction of a mile

are irrelevant to the area kill mechanism. Thus,

for purposes of attack on a mobile basing system, Soviet accuracy improvements would

gain them little.

Because their survivability would be insensitive to fractionation and accuracy, mobile

basing systems are attractive in principle.

However, the area the present Soviet ICBM

force can barrage is already quite large. Figure

114 shows the area that can be barraged by a

force of 3,000 EMT as a function of hardness.

The figure shows that such an arsenal could

destroy every 4-psi vehicle in an area the size

of Texas and every 7-psi vehicle in an area the

size of Nevada. It is clear that survivable

mobile MX-basing systems would require large

deployment areas.

Figure 115 shows the length of road or rail

that could be barraged by 3,000 l-MT RVS. Barrage length, unlike barrage area, is not proportional to EMT, but the outcome of a barrage

attack on a road or rail mobile basing system

would also be relatively insensitive to fractionation. Such an arsenal could also destroy

al vehicles on long stretches of road or rail.

Attack On Mobile Basing Systems

The outcome of an attack on a mobile basing system would depend on whether the SoviFigure 114.—Area Barraged by an ICBM Force of

3,000 EMT as a Function of Vehicle Hardness

600

t ~

Alaska (600)

M

C

r [

3,000 equivalent

360 , ; ~ meaatons assumed

320 .

2 8 0

240 ~ “ = s

. ,

2 0 0

160

1 -n : ‘

–=

‘Texas (270)

““~ ,. - ~“”v’da(”o )

024 6 8 10 12 14 16 18 20

Hardness of targets in psi

SOURCE Office of Technology Assessment.

Figure 115.—Length Barraged by an ICBM Force of

3,000 One-Megaton Reentry Vehicles as

a Function of Vehicle Hardness

100

70

* 60 -

a) 3,000 1-megaton

c = reentry vehicles assumed

-DE

g % 50 -

Interstate highway

waterways (35)

O 2 4 6 8 10 12 14 16 18 20

Hardness of targets

SOURCE: Office of Technology Assessment.
Ch. 8—Land Mobile MX Basing ● 261

ets knew where the individual vehicles were at

the time of attack in addition to depending on

the total EMT in the Soviet arsenal.

If the Soviets did not or could not track individual vehicles as they moved about the deployment area, they would have to barrage as

large a fraction of the deployment area as

possible. If the deployment area were twice as

large as the area the Soviets could barrage,

half of the MX force would survive; if the deployment area were three times as large as the

barrage area, two-thirds of the force would survive; and so on.

If the vehicles were stationed at fixed bases

and dispersed only when attack was imminent,

the Soviets would only have to barrage the vicinity of the bases. For instance, if the vehicles

dispersed in all directions when warned of

Soviet ICBM launch, and if the vehicles were

capable of speeds of 50 mph, then in the halfhour flight time of Soviet ICBMS they would be

dispersed within a circle of radius 25 miles

from the base. Since this circle would have an

area of only 2,000 mi 2, it would be easily barraged. Therefore, because of the slow speeds

of land vehicles, Disperse-on-Warning Road

Mobile systems would be vulnerable to surprise attack.

Even a continuously dispersed system could

be vulnerable if the Soviets were able to track

the vehicles continuously and retarget their

missiIes on the basis of up-to-the-minute information. Then they would only have to barrage the vicinity of each vehicle, not the whole

deployment area. The time it took the Soviets

to determine the location of each vehicle,

transmit the locations to their missile fields,

program their missiles, and launch them, plus

the half-hour ICBM flight time, is called the

“intelligence cycle time” (l CT). ICT is thus the

time from last sighting to attack arrival. The

important quantity in this case is the distance

the vehicles could move during the ICT. For instance, if a hypothetical Soviet surveillance

system and ICBM force were capable of a 2-

hour ICT (and this example by no means intends to suggest that such an ICT is feasible for

the present Soviet force), then the vehicles

would have two hours to move away from the

point where they were at the time they were

last sighted (this time would be chosen by the

attacker and would be unknown to the U.S.

force). If the vehicles patrolled in such a way

that they constantly changed direction, moving away from their starting point with average

speed of 40 mph, then when the Soviet attack

arrived they could be anywhere within a circle

of radius 80 miles. This circle would have an

area of 20,000 m i 2.

If the Soviet surveillance system were such

that it could not locate the vehicles precisely,

but only localize them within a circle of radius

20 miles, then a 2-hour ICT and 40 mph average speed would result in a “circle of uncertainty” of radius 100 miles and area 31,000 mi2

.

LAND MOBILE MX BASING CONCEPTS

Road Mobile MX:

Continuously Dispersed

A system of missile-carrying road vehicles in

continuous motion on the Nation’s highways

would be survivable if the Soviets were unable

to keep track of the location of each vehicle.

This section first analyzes Road Mobile as a

concept and then describes the special problems which arise when the concept is applied

to a very large missile like the MX.

Road Mobile Concept

Each missile-carrying vehicle would travel in

a convoy of perhaps five vehicles with a total

crew of 10 to 12 people. The other vehicles

would carry security equipment to defend the

nuclear weapons against terrorism, sabotage,

etc., and communications equipment to keep

them in continuous contact with commanders.

One hundred convoys, each consisting of two

missile-carrying vehicles, two security vans,
262 ● MX Missle Basing

and one communications van, might be required for a deployment of 200 MX missiles.

The U.S. Interstate Highway System consists

of 42,500 miles of 4-lane highway, not all of

which is open to traffic. 1 n addition, there are

81,000 miles of other 4-lane highway, of which

28,000 miles are located near heavily populated urban areas. About 80,000 miles of 4-lane

highway located away from populated areas

might be available for Road Mobile MX operat ions.

Survivability y

Little of a definite nature is known about the

effects of nuclear weapons on road vehicles,

but there is agreement that a hardness rating

of 15 psi is probably an absolute upper limit,

with a more reasonable hardness range being 5

to 10 psi. The principal mechanism of destruction might be overturning of the vehicle by the

high winds that follow the shock wave from a

nuclear detonation, To alleviate this problem,

one couId put stakes in the ground and lash the

vehicle down shortly before attacking RVS arrived. Other problems for road vehicles might

be thermal flash and radiation doses suffered

by the crews.

A l-MT weapon would destroy a lo-psi vehicle if it exploded closer than about 3 miles

from the vehicle. One thousand l-MT weapons

cou Id therefore destroy every 10-psi vehicle on

a stretch of road 6,000 miles long. To “sweep

clean” the entire 80,000 miles of available U.S.

highway would therefore require 13,000 l-MT

RVS, which is much more than the present

arsenal of Soviet ICBMS is capable of delivering. If the vehicles were 5 psi hard, only 9,oOO

MT would be required; if 15 psi hard, then

18,000 MT would be required.

It is important to recall that what matters in

these barrage attacks is, roughly speaking, the

number of attacking missiles, not the number

of RVS they carry. (Barrage length, not barrage

area, is relevant here; barrage length does not

correlate with EMT, but the results are still

relatively insensitive to fractionation.) Thus,

‘U S Federal Highway Administration, Highway Statistics,

for example, a Soviet SS-18 can “sweep clean”

about the same length of road whether it carries a few high-yield RVS or a larger number of

lower yield RVS. Thus, the survivability of

Road Mobile would be insensitive to Soviet

fractionation.

A barrage attack on the entire U.S. highway

system could cause significant damage to

population and industry even if the attack excluded highways in the immediate vicinity of

large cities. Road Mobile deployment could

therefore conceivably deter the Soviets from

attacking U.S. missiles for fear of U.S. retaliation on Soviet population and industry. On the

other hand, if a “counterforce” war did begin,

the damage to the United States could be considerable.

A theoretical possibility for Soviet attack

planners would be to keep track continuously

off the locations of the Road Mobile convoys

and retarget their missiles on an up-to-the

minute basis. Since the average speed of a convoy might be 40 mph, each convoy could travel no more than 20 miles in the minimum possible ICT of a half hour. If the Soviets were

capable of this ideal ICT, they would only have

to barrage 2,000 miles of highway to destroy

all 100 convoys. For this attack, 330 l-MT RVS

would suffice. If the ICT were 1 hour, 660 RVS

would suffice, and so on.

Cloud cover over the United States and U.S.

countermeasures would make reliance on

space-based surveillance a risky course for the

Soviets. Human agents capable of tracking the

convoys or attacking them directly would also

be a possibility.

Advantages and Disadvantages

in summary, the principal advantages of the

Road Mobile concept are its high survivability

in the absence of continuous tracking, the insensitivity of its survivability to Soviet fractionation, independence from warning, little

environmental impact, and — at least from

some points of view on deterrence— an unclear distinction between attack on U.S strategic forces and attack on U.S. value.
Ch. 8—Land Mobile MX Basing ● 263

A principal disadvantage of Road Mobile

would be the exposure of nuclear weapons

traveling the Nation’s highways to accidents,

public interference, sabotage, and terrorism.

Though probably difficult to implement in

practice, and subject to U.S. countermeasures,

a system for continuous tracking and targeting

of Road Mobile convoys would allow the Soviets to destroy a Road Mobile force. Finally, attack on Road Mobile could, depending on the

highways used, cause substantial collateral

damage to U.S. population and industry.

Minimizing accuracy degradation relative to

that planned for fixed land-based deployment

might require pre-surveying of thousands of

launch points along the nation’s highways or

provision of external navigation aids.

The Problem of Missile Size

The discussion so far has been confined to

the concept of Road Mobile missile basing.

The problems of actually implementing this

concept with the large MX missile would be

severe. The vehicle needed to carry MX would

exceed by large margins not only the legally

permitted loads on the Nation’s highways but

quite probably the physical tolerances of

bridges and underpasses.

According to a rough rule of thumb for design of heavy road vehicles, the gross weight of

a loaded vehicle is about twice the weight of

the load. The MX missile and its support and

launch equipment might weigh 250,000 to

300,000 lb, meaning a 500,000- to 600,000-lb

Road Mobile vehicle. To distribute this weight,

even with modern independent suspension,

could require some 20 axles with 8 wheels

each, spaced 8ft apart for a total vehicle

length of some 160 ft. By contrast, the maximum load permitted by any State, even with a

special permit, is only 100,000 lb, and large

tractor-trailers weigh half this amount. The

largest load ever moved long distance over the

Nation’s highways weighed only 335,000 lb and

traveled only in good weather. z Since the

weight of an MX carrier would exceed by large

margins the loads for which highway over-

~ Transportation Engineer Magazine, February 1980

passes and bridges are designed, it cannot be

said with assurance that these structures could

support them.

Size of the vehicle would also be a problem.

A large beam under the bed of the vehicle

would be needed to support the heavy load.

Vertical clearance on Interstate Highway underpasses is nominally 16 ft, but many older

segments of the system have only a 14-ft clearance. A Road Mobile MX vehicle would probably be too tall to fit under these underpasses.

Thus, the large size of the MX missile makes

Road Mobile MX a practical impossibility.

Road Mobile MX: Disperse-on-Warning

An alternative to keeping missile-carrying

vehicles in continuous motion would be to

base them at existing military installations and

have them disperse onto the highways when

given warning of Soviet attack.

For an average vehicle escape speed of 40

mph given tactical warning only, the vehicles

could be at most 20 miles from their bases

when Soviet RVS arrived. The Soviets would

therefore only have to barrage the highways

within a 20-mile radius of each base to destroy

all the vehicles. If the vehicles were 10 psi

hard, then a few tens of l-MT RVS would suffice for this barrage.

If the vehicles were given more warning

time, then they could disperse over more road.

With about 6 hours of warning time, the vehicles could be dispersed over so much road that

a Soviet barrage could not destroy al I of them.

Disperse-on-Warning Road Mobile would

therefore require hours of warning time to survive. If attack were to come with Iittle or no

advance warning, the force would be destroyed.

Even given ample advance or “strategic”

warning of imminent Soviet attack, there

could be concern for the reaction of the U.S.

public and the Soviet Union to dispersal of the

vehicles from their bases. Thus, there might be

inhibitions on the part of U.S. authorities to

disperse the force until the evidence of imminent Soviet attack was absolutely convincing.
264 MX Missile Basing

By then it could be too late to guarantee survival of the force.

Traffic might also impede the escape of a

Disperse-on-Warning force.

Last, the same problems of missile size

would obtain as for Continuously Dispersed

Road Mobile.

Off-Road Mobile MX

Off-Road Mobile would be a system of

wheeled, tracked, or ground-effect vehicles

capable of travelling over relatively rugged terrain. By dispersing over a large area and

following random paths, such a sytem would

force the Soviets to barrage the entire deployment area to destroy the missiles. The success

of such a barrage attack would be insensitive

to Soviet fractionation.

Off-Road Mobile would require a large

amount of land for deployment, and the random movement of the large, heavy vehicles

would make off-road operation destructive of

the deployment area. If the vehicles were 15

psi hard (a quite high value), then a single l-MT

RV could destroy every vehicle in a 16-mi2 area

about the detonation point. Three thousand

RVS could destroy every vehicle in a 48,000-mi2

area. To guarantee 50-percent survival of an

MX force against such an attack, a total deployment area of 96,000 mi2 would therefore

be required. If the vehicles were only 10 psi

hard, then 150,000 miz would be needed.

For comparison, the area of the State of

Utah is 85,000 mi2

, of Texas 267,000 mi2, and of

Alaska 590,000 mi2

. The total amount of land

owned by the Departments of Defense and Energy in the Southwest (including Nellis Bombing and Gunner y Range, Yuma Proving

Ground, White Sands Missile Range, and Fort

Bliss Military Reservation) is about 17,000 mi2

.

An Off-Road system that did not occupy the

entire dispersal area at all times, but flushed

from central operating bases on warning,

would be vulnerable to surprise attack in the

same manner as Disperse-on-Warning Road

Mobile. The consequences of false alarm dispersal could be serious if the dispersal area

were normally used for peaceful purposes,

since the vehicles would be quite destructive

of the terrain.

As in the case of Road Mobile, design of

vehicles to carry the large MX missile safely

over rough terrain would be chalIenging.

Dash-to-Shelters

A large dispersal area would be required for

Off-Road Mobile because the vehicles would

be relatively soft targets, of order 10 to 15 psi.

The deployment area could be contracted by

providing many harder garages or shelters

throughout the deployment area. The vehicles

wouId take refuge in the shelters shortly before

attacking warheads arrived. Such a system

would in fact be a multiple aimpoint system,

since the Soviets would target each shelter

individually rather than bombard the whole

area.

The Dash-to-Shelters concept can be seen as

a precursor of the MPS system with PLU such

as presently under development by the Air

Force. A Dash-to-Shelters system would force

the Soviets to target all the shelters, since the

missile transporter would not choose which

shelter to dash to until it received warning that

a Soviet attack was underway. Success of this

system would therefore depend upon reliable

warning. The same objective of forcing the

Soviets to attack each shelter could be attained, and the dependence on warning removed, by emplacing the missiles in the

shelters before the attack but concealing

which shelter actually received the missile.

This approach would of course be the MPS

concept with PLU.

Rail Mobile MX

Rail vehicles to carry the large MX missile

couId probably be built much more easily than

large wheeled vehicles. Like road vehicles, the

rail cars wouId be vulnerable to overturning by

the strong winds that follow a nuclear blast

wave. The hardness of a rail vehicle would

therefore be in the region of 10 psi, though

lashing down the vehicle might result in
Ch. 8—Land Mobile MX Basing ● 265

greater hardness. A l-MT RV could therefore

“sweep clean” some 6 miIes of rail.

There are about 200,000 miles of rail route in

the United States. The length of track is larger,

since many routes consist of several parallel

tracks. Many of these rail routes are in the

vicinity of large population concentrations, so

a smalIer length of route— perhaps 100,00 0

miles—would be available to a Rail Mobil e

MX force. This is more track than could be barraged by any foreseeable Soviet arsenal.

The rail vehicles would have to have rightof-way on the tracks, since their survival would

depend on their ability to choose their itineraries randomly. Since most intercity rail routes

such as those that would be used for the missile force consist of only one track, they are

already quite congested. Trains must be routed

into sidings to allow others to pass, and so on.

Military commanders would therefore be dependent on civilian rail operators and workers

for the day-to-day operations of the force.

Rail Mobile missiles would also be subject

to accidents, sabotage, and terrorism.

83-477 10 - 81 - 18
Chapter 9

DEEP UNDERGROUND BASING
Chapter 9.— DEEP UNDERGROUND BASING

L

figure No.

stof figures

116 Postattack Egres s

117, Mesa/Tunnel Concept Section View

11 Tunnel Boring Machine

119. Aerial View of Mesa-[ la<

120 Mesa/Tunnel Concept P

121. Transporter Lau

122 Missile Launch

123 [and Area Requirements

Base force

a n V i ew Schemati c

Requirments
Chapter 9

DEEP UNDERGROUND BASING

000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000One interesting concept for missile basing is

the deployment of the missile force in deep

mountain in tunnels, buried thousands of feet

under the surface, thereby providing protection for the missiles from a nuclear attack.

Such a facility would be manned and would

have self-contained provisions for electrical

power, life-support, and missile maintenance.

Upon the command to launch, tunnels would

need to be bored to the surface to give the

missiIe outside access preparatory to being

launched.

The limitations of such a missile deployment

derive not from the technicaI feasibiIity of its

construction, but from the time constraints of

a reliable missiIe egress for Iaunch A sc hem,] t i c for two types of missiIe egress is i1-

Iustrated in figure 116A and B shows a number

of completed vertical exit passages that are

preconstructed. Missile egress through these

passages could be rapid, but the exit portals

could be easily attacked with nuclear weapFigure 116A. —Postattack Egress

I I

116B

1

l - - I

SOURCE” Office of Technology Assessment

ens, which would deny then the ability to

launch the missile. Even “hardened” exit portals would be vulnerable with today’s missile

accuracies. Moreover, attempts at constructing hidden exits wouId rely totalIy on keeping

their locations secret for the entire course of

deployment – a considerable risk

These observations have led to designs for

deep underground basing without preconstructed exits (see fig. 116B). After the order to

launch, large underground tunnel boring

machines would clear a path to the surface

from the partially completed tunnels. This

method of launch would not be rapid, due to

the lengthy excavation process, and couId take

a period of days to perhaps weeks; in the

meantime work continues on devising a faster

method for missile egress.

Clearly, this mode would not be suitable as a

quick-response force for t i me-urgent missions

a f te r the i n i t i a I a t ta c k — amajor sta ted requirement for the MX missile. On the other hand, it

couId play a usefuI part in the overaI I strategic

nuclear force as a secure reserve force. Postattack endurance might be very good, perhaps

a yea r or Ionger. Further more, i t couId have a

stabilizing effect and serve as a deterrent to

war due to its high survivab i I it y to nucIear

attack Unlike fixed missiIe siIos or muItiple

protective shelters, deep underground basing

wouId be relatively insenitive to the increased

accuracy of enemy misiiIes, or the f ractionation of their pay load. Moreover,

deceptive basing of the missiles would be

unnecessary

Although studies of deep missile basing date

back many decades, it is still in a conceptual

stage. Hardware specific to this type of missiIe

basing has not been developed or tested,

a I though m a n y of its components, such as

deep unclerground faciIities and tunnel boring

machines, have been constructed for other

purposes. And, although a large data base on

underground nuclear explosions has been collected over several decades, there is still a

269
270 MX Missile Basing

degree of uncertainty on the coupling of explosive energy of a nuclear surface burst to the

underground. This knowledge would be important in determining the minimum tunnel

depth for sure survival of the missile against a

large nuclear attack.

One concept for deep basing is illustrated in

figure 117. This approach would utilize basing

inside of a mesa, which, due to its relatively

steep slope, has the advantage of providing a

short tunneling length to the mesa face for

missile egress. System burial would be typically several thousand feet. The exit route for the

missile would be partially predug, with the remainder left to be dug by a tunnel boring

reach i ne, after receiving the command to

launch. In addition, a number of horizontal

access tunnels would lead to the underground

complex from the outside. These access tunnels, which would be required during construction, would also provide underground

access during peacetime. Blast doors in these

tunnels would be needed for protection of the

underground complex during an attack. Storage cavities would be provided for crew

quarters, a fuel cell powerplant and its reactants, waste disposal, and tunnel boring machines. (A typical tunnel boring machine is

shown in fig, 118. It is constructed and sold for

tunneling operations.) A reliable means of

assuring a survivable communications link between the outside and the missile force has not

yet been fully developed, although a number

of possible candidate concepts do exist. One

such concept involves the deployment of a

large number of erectable communications antennas, as illustrated in the diagram. Assuring

continuity of this link through the mesa during

periods of attack is still a matter to be fully resolved, since resulting block movements inside

the mesa may break underground cable links.

Figure 11 7.—Mesa/Tunnel Concept Section View (not to scale)

Erectable communications

antenna concepts

SOURCE: Office of Technology Assessment
Ch. 9—Deep Underground Basing ● 271

Figure 118.—Tunnel Boring Machine

SOURCE: Robbins Co , Seattle, Wash.

An aerial view of the underground mesabased force is shown in figure 119. The underground tunnels, shown as broken lines, form a

closed complex around the mesa. An enlargement of a tunnel section is described in figure

120. The missile would be part of a launcher

and transporter vehicle, as shown in figure 121,

that resembles the vehicle used for buried

trench basing, as discussed in chapter 2. For

missile launch, after the tunnel boring machine

cleared the way to the surface, the transportermissiIe-launcher would move through the newly built tunnel to the surface, under its own

power. This is illustrated in figure 122.

OTA has not analyzed either the environmental impacts or scheduIing considerations

for deep basing. A preliminary review does not

indicate the likelihood of insurmountable

problems, however. Estimates for system cost

and construction time are highly tentative at

this time. Much work on the detailed concept

(particularlyC 3

), research and development,

and validation of design would be needed.

Moreover, delays in construction for this

basing mode could be expected, as experience

in previous underground excavation projects

indicates unexpected geological conditions

that hamper progress. On the other hand,

much excavation experience is available from

many commercial and civil projects. Land area

requirements are likely to be relatively small.

Shown in figure 123 is a map of the United

States with deployment areas of the Minuteman missile fields, the proposed MX/MPS deployment area, and two candidate basing

areas for deep underground basing, one in the

area of Grand Mesa, Colo., and an alternative

site in southern Utah.
272 ● MX Missile Basing

Figure 119.—Aerial View of Mesa-Based Force

SOURCE: Office of Technology Assessment

Figure 120.—Mesa/Tunnel Concept Plan View Schematic
Ch. 9—Deep Underground Basing ● 273

Figure 121.—Transporter Launcher

Length - 35m (115 ft)

Width - (11.5 ft)

Height , (17.5 ft)

Weight 135,000kg (300,000lb

Drive motors (3) 350hp each

SOURCE Off Ice of Technology Assessment

Figure 122.— Missile Launch

’

1,

i

Missile launch

Transporter

launcher

mesa face

tunnel (200/0

upgrade)

Bed rock

SOURCE Off Ice of Technology Assessment

Chapter 10

COMMAND, CONTROL, AND

COMMUNICATIONS (C3

)
Chapter 10.– COMMAND, CONTROL,

AND COMMUNICATIONS

Page

Overview. . . . . . . . . . . . . . . . . . .277

Technical Aspects of Strategic C3 . . . . . . . . . . . . . . .278

Communications Links. . . . . . . . . . . . . . . . . . . . . . . . . . . . .278

Vulnerabilities of Communications Systems, . . . . . . . . . . . .281

Command and Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ......283

C Functions for MX Basing. . . . . . . . . .284

Preattack Functions.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .,......284

Transattack and Postattack Functions. ., . . . . .285

C

) SystemsforMX Basing Modes . . . . . . . . . . . . . . . . . . . . . . . . . . ...........285

f3aselineMPS System . . . . . . . . . . . . . . . . . . . . . . . . . . . . ., ....286

MPS 13 asing With LoADS ABM System. ......,. . . . . . . . . . . . . .......,289

Launch UnderAttack. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. ....290

Small Submarines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...290

AirMobileMX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...293

Overviewof Radio Communications. . . . . . . . . . . . . . . . . . . . . . . . . . . . ...294

RadioWavePropagation . . . . . . . . . . . . . . . .,..,. 294

Disruption of Radio Communications Due to Nuclear Detonations ............296

TABL E

Table No.

34. Radio Communications Bands. . . . . . . . . . . . . . . . . . . . . . . . . .......,.279

124

125

126

127

128

129

130,

131

132.

133.

134,

135.

136

137

138

139

140

FIGURE S

Figure No

Communications System for Baseline MPS System (Transattack) ...,286

Possible Additions to Baseline MPS Communications System (Transattack). 288

Communications System for Baseline MPSSystem (Postattack) . ....288

Possible Additions to Baseline MPS Communications System (Post attack). .289

Preattack C) System for Small Submarines . . . . . . . . . . . . ....291

Transattack C’ System for Small Submarines . . . . . . . . . . . . . . . . .......292

PostattackC’ System for Small Submarines......................................293

Transattack AirMobile MX Communications System ..29 4

Physical Paths of RadioWaves .. . . . . . . . . . . . . . . . . ...295

Electromagnetic Transmission Ranges at Different Frequencies . . . .295

Over-the-Horizon Radio Transmission . . . . . . . . ..296

Geometry of Aircraft Direct Path Communications.. . . . . . . . . .. ....296

Geometry of Satellite Communications . . . ...297

Electromagnetic Pulse Ground Coverage for High-Altitude

Nuclear Explosion . . . . .................................................................................. . . . . . . ..297

Origin of Electromagnetic Pulse From High-Altitude-Nuclear Explosion. . .298

Atmospheric Radio Propagation at Different Frequencies. . . ........... 299

Radio Propagation Paths Before and After High-Altitude-Nuclear Explosion 299
Chapter 10

COMMAND, CONTROL, AND

COMMUNICATIONS (C’)

OVERVIEW

A missile force that physically survives an attack is of no use if the means to command the

force do not survive as well. Reliable command, control, and communications (C3

, pronounced “C-cubed”), impervious to Soviet attempts at disruption, are needed if commanders are to assess the status of an MX force,

retarget the missiles if desired, and transmit

launch commands. There is a wide variety of

technical possibilities for wartime communications and just as wide a range of means to disrupt and impede them. The nature of the disruption suffered by the U.S. C3 system in wartime would depend on the amount of damage

done to communications installations themselves and on the extent of disturbance of the

atmosphere due to nuclear explosions. Though

some disruption would inevitably result regardless of the nature of the Soviet attack, the

most stressing circumstance would result from

a deliberate Soviet attempt to deny U.S. commanders the means to control and execute

their forces.

It will be apparent that no single communications link can be made absolutely survivable, but disruption can be made difficult,

time-consuming, provocative, and costly of

Soviet resources. Multiple links can also be

provided, subject to different failure modes,

and provision can be made for reconstituting

some links if the primary system is destroyed.

The actual functions that a C3 system supporting an MX force must fulfill depend to

some extent on doctrine for the force’s use. At

a minimum, the communications system must

be consistent with the operations of the force

(e.g., must not compromise missile location in

multiple protective shelter (MPS) basing or

submarine location in submarine basing) and

must permit one-way communication of short

launch commands (Emergency Action Messages— EAMs) from commanders to the missiles to order execution of preplanned options

of the Single Integrated operational Plan

(SIOP). In addition, it could be desirable for

the C3 system to support prompt response to

launch commands (“responsiveness”), flexible

or ad-hoc retargeting outside of the SIOP, and

two-way communications so that the forces

could report their status to commanders and

confirm execution of orders. Last, if the force

expected attrition in an attack, it could be desirable for the surviving missiles to be able to

redistribute targets among themselves so that

the highest priority targets were always covered by surviving missiles. For a given basing

mode, the hardware to carry out these functions, and the functions themselves, can differ

substantially from the preattack or peacetime

period to the transattack and postattack

periods.

OTA has sought to prescribe a technically

feasible C3 system that satisfies these criteria

for each of the principal basing modes. In

many cases the system described differs substantially from those that are available to U.S

forces today. Obviously, providing these systems would involve some cost, but with the exception of launch under attack, in no case is C3

a cost driver for the basing mode as a whole.

Some elements of these C3 systems would furthermore support other strategic and conventional forces, so their costs should perhaps not

be assigned entirely to the MX basing mission.

There are distinct and important differences

from basing mode to basing mode regarding

both the technical means to support effective

C

3 and potential vulnerabilities. In each case it

appears that with adequate funding and effort,

acceptable technical solutions are available,

though it would be extremely difficult to provide a C3 system survivable against any and all

contingencies. Direct comparisons are difficult, but on balance OTA can see no clear rea277
278 ● MX Missile Basing

son for preference among the basing modes on in concrete terms the functions desired from a

the basis of C3

. C

3 system supporting MX basing. The next section describes the C3 systems for the basing

The next section discusses the technical as- modes and describes how they might function

pects of strategic C’ in general terms, including before and after attack. The last section conavailable means of communication and their tains a technical overview of radio communivulnerabilities. The following section lays out cations.

TECHNICAL ASPECTS OF STRATEGIC C3

Communications Links

The communication of information between

two points requires an intervening communications link. For instance, a telephone microphone converts acoustic signals (i.e., a human

voice) into electrical signals, and the earphone

converts the electrical signal back into sound.

The lines over which the signal travels between

the phones is referred to as the communications link. By bouncing radio waves off the

ionosphere, it is possible to communicate over

very great distances. in the case of this type of

communications, the path over which the radio wave travels is the communications link.

At very high radio frequencies, radio waves are

not reflected by the ionosphere. In order to

achieve long-range communications in this

case, it is necessary to transmit the signal to a

satellite that then retransmits it back to Earth.

The channel established through the satellite is

called the communications link. This seemingly expensive and complex method of radio

communications is valuable for two reasons:

1. Satellite communications links can

2

achieve high data rates relative to radio

communications that require reflection

from the upper atmosphere.

Satellite links, if they are not destroyed,

are extremely reliable, since communications capabilities do not change with the

fIuctuating conditions in the upper atmosphere.

The time it takes to transmit a message of a

given length over a communications link is

determined by the data rate of the link. Any

message, whether transmitted by voice, teletype, or picture, can be expressed as a sequence of “on or off” signals called bits. The

data rate is the number of bits per second that

can be transmitted over a particular link. Teletype rates are typically a few hundred bits per

second. Since each sequence of five to seven

bits would be enough to represent a letter of

the alphabet, and since on the average there

are five letters per word of the English language, a 300 bit-per-second teletype link could

carry 8 to 12 words per second. Voice communications require data rates of several thousand bits per second. High-frequency satellite

links can transmit data at hundreds of millions

of bits per second. These data rates could support tens of thousands of separate voice channels. A particularly important type of message

in the case of strategic C’ is the EAM. These

messages, ordering a strike by U.S. strategic

forces, could be preformatted and might consist of a small number of bits, since even a format with a small number of bits would lead to

a large number of possible messages that

could have the same format. For instance, if

EAMs consisted of 20 bits, then more than a

million different messages with the same format could be created. EAMs can therefore be

very short messages and can be transmitted in

a short time even by links with relatively low

data rates. Much more information would

have to be transmitted to order a strike that

was not among the preplanned options. A high

data-rate link would be required to transmit

such long messages in a short time.

Land lines

Landlines consist either of wires that conduct electricity or of glass fibers (i.e,. fiberoptic) through which light can be guided.
Ch. 10—Command, Control, and Communications (C3

) . 279

Both types of Iandlines can be used for extremely high data-rate communications and

are therefore very useful for communicating

with land-based strategic weapons systems,

The communications Iinks and nodes associated with Iandlines, however, are vulnerable to

physical destruction in war and are subject to

disruption or destruction by electromagnetic

pulse (EMP) generated by high-altitude nuclear

bursts. Landlines might therefore only be of

use before an attack on a land-based strategic

weapons system.

Radio Links

Radio communication bands are, by convention, referred to by acronyms. Since these

acronyms are commonly used in discussions of

communications systems, they are summarized in table 34.

VLF/LF

Very low frequency (VLF) and low frequency

(LF) radio signals are useful for reliable communication over very large distances. A powerful VLF/LF station can be received over distances of many thousands of miles, even if

there are nuclear detonations in the upper atmosphere. VLF/LF signals penetrate seawater

well enough to make communications possible

with submarines and, at a cost in data rate, can

be made resistant to jamming. VLF/LF radio

has two important drawbacks: the antennas required for transmission and reception must be

very large and are therefore susceptible to

physical destruction, and the data rates that

are possible with VLF/LF are low. However, airplanes are able to trail large antennas in flight

and transmit sufficiently powerful VLF/LF

radio waves to permit long-range communications. Airplanes can communicate with

ground stations, other aircraft, and submerged

submarines in this way.

M F

Medium frequency (MF) radio links are higher frequency than VLF/LF radio links and can

be used to transmit information at higher rates

than is possible with VLF/LF. (The reason for

this and other features of radio propagation is

discussed in the Overview of Radio Communications section. ) MF radio is in the same band

of frequencies as AM radio broadcasting. Like

AM radio, MF signals do not, under normal

conditions, propagate much further than the

length of a metropolitan area, though at night

skywave propagation can lead to longer range.

MF is a reliable means for moderate data-rate

transmissions over short distances. Since the

radio signals at these frequencies do not travel

very far, they are generally (but not always) difficult to jam from great distances. Distances

over which communications at these frequencies can generally be affected are 40 to 50

miles between ground stations and 100 to 150

miles between an airplane and a ground station.

H F

High frequency (HF) (“short wave”) radio

signals are extremely useful for long-range

Table 34.—Radio Communications Bands

Name of Range Frequency Range* Wavelength Range

Extremely low frequency ELF .3-3 KHz 1,000-100 km

Very low frequency VLF 3-30 KHz 100-10 km

Low frequency LF 30-300 Kfiz 10-1 km

Medium frequency MF 300-3,000 KHz 1,000-100 m

High frequency HF 3-30 MHz 100-10 m

Very high frequency VHF 30-300 MHz 10-1 m

Ultra high frequency UHF 300-3,000 MHz 100-10 cm

Super high frequency SHF 3-30 GHz 10- 1 cm

Extremely high frequency EHF 30-300 GHz 1 -.1 cm

“Hertz = cycle per second, KHz= KiloHertz = 1,000 cycles per second, MHz= MegaHertz = 1,000 KHz,

GHz = GigaHertz = 1,000 MHz.

tm = meter= 328 feet, km= kilometer= 1,000 meters= .6212 miles, cm = 01 meters= 394 inches.
280 ● MX Missile Basing

moderately high data-rate communications. In

contrast to VLF/LF radio systems, HF equipment and antenna systems are compact and do

not require large amounts of power. A serious

problem with HF band communications is that

they are easily disrupted by nuclear detonations in the upper atmosphere, and can be

“blacked out” over very large distances for

periods of hours. Another problem with HF

communications is the possibility of using

direction finders to determine the location of

the transmitter well enough to attack it. A

possible further problem with HF is that the

number of usable frequency bands is limited.

Many users trying simultaneously to use HF

could jam one another.

In spite of these drawbacks, the upper atmosphere would recover electrically several

tens of hours after nuclear detonations occurred and would then be able to support the

long-range transmission of HF. For this reason,

HF would be useful for an indefinite period

after a nuclear attack for high-data-rate communications even if other communications

links were destroyed.

Today’s fielded HF systems require manual

tuning, introducing some unreliability even in

day-to-day peacetime communications. Microprocessor-tuned HF systems resulting from

technology improvements would make HF

highly reliable except in periods of significant

blackout.

VHF

Very high frequency (VHF) waves are not

strongly reflected from the upper atmosphere

and do not travel far over ground. VHF is the

band at which FM radio broadcasts occur, and

it is familiar to radio Iisteners that FM stations

have shorter range than AM stations. Very high

data rates are possible with VHF, and antennas

and equipment can be made compact.

Long-range communications are possible

using VHF by reflecting radio signals off the

ionized trails of meteors. Since it is necessary

to have a reflecting meteor trail in the right

location of the upper atmosphere to permit

communications between two points beyond

the radio horizon, delays of a few minutes

could occur before it would be possible to

transmit a message using VHF. One possible

advantage of VHF is that it might be possible

to communicate effectively by bouncing radio

signals off the bottom of the ionized region

formed by a high-altitude burst. Thus, VHF

communications might actually be improved if

the Soviets blacked out HF or UHF.

UHF

Ultrahigh frequency (UHF) is extremely useful for line-of-sight communications between

aircraft. The data rates are high and the equipment is quite compact and low power. UHF

can be used to communicate to ground installations from an aircraft at a distance of about

200 miles and can be used to communicate

between aircraft at distances between 300 and

450 miles. For this reason, UHF could be used

to communicate between airborne command

posts and to transmit launch commands to

land-based missiles.

It is possible to use direction-finding techniques to locate UHF transmitters and it is also

possible to jam receivers This problem is unlikely to be serious for line-of-sight aircraft

communications but it could be a problem for

UHF links through satellites.

Satellite Communications (SATCOM)

UHF SATCOM

UHF satellite links are useful not only

because data rates can be very high, but also

because UHF antennas are not extremely directional, so users do not have to have means

for pointing antennas at satellites. A drawback

of UHF SATCOM links is that it is possible to

jam the uplinks to the satellites from small

mobile jammers (ship or ground mobile) located anywhere in the satellite’s hemisphere of

view. A problem associated with the multidirectional nature of UHF signals is that

enough signal can be “seen” from other directions that it is in principle possible to locate

ground-based UHF transmitters from space.

Nuclear detonations in the upper atmosphere

can also result in “blacking out” of UHF
Ch. 10—Command, Contro/, and Communications (C3

) 281

signals for a few hours over regions of the

Earth’s surface. These regions of blackout

would have radii of tens to hundreds of miles.

The United States now uses UHF SATCOM reguIarly for worldwide mi1itary communications.

UHF satellites could be launched from silos

into low orbit in wartime to reconstitute disrupted I inks.

SHF/EHF SATCOM

Super high frequency (SHF) and extremely

high frequency (EHF) satellite links are extremely useful for very high data rate, reliable

communications. Because of the large bandwidth, such links are, at least for EHF, unjammable. Because the wavelengths are so short

(on the order of fractions of a centimeter), it is

possible to have very highly collimated radio

beams that can be trained on the satellite. In

addition, SHF/EHF antennas are sufficiently

small (about 5 inches in diameter) that they

can be conveniently mounted on ground vehicles, aircraft, surface ships, and submarine

masts.

Since the SHF/EHF beam is so tightly collimated, it is nearly impossible for a receiver

that is not in the beam to “see” the signal. The

only way that the presence and location of an

SHF/EHF transmitter could be detected would

be if the search receiver was itself in the beam.

Thus, SHF/EHF satellite uplinks from forces in

the field, surface ships, and submarines would

not pose the risk of revealing the location of

the transmitters.

A potential problem with SHF/EHF is an atmospheric phenomenon called scintillation.

Electron density fluctuations in the ionoshere

due to high-altitude nuclear bursts could cause

the beam to be bent as it propagated through

them. This bending would result in fluctuations in the quality of reception at the receiver.

It is believed that with suitable signal modulation scintillation would not be a problem at all.

For EHF, scintillation would not last, in any

event, for more than a few minutes after a

high-altitude burst. Another minor problem is

that water absorbs EHF signals. However, a

major rainstorm would be required to impede

communications. Mist and clouds would not

be a problem.

LASER SATCOM

The high frequencies and directional nature

of laser communication allow for extremely

high-data-rate, low power consumption, unjammable links between satellites and between satellites and aircraft flying above the

clouds. Communications between ground stations and satellites would not be feasible

because of the possibility of cloud cover. Even

in clear weather, such communications would

create a visible pencil of light in the sky,

revealing the location of the user. For this

reason laser SATCOM might endanger the covertness of submarines, surface ships, and

mobile ground units.

Vulnerabilities of

Communications Systems

Physical Destruction

One obvious way to attempt to deny communications capability to U.S. strategic forces

would be to physically destroy as many susceptible elements of the system as possible.

This destruction would include landlines, landline switching stations, radio transmitter stations (i.e., VLF/LF/MF, etc.), satellite up-anddown-link stations, and fixed command centers

After an initial attack, it could not be

guaranteed that landline communications

would exist with land-based forces or that

fixed VLF stations would be broadcasting to

the submarine forces. Only communications

links made possible with aircraft and satellites

would necessarily still be intact.

Electromagnetic Pulse (EMP)

An effect of the detonation of nuclear

weapons, both inside and outside the atmosphere, that is less appreciated but still very

important is EMP. The case of a detonation

outside of the atmosphere is, however, the

most relevant as a general problem for communications systems.

83-477 0 - 81 - 19
282 ● MX Missile Basing

As explained in the Overview of Radio Communications section, a high-altitude nuclear

detonation could generate a sudden electric

field over large regions of the United States of

up to 50,000 volts/meter. This intense electric

field could destroy or disrupt communications

and electrical equipment of all types. High

quality assurance and testing are required to

ensure that components are properly sealed

and protected if they are to survive the effects

of the EMP from high-altitude detonations.

Ionospheric Disruption

Another effect of high-altitude nuclear

detonations is ionospheric disruption. The

electron densities in the ionosphere would be

changed suddenly by the ionizing effects of

prompt gamma rays from the nuclear detonation and/or beta rays from fission decay products. These effects could cause significant

degradations at those radio frequencies that

are reflected from (HF) or pass through (UHF

SATCOM) the ionosphere.

Jamming

Jamming refers to the ability of a hostile

transmitter to drown out the signal being received. The susceptibility of a radio link to

jamming depends on power, bandwidth, modulation technique, and antenna directivity. In

general, jamming becomes more difficult as

the frequency of the transmission increases. If

the nature of potential wartime jamming can

be foreseen, it can be compensated by changes

in modulation technique and increases in

power.

Ant i satellite (ASAT) Threats

There is considerable concern that the heavy

dependence of the U.S military on SATCOM

will make satellites the targets of attack. The

means of attack could be direct-ascent interception, space mines, land-based lasers, or

even space-based lasers.

Several of the basing modes discussed in this

report could make effective use of SATCOM.

A highly reliable SATCOM system based on

deep-space millimeter-wave (E H F) communications has been proposed for military use and

would be very useful to support MX basing.

The following discussion explains why there is

considerable interest in such satelIites.

Though geosynchronous orbit would be

most convenient for such satellites operating

at EHF frequencies, it would perhaps be advisable to deploy them in higher orbits.

Geosynchronous orbit is that unique orbit

22,300 miles from the Earth at which the orbital period of satellites is equal to the rotation

period of the Earth. Thus, satellites in geosynchronous orbits remain over the same point on

the Earth’s surface as both they and the Earth

go around. Because its position relative to the

Earth’s surface would remain the same, users

would have a fixed point upon which to focus

their directional antennas. Because of its convenience, however, geosynchronous orbit is

quite crowded. It would therefore be possible

for the Soviets to station a “space mine” near a

U.S. communications satellite and answer in

response to U.S protests that the mine was in

fact some other sort of satellite that it was convenient to position in geosynchronous orbit.

The United States would then not be in a position to assert that the Soviets had no business

there, because it would be quite plausible that

they did have legitimate purposes for positioning a satellite in this unique, convenient orbit.

If on the other hand the U.S. satellites were

in an orbit chosen more or less randomly from

among the infinite number of possible altitudes, the United States would be in a better

position to assert that the only possible purpose for a nearby Soviet satellite must be to interfere with that of the United States. The

United States might then justify on these

grounds measures against such interference.

Satellites could also be threatened by direct

attack from a missile launched from the Soviet

Union. However, the U.S. satellites could be

positioned high enough that it would take

many hours (18 or so) for an attacking vehicle

to reach them. Furthermore, since the interceptor missiles required to reach high orbits would

be quite large, the Soviets would probably only

launch them from the Soviet Union. Most of
Ch. 10—Command, Control, and Communications . 283

the U.S. satellites would be on the other side of

the Earth when the first interceptor was

launched, and launch of other interceptors

would have to be staggered to intercept the

rest of the satellites as they “came around. ”

Direct-ascent antisatellite attacks on high orbits would therefore present a timing problem

to the Soviets. The United States would certainly be aware that the satellites were under

attack hours before they were destroyed.

Last, land-based lasers could not deliver sufficient power to the orbits of interest (five

times geosynchronous or so, or half way to the

Moon) to destroy the satellites.

A number of measures could be taken to ensure the survival of these satellites. For instance, they could be provided with sensors to

allow them to determine when they were under

attack, and they could maneuver to avoid

homing interceptors and deploy decoys or

chaff to confuse homing sensors. Backup

satellites at such distances from the Earth

might also be able to be hidden entirely by giving them small optical, infrared, and radar

signatures. Dormant backup satellites might

be hidden among a swarm of decoys and

turned on when the primary satellites encountered interference. Last, backup satellites

(probably using UHF instead of higher frequencies) couId be deployed on missiles in silos and

launched into low orbits to replace the primaries. These reconstituted satellites could

also be attacked, but it would take time for the

Soviets to acquire data on their orbits, even

assuming the United States allowed them unhindered operation of the means to acquire

this data. Some of these techniques for satellite security are more effective than others.

Command and Control

This chapter deals for the most part with the

communications aspect of C3

. The command

and control functions for U.S. strategic forces

are outside the scope of this discussion, but it

is necessary to specify how the command

structure is linked to the communications system and thus to the forces.

Decisions regarding the use of U.S. strategic

forces are in the hands of the National Command Authorities (NCA), i.e., the President and

Secretary of Defense or their successors. The

military provides a National Military Command System to support NCA. This system consists of fixed command centers and survivable

mobile command posts. The fixed ground centers include the National Military Command

Center in the Pentagon, an Alternate National

Military Command Center at a rural site outside Washington, D. C., the underground command center at Strategic Air Command (SAC)

headquarters at Of futt Air Force Base in

Omaha, Nebr., and North American Aerospace

Defense Command headquarters in Cheyenne

Mountain, Colo.

Since the fixed ground centers could be destroyed early in a nuclear war, a fleet of survivable Airborne National Command Posts is

provided for postattack command and control.

The most important aircraft in this fleet is the

E-4B (modified Boeing 747) National Emergency Airborne Command Post (NEACP, pronounced “kneecap”) available for Presidential

use. In addition, there is a fleet of strip-alert

aircraft at military bases throughout the country, including command posts of the nuclear

commanders and the Post-Attack Command

and Control System (PACCS) fleet. This fleet

could establish a network of line-of-sight UHF

communications from the Eastern to Central

United States within a short time after an attack. Finally, SAC maintains an EC-135 (modified Boeing 707) command aircraft, called

“Looking Glass,” on continuous airborne

patrol over the United States.

Ground-mobile command posts–disguised

as vans traveling the Nation’s highways to

avoid being targeted — are also a possibility for

survivable command posts.

In the descriptions that follow of possible C3

systems for each of the basing modes, it will be

assumed that all force management functions

and launch commands originate with, or pass

through, the airborne or grounded NEACP, and

that NEACP is provided with the necessary

communications systems to link them with the

MX force.
284 ● MX Missile Basing

C’ FUNCTIONS FOR MX BASING

This section outlines the functions desired

of an MX C3 system to support the various

aspects of U.S. Nuclear Weapons Employment

Policy. These policy aspects are associated

with such terms as Basic Employment Policy,

Flexible Response, Quick Reaction Hard-Target Counterforce, Secure Reserve Force, and

the like, as derived from the public statements

of senior defense officials. This section translates these notions into concrete functions required of a C3 system for MX. The next section

will prescribe hardware capable of performing

these functions for each basing mode.

These functions, and most certainly the

means to accomplish them, differ among the

preattack, transattack, and postattack periods.

For the purposes of this chapter, the transattack period is defined as the period of airborne operation of certain C3 aircraft (N EACP,

Airborne Launch Control Center (ALCC),

TACAMO, etc.). The distinction between transattack and postattack as used here therefore

concerns the hardware available to accomplish the C3 functions and not the functions themselves. Transattack and postattack

functions will therefore be treated together.

Preattack Functions

Peacetime Operations

Peacetime communications are required for

commanders to assess continuously the status

and readiness of the MX force. Continuous

one-way communications from commanders

to the forces is an obvious requirement. Twoway communications — including from the missile forces to commanders— is clearly important, though intermittent report-back (relevant

for the case of submarine basing) might be

adequate.

Since the communications links have suffered no damage, the only impediment to

maintaining adequate peacetime communications would be the requirement that the means

of communications should be consistent with

the operations of the force. Thus, the peacetime communications should not be of such a

nature as to compromise missile locations in

the case of MPS basing or defense unit locations in the case of the MPS/LoADS (low altitude defense system) combination, nor betray

the locations of patrolling subs in small submarine basing.

Responsiveness

In the event that NCA ordered the launch of

the MX missiles according to one of the preplanned options of the SIOP before the force

had suffered attack, all that would be required

of the C3 system would be the capability to

transmit a short, preformatted, encrypted

message to the MX force. Since the message

would be short, low-data-rate communications

would suffice.

There could be a requirement that missile

launch be accomplished rapidly after the decision to launch was made. This could be the

case if a Soviet attack were believed imminent

and it was thought desirable to strike Soviet

forces before they could attack the United

States or disperse from their home bases. This

requirement of responsiveness would seek to

make the time interval between dissemination

of the EAM ordering launch and actual missile

launch as short as possible. A portion, though

not necessarily most, of this time interval

would be comprised of the time it took for the

relevant communications links to transmit the

short EAM to the MX force with low probability of error.

in order to strike certain hardened targets

such as missile silos, it would also be desirable

to be able to control the arrival times of RVS so

that detonation of one would not compromise

the effectiveness of others (“fratricide”). Such

time-on-target control could be accomplished

by including in the EAM a reference time, relative to which each missile would determine the

arrival time required of its RVS in order to coordinate arrival with RVS from other missiles.

The precise timing would be achieved by coordinating launch time, maneuvers of the missile, and reentry angle.
Ch. 10—Command, Control, and Communications (C3

) ● 285

In addition to short response time, it could

be desirable for the MX force to be able to

communicate back to the commanders in a

short time to confirm successful launch.

Ad-Hoc Retargeting Before Launch

Ad-hoc retargeting refers to the ability to

construct attacks that are not among the preplanned options of the SIOP. Such retargeting

flexibility could involve either rearranging

targets from the extensive target sets already

stored in the MX missile launcher’s memory or

reprogramming the missile with entirely new

target sets. Both situations would require

transmission of larger amounts of data than

contained in the short EAM. In the latter case,

the information would include target latitudes

and longitudes (calculated in the proper coordinate system), reentry angle, timing, and

fuzing.

Since large attack options would likely be

included among the S IOP options, extensive

ad-hoc retargeting might be confined to a relatively small portion of the force, in which case

only that portion need be in a position to

receive such high-data-rate communications.

The portion of the force retargeted would

presumably be required to report back receipt

of the new targets, confirm them, and report

successful launch.

Transattack and Postattack Functions

Prelaunch Damage Assessment and

Reoptimization Within the SIOP

In the event that the MX force suffered attrition in the attack, it might be desirable for the

surviving missiles to reallocate targets in such

a way that the highest priority targets continued to be covered even if the missiles that

originally covered these targets were destroyed in the initial attack.

Commanders would presumably also wish to

know the extent of attrition and remaining

target coverage.

Order for Launch of Preplanned Options

Dissemination of the EAM after an attack

would require that the surviving portion of the

C

3 system support at least one-way low-datarate messages. Report-back confirming successful launch would require two-way communications. It is not clear that the need for

rapid response would always be as great in the

postattack period as in the preattack period.

Ad-Hoc Retargeting

Assignment of entirely new targets to the MX

missiles and confirmation of receipt would require teletype data-rate two-way communications.

C’ SYSTEMS FOR MX BASING MODES

In this section, the problems of providing effective C

3 for each of the principal basing

modes are discussed and technically feasible

solutions identified. In many instances, the C3

system described for hypothetical future MX

basing modes differs substantially from C3 systems supporting present strategic forces. These

systems would have to be acquired at some

cost, though in no case (excluding launch under attack) is the C3 system a major cost driver

for the system as a whole. Moreover, some of

the communications systems described would

be useful for other military missions in addition to MX basing. OTA has only identified

feasible C3 systems and has not attempted to

find a “best” solution. Also, the systems have

not been subjected to the cost tradeoffs that

could occur if a decision were made to deploy

one of them.

The baseline MPS system is in full-scale

engineering development and subject to certain budgetary constraints. it is therefore

natural that the baseline system could be improved on (e.g., with regard to two-way Ionghaul communications) with additional funding.

Since for the other basing modes similar funding constraints have not been applied to the C3
286 ● MX Missile Basing

systems described here, feasible improvements

to the baseline MPS system—available at

some additional cost — are identified.

Baseline MPS System

Preattack

Peacetime MPS C3 operations would be accomplished principally through the fiber-optic

network linking each shelter with the Operational Control Center (OCC) and with other

shelters. Each fiber cable would contain three

lines (one for communications in each direction and one spare) capable of 48 kilobit/second data rates. With such high data rates,

launch orders and retargeting information

could be transmitted in a very short time.

Response time to an EAM would be driven by

operational procedures and by the several

minutes it would take the missile to emerge

from the shelter and erect.

PLU would be maintained by having the missiles and simulators transmit encrypted status

messages with identical formats according to

uniform message protocols.

Transattack

The transattack period is defined in this

chapter to comprise the period of airborne

operation of the ALCC and NEACP. One ALCC

would always be airborne in peacetime, with

another on strip alert. The in-flight endurance

of the ALCC would be about 14 hours, after

which communications would have to be accomplished from the grounded aircraft to the

MPS shelters.

The transattack C3 system for the baseline

MPS system is shown in figure 124.

Communications between the ALCC and

NEACP are relatively secure. Immediately

after the attack, however, the HF and UHF

SATCOM could be disrupted, and it would

take some time to set up the UHF line-of-sight

PACCS net.

Of the links from the ALCC to the shelter, HF

(line-of-sight) could be disrupted by the

nuclear environment, and MF represents a

compromise between the better propagation

of low frequencies through an ionized atFigure 124.–Communications System for Baseline MPS System (transattack)

SOURCE: Office of Technology Assessment.
Ch. 10—Command, Control, and Communications (C’) “ 287

mosphere and the higher data rates of high frequencies.

MF, which has short range, would be the

only means in the present baseline system

design by which the shelters could communicate with the ALCC to report their status.

Transmission would be through the buried MF

dipole antenna at each shelter. Taking into account soil propagation losses, the effective

radiated power from each shelter would be

only about 2 watts. The low power of the transmitter at each shelter would be multiplied by

the “simulcast” technique where each surviving shelter that contained an MX rnissile would

transmit its status via MF. Other surviving shelters receiving this message would repeat the

transmission simultaneously with rebroadcasts

by the original shelter. In this way, after many

repetitions, all of the surviving shelters would

be transmitting, in sequence, the status

message of each individual shelter, with a total

effective transmitting power of all the shelters

taken together.

Since only the shelters containing MX missiles would be transmitting in this period, these

emissions might reveal the locations of the surviving missiles if the Soviets could detect

them. However, the short range of groundwave MF would preclude direction-finding by

remote ground stations or ships, and ionospheric absorption and refraction would prevent satellites from detecting and locating the

emissions. Thus, this hypothetical threat to

PLU may be impossible for the Soviets to capitalize on. This security from detection is one of

the reasons why MF communication was

chosen.

The simulcast would also be used to enable

the surviving missiles to redistribute targets

among themselves in order to maintain coverage of the highest priority targets. The missiles

would be numbered I through 200, and for

each SIOP option there would be 200 target

sets, numbered 1 through 200 in priority order.

Before the attack, missile #l would have target

set #l, missile #2 target set #2, and so on. After

the attack, missile #200 would listen on the MF

simulcast for a status message from missile ##1.

If missile #I did not report or reported that it

was unable to fire, missile #200 (if it survived)

would assume target set M. If missile #2 had

not survived, its target set would be assumed

by missile #199 (if it survived), and so on.

Transattack two-way communications between the ALCC and the missile force would

rely exclusively upon the single MF I ink, Since

MF is short-range, the ALCC would have to approach within 50 to 100 miles of the missile

field in order to receive the MF simulcast and

assess the status of the force. There could be

concern for the effects upon the ALCC of dust

and radiation lofted into the atmosphere by

the attack.

This

vialing

and/or

shown

WOUI d

situation could be improved by proHF transmitters (as well as receivers)

SATCOM terminals at the shelters, as

in figure 125. A UHF SATCOM terminal

cost about $100,000, so SATCOM at

each shelter would cost about $500 miIIion.

Postattack

The postattack period, as defined for the

purpose of this discussion, would begin when

the airborne command posts (ALCC and

NEACP) were forced to land, either to refuel or

for extended grounded operations. The baseline C3 system for this period is shown in figure

126. HF and MF skywave communications

could be disrupted for hours or days after attack. The ground-wave communications would

in any case be short range. The ALCC would

have to be within 50 to 100 miles of the shelters or it would be out of MF range. The Soviets

would not necessarily spare airfields this close

to the deployment area. There would therefore

be a need for long-haul two-way communications from the grounded aircraft to the shelters

in the postattack period. This communication

would be needed especially if the ALCC were

inoperable, and the grounded NEACP had to

communicate with the MX force over thousands of miles.

Means to provide these two-way long-haul

communications that are not part of the present baseline design are shown in figure 127.
288 ● MX Missile Basing

Figure 125.—Possible Additions to Baseline MPS Communications System

(transattack)

SOURCE: Office of Technology Assessment,

Figure 126.–Communications System for Baseline MPS System (postattack)

Shelter

SOURCE: Office of Technology Assessment.
Ch. 10—Command, Contro/, and Communications (C’) ● 289

Figure 127.—Possible Additions to Baseline MPS Communications System

(postattack)

(Reconstitutable

UHF SATCOM)

antenna

HF, MF ground network

SOURCE. Off Ice of Technology Assessment.

They include adaptive HF, ground-based HF or

MF relays proliferated across the United

States, satellite communications, and erectable LF antennas.

MPS Basing with LoADS ABM System

The two principal C3 functions required if

LoADS were added to MPS basing would be:

1 ) tactical warning of Soviet attack so that the

LoADS defense units (DUS) could break out of

their shelters and prepare to defend; and 2)

communications to transmit a breakout order

and authorization to activate the nucleararmed interceptors (“nuclear release”).

If the design goal providing for awakening

dormant electrical equipment in the DU and

breaking the radar and interceptor cannister through the shelter roof within a very short

period of time could be achieved, warning of

Soviet attack would not be required until late

in the flight of the Soviet ICBM reentry vehicles (RVS). Means to provide such late warning

(within 15 minutes of impact) could include

rocket-launched sensor probes, sensor aircraft,

and ground-based radars, in addition to satellites. Such warning sensors are discussed extensively in chapter 4. Radars similar to the

LoADS radars themselves could be positioned

at the northern edges of the deployment area.

The sensors could provide attack assessment if

such information were required to attempt to

limit degradation of defense effectiveness in

the face of a potential Soviet Shoot-LookShoot capability (see ch, 3). Without adequate

warning for breakout, the LoADS defense

would clearly be useless. If breakout occurred

in peacetime as a result of error, the shelters containing the LoADS DUS would be

destroyed.

83-477 0 - 81 - 20
290 ● MX Missile Basing

Though it might be feasible physically to

activate the defense in a short time, the procedures whereby commanders assessed the warning information and ordered breakout and nuclear release could in practice lengthen the reponse time considerably. In the present LoADS

command concept, breakout and nuclear

release are effected by two distinct commands. The communications needed to support timely activation of the defense would depend on who was authorized to order nuclear

release. Offensive nuclear release must be

ordered by NCA. Whether authority for defensive nuclear release could be delegated to military commanders is unclear.

At the time the breakout and release orders

were given, detonations of Soviet SLBM RVS

could already have occurred in the deployment area and at other centers of the National

Military Command System. MF injection from

the ALCC might therefore be the only means to

transmit the defense commands. If the ALCC

operating area were expanded by using longer

range communications (H F or VLF/LF) between

the ALCC and the shelters, the lower data rates

could lengthen the time it would take to transmit commands to the defense.

At present, uncertainties in the LoADS system architecture and unresolved operational

procedures do not permit judgment on the feasibility of supporting the defense’s warning

and breakout needs.

If a LoADS defense were added to a verticalshelter MPS system, the radar and interceptor

cannister would have to be emplaced in separate shelters. In this case it would probably be

necessary to deploy a separate communications network to support the rapid transfer of

data from the radar to the interceptors in an

engagement.

Launch Under Attack

Warning and communications systems to

support reliance upon launch under attack are

discussed extensively in chapter 4. Since these

systems would be the only “basing mode” to

speak of, considerable time, effort, and money

would presumably be spent assuring their reliability in the face of determined Soviet efforts

at disruption. As discussed in chapter 4, it

wouId be technically feasible to deploy a wide

variety of warning sensors and communications links to airborne command posts that,

taken together, would be exceedingly difficult

for the Soviets to disrupt. Such disruption

could furthermore be made time-consuming

and provocative.

What cannot be determined on the basis of

technology alone is whether information provided by remote sensors would be adequate to

support a decision of such weight as the

launch of U.S. offensive weapons, whether

procedures could be devised to guarantee

timely decisions by NCA, and whether (given

the complex interaction of human beings and

machines operating against a short timeline) a

bound could be set and enforced upon the

probability of error resulting in catastrophe.

Small Submarines

Since seawater absorbs radio waves of all

but the lowest frequencies of the radio spectrum, completely submerged submarines are

confined to low data-rate receive-only LF, VLF,

and ELF communications. Two-way communications and high data rates require putting

either a mast antenna or a trailing buoy antenna above the surface. While the buoy or mast

antenna itself poses essentially no threat to

submarine covertness, broadcasts at moderate

frequencies could reveal the locations of the

submarines. E H F communications to survivable deep-space satellites such as have been

proposed for a wide variety of military communications missions would permit high datarate communications from submarines to commanders with essentially no risk to submarine

covertness. Present U.S. fleet ballistic missile

submarines use a variety of classified means

for report-back.

This section describes a technically feasible

C

3 system to support small submarine basing

of MX. The system described differs somewhat

from the C’ system that supports present sub-
Ch. 70—Command, Control, and Communications (C3

) ● 291

marine forces and intends to provide the small

submarine force with some of the attributes of

a land-based missile force.

Preattack

SYSTEM DESCRIPTION

The preattack C] system is shown

128.

The land-based VLF transmitters

in figure

exist at

present. The network provides worldwide coverage and would be more than adequate for

the small submarine deployment area. The

transmitters have high power, adequate antijam capability, and can transmit an EAM to

submerged submarines in an extremely short

time. There is also a worldwide LF network.

The EHF satellites do not exist at present,

but a similar satellite (LES 8/9) has been

deployed with great success. EHF frequencies

are chosen because jamming them is virtually

impossible, submarines can communicate with

virtualIy no chance of betraying their locations, data rates are high, and small (5 inch)

mast antennas can be used. Such satellites in

deep-space orbits could be made exceedingly

difficult for the Soviets to disrupt (see the

discussion of ASAT in the Technical Aspects of

Strategic C3 section).

PREATTACK FUNCTIONS

peacetime covert operations could be accomplished in the same way as with the present submarine force copying VLF. The VLF network would also permit transmission of an

EAM in an extremely short time. The SIOP

would contain a timing plan, keyed to a reference time in the EAM, to allow the missiles to

coordinate their time-on-target. Depending on

where it was in the deployment area, each

missile would calculate a launch time, reentry

angles, missile maneuvers, and bus deployment to provide the required time-on-target

coordination. Coverage and footprinting could

be arranged by advance operational planning.

Ad-hoc targeting instructions for limited

nuclear options could be assigned to 10 to 12

percent of the force that would be snorkeling

at any given time. These submarines could be

copying high data-rate SATCOM via their mast

antennas. If a larger portion of the force were

required for ad-hoc retargeting, the VLF netFigure 128.—Preattack C3 System for Small Submarines

SOURCE: Office of Technology Assessment
292 ● MX Missile Basing

work could direct more submarines to erect

their masts or deploy awash buoys to copy

other communications.

Report-back could be arranged, at no additional risk to the submarines, by having them

transmit status messages via EHF SATCOM

whenever they snorkeled. Classified means are

used today for submarine report-back.

Transattack

SYSTEM DESCRIPTION

The transattack period is defined for the purposes of this chapter as the period when

NEACP and TACAMO are airborne. This period

would normally be the first 12 to 14 hours after

attack plus additional periods if provision

were made for extended operations. The transattack CJ system is shown in figure 129.

The land-based VLF antennas are assumed

destroyed in the attack, though this might not

be true of the antennas on the soil of other nations. The EHF satellites are assumed intact.

There are at present several TACAMO aircraft in the Atlantic and a few in the Pacific.

More Pacific TACAMOS are expected to support Trident operations. These TACAMO aircraft will be EM P-hardened.

Both TACAMO and the E-4B NEACP would

be capable of transmitting an EAM directly to

submerged submarines from their VLF trailing

antennas <

TRANSATTACK FUNCTIONS

Prelaunch damage assessment and targeting

reoptimization would be unnecessary for the

small submarine force, since it would be expected to be almost completely survivable.

EAM transmission could occur via VLF from

TACAMO or NEACP. When the submarines

lost communications with the land-based VLF

transmitters, they would tune to TACAMO.

Ad-hoc retargeting would require high data

rates and two-way communications, so VLF

would not be appropriate. A short-coded message via VLF ordering certain submarines to

come to depth and copy targeting instructions

via E H F SATCOM would be a means to accomplish ad-hoc retargeting the transattack period.

Figure 129.-Transattack C3 System for Small Submarines

SOURCE Office of Technology Assessment
Ch. 10—Command, Contro/, and Communications (C3

) “ 293

Postattack

Two-way communications via EHF SATCOM

could be available in the postattack period,

and HF and UHF SATCOM could be reconstituted in this period as well. The postattack C3

system is shown in figure 130.

Air Mobile MX

Preattack

The principal preattack C3 requirements for

an air mobile fleet would concern receipt of

timely warning messages to support the fleet’s

high alert posture. A wide variety of reliable

warning sensors, available at some cost, is

discussed in chapters 4 and 6. The communications I inks from these sensors to commanders authorized to order dispersal of the

fleet and from commanders to the alert airbases would presumably be used before the

communications system had suffered extensive damage.

The responsiveness of an air mobile force to

a launch order wouId be limited to the time—

perhaps 10 minutes or so– it would take the

aircraft to take off and climb to launch

altitude.

Transattack and Postattack

The C3 system to support the complex force

management needs of the dispersed MX fleet

would require at least teletype data-rate communications between each missiIe-carrying aircraft and command aircraft. The aircraft

would be required to report their status, including remaining fuel supplies, and receive

launch instructions. Targeting reoptimization

would not be required if a substantial portion

of the fleet survived the initial attack. The airborne fleet could make use of a wide variety of

communications including UHF line-of-sight

(including the PACCS fleet), adaptive HF,

VLF/LF, and SATCOM, as shown in figure 131.

The communications system itself would be

low risk, the principal C3 problems being associated with the need to manage the dispersed

force, assess its status, and ready it for launch.

The problems of making provision for endurance beyond the few hours of unrefueled flight

time are discussed extensively in chapter 6. If

Figure 130.—Postattack C3 System for Small Submarines

SOURCE: Off Ice of Technology Assessment
294 ● MX Missile Basing

Figure 131 .—Transattack Air Mobile MX Communications System

PACCS

SOURCE: Office of Technology Assessment.

airfields survived for reconstitution, they

would have to be located, their status assessed

(including local fallout levels), and landing

aids provided in advance.

Last, providing for missile accuracy comparable to land-based MX would require communications from Global Positioning Satellites

(GPS) or a Ground Beacon System (GBS).

OVERVIEW OF RADIO COMMUNICATIONS

Radio Wave Propagation

This section discusses some of the characteristics of radio waves that are relevant to strategic communications systems.

Radio waves are electromagnetic disturbances that propagate with the speed of light

and, under certain conditions, can be bent, reflected, and absorbed within different regions

of the upper atmosphere. The propagation

characteristics of radio waves in the upper atmosphere differ markedly for waves of different frequencies. Propagation can also change

with time of day, time of year, and sunspot activity. In addition high-altitude nuclear explosions can dramatically alter the propagation

characteristics of radio waves within the atmosphere. This circumstance has obvious and

important implications for communications

systems that may have to function reliably in a

nuclear environment.

Radio communications bands are, by convention, referred to by different names. Since

the names of these bands are commonly used

in discussions of communications systems,

they are summarized in table 34.

The rate at which a radio wave is able to

transmit information is determined by its frequency (assuming there is no significant noise,

fading, or other fluctuation effects mixed in

the signal). This rate can be thought of as the

number of times per second (the unit of frequency is the Hertz; one Hertz is the same as

one cycle per second) the signal can be turned

“on” or “off” in order to create the sound of a

voice or to transmit information in other

forms. This “on-off” rate can never be greater

than the frequency of the wave since the frequency of the wave is in fact the number of

times per second that the wave itself is turned

“on and of f.” A rough rule of thumb is that a
Ch. 10—Cornmand, Contro/, and Communications (C’) ● 295

radio signal can carry information at about 10

percent the rate of its frequency. Thus, if lowfidelity voice communication requires the

transmission of a voice signal that has primary

frequency components in the 1,000 to 2,000

cycle per second range, then the radio wave

must have a frequency of at least 10,000 to

20,000 Hertz. This means that the lowest

usable frequencies for voice communications

lies in the upper end of the LF band. Highquality voice transmission would require the

transmission of voice components at frequencies of order 10,000 to 15,000 Hertz, thus requiring frequencies on the order of several

hundreds of kiloHertz. These frequencies lie in

the lower end of the MF band or broadcast

band, where commercial AM radio stations are

licensed to operate. For situations that require

particularly reliable signal reception and good

rejection of noise, much higher frequencies are

preferable, as is the case with high fidelity

music transmissions that are transmitted in the

VHF (FM radio) band. Still higher data rates

may be required for transmitting enough information to construct pictures rapidly in time,

as is the case in television broadcasting. Television information rate requirements dictate

radio frequencies in the VHF and UHF radio

bands.

Radio waves can be received betwee n

ground stations over several different physical

paths If the stations are close enough together

to have line-of-sight contact, they can receive

“direct-wave” transmissions (see fig. 132). It is

also possible to use different layers of the upper atmosphere to bend or reflect radio waves

back toward the surface of the Earth for overthe-horizon reception (or for over-the-horizon

radars). Signals received over such paths are

called skywaves. Radio waves can also be reflected from the surface of the Earth, to the

ionosphere, and back again toward the Earth.

This phenomenon, which occurs mostly at lower radio frequencies, can result in the radio

wave being “guided” along the Earth’s surface

for great distances. The radio waves are, in effect, trapped by the boundaries of the ionosphere and the Earth’s surface.

Figure 133 shows a graph of typical

distances over which communications can be

Figure 132.—Physical Paths of Radio Waves

SOURCE: Office of Technology Assessment

Figure 133.—Electromagnetic Transmission Ranges

at Different Frequencies

Nightime skywave

2,000 -

10-4 10-’ 1 10’ 10’ 10’ 105 1 0

Frequency in megaHertz

SOURCE. Office of Technology Assessment

achieved between ground stations using commonly available radio equipment. VLF signals

(designated by an arrow at 10 KHz on the

graph) can be reliably received at distances of

many thousands of miles because they are
296 ● MA Missile Basing

guided along the Earth’s surface by the boundaries on the ionosphere and the ground (fig.

134 shows the geometry of VLF over-thehorizon radio propagation). At higher frequencies encountered in the LF band, radio waves

begin to suffer attenuation at the greater

distances due to absorption. As a result of

these effects, LF reception tends to be of

shorter range than that of VLF waves. At still

higher frequencies, less and less of the radio

waves get redirected back to the Earth’s surface by the ionosphere and the range at which

radio transmissions can be received drops to

the line-of-sight distance. (For radio transmissions, line-of-sight distances are approximately

40 miles. This distance is somewhat larger than

visual Iine-of-sight distances. ]

Many communications applications require

high data rates in addition to long range and

high reliability. High data-rate communication

mandates the use of high radio frequencies.

Since high frequencies are either not reflected

or poorly reflected from the ionosphere, it is

necessary that the transmitter and receiver

have line of sight geometry if reliable communications are to be affected. One way of increasing the range of line-of-sight radio communications is to use airplanes.

Figure 135 illustrates schematically the geometry for line-of-sight communications beFigure 134.— Over-the. Horizon Radio Transmission

❑

Transmitte r Receiver

site site

SOURCE: Office of Technology Assessment

Figure 135.—Geometry of Aircraft Direct

Path Communications

SOURCE: Office of Technology Assessment.

tween aircraft. As an airborne relay, line-ofsight transmission between aircraft can be affected over distances of approximately 400

miles using the HF and UHF bands. The aircraft

can also communicate with ground installations over distances of approximately 200

miles at those same frequencies.

Another feature of aircraft communications

links is that they are constantly in motion and

are therefore difficult to target from great distances. For this reason, aircraft are particularly

useful as survivable command posts, launch

control centers, and communications relays.

For still greater distances and high data-rate

communications, satellites can be used as orbiting relays. The geometry of an orbiting

satellite relay is shown in figure 136. A particularly convenient orbit used for long-range,

high data-rate satellite communications is at a

distance of 22,300 miles from the Earth. Satellites in orbits that lie in the plane of the

Equator at that distance will always remain

over the same point on the Earth’s surface. For

this reason, many communications satellites

are put in such “geosynchronous” orbits.

Disruption of Radio Communications

Due to Nuclear Detonations

Electromagnetic Pulse

When a nuclear detonation occurs, a large

number of gamma rays is emmitted by nuclei

in fission and fusion reactions, resulting in an

initial “gamma flash” of extremely high intensity. If the nuclear weapon is detonated at an

altitude above the sensible atmosphere, the

gamma rays from the weapon can induce extremely intense electromagnetic fields in the

layer of air between 15 and 25 miles altitude.
Ch. 10—Command, Control, and Communications (C3

) . 297

Figure 136.—Geometry of Satellite Communications

Satellite

SOURCE. Off Ice of Technology Assessment

These electromagnetic fields will then propagate towards the surface of the Earth.

Nuclear-explosion-generated electromagnetic phenomena of this type are known as

EMP effects. EMP fields are of great interest

since they are sufficiently intense to represent

a potential threat to the survivability of almost

al I electronic equipment.

Figure 137 shows the area over which an intense electric field of 25,000 volts per meter or

more would be generated by a nuclear explosion of several hundreds of kilotons yield at an

altitude of 190 miles. The area affected essentially covers the entire United States and parts

of Canada and Mexico.

The size of the area that could be affected

by EMP is primarily determined by the height

of burst and is only very weakly dependent on

the yield. For example, the size of the affected

area shown in figure 137 could be increased by

60 percent if the detonation height were increased to an altitude of 300 miles. Thus,

severe EMP effects are possible over very large

areas without the use of high-yield weapons.

Figure 137.-Electromagnetic Pulse Ground

Coverage for High-Altitude-Nuclear Explosion

Peak electric field

25,000 volts/meter or greater

Height of burst = 190 miles

SOURCE: Off Ice of Technology Assessment

The physical reason for the altitude dependence of EMP phenomena can be seen from

figure 138. The tangent to the Earth from the

burst point determines the maximum range at

which the gamma rays can induce intense electromagnetic fields. The gamma rays initially

generated by the exploding weapon deposit

their energy in a band of the atmosphere between 15 and 25 miles altitude. The electromagnetic field that reaches the surface of the

Earth is generated within this band of atmosphere. If the weapon is detonated at a

greater height, the tangent will occur at a

greater ground range from the surface zero

point, and the extent of the gamma ray-induced band will also be greater.

During the initial period of a nuclear attack,

intense electric fields from high-altitudenuclear detonations could cause severe damage to electronic equipment. PowerIines, radio

antennas, metal conduits, and other conducting surfaces would collect EMP energy like

antennas and destroy or disrupt the electrical

equipment to which they were connected.

Even equipment that had been carefully designed to survive the effects of EMP could be

temporarily disrupted for a period after a high-
298 ● MX Missile Basing

Figure 138.—Origin of Electromagnetic Pulse From High-Altitude-Nuclear Explosion

SOURCE: Office of Technology Assessment

altitude nuclear detonation (for instance EMPprotected computers could be disrupted by

loss of sections of memory or computation).

Ionospheric Disruption

Since the gamma rays from a high-altitude

nuclear detonation can change the electron

densities in very large regions of the ionosphere, the propagation characteristics of

radio waves may change dramatically. A result

of this change could be a “blackout” of radio

communications.

Figure 139 shows the skywave paths of radio

waves of different frequencies. The D layer of

the ionosphere is responsible for ref Iecting VLF

and LF radio signals. Nuclear explosions in or

above the D layer would change ionization

levels in the D layer. The effect of this change

would be to lower the altitude at which VLF

and LF signals would be reflected from the

ionosphere. This effect could disrupt communications over long ranges, but it would be

unlikely that VLF and LF communications

would be blacked out by nuclear detonations.

MF radio propagation is normally limited to

groundwaves because the MF radio waves get

absorbed in the D layer before they can reach

the upper layers and be reflected back to the

Earth’s surface. At night, when the lack of

sunlight results in a drop in the ionization of

the D layer, MF radio may propagate to fairly

great distances (see the curve marked nighttime skywave transmission in fig. 133). For this

reason it is sometimes possible at night to pick

up AM broadcasts from remote transmitters.

Nuclear explosions in or above the D layer

could blackout MF skywave communications

for hours near the point of detonation.

The HF band is used extensively for longrange communications. If conditions in the

ionosphere are such that H F waves are not absorbed, HF waves will be bent back to Earth

when they reach the E and F layers of the ionosphere (see fig. 139). HF is particularly useful

for long-range communications because its f requency is high enough that large amounts of

information can be transmitted and yet it is

low enough that the ionosphere will bend it

back to the surface of the Earth.

Nuclear detonations in or above the D layer

could change ionization levels sufficiently to

cause absorption of HF waves in the D layer.

The changed ionization levels could also lower

the altitude at which HF waves were reflected

from the ionosphere (see fig. 140). This change

could result in severely degraded HF communications for periods of minutes to hours.

A nuclear burst at an altitude of approximately zoo mi Ies wou Id be expected to disrupt

HF communications over the same area in

which severe EMP would be experienced. The

blackout from such a detonation could last for

hours.
Ch. 10—Command, Control, and Communications (C3) ● 299

I n bands above H F, most radio transmissions satellites were not attacked, communications

would suffer varying degrees of degradation at these frequencies would probably not suffer

through the ionosphere. However, provided severe degradation.

Figure 139.—Atmospheric Radio Propagation at Different Frequencies

... -n 1

I .[ ——. d.. -----*--*-——

u) 240P

a>

-&..-”-–

------ OD.-

- - -J\=-

. -. .- -. -. . . . .

200 400 600 800 1000 1200

Approximate ground range in miles

SOURCE Off Ice of Technology Assessment

Figure 140.— Radio Propagation Paths Before and After High-Altitude-Nuclear Explosion

Explosion induced Skywave

before ionospheric absorption nvnlncinn

Explosion induced 7 ‘,’

ionospheric reflection ~,z _

/

/4

N ‘ 4’

/

\

\

\

\

explosion

\

.

SOURCE Off Ice of Technology Assessment
Chapter 11

DIVERSITY OF U.S. STRATEGIC

FORCES
Chapter ll.— DIVERSITY OF U.S. STRATEGIC FORCES

Page

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ........303

Diversity and Vulnerability . . . . . . . . . . . . . . . . . . . . . . . . . . ...............304

Diversity and Weapon System Capabilities . . . . . . . . . . . . . . . . . . . .........305

Diversity and Deterrence. . . . . . . . . . . . . . . . . . . . . .................307
Chapter 11

DIVERSITY OF U.S. STRATEGIC FORCES

OVERVIEW

Among the many considerations that arise in

the selection of a basing mode for the MX missile is the perceived need to maintain diverse

U.S. strategic offensive forces. For the past 20

years, the United States has deployed a

“Triad” of strategic offensive forces— intercontinental ballistic missiles (I CBMS), submarine launched ballistic missiles (S LBMS),

and manned bombers—with each “leg” of

roughly equal importance. While the development of these strategic offensive forces

did not occur as a result of a conscious policy

for the procurement and use of strategic nuclear weapons, the diverse operational characteristics of U.S. strategic forces described

briefly below have stimulated the formulation

of American nuclear strategies and tactics that

seek to optimize the differing capabilities and

vulnerabilities of each leg of the Triad.

The following discussion assumes that no

matter what basing mode is selected for the

MX missile, the United States will also deploy

future strategic offensive forces composed of

Minuteman ICBMS, manned bombers, and

SLBMS on both Poseidon and Trident fleet ballistic missile submarines (SSBNS). For purposes

of OTA’S analysis, the MX missile is regarded

as an additional strategic nuclear weapons

delivery vehicle, rather than a substitute for

any existing U.S. strategic offensive nuclear

weapon. This assumption is consistent with existing or proposed Defense Department plans.

MX deployed on land in such modes as

multiple protective shelters (MPS), defended

MPS, defended silos, and in silos relying on

launch under attack would continue to provide the United States with hedges against

changes in the technological environment of

strategic forces. Any of these modes would

limit the effects of failures of American

technology encountered in the modernization

of the bomber and SLBM legs of the existing

Triad. These land-based MX basing modes

would continue to provide a hedge against

Soviet defenses, and would retain the present

characteristics of U.S. strategic offensive

forces that make it impossible for the Soviets

to pIan and execute a preemptive attack

against them with high confidence. The landbased MX basing modes would also retain

those attributes of strategic offensive forces

commonly thought to be the strong points of

existing ICBM forces.

Small submarine basing for the MX missile

would guard against some changes in the technological environment but not against others.

If the Soviet Union were to suddenly develop

and deploy an unexpected antisubmarine warfare capability, it might be effective against

Poseidon and Trident submarines as well as

small submarines carrying MX missiles; there is

also a risk that problems with other U.S. submarine construction programs might apply to,

or be exacerbated by, small submarine construction. Small submarines could acquire

military capabilities quite comparable to landbased MX deployment options. While landbased systems would be somewhat more accurate, OTA’S analyses do not clearly indicate

that the differences in accuracy would have

militarily significant practical implications.

There is a controversy over whether increasing the importance of sea-based as opposed to

land-based strategic forces would strengthen

or weaken deterrence.

Air mobile MX would share a common failure mode with the bomber force, but it would

not be targetable by Soviet ICBMS.

303
304 ● MX Missile Basing

DIVERSITY AND VULNERABILITY

Maintaining three completely different

types of strategic weapons delivery systems

over the past 20 years has provided the United

States with an insurance policy of sorts against

sudden and unforeseen technological developments. Diversity complicates Soviet efforts to

plan and execute a preemptive attack on

U.S. strategic forces with high confidence of

success.

Diverse U.S. strategic forces complicate

Soviet use of air defense, antiballistic missile

defense or antisubmarine warfare to prevent

destruction of their homeland in the event of

an attack by the United States. Diversity in

U.S. strategic forces necessitates the division

of Soviet offensive and defensive capabilities

among several distinct missions, thereby

diluting the resources that can be applied to

any one mission. The possibility of a sudden

and unanticipated technological Soviet development rendering any leg of the U.S. Triad

of strategic offensive forces is therefore reduced. Even if the Soviets developed an ability

to defend themselves against one leg of the

U.S. Triad, other legs could still carry out their

strategic missions.

Hence, one criterion that might be used in

comparing and contrasting various MX basing

modes is the degree to which each basing

mode would provide a hedge against vulnerability as a result of the technological change.

MX deployed in an MPS basing mode with or

without a low altitude defense system satisfies

this criterion, assuming that preservation of

location uncertainty (PLU) is maintained and

the MX/MPS is deployed on such a large scale

that the Soviets lack the number of reentry

vehicles (RVS) necessary to confidently attack

each MPS. Under these conditions, MX/MPS

would provide a hedge against technical problems that might be experienced during the

modernization of the manned aircraft and submarine legs of the Triad. The proliferation of

targets in the United States would make it sigWllliam J Perry, The F/sea/ Year 1981 Department of Defense

Program for Research, Development, and Acquisition (Washington, D C Department of Defense, 1980), p VI-1

nificantly more difficult for the Soviets to plan

and execute a preemptive attack against U.S.

strategic offensive forces. Timing and coordinating an attack against 4,600 MX shelters,

approximately 1,000 ICBM silos, bomber

bases, and the submarine force with high confidence of success would be a virtually impossible task.

MX/MPS might share a vulnerability to

Soviet ABM systems with other U.S. ICBMS or

SLBMS. However, the deployment of a large

MX/MPS system would stress Soviet defense resources in at least two different ways. First, the

Soviets would have to invest heavily in the

fractionation of their own RVS in order to acquire the number needed to destroy each

shelter with high confidence. Second, the

Soviets would have to invest in remote sensing,

clandestine sensors, and espionage if they

were to attempt to compromise PLU. The magnitude of these investments might make it difficult for the Soviets to pursue other strategic

programs with the same vigor and commitment of resources possible in the absence of

MX/MPS.

Deployment of MX missiles on small submarines provides a hedge against some kinds

of technological change. If a sudden and unanticipated technological development in the

field of antisubmarine warfare were to occur,

and if this development were to simultaneously threaten the Poseidon/Trident force as well

as the small submarine/MX force, considerable

diversity in U.S. strategic forces would be lost.

However, the small submarine basing mode examined by OTA would add considerable diversity to the U.S. strategic missile submarine

force. Since the nature of a sudden and unforeseen hypothetical breakthrough in Soviet antisubmarine warfare capabilities cannot be

predicted, it is impossible to judge the extent

to which diverse submarine types would

complicate or frustrate Soviet antisubmarine

warfare.

Moreover, deployment of MX missiles on

small submarines might not provide an adequate hedge against problems encountered in
Ch. n-Diversity of U.S. Strategic Forces “ 305

future U.S. submarine construction programs.

Present submarine construction facilities in

the United States are backlogged and plagued

by management problems. ’ If these problems

cannot be solved, small submarine deployment of MX missiles might not be an acceptable hedge against technical problems or delays in the deployment of Trident submarines

in the late 1980’s. The importation of modern,

proven diesel-electric submarine technology

from our North Atlantic Treaty Organization

(NATO) allies might provide a hedge against

continued problems in U.S. submarine construction programs.

Air mobile MX could be subjected to attack

on the ground just as the manned bomber

“’Statement of Adm Earl Fowler,” U S Congress, House Committee on Armed Services, Mar 12, 1981

force might be. In the absence of adequate

warning, both the bomber and air mobile MX

force could be destroyed. Air mobile MX

would hedge to some degree against improvements in Soviet air defenses that might jeopardize the effectiveness of air-launched cruise

missiles or a new penetrating bomber. It would

stress the ability of the Soviet Union to deploy

a large number of SLBMS close to the continental United States, a capability they do not

have today. It would not be targetable by

ICBMS.

Deployment of MX in silos and reliance on a

doctrine of launch under attack (LUA) completely fails to meet this criterion. MX/LUA

would share a common mode of failure with

the present Minuteman force that is thought to

be vulnerable to a Soviet preemptive attack

should there be a failure in warning or communications systems.

DIVERSITY AND WEAPONS SYSTEM CAPABILITIES

Present U.S. strategic doctrine emphasizes

the continuin g need for strategic offensive

forces that contribute to the deterrence of war

by virtue of their diverse military capabilities.

As Gen. David Jones, Chairman of the Joint

Chiefs of Staff noted in his report to the Congress for fiscal year 1982:

The primary purpose of U.S. strategic

nuclear forces is deterrence. To insure deterrence, these forces must be capable of executing national strategy under all conditions — no matter what the challenge, no

matter what tactics an opposing force may

choose. While a force composed of a single

delivery system could be optimum in certain

situations, the United States faces an international environment of diverse threats to national security. To deal effectively with this

wide range of strategic uncertainties, U.S.

strategic nuclear forces are structured around

an array of independent capabilities which can

confront any level of nuclear threat. 3

‘Cen David Jones, United States M//ltary Posture for Fiscal

Year 1982 (Washington, D C Department of Defense, 1981,

P 69

There is a wide range of military capabilities

believed to be needed for effective deterrence.

The ICBM leg of the Triad has been considered

superior to other legs of the Triad in several of

these military capabilities in the past. 4 These

military capabilities include the following:

●

●

●

●

●

accurate delivery of nuclear weapons (accuracy);

the ability to carefully control the time at

which a nuclear weapon arrives on its target (time-on-target control);

the ability to change targets assigned to

specific strategic nuclear weapon delivery

vehicles rapidly (rapid retargeting);

the ability of strategic forces to respond

quickly to attack orders (rapid response);

and

the ability to use a small number of strategic nuclear weapon delivery systems in a

flexible, limited manner (flexible use).

“Wllllam ) Perry, The f/sea/ Year /982 Department of Defense

Program for Research, Development, and Acquisition (Washington, D C Department of Defense, 1981, p Vi-l

83-477 0 - 81 - 21
306 ● MX Missile Basing

Accuracy is necessary to attack targets that

have been especially designed to withstand the

effects of nuclear weapons. Such targets might

include missile silos, communications facilities, specialized industrial facilities, and

hardened military facilities.

Time-on-target control is required to prevent

the earliest arriving nuclear weapons from destroying subsequent weapons in a multiple

weapon attack against a specific target. Timeon-target control may also be required in certain attack tactics in which the destructive effects of nuclear weapons are compounded

through use of multiple, closely spaced weapons against adjacent targets.

Retargeting of nuclear weapon delivery systems is desired in those cases where the President chooses an attack option from a menu of

preplanned attack options or alternatively

decides to attack a specific target that might

not be included in a particular attack option.

The ability to retarget a strategic nuclear

weapon delivery vehicle may also be required

in the event that some portion of the force is

destroyed and a retaliatory attack against important targets is ordered. Retargeting of surviving forces would be necessary to ensure

that high-priority targets would be attacked by

surviving forces.

Rapid retargeting is desired to give the President more options as new information is provided about the scope, magnitude, and apparent political objectives of an attack, or alternatively, to permit maximum flexibility in

the use of a force as it suffers attrition during

the course of an attack against it.

Rapid response to launch orders, referred to

as Emergency Action Messages, may be desired in order to take advantage of current

intelligence about the disposition of highvalue targets. Rapid response may also be

desired in the event that an attack against U.S.

forces is detected, thereby permitting the

launch of forces prior to their destruction.

Flexibility for limited attacks may be desired

so that political decision makers can attempt

to control the pace of escalation, trying to

limit the scope and magnitude of a nuclear war

to a level less than all-out or cataclysmic war.

Comparison of various MX basing modes

against these desired weapon system capabilities leads to the following observations.

MX deployed in an MPS mode with or without defense, in defended silos, or in silos relying on launch under attack would retain and

increase the military capabilities of the presently deployed ICBM leg of the Triad of U.S.

strategic offensive forces in terms of accuracy,

time-on-target control, rapid retargeting, rapid

response, and fIexibility for Iimited attack.

Small submarine-based MX would also expand the military capabilities of U.S. strategic

forces and could come quite close to the landbased MX basing options. While small submarine based MX would not have accuracy

quite as high as land-based MX, the difference

between the two could be so small as to be of

little practical consequence unless time-urgent

hardened targets of interest in the Soviet

Union were significantly more resistant to nuclear weapon effects than currently believed.

Time-on-target control for small submarine

based MX missiles could be comparable to

land-based missiles if the command and control system deployed to support small submarine-based MX permitted communication of

information needed to plan and execute such

attacks.

Rapid retargeting of small submarine-based

MX missiles could be comparable to landbased missiles. Retargeting of MX missiles deployed on small submarines to take attrition of

the small submarine force into account could

be more difficult than would retargeting of

land-based MX missiles; however, attrition of

small submarines appears far less likely than

attrition of the land-based MX force.

Small submarine-based MX missiles could

have response times comparable to land-based

MX if the communications systems supporting

them were properly designed and implemented. They would have very great flexibility

for use in limited nuclear exchanges. Unlike
Ch. 1 l—Diversity of U.S. Strategic Forces ● 307

larger Poseidon or Trident submarines, use of

an MX missile from a small submarine would

compromise the location of only a small fraction of the MX force on station at any given

time. Were one MX used, only three additional

MX missiles would be placed in jeopardy, as

compared with 15 Poseidon missiles or 23 Trident missiles in the event that one missile were

to be launched from the larger submarines. On

the other hand, the launch of one land-based

MX missile exposes no additional missiles to

possible immediate counterattack.

Air mobile and surface ship mobile MX

might not be quite as accurate as either landbased MX or small submarine-based MX misDIVERSITY AND

There is a wide range of views on the differences among various basing modes for the

MX missile in terms of continued maintenance

of strategic nuclear deterrence. The foIlowing

discussion summarizes the major points of

view.

One view holds that the United States must

retain a substantial portion of its most militariIy capable strategic forces on the continental

United States in order to effectively deter the

Soviet Union from initiating attacks on either

the United States or our allies. Russell E.

Dougherty, retired Commander in Chief of the

Strategic Air Command, summarized this view:

attacking the MX or any other land-based

ICBM located in the American heartland

forces an aggressor into the open. There can

be no ambiguity about an attack of the magnitude required to blunt even a small portion

of the U.S. ICBM force. Such an attack would

involve a very large number of ICBM warheads

with a flight time of about 30 minutes from

Soviet launch sites to U.S. targets. The attacker knows that the intended victim knows

with certainty and in some detail that a strike

has been launched. The attacker also is aware

that the victim has enough time to react to this

unambiguous act, and probably will. 5

‘Ru$sell E Dougherty, “The MX Ml$slle system – Keystone of

a Moclern Strategic Nuclear Force, ” A E / Foreign POIICY and Defen$e Re~ww, VOI 2, No 6, December 1980, p 7

siles. In addition, the need for aircraft carrying

MX missiles to take off and reach altitude to

drop missiles or surface ship carrying MX missiles to deploy to areas within range of landbased missile navigation aids would substantially reduce their ability to exercise timeon-target control and responsiveness. Furthermore, these operational requirements might

provide the Soviets with strategic warning of a

pending American attack.

Surface ship mobile would provide considerably less flexibility for limited use, given

that the use of one MX missile would compromise the location of large number of unused missiles carried aboard the surface ship.

DETERRENCE

Hence, deployment of the MX missile on land

drives up the threshold of attacks on the

United States, risking perhaps millions of

American civilian casualties, and, at least in

this view, assuring American retaliation. Deployment of air mobile MX would have similar

consequences were the Soviets to attempt to

attack this mode.

Another view holds that deployment of the

MX on the continental United States is politically important in the context of broader U.S.

efforts to win support for NATO theater nuclear forces modernization and promotion of

meaningful negotiations for Mutual and Balanced Force Reductions in Europe.

Adherents to these views tend, therefore, to

look with disfavor on the deployment of MX

missiles on either small submarines or surface

ships arguing that retention of the current

balance of capability among land-, sea-, and

air-based legs of the Triad is essential to the

maintenance of deterrence.

Others believe that the United States need

not create additional targets on the continental United States with the selection of a basing

mode for the MX missile. Retention of Minuteman ICBMS, bomber bases, submarine bases,

and the addition of shore support facilities for

either small submarine basing of MX missiles
308 ● MX Missile Basing

or surface ship mobile MX would still force the of radioactive fallout from an attack on MX/

Soviets to expend a sufficiently large fraction MPS, MX/defended MPS, air mobile MX, or

of its strategic forces to make clear its intent. silo-based MX. As a result deterrence could be

strengthened because the United States would

Deployment of MX missiles at sea, it is be better able to exercise escalation control

argued, reduces the amount of damage that with less of its population at risk as a result of

might be done to the United States as a result the MX basing at sea.
Chapter 12

ARMS CONTROL CONSIDERATIONS

AND MX BASING OPTIONS
Chapter 12.—ARMS CONTROL CONSIDERATIONS AND

MX BASING OPTIONS

Page

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .311

Basing Modes Inconsistent With Arms Control Agreements in Force . .......312

ABMTreaty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .312

OuterSpaceTreaty . . . . . . . . . . . . . . . . . . . . . . . 312

SeabedTreaty . . . . . . . . . . . . . . . . . . . . . . . . . . . . 312

OtherArms Control Agreements in Force Affecting MX Basing Decisions .. ...313

Limited NuclearTest Ban Treaty . . . . . . . . . . . 313

SALT I Agreements. . . . . . . . . . . . . 1 1 3

lmpactofSALTllonMX Basing . . . . . . . . . . . . . . . . 315

Other PendingArmsControl AgreementsAffectingMX Basing . 31 8

Future ArmsControl Negotiations . . . . . . . . . . . . .,319

ArmsControl and Stability . . . . )22
Chapter 12

ARMS CONTROL CONSIDERATIONS

AND MX BASING OPTIONS

OVERVIEW

This chapter discusses several ways in which

arms control considerations bear on the choice

of a basing mode for the MX missile. These

include the impact of arms control agreements

in force, the impact of agreements signed but

not yet ratified, and the possible impact of

various MX basing modes on future arms control negotiations. *

The 1972 ABM Limitation Treaty would prohibit the deployment of MX missiles in any

mode defended by an antiballistic missile

(ABM) system unless such deployments occurred within the Grand Forks, N. Dak.,

Minuteman field. The Treaty would also prohibit the deployment of ABM systems that

were not of a type explicitly permitted by Article I II.

The Seabed Arms Control Treaty would

prohibit deployment of MX missiles in fixed

shelters on the seabed floor or on any seabedmobile platform. The Outer Space Treaty

presently in force and the proposed SALT II

Treaty would prohibit deployment of MX missiles in any mode which launched nuclear

weapons into Earth orbit. None of these basing

modes appears attractive at this time.

Other arms control agreements either in

force or still awaiting ratification would permit

most MX basing modes. The proposed SALT II

Treaty would prohibit deployment of surface

ship mobile based MX as well as inland waterway variants of surface ships, submarines, or

deployment on the bottom of lakes, rivers,

canals, or other inland waterways. The SALT I

‘This dl~cusslon IS restricted to an assessment of the arms control Impllcat}ons of basing mode options only For a detailed

analysts of the arms control Impllcatlons of the MX mlsslle Itself,

see “ ICBM Programs, ” In U S Congress, House Committee on

Foreign Affairs and Senate Committee on Foreign Relatlons,

FIJca/ Year /982 Amr$ Control Impact Statements (Washington,

D C U S Government Prlntlng Off Ice, 1981), pp 26-71, passlm

Treaty would not prohibit other basing modes

assessed in this study if deployments could be

made in a manner that would permit verification, through use of national technical means,

of U.S. compliance with the terms of the Treaty were it in effect.

Minuteman III rebasing in a multiple protective shelter (MPS) mode could be undertaken if the SALT II Treaty limits were still in

effect after 1985; however, the Iimits on the

total number of MlRVed ballistic missiles

would, if still in effect, prevent the United

States from deploying an economical mix of

missiles and shelters for Minuteman IIl/MPS to

keep pace with plausible Soviet theats unless

the number of U.S. submarine-launched

ballistic missiles (SLBMS) armed with multiple

independently targetable reentry vehicles

(Ml RVS) deployed were decreased.

The 1963 Limited Test Ban Treaty that is

presently in force, and the 1974 Threshold

Nuclear Test Ban and the 1976 Peaceful Nuclear Explosions Treaties that are signed but

still awaiting U.S. ratification, contain provisions that limit the ability of the United States

and the Soviet Union to conduct nuclear

weapons explosions useful in generating empirical data that would be helpful in designing

both basing modes and attack strategies

against them.

Most basing modes for the MX missile pose

relatively few future arms control negotiating

problems. MPS basing for MX and Minuteman

III raises serious negotiating problems because

a very high premium is placed on limiting the

number of RVS the Soviets can deploy on

intercontinental balIistic missiles (ICBMS).

MPS also would compel arms control negotiators to specify procedures for verification at

a level of detail not successfully negotiated in

earl ier arms control negotiations.

311
312 ● MX Missile Basing

BASING MODES INCONSISTENT WITH

ARMS CONTROL AGREEMENTS IN FORCE

Most basing modes considered for the MX

missile are not prohibited by arms control

agreements currently in force. However, three

treaties contain specific provisions that would

be contravened by some basing modes for the

MX missile.

ABM Treaty

As noted in chapter 3 the 1972 ABM Limitation Treaty prohibits widespread ABM deployment to defend MX missiles in any basing

mode. In addition, it also constrains deployment of a limited ABM system in numbers of

radars, ABM launchers, and ABM interceptor

missiles and restricts such deployment to the

vicinity of the Grand Forks, N. Dak., Air Force

Base.

Outer Space Treaty

Article IV of the 1967 Outer Space Treaty

provides:

States Parties to the Treaty undertake not to

place in orbit around the Earth any objects

carrying nuclear weapons or any other kinds of

weapons of mass destruction, install such

weapons on celestial bodies, or station such

weapons in outer space in any manner.

This prohibition would be a legal barrier to any

deployment of MX missiles that were used to

launch nuclear weapons into Earth orbit under

any circumstances. *

There are major technical obstacles to the

deployment of militarily effective nuclear

weapons aboard Earth-orbiting platforms.

These obstacles include accurate delivery of a

nuclear weapon to a fixed point on the Earth

and maintenance of adequate command and

control over an orbiting platform during a nu-

“’Outer Space Treaty, ” in U.S Arms Control and Disarmament Agency, Arms Control and Disarmament Agreements, 1980

Edition (Washington, D C U S. Government Printing Office,

1980), p 52 Cited below as Arms Contro/ Agreements.

*A similar obligation IS found in the proposed SALT I I Treaty.

clear conflict. Launching nuclear weapons into

orbit cannot now be regarded as a technically

attractive basing mode for the MX missile.

Seabed Treaty

A third arms control treaty containing provisions that would rule out a basing mode that

is technically feasible is the 1971 Seabed Arms

Control Treaty. Article 1 provides:

1. The States Parties to this Treaty

undertake not to emplant or emplace on the

seabed and the ocean floor and in the subsoil

thereof beyond the outer limit of a seabed

zone, as defined in Article 11, any nuclear

weapons or any other types of weapons of

mass destruction as well as structures,

launching installations or any other facilities

designed for storing, testing or using such

weapons. 2

This provision would prohibit the deployment

of MX missiles on various platforms that

crawled along the seabed floor, in silos dug

into the ocean floor, or in other fixed

structures attached to the ocean floor.

Mobile platforms that crawled along the

seabed floor would be detectable with various

underwater remote-sensing equipment. Like

other large land-mobile systems, seabed crawling platforms would not be fast enough to

escape a determined effort to barrage attack

their last known positions. While the ocean

would provide some degree of protection from

some nuclear weapon effects, seabed crawlers

carrying MX missiles would nevertheless be

vulnerable to nuclear weapons attack. Fixed

shelters or silos dug into the seabed floor

wouId have similar vulnerabiIities.

Moreover, there would be many complicated, expensive, and technically challenging

operational problems to be met before such a

system could be deemed a technically feasible

“’Seabed Arms Control Treaty, ” In Arm\ Contro/ A~reempnt$

p 102
Ch. 12—Arms Control Considerations and MX Basing Options ● 313

basing mode for the MX missile. Hence, it does Treaty prohibits the deployment of the MX

not appear that the Seabed Arms Control missile in any attractive basing mode.

OTHER ARMS CONTROL AGREEMENTS IN FORCE

AFFECTING MX BASING DECISIONS

Limited Nuclear Test Ban Treaty

The 1962 Limited Nuclear Test Ban Treaty

prohibits the detonation of nuclear explosive

devices in the atmosphere, under water, and in

outerspace. 3

These limitations on nuclear

weapons testing prevent the United States or

the Soviet Union from conducting nuclear

explosions that could generate empirical data

about nuclear weapons effects that might be

needed to resolve major technical uncertainties in areas such as the following: the

hardness of vertical and horizontal protective

shelters; nuclear weapon effects on aircraft,

surface ships, and submarines, or other vehicles used to carry MX missiles; the effects of

nearby nuclear detonations on ABM systems

and components; nuclear weapons effects on

communications during and immediately after

an attack; the effects of multiple nuclear

weapon detonations in close proximity to a

small number of protective shelters; and the

development of strategies and tactics to

attack or to defeat an attack on MX/MP S

deployments. However, the amount of technical risk for each basing mode introduced by

the lack of atmospheric nuclear weapons test

data is relatively minor in comparison with

technical risk created by other factors.

SALT I Agreements

The SALT I Agreements of 1972 contain several provisions that might affect MX basing

decisions. The SALT I Agreements consist of

two separate agreements: The 1972 ABM

Limitation Treaty previously discussed, and

the Interim Agreement on Strategic Offensive

Forces. ’ The Interim Agreement on Strategic

‘“L Imited Test Ban Treaty, ” art I In Ibid , p 42

4 “ I nterlm Agrtwrnent on Strategic Of fen\lve Arms, ” In Iblcj ,

pp 15015 7

Offensive Forces, however, was an Executive

Agreement and was affirmatively endorsed by

the House of Representatives and the Senate

pursuant to section 33 of the Arms Control and

Disarmament Act of 1961. It set limits on the

numbers of ICBM and SLBM launchers that the

United States and the Soviet Union could deploy for the period May 1972 through October

1977, When it expired, both the U.S. and the

Soviet Governments indicated that pending

the completion of negotiations for a SALT II

Treaty, they would continue to abide by the

terms of the Interim Agreement unless or until

the other party to that agreement undertook

an action that was inconsistent with the terms

of that agreement. 5b

Article I of the Interim Agreement prohibits

the construction of additional fixed land-based

ICBM launchers after July 1, 1972.7 Hence if

the Interim Agreement were still de facto in

effect when the MX was to be deployed, MX

basing in silos would be limited to modified

Minuteman silos rather than new ones.

5“Statement by Secretary of State Vance United States Intent

Regarding the SALT I Interim Agreement, September 23, 1977, ”

In U S Arms Control and Disarmament Agency, Documents on

Disarmament, 1977 (Washington, D C U S Government Printing

Off Ice, 1979), pp 577-578

Secretary of State Vance Issued the following statement

I n order to m a Int aln the status quo w h I Ie SA I T I I negot I at Ions are

being completed, the United States de{ Iares lt~ Intent Ion not to take

any action Inconsistent with the provisions of the Interim Agreement

on certain measures with re~pect to the I Imltatlon of ~trateglc of fenSIVe arms which expire~ 0[ tober 3, 1977, and with the goals of these

ongoing negotlatlon~ provided the Soviet Un Ion exercises similar

restraint

“’Statement by the Soviet Union Intent Regarding the SALT

Interim Agreement, Sept 24, 1977, ” Ibid , p 578

I n ac( ordance with the reacflness expressed by both $Icfes to complete a new agreement Ilmltlng ~trateglc offensl~ e arms and In the interests of malntatnlng the status quo whl Ie the talks on the new

agreement are being cone Iuded, the Soviet Unton expresses Its lntentton to keep from anv a( tlons [compatible wtth the provisions of

the Interim agreement on some measures pertaining to the Ilmltat Ion

ot >trateglc offensive arms which expires on October 3, 1977, and

w It h the goa Is ot the ta Iks that are being conducted, provided that

the U nlted States of America show~ the same restraint

7“ Interim Agreement, ” In Arms Contro/ Agreements, p 150
314 ● MX Missile Basing

Modernization of SLBM platforms is specifically permitted under article IV of the Interim

Agreement, so deployment of both the Trident

submarine and small submarines armed with

MX missiles would be allowed were the terms

of the Interim Agreement still being observed

at the time MX deployment was made.8

During the final hours of the SALT I negotiations, Department of Defense (DOD) Representative Paul Nitze spoke for the U.S .

Government on the question of land-mobile

ICBMS. Nitze said:

In connection with the important subject of

land-mobile ICBM launchers, in the interest of

concluding the Interim Agreement the U.S.

Delegation now withdraws its proposal that

Article I or an agreed statement explicitly

prohibit the deployment of mobile land-based

ICBM launchers. I have been instructed to

inform you that while agreeing to defer the

question of limitation of operational landmobile ICBM launchers to the subsequent

negotiations on more complete I imitations on

strategic offensive arms, the U.S. would

consider the deployment of operational land

mobile ICBM launchers during the period of

the Interim Agreement as inconsistent with the

objectives of that Agreement.9

The purpose of this statement was to warn the

Soviet union that the united States would consider the deployment of the SS-16 in its mobile

mode to be legitimate grounds for terminating

the Interim Agreement. It was not intended to

preclude U.S. deployment of a mobile ICBM at

some future point in time if agreement on

measures to ensure adequate verification of a

SALT treaty limiting offensive forces could be

negotiated.

The Protocol to the Interim Agreement limits to 710 the number of SLBM launchers permitted for the United States. The Protocol further provided that both the United States and

the Soviet Union could exchange retiring

‘Ibid , p 151

“’Unitateral Statement [B]: Land-Mobile ICBM Launchers, ”

Ibid , p 156

ICBMS deployed prior to 1964 for new

SLBMs. ’O However, President Nixon informed

the Soviet Government that the United States

would not exercise its right under the provisions of Article 11 I of the Protocol to convert

older ICBMs into newer SLBM launchers.

The number of SLBM launchers deployed by

the United States would exceed 710 if deployment of MX missiles on small submarines

were to take place, the 31 SSBNS built in the

1960’s armed with Poseidon and Trident

missiles were retained in the fleet, and more

than nine Trident submarines were to be

deployed simultaneously. A judgment on the

strategic utility of continuing into the late

1980’s and 1990’s to adhere to the terms of the

1972 Interim Agreement on Strategic Offensive Forces would require considerable technical and political analysis as the number of

deployed MX missiles on small submarines, Trident submarines, and remaining Poseidon submarines approached the limit of the Interim

Agreement.

The second component of the SALT I Agreements relating to MX basing is the 1972 ABM

Limitation Treaty discussed in chapter 3. The

ABM Limitation Treaty prohibits the deployment of the LoADS ABM system or the present

concept of an Overlay ABM to defend MX missiles deployed either in MPS or in silos. It also

prohibits the deployment of Soviet defenses

that in turn might substantially increase the

need for larger numbers of U.S. strategic

weapons carried aboard both ICBMS and

SLBMS. The value of deploying MX in any

mode protected by any ABM system must be

weighed against the uncertainties in U.S. strategic planning and increases in strategic forces

requirements that might be introduced with

the deployment of a Soviet ABM system.

‘“’’ Protocol to the Interim Agreement, ” in ibid , p. 154

‘ ‘The evolution of the limits on the number of modern submarine launched ballistic missile launchers in the SALT I interim Agreement Protocol are discussed In great detail In Gerard

C Smith’s book, Doubletalk: The Story of SALT (Garden City,

N Y Doubleday, 1980) See especially pp 393-397 and p 428
Ch. 12—Arms Control Considerations and MX Basing Options ● 315

IMPACT OF SALT II ON MX BASING

The SALT II Treaty, signed June 18, 1979, in

Vienna, Austria, would substantially affect MX

basing options were the Treaty to be ratified

and were its terms to remain in effect beyond

December 31, 1985. The Treaty was intended

to limit equally the total number of strategic

nuclear weapons delivery vehicles in the

arsenals of the United States and the Soviet

Union, to place an upper limit on the total

number of nuclear weapons carried by ICBMS,

SLBMS, and long-range bombers equipped with

cruise missiles, or air-to-surf ace ballistic

missiles, and to inhibit the development of

new types of ICBMS. It was also intended to

build confidence in the ability of the two nations to coexist without fear of an unremitting

strategic arms race by providing for an exchange of data on strategic nuclear weapons,

establishing rules for the monitoring of each

other’s compliance with the terms of the treaty, exchanging information on certain activities that might be ambiguous, and continuing the negotiating process leading to one or

more subsequent Strategic Arms Limitation

Agreements. 2

The Treaty was submitted to the Senate on

June 22, 1979, where extensive hearings were

held by both the Committee on Foreign Relations and the Committee on Armed Services.

Before the Senate could take up the report of

the Foreign Relations Committee on the proposed ratification of the Treaty, the Soviet

Union invaded Afghanistan and President Carter formally requested the Senate on January

3, 1980, to defer further action on the Treaty.

The President said in his letter to Senator

Robert Byrd:

In light of the Soviet invasion of Afghanistan, I request that you delay consideration of

the SALT I I Treaty on the Senate floor.

The purpose of this request is not to withdraw the Treaty from consideration, but to defer debate so that Congress and I as President

can assess Soviet actions and intentions, and

devote our primary attention to the legislative

and other measures required to respond to this

crisis. 

The United States has signed the Treaty, as

has the Soviet Union; however, the Soviet

Union has not ratified the Treaty, and has

stated that it will not do so until the United

States indicates whether or not it will complete

the ratification process as is required by the

U.S. Constitution. The United States has not

completed ratification of the Treaty, since

two-thirds of the Senate has not given its advice and consent to do so.

During this period between signature of the

Treaty and either its ratification or rejection,

common understanding of international law

requires the United States to take no action intended to defeat the purposes for which the

SALT II Treaty was negotiated.14 The Reagan

administration has publicly taken the position

that it does not believe itself bound by the

limits of the agreement pending completion of

a careful review of the Treaty. 1

5 Nevertheless,

the United States has observed those provisions of the Treaty imposing quantitative and

qualitative limitations on American strategic

nuclear forces.
316 ● MX Missile Basing

There are several provisions of the proposed

SALT II Treaty that would affect the deployment of the MX were the terms of the Treaty in

force in 1986 or beyond. Some of the Treaty

provisions affect basing modes directly; other

provisions of the Treaty might affect the

testing, operation, or cost of MX deployment,

or might require design changes in various

basing modes to facilitate monitoring the

deployment of mobile ICBMS for compliance

with the terms of the Treaty.

Four basing modes would be explicitly prohibited under terms of the SALT I I Treaty were

the Treaty in force when the MX would be

deployed:

.

2.

3.

4.

Deployment of MX missiles in new, fixed

ICBM silos would be prohibited under

provisions of article IV.

Surface ship mobile deployment of MX

missiles would be prohibited under provisions of article IX. 7

Deployment of MX missiles on inland

waterways, lakes, or the bottoms thereof

would be prohibited under provisions of

article IX.

Deployment of MX missiles in any basing

mode to launch nuclear weapons into

Earth orbit would be prohibited under

provisions of article IX.

Article II of the Treaty defines ICBM launchers countable under the Treaty. MX research,

development, and test launchers must be

unique to the MX missiles unless the United

States would be willing to have less capable

missiles and their launchers counted under the

SALT II limits.’” For example, mobile intermediate range ballistic missiles would be

countable under the SALT I I Treaty limits if

they were tested from MX development facilities or MX deployment sites.

Deployment of MX missiles by backfitting

them into existing Minuteman silos would be

permitted under terms of the SALT II Treaty,

1“’SALT I I Treaty, ” art IV, In Arms Control Agreements, p 215.

“Art IX, clause l(a), ibid , p 225

“Art IX, clause l(b), Ibid

‘9Art IX, clause l(c), ibid

‘“Art 11, Ibid , pp 208-214

even if existing Minuteman silos required

modification to support the larger MX missile. 2’ Deployment of MX missiles to Minuteman II silos would, however, by definition increase the number of Ml RV-countable launchers, thereby bringing the United States closer

to or even exceeding the allowed number of

MIRVed ballistic missiles under provisions of

the Treaty. 22

While the SALT I I Treaty permits modernization and improvements of ICBMS and their

launchers, there is disagreement between the

United States and the Soviet Union as to

whether or not multiple protective shelters

constitute fixed ICBM launchers within the

context of article IV.

The Soviet position is that multiple protective shelters are but one form of fixed ICBM

launchers. ”

The U.S. position is that so long as the multiple protective shelter cannot launch an MX

missile without the aid of an associated

launcher that contains launch support equipment including power supplies, environmental

control equipment, communications equipment, and other missile support equipment,

the shelters would not meet the definition of a

fixed ICBM launcher found in article 11 of the

Treaty. MPS basing for MX would therefore be

permitted were the SALT I I Treaty in force

when the MX was deployed. 24

Article XV of the Treaty requires that any

deployment of the MX missile be made in a

manner that would permit the unimpeded use

of technical means of verification to monitor

U.S. compliance with the provisions of the

“Art IV, ibid , pp 214-215

“Art V, Ibid , pp 220-221

“The Soviet position on MPS deployment for the MX or Minuteman missiles IS described by Strobe Talbott, in “Keeping the

Options Open, ” Endgame: The Inside Story of SALT // (New York

Harper & Row, 1979, 1980), p 162-173, on the basis of Interviews

with senior U S officials Authoritative unclassified discussion of

the Soviet position on this issue is presented in, U.S Congress

Senate Committee on Foreign Relations, SALT // Treaty (Washington, D C U S Government Prlntlng Office, 1979), Part 4, pp

433-437 and Part 5, pp 278-280, 291, 301-302

*“lbld , see also, “Statement of Ambassador Ralph Earle, ” in

U.S Congress, Senate Foreign Relatlons Committee, Ibid , pt 4,

pp 436
Ch. 12—Arms Control Considerations and MX Basing Options ● 317

ployment sometime in the future may mak e

the distinction between horizontal and vertical

shelters significant.

Rebasing Minuteman Ill missiles in an MPS

mode would be constrained were the terms of

the SALT Ii Treaty in force in 1986 when such

deployments could begin. The number of Minuteman I I I missiles that could be deployed

would be limited under terms of article V such

that the total number of ICBMS and SLBMS

equipped with MIRVS could not exceed 1,200,

and the total number of bombers equipped

with air-launched cruise missiIes, MIRVed

ICBMS, and MIRVed SLBMS could not exceed

1,320.26 DOD has proposed to deploy up to 172

B-52 aircraft equipped with air-launched cruise

missiIes,27 and as many as 760 MIRVed SLBMS

in the late 1980’s,28 leaving room for only 388

MIRVed ICBMS under the proposed ceiling on

aggregate number of MIRVed strategic nuclear

delivery vehicles in the SALT II Treaty.

Rebasing of Minuteman Ill missiles could

therefore disrupt current plans to deploy a

fleet of MIRVed Poseidon and Trident SLBMS,

B-52 bombers equipped with air-launched

cruise missiles, and retention of the present

Minuteman Ill force. Furthermore, the small

number of missiles that could be deployed

within the SALT 1I Treaty limits were they in

force beyond 1985 would constrain a Minuteman I I l/MPS system to a MX of Minuteman III

missiles and shelters that would cost considerably more than the optimal mix.

Questions on status of vertical shelters

noted above in connection with MX/MPS

would also require resolution for rebasing of

Minuteman III missiles. Verification issues

arising in connection with MX/MPS would also

arise in the case of rebasing of the Minuteman

III missiles in an MPS mode.

Other basing modes for the MX not explicitly prohibited by the SALT II Treaty do not appear to be as stressful to the monitoring

capabilities of either the United States or the
318 ● MX Missile Basing

Soviet Union as MX or Minuteman Ill deployed

in an MPS mode. Silo basing, with or without

defense, can be monitored readily by national

technical means in the same manner that current deployments of MIRVed ICBMS are monitored. Air-mobile basing of MX could be monitored through national technical means just as

present bomber deployments are monitored.

In addition, air-mobile deployment of MX if

undertaken within the terms of the SALT I I

Treaty would require the use of aircraft with

Functionally Related Observable Differences

(FRODS). Such measures might include the use

of specifically designed aircraft unique to the

air-mobile MX mission or the structural modification of other aircraft of similar types to aid

in their identification as MX missile launching

platforms through use of national technical

means of verification. These measures would

facilitate counting the MX-carrying aircraft

and missiles under the aggregate Iimits on strategic nuclear delivery vehicles and the MI RVed ICBM sublimits.

OTHER PENDING ARMS

AFFECTING

Like the 1962 Partial Test Ban Treaty, the

1976 Threshold Nuclear Test Ban Treaty and

the 1978 Peaceful Nuclear Explosions Treaty

do not directly limit any MX basing decision.

These two treaties, still awaiting U.S. ratification, nevertheless impose limits on certain U.S.

Government activities that in turn affect research and development activities related to

MX basing issues.

The Threshold Nuclear Test Ban Treaty

limits the yield of underground nuclear explosions to not more than 150 kilotons. 29 I n so doing, it limits the ability of the United States to

conduct reseach and development on the

structural hardness and resistance to nuclear

effects of MPS horizontal and vertical structures, command and control systems, command post structures, and vehicles. The Peace-

-“’’’Threshold Test Ban Treaty, ” In Arms CorJtrO/ Agreements,

pp 167-170

Small submarine basing for the MX missile

could be verified relying on the techniques and

technologies presently used to count deployed

SLBMS.

The SALT II Treaty, were it ratified, would

have some effect on the MX basing mode decision, ruling out new ICBM silo basing, surface

ship mobile basing, inland waterway basing,

and orbital bombardment systems on legal

grounds. Other basing modes for the MX missile would be permitted, and with the exception of MPS basing for MX or Minuteman Ill

appear to present few technical challenges to

the capabilities of either the United States or

the Soviet Union to adequately verify each

other’s compliance with terms of the proposed

SALT I I Treaty were the Treaty still in force in

the period 1986 through the 1990’s and

beyond.

CONTROL AGREEMENTS

MX BASING

ful Nuclear Explosions Treaty limits nuclear explosions for peaceful purposes to a yield of

150 kilotons. It also imposes certain additional

limitations on the instrumentation of such explosions intended to reduce the likelihood that

a peaceful nuclear explosion might be used to

hide either nuclear weapons development activities or tests for various nuclear weapon effects. 30 Hence, these two treaties, like the Partial Test Ban Treaty, iimit to some degree the

ability of the United States to test the hardness

of various MX basing modes to the nuclear effects environment in which they might be required to operate.

It is important to note, however, that the

underground nuclear testing program conducted by the U.S. Government in recent

years, chemical explosion simulation tests,

other dynamic stress tests, nondestructive

“’’’Peaceful Nuclear Explosions Treaty, ” Ibid , pp 173-189
Ch. 12—Arms Control Considerations and MX Basing Options 319

tests, and simulations have provided a wealth MX development, there is widespread confiof data necessary to design the MX missile and dence in the ability of the missile to be built

various possible basing modes for it. As a and operated within the design specifications.

resu

It

t of “this vigorous test program related to

FUTURE ARMS CONTROL NEGOTIATIONS

IS very difficult to predict confidently the

future course of international arms control

negotiations. The recent history of th e

Strategic Arms Limitation Talks between the

United States and the Soviet Union serves to illustrate the multiple technical and political

problems confronting would-be arms control

negotiators. ‘

However, both the United States and the

Soviet Union, despite obvious difficulties in

bringing the SALT I I Treaty into force, have

stated their continuing hope for eventual

resumption of arms control negotiations. During ceremonies welcoming Chancellor Helmut

Schmidt of the Federal Republic of Germany,

President Reagan reaffirmed the commitment

of the United States to negotiations leading to

the reduction of arms in Europe within the

SALT framework. The President promised

“meaningful negotiations as to Iimit those very

weapon s.”

The Soviets too have expressed their continuing desire for a resumption of arms control

negotiations. For example, Leon id Brezhnev,

General Secretary of the Communist Party of

“See tor example, te~tlmony of various publlc officials and

private witnesses on the pro; and cons of the ratlflcatlon of the

SAL T II Treaty In U S Congress, Senate Committee on Foreign

Relatlons, ‘5AL T II Treaty, Volumes f Through 5 (Washington,

D C U S Government Prlntlng Off Ice, 1979), U S Congress, Senate Comm Ittee on Armed Services, M1/ltary /mp/icatlons of the

SAL T // [reaty, Vo/umes I Through 6 (Washington, D C U S

Government Prlntlng Off Ice, 1979) See also Strobe Talbott, op

clt , Robert P La brie, SALT HandbooL’ Key Documents and

/$51)e$, 1971- /979 (Washington, D C American Enterprise lnstltute, 1979) For an Intere\tlng account of Soviet views on the

problems of negotiating SALT, see Samual B Payne, Jr , The

$o~ let Union and SALT (Cambridge, Mass MIT Press, 1980)

““Vlslt of Chancellor Helmut Schmidt of the Federal Republlc

of Germany, ” w eehly Cornp//at/on of Prestdentla/ Documents,

VOI 17, No 21 (May 25, 1981), p 547 The commitment of the

United State~ to renew arms control efforts was made by Secretary Halg to the NATO Foreign Mlnlsters during hls speech of

May 4, 1981 See John M Coshko, “ Halg Tells NATO of New

Plan for Talk$ With Soviets, ” Lt a$hlngton Post, May 5, 1981

the Soviet Union, in speaking to the 26th Congress of the Party, said:

We once more issue an urgent appeal for restraint in the sphere of strategic armaments.

The peoples of the world must not be allowed

to live under the threat of a nuclear war being

unleashed. The I imitation of strategic arms

and their reduction is an extraordinary problem. On our part, we are ready to continue

without delay appropriate talks with the

United States of America while preserving

everything positive that has been achieved up

to now in this sphere.

The interest of both the United States and

the Soviet Union in continuing their bilateral

dialog on arms control suggests a need to

understand better the impact of the MX basing

decision on some of the problems arms control

negotiators may face in the future.

MX missiles deployed in silos, on small submarines, or in an air mobile mode present few

new arms control negotiating problems. These

basing modes are either extensions of existing

basing modes for strategic nuclear weapons

delivery vehicles (SNDVS) or have been previously considered during the Strategic Arms

Limitation Talks. * As a result there appear to

be few new or unique arms control negotiating

or verification problems associated with these

basing modes. Extension of past arms control

negotiating and verification practices would

enable both the United States and the Soviet

Union to conclude an arms control agreement

) “’Proceedings of the 26th CPSU Congress, Volume 1 Brezhnev Report, ” [n Foreign Broadca$t Publication Ser;ice, Dal/y

Report Soviet Union, VOI I I 1, No 36, Supplement 1, Feb 24,

1981, p 20

‘Air-to-surface balllstlc mls$iles and the atrcraft carrying them

would be a permitted MX basing mode were SALT I I In effect In

the late 1980’s provided the mlsslles were not tested before the

expiration of the Protocol to the SALT I I Treaty on Dec 31, 1981,

and that the aircraft carrying the mlsslles were equipped with

FRODS to fac II It ate verlf Icatlon
320 ● MX Missile Basing

permitting deployment of the MX missile in

one or more of these modes which would still

be verifiable using national technical means.

Surface ship mobile deployment of the MX

missile, as noted earlier, is prohibited by the

terms of the SALT I I Treaty because no formula could be negotiated to permit adequate

verification without reducing surface ship

mobile ICBM survivability to an unacceptable

level. The principal arms control negotiating

problem is the development of a formula permitting deployment of surface ship mobile MX

in a relatively survivable manner on the one

hand, and adequate verification of the number

of missiles so deployed on the other. U.S. deployment of a surface ship mobile MX would

establish a precedent for Soviet deployment of

a comparable system. However, the United

States would want to be certain that the ability

to count the number of Soviet surface ship

mobile ICBMS would not be unduly hindered

should the Soviets opt for a mobile ICBM

deployed in that mode at some time in the

future. The problem from a weapon system

survivability perspective is that steps that

might be taken to faciIitate arms control agreement verification rapidly reduce the survivability of surface ship mobile based ICBMS (see

ch. 7 of this report).

Deployment of MX missiles on surface ship

platforms equipped with FRODS to aid verification of an arms control agreement would

facilitate detection, identification, and maintenance of trail at sea, thereby reducing survivability to a very low rate. Limiting areas of

surface ship mobile operation would facilitate

counting the vessels, but would also permit the

Soviets to concentrate their antisurface warfare-monitoring assets on the general areas of

deployment, thereby reducing the long-term

survivability of the surface ship platforms.

MX missiles deployed in an MPS mode with

or without defense would radically alter the

arms control negotiating environment.

The number of ICBMS deployed in fixed

silos cannot be readily augmented without

considerable testing of alternative means for

launching missiles. The time consumed and

the highly visible activities involved in the construction of ICBM silos make it highly unlikely

that such silos could be deployed in large

numbers without being detected by national

technical means of arms control agreement

verification. Other techniques for launching

ICBMS might be developed that would go unnoticed, but such techniques could be

detected when and if extensive testing were to

occur.

Uncertainty about the possibility of detecting a clandestine deployment of ICBMS makes

it difficult for either the United States or the

Soviet Union to justify the risks of clandestine

ICBM deployment unless such a deployment

could be large enough to make a significant

difference in the strategic balance. While judgments as to the number of clandestinely deployed ICBms or RVS will vary among analysts,

the threshold for strategic significance

diminishes quickly as the number of ICBMS

and/or RVS permitted decreases.

MPS deployment by the Soviets for a future

land-mobile ICBM might create a situation in

which they would find it relatively easy to

either openly abrogate or clandestinely violate

on arms control treaty limiting the number of

land-mobile ICBMS deployed. An MPS system

would deploy an entire infrastructure of missile shelters, command and control systems,

transportation systems maintenance facilities,

personnel, and other resources needed to support any mobile ICBM. Rapid, overt deployment of stockpiled missiles (“breakout”)

in excess of future treaty limitations in a sudden, open act of treaty abrogation might therefore be an attractive, relatively low cost option

for increasing Soviet strategic forces.

The existence of the MPS infrastructure

might also encourage clandestine attempts to

deploy excess land-mobile ICBMS. Such deployments could be especially difficult to detect after they had occurred, and MPS deployment of land mobile ICBMS might lead to a

situation in which it would not be possible to

adequately verify violation of an arms control

agreement.
Ch 12—Arms Control Consideration and MX Basing Options ● 321

MX/MPS creates an unprecedented need for

future arms control agreements to specify

cooperative measures for verifying the number

of mobile ICBMS deployed by either side. This

subject raises serious negotiating problems, as

each procedure related to the verification of

the number of MX missiles deployed by the

United States must be designed with a hypothetical Soviet mobile ICBM in mind as well.

Furthermore, a series of procedures, useful for

verification purposes but perhaps not essential, would have to be included in order to ensure that those procedures essential for purposes of counting the number of large, land

mobile IC BMs deployed by either side emerge

from the negotiating process.

MX deployed in an MPS mode would further

complicate the process of strategic arms control negotiation limitation by placing a very

high value on Soviet agreement to an RV limitat ion Previous SALT negotiations have attempted to balance specific United States and

Soviet advantages in various areas of strategic

weapons and Strategic nucIear weapon deIivery systems in order to conclude an agreement that was baIanced need WhiIe views differ on

the degree of success U S and Soviet negotiators have had in attempting to reach a bal -

anced agreement, M X M P S would further com -

plicate the negotiating process The great sensitivity of the MX,’MPS survivabiIity to the

numbers of Soviet RVS and the potentiaI

growth in the Soviet RV inventory coupled

with the great cost of the United States MPS

system wouId put Soviet arms control negotiators in a very strong negotiating position An

agreement Iimiting the number of Soviet RVS

now or in the future would enable the United

States to plan and budget for MX/MPS; the

Soviets could therefore use their willingness to

agree to RVI i m i tat ions as a ‘‘bargaining chip’

to persuade the United States to agree to other

Iimitations on strategic weapons of keen interest to the Soviets

MX, MPS also complicates arms control

negotiations by making it much more difficult

to accept any agreement that would freeze

strategic force modernization efforts unless

such a freeze were absolute. The sensitivity of

MX/MPS survivability to the number of RVS de83-477 0 - 81 - 22

ployed by the Soviets would require the United

States to take a position that in essence required the Soviets to stop all construction and

deployment of systems not operational as of a

certain date even though MPS construction

would have to continue until the number of

shelters built exceeded the number of threatening Soviet RVS. Failure to obtain this kind of

cutoff of new deployments wouId jeopardize

the survivability of MX missiles deployed in an

MPS mode.

Minuteman III rebased in an MPs mode

wouId simiIarly complicate future arms control negotiations. Rebasing of Minuteman I I I

would be as sensitive to the number of Soviet

RVS deployed as would be MX/MPS deployment; the relative bargaining leverage gained

by the Soviets for MX/MPS would also be

gained with Minuteman I I l/MPS. Cooperative

measures for verifying U.S. compliance with a

limitation on the number of mobile, relatively

small ICBMS would also have to be negotiated,

again on the premise that U.S. deployment of a

mobile ICBM would at some point be matched

by a similar but not necessarily identical

Soviet mobile ICBM deployment.

As a result, MX/MPS and Minuteman III/MPS

would create a need for arms control negotiations to become ever more deeply and intimately involved in the specification of detailed procedures of weapon system deployment

and peacetime operation.

Defended MX/MPS would add the great

uncertainties associated with the reopening of

discussions on ABM system limitations to the

other negotiating problems noted above.

While the present ABM Treaty seriously inhibits development, testing, and deployment

of the LoADS ABM system, it equally inhibits

development and deployment of Soviet ABM

systems. Were the Soviets to be ret ieved of this

legal inhibition, they might well deploy an

ABM system that would affect the ability of

U.S. ICBM and SLBM RVS to successfully attack Soviet targets, generating requirements

for significantly larger

strategic forces. The great

duced in calculating the

developing requirements

numbers of U.S.

uncertainties introstrategic balance,

for U.S. strategic
322 ● MX Missile Basing

forces, and procuring the necessary forces tional increment of survivability that a LoADS

would have to be weighed against the addi- ABM might provide the MX.

ARMS CONTROL AND STABILITY

Arms control seeks as a general goal to

reduce the likelihood of war. Efforts to maintain international stability and control the

escalation of severe international crises are

therefore often considered an integral component of arms control. The procurement and deployment of strategic forces in a manner that

reduces the incentives to continue modernization or procure additional numbers of forces

are also thought to be consistent with arms

control efforts. The selection of a basing mode

for the MX missile may therefore have broader

implications for arms control beyond the

negotiation of new international agreements.

The deployment of the MX missile in a survivable basing mode is generally thought to be

an important adjunct to the management of

severe international crises. High confidence by

American and Soviet decisionmakers in the

survivability of the MX force would minimize

incentives for either side to strike first. Survivable basing wouId allow American decisionmakers to wait out a crisis without resorting to

the use of force out of concern that if the MX

missiles were not used, they might be preempted and unavailable later during a crisis. Survivable basing for the MX missile would reduce

incentives of the Soviet leadership to attempt

preemption because they could not be confident of destroying a sufficiently large fraction

of the force to effectively limit the ability of

the United States to retaliate. Survivable

basing would also reduce Soviet incentives to

initiate an attack out of fear that the United

States would strike first to forestall Soviet

preemption.

As noted throughout the earlier chapters of

this study, most basing modes for the MX missile would provide survivability when fully

deployed; several including small submarine

or air mobile MX basing would provide substantial survivability concurrent with or shortly

after initial operating capability. However, in

some operational concepts, air mobile basing

might create a situation during a crisis in which

the Soviets might mistake a widespread, simultaneous launch of MX-carrying aircraft undertaken to enhance survivability as strategic warning of an impending American attack. Such a

perception would add instability to a crisis.

While there are many other operational concepts for an air mobile force which might overcome this concern, the possibility that the

Soviets might perceive the airborne operation

of a large fraction of the air mobile MX force

as a provocative action during a severe crisis

cannot be completely discounted.

As noted above, the selection of a basing

mode for the MX missile that added incentives

to increase the size of strategic nuclear forces

would be inconsistent with the general goals of

arms control. Most basing modes for the MX

missile assessed in this study satisfy this

criterion; MPS with or without the LoADS defense, however, would provide a strong incentive for the Soviets to add to their inventory of

RVS. Finally, MX/MPS would make terminating

a buildup of U.S. and Soviet strategic forces

more difficult than other MX basing modes

because the United States could not stop constructing MPS until the number of shelters exceeded the number of RVS in the Soviet inventory that might pose a threat to MX/MPS survivability. The Soviets, on the other hand,

might find it difficult to stop adding RVS to

their inventory unless they had clear evidence

that the United States had halted its MPS construction program. Thus, MPS with or without

the LoADS ABM defense would pose the most

severe challenges to the long-term ability of

the United States to achieve some of its stated

arms control objectives.
APPENDIXES
Appendix A

LETTER OF REQUEST

T ECHNOLOGY A SSESSMENT B OAR O Congress of the United States JOHN H. GIBBONS

MORRIS K . UDALL . ARIZ.. CHAIRM A N Directo r

TED STEVENS. ALASKA, VICE CHAIRMAN O FFICE OF T ECHNOLOGY A SSESSMEN T DANIEL DESIMONe

EdWARD M. KENNEDY. MASS. GEoRGE E. B rownJr.n.. CALIF.

Deputy Director

ERNEsT F. Houllings S.C. JOHN O DI NGELL MICH . W ASHINGTO N , D.C. 2051 0

ADLA E. STEVENSON, - LARRY WINN, JR , KANs.

ORRIN a. HATC H, UTA H CLARENCE E. MILLER. OHIO

CHArles MCC. MAT HIA S. Jr, M D . JOHN W. WYOLER, N.Y.

JOHN H. GIBBONS

May 8, 198 0

Dr. John H. Gibbons

Director

Off ice of Technology Assessment

Washington, D. C. 20510

Dear Jack :

The Administration has proposed that the United

States build and deploy the new MX missile in Utah and Nevada.

Although the case for a new strategic missile is understood,

the missile basing system remains controversial, and the

trade-offs involved remain unclear. In view of the critical

importance of MX to the future military security of the United

States, the enormous size of the proposed budget, and the

tremendous impact which MX deployment may have on the regions

where such deployment takes place, Congress as a whole ought

to have the best obtainable information and analysis about

MX basing. There would be particular value in an assessment

which, while drawinq upon whatever military and intelligence

information is pertinent, would be independent of the Defense

Department and the Administration.

We therefore request that OTA prepare and submit

to the Board as soon as possible a plan for an assessment

of how the MX missile might be based. If this plan indicates

that the time and money required for a study are not excessive,

we expect to reuuest that the Board approve the initiation of

such an assessment.

The study would describe and evaluate the Administration proposal, selected alternatives which the Defense

Department has studied, and additional possible basing modes

which seem worthy of consideration. Various types of multiple

protective structure (MPS) systems, alternatives to MPS, and

alternatives to land-basing should be addressed.

Specifically, OTA’S evaluation should address the

suitability of each basing concept in terms of such issues as

technical risk, survivability (includinq detectability and

hardness) , reliability, the time required for deployment, etc.

To the extent necessary to evaluate basing systems, the study

should also address the projected Soviet threat, and possible

Soviet responses to an MX system.

325
326 “ MX Missile Basing

Dr. John H. Gibbons

May 8, 1980

Page Two

In order to clarify the trade-offs that must be

made in choosing a basing system, the study should address

basing proposals in the following contexts:

(1) the peacetime strategic balance, in which U.S.

strateqic forces should preserve and enhance stability and

security; (2) likely future efforts to negotiate arm= control

treaties, in which U.S. strategic forces should make such negotiations easier rather than more difficult; (3) a severe

crisis or limited war, in which U.S. strategic forces should

enhance our ability to manage the crisis and to terminate it

on acceptable terms; and (4) a major war, in which U.S.

strategic forces should make an enemy regret that he had

refused to be deterred.

To the extent necessary for a comparison of basing

systems, the study should evaluate the environmental impact

of construction and peacetime operation of the various alternatives. The effect which the choice of basing system

might have on the effects of war on the civilian population

and economy should also be addressed.

The final topic of the study should be an estimate

of the cost of the Administration proposal and of any alternatives that appear worthy of serious consideration. We request that you explore the possibility of a cooperative effort

between OTA and the Congressional Budget Office, in which CBO

would apply their expertise concerning the budgetary impact of

choices Congress might make. If such CBO cooperation appears

to be likely, it should be reflected in the assessment plan

submitted to the Board.

We do not expect or desire that OTA attempt to reach

conclusions about whether the Administration proposals, or particular alternatives, should be adopted. The completed assessment should present a clear analysis of the options available

to Congress regarding the MX basing, an explanation of why these

particular options are worthy of consideration, and a statement of the major advantages and disadvantages of each option.

While OTA should draw upon appropriate classified

data regarding both U.S. capabilities and the Soviet threat,

the report should contain at least a summary that is unclassified.
App. A—Letter of Request . 327

Dr. John H. Gibbons

May 8, 1980

Page Three

We recognize that an assessment of this sort

cannot be carried out overnight. Nevertheless, timely

completion of the assessment is essential. The timetable

should allow for OTA staff to brief Members of Congress and

their staff on the study's preliminary results after the

August, 1980 break, and a final report should be ready

prior to the convening of the 97th Congress.

With best wishes,

Cordially,

\ k &Y ~

1 /

1 /

1

,t. f“ ~.0.L/! !

ORRIS UD= D’ ?5!lV3’VElfS

CHAIRMAN ) VICE CHAIRMAN
Appendix B

MX MISSILE

The MX missile is a four stage intercontinental

ballistic missile (ICBM) presently in full-scale

engineering development. Like its predecessor, the

Minuteman Ill, the first three rocket stages are

sol id propellant, with a Iiquid-fueled fourth stage/

post-boost vehicle. Weighing about 192,000 lb, the

missile will be 70 ft long, with a 92 inch diameter.

The MX is a MIRVed (multiple independently targetable reentry vehicle) missile, and will carry 10

MK 12A warheads. The Minuteman I I I carries three

MK 12As. A comparison between the MX and the

Minuteman is given in figure B-1.

Figure B-1 .—Missile Comparison

. %’

-192,000 lb

7(

A drawing of the MX fourth stage postboost vehicle (PBV) is shown in figure B-2. We see that it is

designed to be able to carry 12 MK 12A warheads,

or alternatively, 11 advanced ballistic reentry

vehicles [A BRV). SALT I I would limit the number of

reentry vehicles (RVS) to 10. The inertial measuring

unit (I MIJ) of the MX’S guidance and control system

is a significant advance in guidance technology

over Minuteman, and is designed to give the MX

much greater accuracy on target.

Also unlike Minuteman, the MX missile will be

“cannisterized,” to facilitate handling and movement of the missile, and to provide for the missile’s

environment control. The MX is also designed to be

“cold launched” from the cannister. This means

that for launch, the missile is first gas-expelled from

the cannister, at which point it fires its first stage.

The MX missile is scheduled to begin flight testing in January 1983, for a total of 20 tests before

system is in initial operating capability. The last

flight test is scheduled for April 1986. These tests

will check for a wide variety of missile functions

and of associated equipment, including rocket

stage performance, guidance and control, reentry

system performance, range and payload capability,

retargetting, and many others.

SOURCE: U.S. Air Force.

328
App. B—MX Missile . 329

Figure B.2.—MX Post Boost Vehicle

MK 12A ABRV

Warheads

Battery -

Oxidizer

Cold gas

pressurization

Fuel

Guidance & control

SOURCE: U.S. Alr Force.

Guidance & control
Appendix C

ACRONYMS AND

GLOSSARY

List of Acronyms

A&CO — assembly and checkout

ABM – antiballistic missile

ABNCP — Airborne National Command Post

AFY – acre-feet per year

AIRS — Advanced Inertial Reference

Sphere

ALCC — Airborne Launch Control Center

ALCM — Air-Launched Cruise Missile

AMST – Advanced medium short takeoff

and landing aircraft

ANMCC – Alternate National Military

Command Center (Ft. Richie, Va.)

A SAT — antisatellite

ASW – antisubmarine warfare

BMD – ballistic missile defense

BMDSCO M – Ballistic Missile Defense Systems

c’

CBO

CEP

DE IS

DOD

DU

EAM

EHF

EIS

EMP

EMT

FOC

FROD

GBS

GPS

HF

ICBM

ICT

IGPS

I MU

I o c

kT

LF

Command (U.S. Army)

— command, control, and

commun i cat ions

– Congressional Budget Office

— circular error probable

– draft environmental impact

statement

– Department of Defense

– defense unit (LoADS)

– Emergency Action Message

— extremely high frequency

— environmental impact statement

— electromagnetic pulse

— equivalent megatonnage

– full operational capability

– functionally related observable

difference

– Ground Beacon System

– Global Positioning System

– high frequency

— intercontinental ballistic missile

— intelligence cycle time

– Inverted Global Positioning System

— inertial measuring unit

— initial operating capability

– kiloton

– low frequency

LoADS

LUA

MAP

MaRV

MF

“1

;’I RV

MPS

MT

MWe

NCA

NEACP

NMCC

nm i

NORAD

NTS

O c c

ORV

PLU

psi

RDT&E

RV

SAC

SALT

SATCOM

Scc

SHF

SIOP

SLBM

SWFLANT

SWFPAC

TEL

UHF

USAF

USN

VLF

– low altitude defense system

– launch under attack

— multiple aim point

— maneuverable reentry vehicle

— medium frequency

— square miles

— multiple independently targetable

reentry vehicle

— multiple protective shelters

— megaton

— megawatts of electricity

— National Command Authorities

— National Emergency Airborne

Command Post

– National Military Command Center

(Pentagon, Washington, D. C.)

— nautical mile

– North American Aerospace

Defense Command

– Nevada Test Site

– Operational Control Center

– Off-Road Vehicle

— preservation of location

uncertain y

– pounds per square inch

— research, development, test, and

evaluation

— reentry vehicle

– Strategic Air Command (U.S. Air

Force)

– Strategic Arms Limitation Talks

– Satellite communications

– Standing Consultative Commission

— super high frequency

– Single Integrated Operational Plan

— submarine-launched ballistic

miss ile

– Strategic Weapons Facility,

Atlantic, U.S. Navy

– Strategic Weapons Facility, Pacific,

U.S. Navy

— transporter-e rector-1 auncher

— ultrahigh frequency

– U.S. Air Force

– U.S. Navy

— very low frequency

330
App. C—Acronyms and Glossary | 331

Glossary

ABM Treaty: Formally entitled the “Treaty between

the United States of America and the Union of

Soviet Socialist Republics on the limitation of

antiballistic missile system s,” this Treaty limits

the deployment of antiballistic missile systems

by the United States and the Soviet Union to

specific sites and to specific technical characteristics. The Treaty is of unlimited duration,

subject to review every 5 years. The Treaty was

amended in 1974 Iimiting the deployment of antiballistic missile systems to one site containing

no more than 100 interceptor launchers and

missiles.

Acoustic Transponders: Navigation aids attached to

the ocean floor which when queried respond by

emitting a signal permitting a submarine or surface ship to determine its location with great

precision.

Acquisition Costs: The amount of money invested in

research, development, test, production, and

procurement of a weapon system but not covering costs of operating and maintaining the

weapon system once it has reached operational

capability and is deployed with military forces.

Adaptive Preferential Defense: A tactic for multiplying the effectiveness of an antiballistic missile

defense system by defending only a small

proportion of the total number of targets under

attack.

Ad Hoc Retargeting: The ability to construct

strategic nuclear attacks which have not been

previously included in the wide range of preplanned attack options comprising the U.S.

Single Integrated Operational Plan.

Advanced Inertial Reference Sphere (AIRS): An advanced guidance system presently being developed for the MX missile.

Airborne Launch Control Center (ALCC): Aircraft

used to launch MX missiles deployed in a multiple protective shelter basing mode.

Air-Launched Cruise Missiles (ALCM): Small unmanned airplane-like vehicles armed with nuc I ear weapons.

Alert Rate: The number of U.S. strategic nuclear

delivery vehicles armed, manned, or deployed

on combat patrol during peacetime conditions.

Antisubmarine Warfare (ASW): Methods of warfare

utilizing specialized sensors, data processing

techniques, weapons platforms, and weapons

intended to search for, identify, and destroy

submarines.

Area Kill: See Barrage Attack.

Arms Control Agreement Verification: The process of

collecting and analyzing information to determine whether or not parties to an international

arms control agreement are complying with its

terms.

B-52: A heavy intercontinental range strategic

bomber deployed by the United States. B-52

bombers can be equipped with gravity bombs,

short-range attack missiles, or air-launched

cruise missiles.

Ballistic Missile Defense (BMD): Systems for defense

against missiles which follow trajectories resulting from gravity and aerodynamic drag following termination of powered flight. This term

is used interchangeably with ABM systems.

Barrage Attack: An attack using nuclear weapons to

cover a large area with a given severity of blast

and/or thermal nuclear effects.

Baseline Design: As used in this study, the term

“baseline design” refers to the Air Force MX

basing design, May 1981. This design includes

both the design of the MX missile as well as the

mu Itiple protective shelter basing mode.

Blackout: A condition in which the heat and radiation from an atmospheric nuclear explosion

ionize the surrounding volume of air causing

radar signals passing through the affected

region to be absorbed or reflected.

Breakout: As used in connection with discussion of

the LoADS ABM system, breakout refers to the

rapid deployment of the LoADS defense unit by

use of explosive charges to break through the

top of the protective shelter permitting the

defense unit to activate its radar and launch its

interceptor missiles.

Circular Error Probable (CEP): A measure of the accuracy with which a weapon can be delivered.

It is the radius of a circle around a target of

such size that a weapon aimed at the target has

a 50-percent probabiIity of falIing within the circle.

Cold launch: The use of a gas generator to build up

steam pressure inside a cannister housing a

ballistic missile which forces the missile out of

the cannister prior to the ignition of the first

stage rocket motor. The temperature of the

steam used to eject the missile from the cannister is quite hot; however it is substantially

less than the many thousand degrees Fahrenheit

of the rocket motor exhaust, and hence the

term “cold launch. ”

Command, Control, and Communications (C3

): The

systems and procedures used to ensure that the

President, senior civilian and military officials,

and U.S. strategic nuclear forces remain in com-
332 ● MX Missile Basing

munication with each other, able to plan for the

use of nuclear weapons, to choose among options, to deliver orders to the forces in the field,

and to receive word that the forces have executed or attempted to execute their orders

during the course of peacetime or wartime

operations.

Damage Expectancy: The probability that a nuclear

weapon wilI arrive at and destroy its target.

“Dash-on= Warning”: A concept in which MX missiles

on vehicles are dispersed rapidly upon receipt

of warning that an attack appears underway to

a nearby shelter where the MX missile is quickly

inserted.

Desertification: The significant reduction of biologic

activity and accelerated deterioration of soils in

arid land ecosystems.

Dynamic Pressure: A measure of the gusting winds

folIowing the shock front produced by a nuclear detonation.

Emergency Action Message (EAM): Orders to U.S.

strategic offensive forces for the initiation or

termination of a strategic nuclear attack.

Electromagnetic Pulse (EMP): A sharp pulse of

electromagnetic energy produced by a nuclear

explosion capable of damaging unprotected

electrical and electronic equipment at great

distances.

Endoatmospheric Defense: ABM systems which

operate in the sensible portion of the Earth’s atmosphere, typically at altitudes from the

ground to 100,000 ft.

Environmental Impact Statement (EIS): A description

of the possible range of impacts on the socioeconomic and physical environments prepared

by the Air Force pursuant to the requirements

of the National Environmental Policy Act.

Endurance: The ability of a strategic weapons

force– including both strategic nuclear

weapon delivery vehicles and associated command, control and communications systems —

to survive and function for weeks or months

following a nuclear exchange.

Equivalent Megatonnage: The yield of a nuclear

weapon in megatons, to the two-thirds power. A

measure of the area that can be barraged to a

given overpressure.

Exchange Ratio: The number of nuclear weapons

that must be used by an attacker to destroy one

nuclear weapon belonging to an adversary.

Exoatmospheric Defense: ABM systems that operate

outside the atmosphere.

External Navigation Aid: Devices external to a missile

or platform used to provide information to the

missile or missile platform on its position and

velocity.

Flush: A launch of manned aircraft or a rapid deployment of submarines or surface ships in response to either tactical or strategic warning to

preserve as much of the force as possible in the

event of a nuclear attack.

Fractionation: The division of the payload of a missile into a larger number of warheads with

smaller individual yields.

Fugitive Dust: Dust generated by construction activities and vehicular traffic on and off roads

which migrates from the area immediately surrounding such activities to distant locales.

Full Operational Capability (FOC): The date on which

the planned number of weapon systems has

been deployed and control of the forces given

to the operational military command for the entire force.

Functionally Related Observable Differences (FRODS):

Structures added to similar airframes or naval

vessels to differentiate among them thereby facilitating direct observation by national technical surveillance systems permitting verification of each party’s compliance with the terms

of an arms control agreement.

Global Positioning System (GPS): A system of artificial satellites currently being deployed by

the United States in the 197o’s and 1980’s intended to provide accurate position and velocity data to facilitate improved navigation and

missile accuracy.

Hardness: A measure of the resistance of an object

to the effects of nuclear detonations.

Hard Targets: Targets that have been specifically

designed to withstand the blast, thermal radiation, and other effects of nuclear weapon

detonations nearby.

Horizontal Shelters: Protective shelters for the MX

missile constructed such that the missile and its

launch support equipment are inserted into the

structure and stored in a horizontal position.

Inertial Guidance: A guidance system for missiles,

aircraft, and ships which relies solely on a selfcontained set of instruments carried aboard the

platform to determine changes of velocity and

position from a known initial point.

Inertial Measuring Unit (IMU): A device installed in

the uppermost stage of a ballistic missile used

to derive missile accelerations throughout

flight, and to obtain velocity and position data

which is used to navigate the missile.

Initial Operating Capability (IOC): The date on which

a small number of weapon systems is turned
App. C—Acronyms and Glossary ● 333

over to the commander of a military force for

incorporation into the operational forces of the

United States.

Intelligence Cycle Time (lCT): The period of time

from the sighting of a target to the time

weapons can be delivered against it.

Inverted Global Positioning System (IGPS): A concept

for a system of ground-based radio beacons to

be used to provide navigational information for

mobiIe MX missiIes and various platforms carrying such missiles.

Kill Vehicles: Independently guided nonnuclear

weapons that are used in the exoatmospheric

antiballistic missile systems to destroy incoming nucIear weapons.

Kilofeet: 1,000 f t.

Knot: 1 nautical mile per hour.

Kilotons (kT): Equivalent to 1,000 tons of TNT.

Launch Under Attack (LUA): A doctrine for strategic

forces requiring their launch upon receipt of

warn ing of an attack on the United States.

Layered Defense: An antiballistic missile system

consisting of both an exoatmospheric defense

and an endoatmospheric defense.

Lifecycle Costs: Costs of research, development,

test, procurement, operation, maintenance,

modification, and dismantling of a weapon

system over the period from initial research and

development to retirement or dismantling of

the last weapon system.

Low Altitude Defense System (LoADS): A system proposed by the Army as an endoatmospheric antiballistic missile defense.

LoADS Defense Unit (DU): This consists of a radar, interceptor launchers, and interceptors mounted

on a mobile unit and deceptively deployed in

conjunction with MX missile deployments.

Maneuvering Reentry Vehicle (MaRV): An independently targetable reentry vehicle which can

maneuver to evade balIistic missile defense or

to obtain better accuracy.

Microwave Radiometers: Instruments that can

detect electromagnetic emissions such as radio

transmissions or radar signals used to detect

and identify the transmitting platform.

Minuteman: An ICBM deployed by the United

States in two models. Minuteman II is a three

stage, solid fueled missile armed with a single

nuclear weapon; Minuteman I I I is armed with

three independently targetable nuclear weapons.

Multiple Aim Point: A term for basing a force of

ICBMS among a larger number of protective

missile shelters. See Mu/tip/e Protective Shelter.

Multiple Protective Shelter (MPS): A term describing a

basing mode for land-based missiles in which

missiles are deployed among a large number of

hardened structures. These are designed and

distributed to provide protection against nearby nuclear weapon detonations.

MX Missile: Missile X or missile experimental; the

proposed U.S. Air Force advanced ICBM.

Northern Minuteman Wings: Minuteman missiles

deployed at Malstrom Air Force Base, Mont.;

Grand Forks, N. Dak.; Warren Air Force Base,

Wyo.; and Ellsworth Air Force Base, S.Dak.

National Technical Means of Verification (NTM):

Technical intelligence information collection

systems which are under national control for

monitoring compliance with the provisions of

an arms control agreement. NTM include

photographic reconnaissance satellites, aircraft

based systems such as radars and optical

systems, as well as sea- and ground-based

systems such as radars, antennas for collecting

telemetry, and seismic recorders,

National Command Authorities (NCA): The President,

the Secretary of Defense, and the Joint Chiefs

of Staff and their designated successors

authorized to initiate an order for the use of

nuclear weapons.

National Emergency Airborne Command Post

(NEACP): A modified Boeing 747 transport aircraft equipped with a wide array of communications equipment for use by the President

and other members of the National Command

Authorities in the event of a nuclear war.

Nevada Test Site (NTS): A facility where the United

States detonates nuclear explosive devices

underground.

North American Aerospace Defense Command

(NORAD): A joint U.S.-Canadian military command responsible for outer space, air space

surveillance and air defense of the North

American Continent.

Ocean Mobile Systems: Basing of the MX missile by

deploying the missile aboard small submarines

or surface ships.

Operational Control Center (OCC): Peacetime

operating base for logistic support and physical

security for the MX missiIe force.

Overlay: concept for exoatmospheric antiballistic

missile defense.

Overpressure: The transient pressure, usually expressed in pounds per square inch, exceeding

the ambient atmospheric pressure, due to the

shock wave generated by an explosion.
334 ● MX Missile Basing

Permeable Metal: A metal with a strong magnetic

response.

Point Kill: The destruction of a hardened target at a

fixed location.

Postattack: The period of time following a nuclear

exchange between the United States and the

Soviet Union.

Preattack: The period of time preceding a nuclear

exchange between the United States and the

Soviet Union.

Preservation of Location Uncertainty (PLU): The

engineering of the MX missile, its transporterIauncher vehicle, the protective shelter, to prevent an outside observer from determining the

precise location of the MX missile among the

many available shelters which could house it.

Rad: A unit of absorbed dose of radiation.

Reentry Vehicle: That portion of a ballistic missile

which carries the nuclear weapon and reenters

the Earth’s atmosphere to reach it target.

Refit: The resupply of naval vessels with fresh food,

fresh water, fuel, other consumables, installation of new equipment, repair of equipment on

board, and the embarkation of a new crew.

Reliability: The ability of a missile system to carry

out an order from its receipt to the detonation

of a weapon against its target.

Responsiveness: A measure of the length of time required for U.S. strategic forces to receive,

authenticate, and implement an order from the

National Command Authorities for the use of

nuclear weapons.

Retargeting: The process of assigning new targets

for a strategic nuclear weapon delivery vehicle.

Readable TEL: A missile-carrying vehicle chosen for

a previous U.S. Air Force MPS design, that

could transport, erect to a vertical position, and

launch the MX missile.

Reentry Vehicles (RV): As used in this report, reentry

vehicles contain nuclear weapons.

SAFEGUARD: An antiballistic missile system

deployed by the United States in the early

1970’s containing both large and small phased

array ABM radars and exoatmospheric and endoatmospheric interceptors.

SALT: An acronym for the bilateral negotiations between the United States and Soviet Union on

the subject of Strategic Arms Limitation Talks.

SALT I refers to the agreements concluded in

May 1972 including the ABM Treaty and the interim Agreement on Strategic Offensive Nuclear Weapons.

SCC: The joint U.S.-U.S.S.R. Standing Consultative

Commission, a deliberative and negotiating

body established by the ABM Limitation Treaty

which meets semiannually to review implementation of the ABM Limitation Treaty and other

Strategic Arms Limitation Agreements in force.

Shock Front: The leading edge of a wave of air

pressure created by an explosion.

Shoot-Look-Shoot: A tactic for attacking MX

deployed in an MPS or defended MPS mode in

which the attacker fires a salvo of reentry

vehicles, observes the effects of such an attack,

and then attacks shelters left undamaged by the

first attack.

Silo: A fixed, vertical structure housing an ICBM

and its launch support equipment including

power supply, communications equipment, and

environmental control equipment which has

been constructed to withstand the effects of

nearby nuclear explosions.

Single Integrated Operational Plan (SIOP): The

preplanned nuclear attack options prepared for

the consideration of the President by the

Department of Defense.

Site Activation Task Force: A Joint U.S. Air Force and

U.S. Army team which will check out and accept individual MPS shelters when the construction contractor believes construction has been

completed.

Small Submarine Basing: A basing concept utilizing

submarines displacing 2,500 to 2,800 tons on

which MX missiles are deployed and operated

in deep ocean waters within 1,000 to 1,500 miles

from the continental United States in the North

Atlantic or Gulf of Alaska. The concept as used

by OTA differs in several respects to the

“small sub underwater mobile” (SUM) basing

concept advanced by Sidney Drell and Richard

Garwin.

Smallsub Underwater Mobile (SUM) Basing: A concept

for the deployment of MX missiles on small submarines proposed by Sidney Drell and Richard

Garwin.

Split Basing: As used in this report, split basing refers

to the construction of multiple protective

shelters for the MX missile in two regions of

deployment. One half of the MX force would be

deployed in portions of Texas and New Mexico

and the other half of the force would be

deployed in Nevada and Utah.

Sprint: A very high acceleration, nuclear-armed

endoatmospheric ABM interceptor missile deployed by the United States in the early 1970’s

as part of the SAFEGUARD ABM system.

SSBN: Designator of nuclear-powered, fleet

ballistic, missile-carrying submarines deployed

by the United States, the Soviet Union, France,

and the United Kingdom.
App. C—Acronyms and Glossary ● 335

Star Tracker: A device carried aboard a ballistic

missile used to obtain information on the position and orientation of the missile in relationship to a known star for purposes of improving

in-flight guidance and the accuracy with which

a reentry vehicle could be delivered against a

target.

Strategic Triad: The three different types of platforms used by the United States to deliver

strategic nuclear weapons: ICBMS, submarines

carrying SLBMS, and bombers carrying gravity

bombs, short-range attack missiles, and longrange air-launched cruise miss iles.

Submarine-launched Ballistic Missile (SLBM): A ballistic missile carried in or attached to and

launched from a submarine.

SUM: An acronym for Smallsub Underwater Mobile

basing for MX proposed by Sidney Drell and

Richard Garwin,

Transporter-Erector-launcher (TEL): A vehicle designed for an earlier version of MPS basing

which would have been used to transport the

MX missile, erect it to a vertical position, and

then launch it.

Time-on-Target Control: The ability to control the

time at which several nuclear weapons arrive at

a particular target.

Transattack: The period of time in which the United

States and the Soviet Union are actively engaged in the exchange of nuclear weapons. This

can be a period of minutes or can extend for

hours or even days,

Transporte~ A vehicle designed to transport the MX

missile or a mass simulator, and to perform an

exchange of either missiIe or the mass simuIator

and a protective shelter.

Trident Missile: A modern submarine launched

ballistic missile deployed by the United States.

The Trident I missile is currently being produced and deployed; the Trident I I would be a

larger and more accurate missile proposed for

initial deployment in the late 1980’s.

Trident Submarine: A very large nuclear-powered,

ballistic missile-carrying submarine being

deployed by the United States.

Valley Cluster Basing: A variant of MPS basing for

the MX missile in which missiles may be moved

freely among the protective shelters in an entire

valIey as opposed to onIy within a cluster.

Vertical Shelters: Protective shelters for the MX or

Minuteman missile resembling ICBM silos,

housing the missile and its mobile launch support equipment in a vertical position.

Warning Systems: Satellites, ground-based radars,

and other mobile sensors used to provide the

United States warning of an impending ICBM,

SLBM, or bomber attack.

Yield: The energy released in an explosion. The

energy released in the detonation of a nuclear

weapon is generally measured in terms of the

kilotons or megatons of TNT required to produce the same energy release.

o