BACKGROUND PAPER

U.S. Airlift Forces:

Enhancement Alternatives for

NATO and Non-NATO Contingencies

April 1979

Congress of the United States

Congressional Budget Office
U.S. AIRLIFT FORCES:

ENHANCEMENT ALTERNATIVES FOR NATO

AND NON-NATO CONTINGENCIES

The Congress of the United States

Congressional Budget Office

For sale by the Superintendent of Documents, U.S. Government Printing Office

Washington, D.C. 20402

PREFACE

The U.S. government owns and maintains a large fleet of

military cargo planes. These transports are essential for almost

every possible contingency involving U.S. ground forces—from a

major reinforcement of NATO in a war with the Warsaw Pact to the

deployment of small fighting units to remote locations. The

Department of Defense has given major attention in recent years to

programs that would improve the current capability of airlift

forces. This year the Congress faces critical decisions on almost

all of these airlift improvement programs. This paper, prepared

at the request of the Senate Committee on the Budget, examines the

current airlift system and the improvement programs before the

Congress this year. It evaluates the improvement programs in

terms of their contribution to airlift operations in NATO and

non-NATO contingencies. In accordance with CBO's mandate to

provide objective analysis, this paper offers no recommendations.

The paper was prepared by John J. Harare of the National

Security and International Affairs Division of the Congressional

Budget Office, under the general supervision of David S.C. Chu and

Dov S. Zakheim. Helpful comments on earlier drafts were provided

by Richard B. Rainey, Jr., of the Pan Heuristics Corporation and

by Pat Hillier, Marshall Hoyler, C.R. Neu, and Larry Oppenheimer

of the CBO staff. (The assistance of external reviewers implies

no responsibility for the final product, which rests solely with

the Congressional Budget Office.) Edward Swoboda of CBO's Budget

Analysis Division prepared the cost estimates. The author gratefully acknowledges the contribution of Nancy Swope, who coordinated production of the paper, and Harold Furchtgott, who

provided technical assistance. Patricia H. Johnston edited the

paper; Janet Stafford prepared the manuscript for publication.

Alice M. Rivlin

Director

April 1979

iii

CONTENTS

PREFACE , iii

SUMMARY xi

CHAPTER I. INTRODUCTION 1

Requirements for Airlift Improvement 3

Purpose of This Study 6

CHAPTER II. THE AIRLIFT SYSTEM 7

Basic Features of the Airlift System ..... 7

Airlift Operations and the

Airlift System 13

CHAPTER III. OPERATIONAL PERFORMANCE OF THE

AIRLIFT SYSTEM 19

Capabilities of the Current

Airlift System 19

The Effect of Enhancement Programs

on Airlift Performance 26

CHAPTER IV. ALTERNATIVE AIRLIFT FORCES FOR

THE FUTURE 47

Airlift in a NATO/Warsaw Pact War 47

Airlift in a Middle East/

Persian Gulf Contingency 54

Alternative Airlift Forces

for the Future 58

Summary 65

APPENDIX A. ASSUMPTIONS AND METHODOLOGY USED

IN AIRLIFT CALCULATIONS 69

TABLES

TABLE 1. ANNUAL SQUADRON OPERATING COSTS

AT CURRENT MANNING AND ALL

ACTIVE-DUTY MANNING 12

TABLE 2. STRATEGIC AND TACTICAL AIRCRAFT

PERFORMANCE DATA 15

TABLE 3. PROGRAMMED AIRLIFT CAPABILITIES

BY TYPE OF AIRCRAFT 20

TABLE 4. ESTIMATED AIRLIFT REQUIREMENTS

BY TYPE OF DIVISION 20

TABLE 5. AVERAGE PAYLOADS FOR ORGANIC

AND CIVILIAN RESERVE PLANES 22

TABLE 6. AIRLIFT PERFORMANCE AT FULL

AND REDUCED SYSTEM OPERATIONS 25

TABLE 7. CLOSURE TIME AS A FUNCTION

OF C-5 AVAILABILITY 27

TABLE 8. AN OVERVIEW OF OPTIONS FOR

EXTENDING THE SAFE SERVICE

LIFE OF THE C-5 WING 30

TABLE 9. AIRLIFT ENHANCEMENT: EFFECTS

OF C-141 STRETCH VS. GRAF

MODIFICATION PROGRAMS 34

TABLE 10. CLOSURE TIMES AS A FUNCTION

OF TACTICAL TRANSPORT

AUGMENTATION 44

TABLE 11. TIME REQUIRED TO DELIVER FIVE MECHANIZED

DIVISIONS AND 55 TACTICAL FIGHTER

SQUADRONS TO EUROPE, ASSUMING DIFFERING

LEVELS OF PRE-POSITIONED EQUIPMENT 49

vii

TABLES (Continued)

TABLE 12. CURRENT AND IMPROVED TACTICAL

TRANSPORT CONTRIBUTION TO THE TIME

REQUIRED TO DELIVER FIVE DIVISIONS

AND 55 TACTICAL FIGHTER SQUADRONS

TO EUROPE, ASSUMING DIFFERING LEVELS

OF PRE-POSITIONED EQUIPMENT 53

TABLE 13. TIME REQUIRED TO DELIVER COMBAT

UNITS TO THE PERSIAN GULF AREA

WITH VARYING AIRLIFT RESOURCES,

BY TYPE OF DIVISION 55

TABLE 14. IMPROVED DELIVERY RATES TO PERSIAN

GULF WITH AMSTs OR ADDITIONAL C-5s,

BY TYPE OF DIVISION 57

TABLE 15. ALTERNATIVE AIRLIFT FORCES FOR

THE FUTURE 66

TABLE A-l. AIRCRAFT VARIABLES USED IN

COMPUTATION OF AIRLIFT CAPACITY 70

TABLE A-2. UNIT EQUIPMENT AND SUPPORT CARGO,

BY TYPE OF DIVISION 74

TABLE A-3. PAYLOAD PLANNING VARIABLES USED

IN AIRLIFT COMPUTATIONS 76

FIGURE 1. DELIVERY TIME AS A FUNCTION

OF DISTANCE, BY TYPE OF DIVISION 23

FIGURE

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43-168 O - 79 - 2

SUMMARY

The U.S. government owns and maintains a large fleet of

specially designed military cargo planes. These transports are

essential for almost every possible contingency involving U.S.

ground forces—from a major reinforcement of NATO in a war with

the Warsaw Pact to the deployment of small fighting units to

remote locations to support friendly nations. The Department of

Defense (DoD) has given much attention in recent years to programs

that would improve the current capability of airlift forces. This

year the Congress faces critical decisions on almost all of these

airlift improvement programs. The 1980 budget provides for

the following changes to the strategic (intertheater) airlift

fleet:

o Initial procurement of components for a new wing for the

C-5 transport. This program could eventually lead to

modification of the entire fleet of C-5 aircraft, at an

estimated cost of $1.1 billion.

o The start of a major program to modify new civilian

passenger aircraft at government expense to enable them

to carry military cargo in an emergency. This year DoD

proposes to modify nine commercial aircraft, at a cost of

$91 million. It proposes eventually to modify more than

65 aircraft under this program.

o Continued procurement of a new advanced tanker/cargo

aircraft, the KC-10. Two of these aircraft were authorized last year, and four have been requested in the fiscal

year 1980 budget, at a cost of $190.1 million. Eventually, DoD proposes to purchase a fleet of 20 KC-10s,

with total program costs expected to reach $1 billion.

o Continued modification of the C-141 military transport. This program involves "stretching" the C-141

by installing additional sections of fuselage in order

to increase its potential payloads. The fiscal year 1980

budget includes $130 million for this program.

In addition, one program concerning tactical (intratheater)

airlift will be considered:

xi
o Continued evaluation, at limited funding, of an advanced

tactical transport. Although the Air Force had proposed

to replace the current fleet of C-130s with a new transport, the AMST, the Department of Defense has decided

not to purchase this plane. The Congress must decide if

it wants to pursue development of a replacement aircraft

for the C-130 and, if so, at what pace.

Though many of these airlift enhancement programs were

initially proposed in 1974, their implementation has been delayed,

in large measure because of questions raised by the Congress.

In choosing among the contending alternatives, the Congress

faces two primary issues:

o What types of contingency requirements should guide

airlift improvement, and what amount of enhancement is

needed?

o If not all programs are necessary, do some have advantages

over the others?

Answers to these questions depend on an analysis of the structure

of the current airlift system and its ability to meet anticipated

airlift requirements in the future.

STRUCTURE OF THE AIRLIFT SYSTEM

The airlift system is characterized by a distinction between

organic transports (planes owned and operated by the U.S. Air

Force) and civilian reserve aircraft under the CRAF program

(commercially owned planes that would be used to transport military cargo and personnel during time of war). Currently, organic

transports and civilian reserve aircraft make roughly equal

contributions to airlift capacity. Each component has its respective advantages and limitations.

Organic Transports

The principal advantage of the organic component is its

flexibility. Organic aircraft are immediately available at the

direction of the President to respond in emergencies. They are

specially designed to operate in rugged areas under combat conditions. They are built specifically to carry military cargo and

small numbers of troops who would operate the equipment upon

XII
arrival. Government ownership of those planes permits continual

training of air and ground crews so that they can function effectively in emergency and combat situations.

The primary disadvantage of organic assets is their expense.

The existing fleet of intertheater airlift transports—C-5s

and C-141s—cost $5.9 billion to procure. Annual operation and

maintenance costs for the fleet exceed $1.1 billion.

Civilian Reserve Augmentation

The primary advantage of civilian aircraft augmentation

is that it does not incur costs to the government during peacetime. Civilian reserve aircraft would be an effective supplement to organic assets during wartime, available at almost

no cost to the federal government. Also, when activated, civilian airlift costs less to operate than comparable military air

transportation.

The primary disadvantage of civilian reserve augmentation is its inflexibility. In fact, at no time in the 25-year

history of the program have civilian reserve assets been mobilized, even at the lowest level of mobilization. Mobilization of commercial planes could be very disruptive to the

domestic economy. It could also send important, and perhaps

undesirable, signals to both allies and potential adversaries.

Further, commercial planes cannot operate under the potentially

restrictive conditions (small, rough airfields, for example)

that can routinely be handled by military cargo planes. Moreover, airline companies might be hesitant to commit planes to

military operations if they feared their future commercial

relations with other countries might be jeopardized or if they

felt their routine domestic business would be disrupted too

severely.

AIRLIFT OPERATIONS IN NATO AND NON-NATO CONTINGENCIES

Requirements for airlift capabilities depend upon the

nature of contingencies for which airlift is demanded. Current

DoD planning focuses on two types of contingencies as part of the

"one-and-one-half war" strategy: a major NATO/Warsaw Pact conflict centered in Europe and a lesser contingency occurring

simultaneously elsewhere, notably the Middle East or the Persian

Gulf region. These contingencies vary in their requirements for

xiii
airlift support. Choices among alternative airlift improvement

programs will, therefore, be affected by which contingency is

emphasized when formulating airlift needs.

Airlift in a NATO/Warsaw Pact War: What Amount of Improvement Is

Needed?

Reinforcement objectives currently outlined by DoD call for

the delivery of an equivalent of five divisions to Europe within

ten days of mobilization, as well as some 1,300 tactical fighter

aircraft within a week. These objectives could not be met by

airlift forces alone, even with implementation of the enhancement

programs noted above. Meeting these objectives would depend on

the pre-positioning of combat equipment in Europe for U.S. ground

force units that would deploy there in time of war. Airlift

resources would then be free to move troops, residual cargo,

Marine units, and tactical fighter squadrons upon mobilization.

If equipment was pre-positioned for all divisions and support

units expected to be in Europe at the outbreak of war, current

airlift resources might be able to satisfy reinforcement objectives, so that further airlift enhancement might not be necessary.

Other delivery objectives (those relating to tactical fighter

squadrons, for example) might not be met without airlift enhancement. Yet the programs pending before the Congress would improve

delivery rates by only a few days. Moreover, alternatives other

than airlift, such as pre-positioning more Air Force support

equipment, might be considered. Therefore, the additional

capability that these airlift improvements would provide might not

be commensurate with their cost. Tactical airlift requirements,

if considered in the context of a NATO war, also do not appear to

justify procurement of a new fleet of tactical transports.

Airlift in a Limited Contingency: What Amount of Improvement

Is Needed?

There are no formal delivery objectives for a limited

contingency, comparable to those for a NATO conflict, against

which the adequacy of the existing airlift fleet and requirements

for enhancement can be easily measured . This study examines

requirements that might be associated with the deployment of

two divisions to the Persian Gulf area. This contingency was

chosen because it presents a demanding deployment objective and

parallels current Department of Defense planning. Assuming full

xiv
availability of existing airlift resources, including GRAF, as

many as five weeks might be required to deploy a two-division

force to the Persian Gulf region, although smaller elements

of the force could be delivered within a few days. Airlift

improvement programs (GRAF modification and the C-141 stretch)

could potentially reduce delivery time by as much as 20 percent

for lighter divisions and by a smaller percentage for heavier

un i t s .

Potentially serious constraints on existing airlift resources could substantially prolong delivery of forces in a

limited contingency. It is uncertain that the GRAF fleet would

be fully activated in a limited contingency, though some civilian augmentation could be expected. Programs that increase

the capacity of organic transports would compensate for the

possible lack of available civilian reserve assets, thus improving

the capability of airlift forces to meet limited contingency

objectives.

Requirements for tactical airlift in a limited contingency

could potentially justify procurement of an advanced tactical

transport, such as the AMST. Tactical airlift could be particularly valuable in non-European areas, which lack the sophisticated

ground transportation network of Western Europe.

ALTERNATIVE AIRLIFT FORCES FOR THE FUTURE

Airlift forces are a vital component of the U.S. conventional

force structure. They are also an expensive component. In

choosing among the airlift enhancement programs proposed in the

fiscal year 1980 budget, the Congress may wish to evaluate the

programs in terms of alternative assumptions about future airlift

requirements.

Airlift Improvements to Meet NATO Reinforcement Objectives

The Congress may determine that NATO reinforcement should

be the primary planning objective for airlift improvement.

Several current reinforcement objectives can largely be met with

existing resources, assuming continuation of the program to preposition equipment in Europe for combat troops. Other delivery

objectives that cannot be met at this time could be met with

improved airlift. They could also potentially be met by other

alternatives, such as further pre-positioning of equipment for

xv
support units. Therefore, significant expenditures on airlift

enhancement might not be necessary at this time.

Only modest funding might be needed for other airlift enhancement programs. In particular, the GRAF modification program

might not be necessary. The C-5 must be retained in the fleet,

though a more limited wing modification program than is currently

being proposed by the Department of Defense could be sufficient.

The C-141 stretch program has progressed to the point that termination at this time would probably not produce substantial savings. Tactical airlift modernization could be limited to replacement of older C-130s with newer models. Restricted to these

programs, airlift improvements would cost approximately $422

million in fiscal year 1980 and $2.9 billion to complete the total

program.

Airlift Improvements to Meet Limited Contingency Objectives

Alternatively, the Congress may determine that airlift

programs should improve the ability of the current system to

meet the demands of a limited contingency operation. It could

then select improvement programs that enhance the inherent flexibility of the existing organic system. Such programs could

include a full wing modification of the C-5, completion of the

C-141 alteration program, and replacement of older model C-130s

with newer models. These improvement programs would cost $423

million in fiscal year 1980 and $3.5 billion to complete the

program. They would not substantially alter delivery rates. They

would, however, improve the flexibility of existing organic

resources.

An Expanded Airlift System for Limited Contingencies

The Congress might also choose to expand current airlift

forces, judging that current resources—even with the improvements outlined above—would be inadequate to meet the demands of

limited contingencies. Two substantially different alternatives

are available:

o The Congress could choose to improve strategic deployment capabilities by procuring additional outsize transports such as the C-5. Procurement of 50 C-5s would cost

$4.6 billion.

xvi
o Alternatively, the Congress could choose to improve

tactical airlift capabilities, replacing existing C-130s

with the AMST. The primary contribution of tactical

airlift modernization would be to improve capabilities to

reposition units within a theater, though some modest

improvement in deployment rates could be expected as well.

Procurement costs for a fleet of 277 AMSTs could reach

$8.3 billion.

CONCLUSIONS

The Congress must make several important decisions this

year concerning airlift resources. The budgetary effect of these

decisions will be substantial and immediate, as shown in the

following table. These decisions will also determine the structure and capabilities of airlift forces in future years.

Requirements for airlift capabilities and choices among

airlift improvement programs depend upon the nature of contingencies for which airlift is needed. The Congress can choose to

emphasize NATO reinforcement objectives and thereby avoid substantial budgetary costs associated with the fiscal year 1980

budget. Such a decision, however, would limit the flexibility of

airlift forces in the future. Alternatively, the Congress can

authorize funds for improvements to the current airlift system to

make it more responsive to non-NATO contingencies. In doing so,

the flexibility of existing airlift forces would be increased, but

at substantially increased costs.

xvii

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ALTERNATIVE AIRLIFT FORCES FOR THE FUTURE: IN MILLIONS OF FISCAL YEAR 1980

DOLLARS

Fiscal Total Program Costs

Year (Fiscal Year 1980

Alternative Airlift Forces 1980 and Beyond)

Department of Defense Program Baseline a/

Full wing modification of C-5s 91

CRAF modification program 74

C-141 stretch program 130

KC-10 Advanced Tanker/Cargo Aircraft 190

Replace 208 C-130 models A/B/D with model H 202

Total, DoD Baseline 687 4,760

NATO Reinforcement Airlift Force

Fastener change on existing C-5s 90 543

Replace 208 C-130 models A/B/D with model H 202 2,096

Continue C-141 stretch program 130 269

Total, NATO Reinforcement 422 2,908

Limited Contingency Airlift Force

Full wing modification of C-5s 91 1,087

Replace 208 C-130 models A/B/D with model H 202 2,096

Continue C-141 stretch program 130 269

Total, Limited Contingency 423 3,452

Expanded Airlift Force

Enhanced strategic airlift force

Procurement of 50 new C-5s 30 4,604

Fastener change on existing C-5s 90 543

Replace 208 C-130 models A/B/D with model H 202 2,096

Continue C-141 stretch program 130 269

Total, Enhanced Strategic 452 7,512

Enhanced tactical airlift force

Procurement of 277 AMSTs 5 8,256

Full wing modification of C-5s 91 1,087

Continue C-141 stretch program 130 269

Total, Enhanced Tactical 226 9,612

a/ The Department of Defense baseline includes those programs listed in the

fiscal year 1980 posture statement. Since DoD has no current plans for

tactical airlift modernization, CBO has selected the least expensive option

(that is, replacement of 208 C-130 models A/B/D with new model H) for inclusion in the baseline airlift force.
CHAPTER I. INTRODUCTION

The United States government owns and operates the largest

fleet of transport airplanes in the western world. Consisting

of more than 900 aircraft, the fleet is managed principally

by the Military Airlift Command (MAC) of the U.S. Air Force.

Military airlift forces permit the rapid delivery of U.S. combat

forces in a wide range of potential emergencies.

To enhance the capability of airlift mobility forces,

in 1974 the Secretary of Defense proposed a major program of

airlift improvements. The Congress has raised questions about

portions of this program; _!/ consequently, many of the proposals remain active budgetary issues today. In considering

the fiscal year 1980 budget, the Congress will be asked to

decide on the following airlift enhancement proposals:

o Continued development and initial production of a new

wing for the C-5 military transport.

o Continued procurement and installation of airframe sections to lengthen the fuselage of the C-141 transport.

o Installation of cargo features in new civilian passenger

aircraft.

_!/ In 1976, the Senate Committee on Armed Services, concerned

with the apparent lack of coordination in planning of mobility

programs, directed the Department of Defense to undertake

a thorough review of mobility requirements and operations.

At approximately the same time, the General Accounting Office

suggested a framework for evaluating strategic airlift. As a

consequence, the Joint Chiefs of Staff were commissioned to

conduct a study on mobility requirements and programs. An

unclassified summary of that study may be found in The

Posture of the U.S. Military Airlift, Hearings before the

House Committee on Armed Services, 95:1 (September 1977),

pp. 25-44.
o Procurement of four additional DC-lOs, modified to function as tankers.

o Development of a new tactical aircraft capable of landing

on very short and rough fields under combat conditions.

C-5 Wing Modification. The C-5 "re-wing" program is intended

to extend the plane's currently projected service life to the

original 30,000-hour goal. The fiscal year 1980 budget provides

$12.7 million in continued development funds and $78.6 million for

initial production of wing components for seven planes. Total

program costs are estimated to reach $1.1 billion ($1.3 billion in

current year dollars) by fiscal year 1986. 2J The Congress must

decide this year whether to proceed with the re-winging program as

proposed by the Department of Defense (DoD) or to pursue instead a

less extensive, and less costly, modification.

C-141 "Stretch" Program. The C-141 "stretch" program, which

also includes installation of aerial refueling equipment, will

increase the plane's potential cargo capacity by as much as 30

percent. The fiscal years 1978 and 1979 budgets provided funds

for modification of 17 planes. The fiscal year 1980 budget

proposes to modify an additional 65 planes, at an estimated cost

of $130 million. Unlike other enhancement alternatives, most of

which are still in the initial development or procurement stage,

the C-141 stretch program is substantially underway. The Congress

will be asked to decide this year whether to extend the modification to the remaining 255 of the fleet of 272 C-141s at a cost

of $269 million.

GRAF Modifications. This program would increase the amount

of cargo capacity in the civilian sector that could be marshalled

for military operations in a national emergency. The fiscal year

1980 budget includes $73.6 million for the installation of cargo

features in nine new passenger planes. DoD proposes ultimately to

modify at least 65 new planes over the next five years. The

Congress authorized funding for a pilot program last year; it must

now decide whether or not to proceed in full with the modification

program.

2/ All cost figures presented in this paper are in fiscal year

1980 dollars, unless otherwise specified.
Advanced Tanker/Cargo Aircraft. The fiscal year 1980 budget

provides $190.1 million for procurement of four DC-lOs, which

will be modified to function as tankers. Funds for procurement of the first two such planes—designated the KC-10—were

authorized in the fiscal year 1979 budget. The total program

cost for the proposed remaining fleet of 18 KC-10 tankers would

exceed $750 million. Since the program is still in its initial

stages, the Congress must decide this year whether to continue

procurement and, if so, at what pace.

Tactical Airlift Modernization. A new tactical transport

(AMST), capable of landing in very short and rough fields under

combat conditions, has been under development for several years.

Although the President recommended against procurement two years

ago, the question of tactical airlift modernization has persisted.

The Air Force is expected to decide between two prototypes this

summer, and $5 million has been set aside in the fiscal year 1980

budget for the program. The Congress has an opportunity to decide

this year whether to continue the advanced tactical transport

program beyond the prototype competition stage. Procurement costs

for 277 of these planes could potentially reach $8.3 billion.

If the Congress decides not to pursue AMST procurement, it must

determine the pace at which older tactical transports should be

replaced.

REQUIREMENTS FOR AIRLIFT IMPROVEMENT

Requirements to improve airlift mobility forces are based on

their potential use in two possible contingencies: a NATO/Warsaw

Pact conflict and a limited contingency occurring elsewhere.

Requirement to Reinforce NATO

Airlift improvement programs have traditionally been justified on the basis of the need to reinforce American ground forces

deployed in Europe in the event of a Warsaw Pact attack against

NATO. Modernization of Soviet ground forces in Eastern Europe in

recent years has led defense planners to conclude that the Warsaw

Pact would be able to mobilize and launch a massive attack in

Europe in a much shorter period than previously believed. 3_/

3_l See Congressional Budget Office, Assessing the NATO/Warsaw

Pact Military Balance, Budget Issue Paper (December 1977),

especially pp. 20-21.
Under such a short-warning scenario, military airlift would play a

crucial role in delivering U.S. reinforcements to NATO.

The current reinforcement objective of DoD mobility programs is to enable the doubling of U.S. ground forces currently

deployed in Europe in about 10 days and the delivery of more

than 1,300 tactical fighters within one week, kj The first

objective would involve transporting approximately five divisions, currentl y based in the United States, to Europe . The

only program now underway that can satisfy this requirement

involves the advanced positioning of combat equipment in Europe for U.S.-based troops who would deploy there in time of

war. _5/ Equipment for approximately two divisions is presently

stored in Europe ; the Departmen t of Defense has proposed to

pre-position equipment for an additional three divisions over

the next several years. With advanced positioning of equipment, airlift forces would be used only to transport troops and

the small proportion of division equipmen t that will not be

pre-positioned.

Without pre-positioning equipment, DoD's NATO reinforcement

objectives could not be met, even with the airlift enhancement

programs noted above. If, on the other hand, equipment fo r

five divisions was pre-positioned in Europe, as proposed by DoD,

the current airlift system—without the enhancement programs—

could meet the 10-day delivery requirement for ground combat

units. 6_/ Without airlift enhancement, however, some tactical

fighter squadrons would arrive several days after their desired

delivery, as would some support units for ground combat forces.

There are alternatives to airlift improvement, however, that might

allow these objectives to be met. Further, it should be noted

that the delivery schedules are planning objectives that are

subject to evaluation as well.

4/ U.S. Department of Defense, Annual Report, Fiscal Year 1978,

p. 201.

_5/ The advanced positioning of combat equipment in Europe is

discussed in Congressional Budget Office , Strengthening NATO:

POMCUS and Other Approaches, Background Paper (February

1979).

_§/ This questio n is discussed at greater length in Chapter

IV.
If NATO reinforcement is judged to be the primary requirement

for which airlift forces are improved, it is questionable whether

all of the programs envisioned under the enhancement program are

necessary.

Mobility Requirements in Limited Contingencies

While NATO reinforcement has dominated defense planning of

mobility forces in recent years, the primary advantage of airlift

is its ability to respond to a broad range of circumstances in

virtually any location. This capability has been appreciated by

every President since the end of World War II, and airlift forces

have been a critical element in many operations during this

period. _7_/ Indeed, if American forces were required to assist in

the defense of South Korea, or were to be deployed to the Middle

East or Persian Gulf areas to aid a friendly country, airlift

forces would be indispensible. _8_/

These projected limited contingencies place different,

and in some instances greater, demands on airlift forces than

does the reinforcement of NATO. For example, equipment for

U.S. ground forces is pre-positioned only in Europe. In the

event of a contingency elsewhere in the world, deployment of

combat forces would require that equipment as well as troops

be airlifted. While current airlift forces are capable of carrying out such an operation, it is uncertain whether all elements

of the airlift system would be available in a limited contingency. The current airlift system relies heavily on commercial

transports to supplement military operations. Civilian augmentation is questionable in limited contingencies. Airlift

improvements could be made that would help overcome that limitation, however.

7J Few of these operations have been taxing. The Military

Airlift Command was called upon to deliver emergency supplies

to Israel in 1973, to evacuate Americans and Vietnamese

from Southeast Asia in 1975, and to deliver goods and combat

troops to the Shaba province in Zaire in 1977 and 1978.

"Humanitarian" missions, such as the evacuation of American

dead from Jonestown, Guyana, are more recurrent, though less

demanding.

_§/ U.S. Department of Defense, Annual Report, Fiscal Year 1980,

p. 202.
PURPOSE OF THIS STUDY

The two types of contingencies discussed above suggest

different goals for airlift improvement. If NATO reinforcement

is judged to be the primary requirement for which airlift forces

are structured, the objective of an airlift improvement program

would be to store, as inexpensively as possible, wartime airlift

capacity. If, on the other hand, airlift improvements are intended to strengthen U.S. capability to meet limited contingencies, wartime flexibility should be the primary goal of an improvement program.

A number of airlift improvement proposals will be considered

by the Congress this year. Decisions on these programs will

substantially affect the nature of airlift forces in the future

and their ability to respond to future requirements. In choosing

among contending alternatives, the Congress will have to examine

two primary questions:

o What types of contingency requirements should guide airlift improvement, and what amount of enhancement is

needed?

o What margin of flexibility should be maintained in the

future airlift system to meet those requirements?

This paper examines the current airlift mobility system in

terms of those factors that have relevance for upcoming decisions

on airlift improvement programs. Chapter II describes the current

airlift system in terms of its components and types of missions.

Chapter III examines the system in terms of its performance.

Specific attention is given to the effect of each of the improvement programs on performance, as well as to the advantages

and disadvantages of each enhancement program. Chapter IV examines the major types of airlift contingencies that could be used

to evaluate the need for and extent of airlift improvement. The

chapter concludes by considering several alternative airlift

improvement programs.
CHAPTER II. THE AIRLIFT SYSTEM

This chapter introduces and analyzes the basic features of

the structure of U.S. airlift mobility forces. The chapter begins

with a description of the components of the existing airlift system. It then outlines the mission requirements of airlift forces

and examines the factors that affect their operation.

BASIC FEATURES OF THE AIRLIFT SYSTEM

The features of the U.S. airlift system parallel and reflect

the basic determinants of defense planning in the post-World

War II period. Defense planning is dominated by the prospect of

war with the Soviet Union, either in a strategic nuclear conflict

or in a conventional war between NATO and Warsaw Pact forces in

Central Europe. The magnitude of Soviet military capability

imposes tremendous pressure to increase U.S. defense capabilities.

A strong national defense, it is argued, will serve to deter

Soviet aggression.

Defense spending reflects the tension between providing

military resources sufficient to deter Soviet aggression while

keeping American defense expenditures as small as possible. The

pressure to find less expensive ways to store war-fighting

capacity during peacetime has only been amplified in recent

years by the massive and continuing modernization of Soviet

conventional forces. The structure of the U.S. airlift system—

particularly the distinction between organic and civilian reserve

aircraft and between active-duty and reserve manpower—reflects

this dual objective of improving war-fighting capability while

minimizing annual peacetime operating costs.

Organic Transports vs. Civilian Reserve Aircraft

The U.S. airlift system consists of two distinct components:

(1) planes owned and operated by the U.S. government and managed

by the Military Airlift Command and the Air National Guard

(organic airlift transports); and (2) commercially owned jet aircraft which, during time of war, could be used to augment organic

resources. The commercial planes are organized into the Civil

43-168 O - 79 - 4
Reserve Air Fleet (CRAF), _!/ created in 1951 by executive order

to meet emergency airlift requirements in excess of MAC organic

capability. The primary advantage of civilian reserve aircraft

is that they can provide an effective supplement to organic

airlift at almost no peacetime cost. When activated, CRAF costs

less than comparable military air transportation. Commercial

airlines have subscribed 262 passenger planes and 113 cargo planes

to the CRAF program. These are long-range aircraft that would be

assigned to augment organic military assets in intertheater

airlift operations. 2J CRAF planes are mobilized in three stages.

Stage I can be activated by the Commander of MAC and currently

consists of about 15 percent of all planes in the CRAF program.

Stage II is activated by the Secretary of Defense to provide airlift capability for a major contingency requirement not warranting

national mobilization. Full mobilization of CRAF—Stage III—is

activated only after a national emergency is declared by the

President or the Congress.

As late as 1970, the Department of Defense contended that

CRAF "cannot be used in the combat airlift role." The primary

mission assigned to CRAF was the replacement of long-range military airlift capability withdrawn from worldwide logistics operations to support specific deployment emergencies. _3/ By contrast,

current DoD mobility studies envision full CRAF participation

Tj The CRAF program is but one of three programs planning for

the use of civilian airplanes during wartime. The Civil

Aeronautics Board (CAB) manages the War Air Services Program

(WASP); the Federal Aviation Administration (FAA) oversees

the State and Regional Defense Airlift (SARDA) plan. These

two programs are intended to provide a means of controlling

airlift assets during wartime to meet priority domestic

requirements. The SARDA plan affects small planes in civil

aviation; the WASP program includes all CAB-licensed planes

not assigned to the CRAF program.

2J An additional 95 planes in the CRAF fleet would be assigned

to domestic and short-range international missions, such

as supplying forces in Alaska. These planes are intended

to assume routine domestic supply operations during wartime.

.3/ Military Airlift, Hearings before the Subcommittee on Military

Airlift, House Committee on Armed Services, 91:2 (January and

February 1970), p. 6284.
in airlift operations in a NATO war. 47 This reflects the increasingly important contribution of GRAF as a source of emergency

airlift capacity.

By way of contrast, the MAC organic fleet consists of 353

long-range airplanes—77 C-5 Galaxies and 276 C-141 Starlifters—

that are designed specifically to operate in a broad range of

potential situations, including hostile conditions. _5/ Organic

transport aircraft are expensive to procure and operate. There

are two components to the costs of organic airplanes. One involves the performance penalties associated with aircraft designed

for military operations. Because of their unique design features

and extra weight, their operating expenses are approximately 14

percent higher than those of commercial planes. 6f

Far larger is the cost associated with owning organic aircraft, regardless of airplane design. Acquisition of the current

fleet of C-5s and C-l41s cost $5.9 billion in then year dollars

and $12.8 billion in fiscal year 1980 dollars. Annual operating

expenditures exceed $1.1 billion. To minimize operating costs,

the C-5 and C-141 are flown only at rates necessary to meet

4_/ See written statement of General William G. Moore in The

Posture of the U.S. Military Airlift, Hearings before the

House Committee on Armed Services, 95:1 (September 1977),

p. 11.

_5_/ Organic airlift assets are designed to operate in rough areas

under combat conditions and share similar design characteristics. The cargo floor is at the bottom of the plane (rather

than in the middle, as is the case with civilian jetliners) to

facilitate loading and unloading. The wings are at: the top of

the fuselage, and the tail is swept up so that cargo can be

loaded through a rear drive-in door and ramp. This also makes

it possible to parachute cargo from the plane so that the

aircraft need not land in hostile territory. Landing gear of

organic transports is sturdier than comparable civilian

equipment.

_6_/ For example, the C-5 carries approximately 40,000 pounds of

dead weight caused by its sturdier landing gear, reinforced

floors, built-in cargo handling systems, and so on. Also,

the wing design of the C-5 forces it to fly at a slightly

lower cruising speed than comparable commercial aircraft.
minimum requirements for air crew training and proficiency.

Currently, the C-5 averages a 1.8-hour utilization rate per day ]_/

and the C-141, 3.23 hours per day.

Organic transports have many advantages over civilian reserve

planes. They are designed to carry virtually the full inventory

of military cargo, including many items too large or too heavy

for commercial transports. _8/ Military transports have built-in

cargo handling equipment and, unlike commercial freighters,

are not restricted to airports with such equipment in place. 9/

Organic assets also provide greater certainty in planning.

Their availability in a national emergency is assured, and

they can respond to DoD direction without significantly disrupting the civilian economy. Similarly, detailed loading plans

can be developed and rehearsed. Since only a small portion

of the cargo airlifted in time of war will be on pallets, 10/

familiarity with Army equipment and loading configurations is

necessary for efficient wartime operations.

7/ A utilization rate is a planning concept that reduces airplane operating rates, on a system-wide basis, to a single

figure, expressed in terms of daily flying hours. Three

factors largely determine the utilization rate: the number

of air crews, the number of maintenance crews, and the

availability of spare parts. The utilization rate thus

expresses system-wide performance, subsuming in the figure

the many complex factors that affect a plane's performance at

any one time.

JJ/ Substantial modification of the B-747 would be required,

for example, to enable it to carry the main battle tank—

the M-60—or the new XM-1. The plane's flight deck would

have to be raised in order to accommodate a larger nose door.

See The Posture of Military Airlift, Hearings before the

Subcommittee on Research and Development, House Committee on

Armed Services, 94:1 (November 1975), pp. 335-36.

_9_/ Special equipment is needed to elevate cargo for loading onto

commercial transports. The cargo floor of a military transport can be as low as five feet off the runway, whereas a

B-747's cargo floor is 16 feet from the ground.

10/ Bulk cargo is generally loaded on pallets, which are in turn

loaded on planes by fork-lift trucks.

10
Besides lacking the design advantages of military transports,

civilian reserve planes have other significant disadvantages.

Mobilization of the CRAF fleet could be disruptive to the domestic

economy—acceptable, perhaps, only in the event of a substantial

national emergency, ll/ Mobilization could also send important,

and perhaps undesirable, signals both to allies and to potential

adversaries that might exacerbate international tension and,

perhaps, even lead to preemptive military action. Equally important, airline companies might be reluctant to commit planes

to military operations if they feared their future commercial

relations with other countries could be jeopardized or if they

felt their routine business would be disrupted too severely. 12/

The division of military airlift into organic and civilian

reserve assets has evolved over the years and has become a central

feature of the airlift system. As will be seen, it has direct

relevance to the range of potential budgetary options that might

be appropriate for varying contingency requirements.

Active-Duty vs. Reserve Manpower

Reliance on both active-duty and reserve manpower for airlift

operations is similarly a product of efforts to reduce peacetime

costs of wartime capacity. Accordingly, MAC relies heavily on

reserve forces. Half of the C-5 and C-141 air crews are now, or

are scheduled to be, filled by reservists, as are 35 percent of

maintenance crews and 50 percent of aerial port personnel.

ll/ Nearly 80 percent of all civilian international cargo transports are in CRAF, as are 55 percent of all wide-body international passenger aircraft. See Civil Aeronautics Board,

War Air Service Program (WASP), Resource Report, Calendar

Year 1978, Tables 3 and 7.

12/ During the Israeli airlift in 1973, for example, CRAF carriers were hesitant to commit airplanes, in part because they

risked a potential loss of landing rights in Arab countries.

It should be noted, however, that CRAF planes operated extensively under contract during the Vietnam War, though without

formal mobilization. Two contending interpretations of CRAF

reliability in times of emergency are found in statements by

General William G. Moore and Admiral Thomas Moorer in The

Posture of the U.S. Military Airlift, Hearings, pp. 43, 142.

11
The use of reserve units substantially reduces annual

operating costs of organic airlift assets. As can be seen

in Table 1, the operating costs of a C-141 squadron and a C-5

squadron would increase by 53 percent and 21 percent, respectively, if current reserve manpower were replaced by active-duty

personnel.

TABLE 1. ANNUAL SQUADRON OPERATING COSTS AT CURRENT MANNING

AND ALL ACTIVE-DUTY MANNING: IN MILLIONS OF 1978

DOLLARS

Current

Manning

All

Active-Duty

Manning

Percent

Increase

C-141 Squadron

Personnel

Direct operating

Indirect support

Total

19.1

26.8

0.3

46.2

23.8

46.3

0.5

70.6

25

73

67

53

C-5 Squadron a/

Personnel

Direct operating

Indirect support

Total

30.0

68.4

0.5

98.9

41.0

77.7

0.9

119.6

37

14

80

21

SOURCE: Information provided to CBO by U.S Air Force (January 10,

1979).

a/ These figures reflect reduced utilization rates because of the

C-5 wing-life preservation program. As such, personnel and

direct operating costs are lower because crews are currently

at a 3.25 ratio rather than the four-crews-per-plane ratio for

the C-141. They will increase when the four-to-one crew ratio

is established for the C-5 as well.

12
According to the Air Force, four air crews per plane are

required to sustain programmed wartime utilization rates. 13/ If

reservists were not called up, only half the airlift capacity

of the organic fleet would be available for emergency requirements. It is doubtful that the President would order deployment

of a substantial combat force without calling up some Air Force

reservists, however. It is important to note that the President

has the statutory authority to call up as many as 50,000 reservists selectively without a general mobilization. Only approximately 13,500 reservists would be required to reach programmed

wartime operating rates for MAC, however.

AIRLIFT OPERATIONS AND THE AIRLIFT SYSTEM

Military airlift has traditionally been characterized by the

dichotomy between strategic (intertheater) and tactical (intratheater) airlift operations and assets. In 1974 the Secretary of

Defense directed the consolidation of all strategic and tactical

airlift operations under the Military Airlift Command. Prior to

that time, MAC was responsible only for strategic mobility, which

was defined as long-distance transportation between theaters of

operation or from the continental United States to a combat

theater. Tactical airlift, previously a function of the Tactical

Air Command and under the control of local commanders, was used to

move troops and materiel within a given combat theater. Although

this distinction between strategic and tactical operations is

becoming somewhat blurred by current and prospective enhancement

programs, it is useful to note the factors that have traditionally

distinguished these two categories.

The Military Airlift Command and the strategic airlift

mission had their origins in the Military Air Transport Service

(MATS). MATS was, for all practical purposes, an air transportation agency for the Department of Defense in the 1940s and 1950s,

equipped with aircraft similar to those operated by the commercial airlines. Renewed emphasis in the 1960s on general

purpose forces contributed to an evolution in MATS, especially

with the introduction of jet technology to air transport. The

procurement of the C-141, and later of the C-5, reflects the

shift from an air transport mission to a strategic, long-range

_13_/ See testimony by Brigadier General Charles C. Irions in The

Posture of the U.S. Military Airlift, Hearings, p. 22.

13
deployment mission. Strategic airlift now involves the deployment

of entire air and ground combat and support units, together

with their equipment and initial supplies, directly from the

continental United States to a combat theater. Through advance

planning, those units can arrive as an integrated fighting force,

requiring only minimal preparation time. 14/

The evolution of tactical airlift has been less dramatic.

Traditionally, the primary function of tactical airlift has

been to provide an air line of communication, bringing small

critical quantities of cargo—often ammunition or important

spare parts—directly to a combat unit. Only 3 to 5 percent of

logistical resupply is airlifted; most supplies are delivered by

ground transportation. Tactical airlift can also conduct airborne operations, such as parachute airdrops of men and equipment. Such missions comprise less than 5 percent of all aerial

delivery, however. 15/ During the Vietnam War, a large portion

of tactical airlift missions consisted of routinely scheduled

passenger flights. With the exception of the Tet offensive,

emergency resupply missions comprised only a small fraction of

total missions.

Aircraft used for strategic and tactical airlift missions

reflect the different requirements of those missions in their

design and size. Strategic transports—the C-5 and C-141—are

designed to carry large cargoes over long distances, as shown

in Table 2. More importantly, because of the differences in

distance between tactical and strategic missions, the C-5 and

C-141 can fly at higher utilization rates than can tactical

transports. 16/

14/ The requirement to transport troops together with their

equipment was reflected in specific procurement designs

of the C-141 and C-5. Both aircraft can carry small numbers

of troops in addition to cargo. The C-141 can carry six

troops in addition to its cargo payload; the C-5, as many

as 71. Through a full deployment operation by air, troops

can thus be delivered at approximately the same time as their

equipment.

JL5_/ Military Airlift, Hearings, p. 6366.

16/ In strategic missions, more time is consumed in actual

flying, thereby increasing system-wide utilization rates.

14
TABLE 2. STRATEGIC AND TACTICAL AIRCRAFT PERFORMANCE DATA

Payload a/

(pounds)

Range b/

(nautical

miles)

Speed cj

(nautical

miles

per hour)

Programmed

Utilization

Rates <d/

(hours)

Number

in Fleet e/

Strategic

C-5

C-141

215,339

67,620

5,900

5,175

428

407

12.5/10

12.5/10

70

234

Tactical

C-130E

C-123

C-7

41,892

14,500

6,000

4,030

2,400

1,175

260

132

107

4.0

2.5

2.5

474

64

48

a_/ Payload is expressed in terms of allowable cabin load (ACL), the

maximum payload by weight. ACL will rarely equal lift potential

achieved, however, since critical distance requirements could lower

payloads.

_b/ The range is the maximum distance a plane can fly with no payload,

known as the "ferrying" range. The ranges given for the C-123 and

C-7 require external fuel tanks.

c/ Speed is expressed in "block-in" speed, which averages cruising speed

with slower speeds during approaches and take-offs. Block-in speeds

and cruising speeds converge as mission distances increase.

&/ Utilization rates are fleet-wide averages of flying time. For strategic transports, the first number reflects the utilization rate

for the first 45 days of an airlift operation. For deployments

requiring more than 45 days, an aircraft will operate at the lower

number for the duration of the deployment. If the utilization rate

for an aircraft is doubled, it will take half as long to perform

the same mission. Utilization rates are determined by the number

of air crews, maintenance crews, and the quantity of spare parts.

Shorter-distance missions always lower overall utilization rates.

e/ Primary Aircraft Authorization (formerly Unit Equipment). These

figures reflect the number of planes assigned to authorized active or

reserve airlift units. Additional planes are held for other purposes.

15

43-168 O-79- 5
A distinction between strategic and tactical airlift operations can also be made in terms of operational conditions.

Strategic transports like the C-5 and C-141 require long runways

with substantial load-bearing capabilities. 17/ The high volume

of traffic in an emergency operation would require airports with

large unloading ramps. These characteristics limit the number of

airports available for strategic operations. Tactical transports

like the C-130 are rugged airplanes, designed to land on rough

surfaces very close to the combat area. Of total usable airfields

in Europe, for example, there are six times as many "tactical" as

"strategic" airfields. IS/

A final factor that affects airlift operations is the

type of cargo to be moved. Military cargo falls into one of four

categories. The first, called "not air transportable" (NAT),

consists of items that, for reasons of size or weight or both,

cannot be carried by any currently available airplane and must be

transported by overland carriers or ships. Only a very few

items—such as locomotives, barges, and rockcrushers—fall into

this category.

Equipment that can be transported by air falls into one of

three categories: bulk, oversize, or outsize. Bulk cargo is

loaded onto freight pallets (104 by 84 inches) which can be

carried by any organic or civilian GRAF airplane. Oversize

17/ The C-5 was designed to land on a relatively short runway of

5,000 feet. While this is still technically possible, such

missions are rarely attempted. Structural problems with the

C-5's wing have imposed constraints that significantly

increase required runway length. In addition, few day-to-day

missions are of sufficient importance to risk the expensive

C-5 in short field operations.

18/ So-called "strategic" fields are those that, because of

combinations of runway length, load-bearing capability,

ramp area, airport lighting, instrument landing equipment

and so on, can be used as airports of debarkation (APODs),

which are major terminals of an airlift operation. "Tactical" fields are those usable fields that do not meet the

above criteria guidelines. Currently, the C-130 can operate

in about half of the tactical fields in Europe and in all

APOD fields. The C-5 and C-141 can operate in less than 25

percent of European airfields.

16
cargo is too large to be loaded on pallets but can be carried by

organic transports, such as the C-130, C-141, C-5, or by wide-body

GRAF planes like the DC-10 or B-747. 19/ The five-ton truck is

an example of "oversize" cargo. Outsize cargo (for example, tanks

and self-propelled guns) cannot be carried on the C-141 and,

because of weight or size, can only be transported by the C-5

Galaxy.

The proportion of bulk, oversize, and outsize cargo varies

by type of combat unit. An armored division has more than 40

times as much outsize equipment (expressed in terms of weight)

as an airborne division and two and a half times the oversize

equipment. All divisions have approximately the same amount of

bulk equipment, although the proportion of bulk equipment to

total divisional cargo is higher in the so-called "lighter"

divisions than in armored or mechanized divisions. As discussed

in Chapter III, the mix of cargo to be transported has a direct

impact on strategic airlift performance.

19/ The C-130 and the C-141 have the same cross-section cargo

compartment. The C-1411s cargo compartment is longer than

that of the C-130, however. Some equipment that can be

carried intact by the C-141 must be disassembled to be

transported on the C-130.

17

CHAPTER III. OPERATIONAL PERFORMANCE OF THE AIRLIFT SYSTEM

This chapter examines the current capabilities of the

airlift system and the effect that different improvement programs would have on its performance. The chapter begins with

a discussion of the overall system in terms of airlift capabilities, outlining the relationship of the various structural

components. The chapter concludes with an examination of the

contribution of various enhancement programs currently before

the Congress.

CAPABILITIES OF THE CURRENT AIRLIFT SYSTEM

Organic transports and civilian reserve aircraft make

roughly equal contributions to total airlift capacity, as shown

in Table 3. The real capability of the airlift system, as well

as limitations on its ability to meet airlift requirements

in the future, is a function of several complex factors beyond

the number of planes available and their lift potential. In any

given contingency, the distance that must be flown is a major

determinant of the time—frequently known as "closure time"—

required to complete a mission. Equally important is the nature

of the contingency and the mission assigned to American combat

units. Some missions and combat environments require a "heavy"

force, consisting of armored and mechanized units. At other

times, "lighter" combat units—such as the 82d Airborne Division or the 6th Air Cavalry Combat Brigade—might satisfy combat

mission requirements. A mechanized or armored division might

be preferable if similar units would be confronted in combat,

but that obviously would require more airlift capacity over

a longer period of time. Table 4 illustrates the distribution

of bulk, oversize, and outsize cargo among the five basic types

of Army divisions. As the table indicates, a mechanized division weighs more than three times as much as the 82d Airborne

Division. Since bulk cargo for the two divisions is relatively

equal, the difference is attributable primarily to the amount

of outsize and oversize unit equipment fielded by the two types

of divisions.

19
TABLE 3. PROGRAMMED AIRLIFT CAPABILITIES BY TYPE OF AIRCRAFT

Million

Ton-Miles

Per Day

Organic Airplanes

C-5 11.5

C-141 11.1

GRAF

Wide-body cargo 4.8

Narrow-body cargo 5.6

Passenger —

Total 33.0

Million

Passenger-Miles Percent

Per Day of Total

21

20

Q

10

146.7 a/ 40 a/

146.7 100

SOURCE: See Appendix A.

a] Passenger-miles are converted to ton-miles for purposes of

comparison, by assuming that the average weight of each

passenger and his gear is 300 pounds.

TABLE 4. ESTIMATED AIRLIFT REQUIREMENTS BY TYPE OF DIVISION:

TONS FOR 1976

IN SHORT

Outsize

Division

Type

Armored

Mechanized

Airmobile

Airborne

'Infantry

Short

Tons

27,658

21,213

1,702

593

7,760

Percent

50

44

11

4

26

Oversize

Short

Tons

21,704

21,577

8,345

8,814

16,395

Percent

39

44

55

60

55

Bulk

Short

Tons

5,979

5,778

5,182

5,226

5,596

Percent

11

12

34

36

19

Total

55,341

48,568

15,229

14,633

29,751

SOURCE: Information provided to CBO by U.S. Air Force,

20
The density (that is, the weight per unit volume) of cargo

to be transported also varies among division types. Density

determines the payload an aircraft can carry, subject to the

overall constraint of maximum take-off weight. The higher

the density, the greater the payload. Average payloads for

the five types of Army divisions are shown in Table 5. While

a mechanized division might weigh three times as much as an

airborne division, it might take only twice as long to deploy,

since planes carrying equipment of a mechanized division can

average payloads 60 percent greater than those carrying an airborne division.

Figure 1 illustrates the relationship among the many variables that determine airlift capacity. The curves in the figure

relate distance to closure time by type of unit. It should be

noted that these curves are highly approximated and indicate

transit time only. They are useful in demonstrating relationships, however, since important variables and assumptions are held

constant throughout. JY

Three types of divisions are shown: the 82d Airborne

Division, a hypothetical infantry division, and a hypothetical mechanized division. 2J Lines parallel to the horizontal

axis indicate distances of various possible destinations from

U.S. ports of embarkation. As distance increases, so does the

length of time needed to deliver the respective types of combat

forces.

Because of variations in airplane characteristics and in

cargo weight, density, and composition, delivery curves for each

type of division have differing slopes. _3_/ Since airlift forces

are procured and maintained primarily to ensure rapid delivery

I/ See Appendix A for a discussion of the methodology used in

this paper.

21 Mechanized and infantry divisions vary slightly in weight;

therefore, "average" divisions are used. Since the Army

has only one airborne division, specific tonnages are given.

•

3/ The delivery rates relate the change in closure time to

changes in distance, assuming that cargo and lift variables are held constant.

21
TABLE 5. AVERAGE PAYLOADS FOR ORGANIC AND CIVILIAN RESERVE

PLANES: BY TYPE OF DIVISION, AVERAGED OVER A CRITICAL

LEG OF 3,100 NAUTICAL MILES a/

Average Payload in Tons , by Type

Division

Type

Armored

Mechanized

Infantry

Airborne

Airmobile

C-5

68.5

68.5

68.5

54.6

30.1

C-141

20.8

20.8

17.8

13.9

12.9

GRAF

707 b/

30.0

30.0

30.0

30.0

30.0

of Plane

GRAF

747 cj

72.9

72.9

72.9

72.9

72.9

SOURCE: Air Force Regulation 76-2.

aj Distance from Elmendorf Air Force Base, Alaska, to Yokota,

Japan.

_b/ Narrow-body commercial transports are converted to a common

unit, characterized as B-707 equivalents. Differing speeds,

payloads, and volume factors for each type of plane are

indexed against the B-707. These aircraft can transport

bulk cargo only.

cj This refers to B-747 equivalent units. The average payload

for the 747 is computed as 75 percent of maximum allowable

cabin load over distances comparable to those used to compute

payloads in the first two columns. While wide-body aircraft

can transport oversize cargo, not all of the usable volume of

the cargo compartment can carry oversize equipment. For

purposes of these calculations, it is assumed that 75 percent

of the payload is oversize and the remaining 25 percent is

bulk cargo.

22
Figure 1.

Delivery Time as a Function of Distance, by Type of Division'

Distance from Continental U.S. (in nautical miles)

10,000

9,000 -

Hypothetical

Mechanized

Division

Charleston AFB

to Persian Gulf

Charleston AFB

to Panama Canal

2,000 -

1,000 -

0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30

Time to Deliver Farces (in days)

a

 Divison includes initial support increment.

23

43-168 O - 79 - 6
of combat units, it is of primary interest to examine the slopes

of these lines, the factors that affect those slopes, and how they

might be altered by the varying enhancement programs currently

before the Congress or expected to be considered in the near

future.

Table 6 provides delivery rates (more technically, slope

coefficients) for the three types of divisions, relating the

contribution of the various elements of the airlift system

discussed in the preceding chapter to closure time. Higher

numbers indicate faster delivery rates. Several observations

can be offered. First, a heavy division takes roughly half again

as much time to deploy as the lightest division, the 82d Airborne.

Since the proportion of outsize cargo in a mechanized division

far exceeds that of the 82d Airborne, the C-5 must carry more

outsize cargo and cannot carry as much bulk and oversize cargo

as it can when transporting a lighter division. Indeed, an

airlift enhancement program that does not increase outsize capacity will only minimally improve overall closure times for heavy

divisions.

Second, full GRAF augmentation cannot compensate for the

absence of reservists flying organic transports. Because GRAF

aircraft lack outsize cargo capacity, loss of organic lift

can be compensated for by GRAF augmentation only to a limited

extent. Indeed, if a mission called for delivery of a mechanized division, full GRAF augmentation could not compensate

for the outsize capability lost because of lower utilization

of the C-5.

Third, if neither GRAF augmentation nor reserve components were available during an airlift operation, closure times

for airborne, infantry, and mechanized divisions would be increased by 150 percent, 150 percent, and 120 percent, respectively. If an airlift operation was conducted over a very long

distance (6,300 nautical miles to the Persian Gulf, for example), it might take as long as three weeks to deliver a mechanized division and as long as seven weeks if no GRAF augmentation and lower organic asset utilization compounded airlift

problems. 4/

Ships could potentially reach a Persian Gulf port in five

weeks.

24
TABLE 6. AIRLIFT PERFORMANCE AT FULL AND REDUCED SYSTEM OPERATIONS

Delivery Rate by Type of Division a/

82d Hypothetical Hypothetical

Airborne Infantry Mechanized

Full Organic/

Full CRAF b/

Full Organic/

No CRAF £/

Partial Organic/

Full CRAF d/

.55

.39

.35

.45

.32

.27

.33

.27

.17

Partial Organic/

No CRAF e/ .22 .18 .15

SOURCE: See Appendix A.

aj Expressed in thousand miles of distance per day for each

type of division. For example, ".55" for the 82d Airborne

Division indicates that, for each day of delivery time permitted, the division can be transported approximately 550

miles.

b/ All organic assets at programmed utilization rates; full

CRAF augmentation; strategic augmentation by tactical

airlift.

cj All organic assets at programmed utilization rates; no

CRAF augmentation; strategic augmentation by tactical

airlift.

d/ Organic planes flown at reduced rates because of absence

of reservists; full CRAF augmentation; strategic augmentation

by tactical airlift.

.§./ Organic planes flown at reduced rates because of absence of

reservists; no CRAF augmentation; strategic augmentation by

tactical airlift.

25
THE EFFECT OF ENHANCEMENT PROGRAMS ON AIRLIFT PERFORMANCE

This section examines the effec t of various enhancement

programs on airlift performance. Since the different elements of

the airlift system contribute in varying measure to airlift

performance, enhancement programs will also have differen t

effects, depending on which element of the system is altered.

Aircraft Conservation: C-5 Wing Replacement

The C-5 wing modification program is not in itself an

enhancement initiative, since it will not increase airlift

capacity. It will, however, conserve a crucial element of the

current system. The C-5 was initially intended to have a service

life of 30,000 hours. _5_/ Numerous structural problems were

uncovered during production and testing, many of which were

corrected by a formal system of engineering changes. Despite

these modifications, surface wing-panel cracking (occurring

at fastener holes where panels were spliced together) persisted,

leading to a major engineering review program. This review

concluded that structural components of the wing will have

to be replaced if the C-5 is to achieve a service life of 30,000

flying hours.

The C-5 re-winging program, proposed by the Air Force,

would involve the manufacture and installation of a new wing

at an estimated cost of $1.1 billion in 1980 dollars. A Defense

System Acquisition Review Council (DSARC) is scheduled to meet in

September 1979 to determine whether or not to proceed with

production and installation of a new wing. If that review is

favorable, the modification program will begin in 1981. The

fiscal year 1980 budget proposal provides $78.6 million to manufacture components for seven wings. The Congress must decide this

year whether to proceed with the program as proposed by the

_5_/ Actually, the 30,000-hour service life objective was not

formalized in the C-5 contract. Nonetheless, it was understood to be a design objective. This analysis relies heavily

on a Rand Corporation study of strategic airlift alternatives for the future. See W.E. Hoehn and others, Strategic

Mobility Alternatives for the 1980s: Volume 3, Technical

Appendixes (Santa Monica: The Rand Corporation, March 1977),

especially Appendixes B through H (unclassified).

26
Department of Defense. Air Force spokesmen have labeled the C-5

wing modification program as their first priority among all

airlift enhancement programs. _6/ Without the alteration, they

contend, the C-5 will have to be retired from service by the

mid-1980s.

While the C-5 contributes only 21 percent of total airlift

capacity, it is the only transport—civilian or organic—currently

in the fleet that can carry outsize cargo. The importance of the

C-5 to strategic airlift capability is demonstrated in Table 7.

The impact of losing C-5 capability differs by type of division.

TABLE 7. CLOSURE TIME AS A FUNCTION OF C-5 AVAILABILITY

Delivery Rate by Type of Division a/

82d

Airborne

Hypothetical

Infantry

Hypothetical

Mechanized

Full Organic /Full GRAF

25 Percent Reduction

in C-5 Fleet Capacity

50 Percent Reduction

in C-5 Fleet Capacity

75 Percent Reduction

in C-5 Fleet Capacity

.55

.51

.42

.21

.45

.40

.27

.14

.33

.25

.17

.08

No C-5 Contribution

SOURCE: See Appendix A.

a/ Expressed in thousand miles of distance per day for each type

of division. For example, ".55" for the 82d Airborne Division

indicates that, for each day of delivery time permitted, the

division can be transported approximately 550 miles.

6/ See The Posture of Military Airlift, Hearings before the

Subcommittee on Research and Development, House Committee on

Armed Services, 94:1 (November 1975), p. 225.

27
Light divisions would not be affected as dramatically as heavier

divisions by a reduction in outsize cargo capacity. Nonetheless,

total division closure time is directly related to the availability of C-5s. As can be seen, closure times increase as the

number of C-5s decreases. If no C-5s were available, however,

no outsize cargo could be transported. The 82d Airborne Division

could probably function as a combat unit under such circumstances,

but a mechanized or armored division could not.

Since it would cost $1.1 billion to modify the C-5, the

decision merits close examination. There certainly is no question

that the C-5 is indispensable to current strategic airlift capabilities. It is equally clear that the current wing will not

attain a 30,000-hour service life. The Congress may, however,

wish to question whether a 30,000-hour service life is still a

necessary design goal for the C-5.

The C-5 service life of 30,000 hours was based on initial

plans to fly each plane 1,800 hours a year. Currently, utilization rates are held to 1.8 hours a day, which, over a year, totals

657 hours. Even with a new wing, MAC intends to operate the C-5

fewer than 800 hours a year. TJ The C-5 was originally intended

to have an active life span of 17 years. If the new wing does

permit a 30,000-hour service life, and the remainder of the airframe can perform to that goal as well (which is questioned by

some), the plane would potentially remain in the active fleet 38

years after modification. Within that time period, an entirely

new generation of military/civilian cargo transports is anticipated. 8/ Since 14 years will have elapsed between the end of

2J Information provided to CBO by the U.S. Air Force (March 26,

1979).

8/ The Air Force has been examining the possibilities of a

follow-on cargo transport. NASA and USAF Systems Command have

contracted with a Washington area research corporation to

examine technical and cost questions associated with any proposed C-XX. (XX stands for the numerical designation of the

new plane.) Central to the idea of a new transport is the

prospect for designing an aircraft that would be commercially

feasible and yet have a militarily useful design configuration. In the past, all commercial transports were modified

passenger planes. See "USAF Plans Cargo Aircraft for the

1990s," Flight International (August 12, 1978), p. 461.

28
production of the C-5 and the completion of the wing replacement

program, it could be questioned whether an additional 30,000

hours, or 38 years, is necessary. If the Congress determines that

a service life of fewer than 30,000 hours is acceptable, several

options—costing considerably less than the wing replacement

proposal—might be considered.

One such alternative would limit modification to a relatively simple fastener change. This modification, in conjunction

with a less conservative estimate of the safe service life, 9/

could produce substantial fleet life extension at far less

cost than the DoD program. As Table 8 indicates, a fastener

change on low-damage aircraft, combined with a 10,000-hour

service limit, would extend the useful life of the C-5 flee t

until the end of the century. The Rand Corporation has estimated

that this adjustment could be made at about one-third the cost of

the re-winging program proposed by the Air Force. 10/ Modifications more extensive than a fastener change, though less extensive

and less costly than full re-winging, could also be made. A

Congressional decision on the desired service life of the C-5

should be made in the context of related enhancement programs.

Alternative airlift improvement objectives, having differin g

policy implications for the C-5, are outlined in Chapter IV.

Aircraft Alteration; The C-141 Stretch Program and GRAF Modification

The second type of improvement program involves modification

of existing aircraft to increase their productivity. A distinction should be made between programs involving organic transports

and the GRAF program, which affects commercial aircraft.

9/ The Air Force projects an 8,000-hour service life for the

C-5 without re-winging. This is not the point at: which wing

failure can be expected, however. Rather, it is a calculation based upon engineering estimates of the rate of crack

growth and the optimal time for replacement of faulty

components. Thus, a less conservative estimate of safe

service life could result in a 2,000-hour service life

extension (see last column of Table 8).

10/ CBO has updated the earlier Rand estimate to account for

inflation and several additional costs (see p. 60).

29
TABLE 8. AN OVERVIEW OF OPTIONS FOR EXTENDING THE SAFE SERVICE LIFE OF THE

C-5 WING a/: GIVEN UTILIZATION RATES (HOURS PER YEAR) OF 700 HOURS

AND 500 HOURS

Description

of Structural

Modification

Options

Cost

(millions of

8,000-Hour

Safe Service

Limit

700 500

2,000-Hour

Service Limit

Extension

700 500

1975 dollars) hours b/ hours b/ hours b/ hours b/

No Change

Fastener

Change on

62 Low—Damage

Aircraft

Alter Current

Wing on 15

High-Damage

Aircraft

Complete Wing

Modification on

15 High-Damage

Aircraft

Alter Current

Wing on All

77 Aircraft

Complete Wing

Modification on

All 77 Aircraft

1983 1986 c/ 1987 1991

267

239

480

610

910

1989 1994 1992 1999

1986 1990 1990 1996

1989 1995 1993 2000

1997 2006 2004 2016

2014 2030 2018 2035

SOURCE: Adapted from W.E. Hoehn and others, Strategic Mobility Alternatives

for the 1980s: Volume 3, Technical Appendixes (Santa Monica: The Rand

Corporation, March 1977), p. G-12 (unclassified).

a/ Calculations assume a 25 percent life extension because of the Active Lift

Distribution Control System (ALDCS), which is an engineering change that

reduces wing stress.

_b/ Based on 1976 mission use. Subtract 1.5 to 2.0 years for the equivalent

life-reducing effect of each NATO deployment of eight division equivalents.

30
The C-141 Stretch Program. According to Air Force studies,

C-141 payloads are almost always limited by available floor

space or cabin volume. Since space limits are generally reached

before weight limits, ll/ excess lift capacity goes to waste.

To use that capacity fully, the Air Force has proposed to manufacture and insert an additional 23 feet of fuselage on the

fleet of C-l41s. This would increase their potential payload

by as much as 30 percent, with only an insignificant increase in

annual operating and personnel costs. 12/ The C-141 modification

program, which includes adding aerial refueling capability, is

estimated to cost $505 million. Proponents contend that a comparable increase in organic capacity could be achieved only by

adding 90 new C-l4ls to the fleet at an initial procurement cost

of more than $2.4 billion as well as additional operating costs

over their lifetime. 13/

The C-141 stretch program clearly provides increased lift

capacity at less cost than procuring new organic planes. The

program has been challenged on cost grounds on the basis of

other criteria, however. Other mobility alternatives have

been suggested as less costly means of improving airlift performance. As noted in the next chapter, however, more effective

alternatives at equal or less cost might not be available for

ll/ The primary reason for this is that the density of bulk and

oversize cargo is frequently less than the optimal density of

cargo in which lift potential equals volume limits (known as

the cross-over cargo density) in the C-141. By increasing

volume capacity without changing lift potential, the crossover cargo density is lowered, bringing it more in line with

actual cargo densities. Ironically, stretching the C-141

would decrease its maximum airlift potential because of the

added weight of the two fuselage inserts. Productive airlift

would increase, however, because remaining lift could be used

more efficiently.

12/ The actual increase in productivity varies by type of

cargo. A light unit, like the 101st Airmobile Division,

would still fill out the cargo compartment before reaching

payload limits. Nonetheless, the proportionate increase in

payload with the modification is greater for lighter divisions than for heavier divisions.

13/ See The Posture of Military Airlift, Hearings, p. 361.

31

43-168 O - 79 - 7
non-NATO contingencies, a factor which certainly should weigh in

any evaluation of the program by the Congress.

GRAF Modification. A second aircraft alteration plan

involves civilian reserve airplanes under the CRAF program.

The Air Force proposes to modify, at government expense, commercial wide-body passenger planes by equipping them with cargo

features. B-747s and DC-lOs (and possibly L-lOlls) would be

equipped with cargo doors and given stronger floors. In a CRAF

mobilization, seats, overhead luggage racks, and kitchen and

lavatory units would be removed from the planes. Cargo equipment

such as floor rollers and side rails, stored by the airlines at

depot facilities, would then be installed.

The CRAF modification program was first proposed by the Air

Force several years ago; the Congress, however, has not yet authorized full implementation of the program. The House of Representatives passed authorizing legislation in the 95th Congress for

the CRAF modification program, 14/ but the measure was not taken

up by the Senate. 15/ Instead, $7.5 million was appropriated

14/ This legislation, H.R. 2637, provided statutory authority for

the Secretary of the Air Force to establish a program to

encourage civil air carriers to acquire additional cargo

capacity in their future fleets and to modify existing airplanes by installing militarily acceptable cargo features.

The bill would have accomplished this by (a) funding the

installation of cargo features in new passenger planes and

compensating the airlines for lost revenue potential as a

consequence, (b) funding the installation of similar features in existing passenger planes, and (c) contributing to

purchase costs of new cargo planes or planes with cargoconvertible features.

15/ The CRAF program has been unevenly received in the Congress.

The House Committee on Armed Services strongly favors the

concept. See Amending Title 10, United States Code, H. Rept.

95-776, 95:1 (1977). The Subcommittee on Defense of the

House Committee on Appropriations, however, recommended

termination of the entire program. See Department of Defense

Appropriations Bill. 1977, H. Rept. 94-1231, 94:2 (1976), pp.

152-53. Both the Senate Committee on Armed Services and the

Senate Committee on Appropriations favor CRAF modification,

though only for new passenger planes.

32
in fiscal year 1979 to fund a demonstration program under which

one new commercial jet would be modified as a test of potential

program costs and performance. The DoD budget for fiscal year

1980 proposes to modify nine new commercial aircraft at a cost of

$73.6 million. Eventually, as many as 88 planes could be altered

under the program. 16/

The GRAF modification program builds on the intrinsic cost

advantages of civilian reserve augmentation. Like the GRAF

system itself, the program would impose no additional peacetime

operation and maintenance costs once the cargo features have been

installed and compensation and incentive payments have been made.

The costs of a GRAF modification program, and the resulting

increase in airlift capacity, would depend on the type of aircraft modified. DoD expects to modify about 65 planes in the

next five years, adding 10.0 million ton-miles per day capacity,

at a cost of $550 million.

C-141 Stretch vs. GRAF Modification. The C-141 stretch and

GRAF modification programs are frequently compared, since both are

designed to increase oversize cargo capacity. Table 9 compares

the effect of these programs on airlift performance.

Comparisons of the effect of the C-141 stretch and GRAF

modification programs are generally made on the basis of system

performance, given full organic and GRAF augmentation. Comparing

the last two lines of Table 9 with the third line shows that,

except for heavy divisions, the GRAF modification program provides

greater airlift performance improvement than the C-141 stretch

program. The stretch program increases performance by less than 5

percent, compared to the 25 percent improvement for airborne and

infantry divisions achieved by the GRAF modification program. IT/

16/ DoD hopes to modify a sufficient number of planes to equal

the capacity of 65 B-747s. It could take as many as 88 of

the smaller DC-lOs to equal that capacity.

17/ The delivery rates for heavy divisions are artificial in that

performance for Table 9 was computed for the transportation

of only one division and its support units. If resupply is

taken into account, both the C-141 stretch and GRAF modification programs will increase performance. Measured by gross

tonnage delivered, the GRAF program provides greater cargo

capability at less cost than the C-141 stretch program.

33
TABLE 9. AIRLIFT ENHANCEMENT: EFFECTS OF C-141 STRETCH VS. CRAF

MODIFICATION PROGRAMS

Delivery Rate by Division Type a/

82d Hypothetical Hypothetical

Airborne Infantry Mechanized

Full Organic/

No CRAF b/ .39 .32 .27

Full Organic/

No CRAF

plus C-141 Stretch .42 .34 .28

Full Organic/

Full CRAF .55 .45 .33

Full Organic/

Full CRAF

plus C-141 Stretch .58 .47 .33 c/

Full Organic/

Full CRAF

plus CRAF

Modification

Program .70 .55 .33 c/

SOURCE: See Appendix A.

a/ Expressed in thousand miles of distance per day of time for

each type of division. For example, ".39" for the 82d Airborne Division indicates that for each day of delivery time

permitted, the 82d can be transported approximately 390

miles.

_b/ Organic transports operated at programmed utilization rates.

c_/ The closure rate of a heavy division does not improve with

either the C-141 stretch or CRAF modification program since

outsize cargo capacity—provided by the C-5 alone—remains

unchanged. For lighter divisions, the C-5 will carry oversize

cargo, even with these two enhancement programs.

34
Such comparisons do not take into account the full range

of benefits offered by the C-141 stretch program, however. The

GRAF modification program would improve airlift performance

only when the CRAF fleet was activated, and then only at a Stage

III mobilization. The stretch program, on the other hand,

would increase airlift performance even when no CRAF augmentation was available. The first two lines of Table 9 indicate

that the stretch program could increase airlift performance by

as much as 8 percent even without CRAF augmentation.

This conclusion has important implications. The CRAF

fleet has never been activated in its entire history. While

it undoubtedly would be activated in the event of a major conflict, it is questionable whether CRAF augmentation would be

available for lesser contingencies. Mobilization of the fleet

could have a disruptive effect on the domestic economy and,

short of a full war, it is doubtful that full CRAF augmentation, with or without modified planes, would be available.

Aircraft modified under such a program must be committed to

CRAF, but only at a Stage III mobilization. This reflects

a fundamental assumption of the CRAF modification program:

the program is largely designed to meet airlift requirements

associated with a NATO/Warsaw Pact war. The cost advantages

of the CRAF modification program compared to the C-141 stretch

program might be less distinct in situations in which a full

CRAF mobilization is unlikely. Thus, it can be argued that the

C-141 stretch program is the preferable alternative if airlift

improvement is designed primarily to satisfy future non-NATO

contingencies.

Aircraft Procurement

Aircraft procurement introduces more complicated (and

more expensive) considerations. A large fleet of organic planes

already exists. Since these aircraft would be augmented by

CRAF planes in the most demanding contingencies, decisions

regarding procurement of new organic transports must consider

the economic advantage of civilian reserve augmentation. There

are clear instances, however, when civilian counterparts would

not be available to augment organic transports. Recently, the

Air Force has sought procurement of two organic systems—the

Advanced Tanker/Cargo Aircraft (ATCA) and the Advanced Medium

Short-Takeoff-and-Landing Transport (AMST)—neither of which

has a civilian counterpart.

35
The Advanced Tanker/Cargo Aircraft. The ATCA is essentially

a commercial wide-body jet—the DC-10—modified to incorporate

aerial refueling equipment. The lower cargo compartments of the

aircraft contain fuel tanks for aerial refueling operations. The

upper compartments contain seating for 80 crew members and passengers; cargo storage space is provided to the rear of the small

passenger compartment.

The procurement concepts underlying acquisition of the

ATCA represent a compromise between organic and civilian reserve

airlift assets. Aerial refueling does not require unique military

design features, except for a refueling boom that can be installed

on many existing airframes. 18/ The ATCA program, therefore,

presents an opportunity to adapt an existing commercial aircraft

for military application, thus avoiding the research and development costs normally associated with procurement of new weapons

systems. 19/ Further, ATCA procurement assumes that the Air Force

will provide only minor routine maintenance, with any heavy

maintenance provided by commercial contractors at commercial

facilities, thus avoiding the indirect support costs associated

with active-duty and reserve maintenance manpower and facilities.

The ATCA (formally designated the KC-10) was initially

intended to succeed the aging KC-135, which first entered the

fleet in 1956. 20/ (The KC-135 was a developmental prototype of

18/ On a per-plane basis, ATCA's unique military features will

account for less than 16 percent of its total cost. See

Military Posture and H.R. 10929 (Department of Defense

Authorization for Appropriations for Fiscal Year 1979),

Hearings before the House Committee on Armed Services, 95:2

(February, March, and April 1978), Part 2, p. 468.

19/ The Air Force also found that substantial savings could

be realized if procurement followed schedules suggested by

the contractor. The contractor is prepared to discount

its prices if procurement fits its production schedules.

20/ In 1975 and 1976, DoD decided to cancel plans for development

of a new tanker, adopting instead the current proposal to

modify an existing airplane. See Military Posture and H.R.

11500 (Department of Defense Authorization for Appropriations for Fiscal Year 1977), Hearings before the House Committee on Armed Services, 94:2 (February 1976), Part 2,

p. 237.

36
the Boeing 707 series.) Compared with the KC-135, the ATCA

reflects the performanc e improvements generally associated

with wide-body jets in comparison with the first family of

commercial jet aircraft. For example, at 2,500 nautical miles,

the KC-10 can unload nearly three times as much fuel as the

KC-135. 21/ Thus, on a flight to Europe, a KC-135 can refuel

only two fighte r aircraft, whereas a KC-10 can refue l four

aircraft and transport 30,000 pounds of support equipmen t as

well. 22]

In 1978 the Department of Defense stated that the KC-10 would

be procured not to replace the KC-135, but rather to supplement

anticipated shortfalls in tanker capacity. DoD expects demands

for aerial refueling to increase because of anticipated increased

use by strategic airlift and by tactical fighters within theaters

of operation during wartime. 23/ DoD currently justifies procurement of the KC-10 in terms of its potential use as a tanker in

limited contingencies. 24/

Aerial refueling improves airlift performance in two ways.

First, it reduces total flight time by eliminating ground refueling stops. Second, by removing "critical leg" constraints, it

permits greater payloads. 25/

21] Ibid., p. 239.

22J Ibid.

23/ Military Posture and H.R. 10929, Hearings, Part 2, pp.

469-70.

24/ U.S. Department of Defense, Annual Report, Fiscal Year 1980,

p. 20.

25/ An airplane can lift a given amount of weight, consisting of the plane itself, its cargo, and its fuel. At

some distance unique to each type of plane, a direct tradeoff exists between the quantity of fuel and the quantity

of cargo; to fly beyond that distance without refueling

requires carrying more fuel, which in turn lowers the

amount of lift capacity that can be allocated to cargo.

The longest unrefueled distance a plane must travel on

any given trip—termed its "critical leg"—determines

the payload for the entire trip. If the "critical leg"

37
Aerial refueling can have substantial benefits if an airlift

operation must be conducted over a long distance without intermediate refueling facilities. During the 1973 airlift to Israel,

for example, overflight and refueling rights were denied by most

European and Mediterranean littoral states. Fortunately, intermediate refueling was available at Lajes Field in the Azores. Had

that not been the case, transports would have had to fly 5,500

nautical miles without refueling. At that distance, the C-5 could

have carried only 33 tons of cargo and the C-141 could not have

made the trip at all. Aerial refueling would have permitted

larger payloads for both planes. 26/ The experience of the

Israeli airlift has been cited frequently as a justification for

providing aerial refueling capability for the C-141 and for

procuring the KC-10.

It is important to introduce a qualification at this point.

If overflight rights are assured and intermediate ground refueling

is available (as it was in 1973), the value of aerial refueling

is substantially diminished. Aerial refueling provides only

an inconsequential improvement in airlift performance in such

favorable circumstances. 27/ The 1973 airlift did demonstrate

the potentially adverse effect of political restrictions, such as

denial of overflight and ground refueling rights. Nonetheless,

is beyond the optimal fuel/cargo point and ground refueling stops are unavailable, payloads must be reduced so

that extra fuel can be carried. For example, if a C-5

must travel 3,800 nautical miles without refueling, it

has an allowable cabin load (ACL) of 86 tons. If it must fly

5,240 nautical miles without refueling, its allowable cabin

load drops to 42.5 tons. Aerial refueling permits a plane to

fly with a maximum payload, unconstrained by the "critical

leg."

26/ The Air Force has calculated that aerial refueling during the

Israeli airlift could have saved 44 C-5 missions and 57 C-141

missions, out of a total of 145 C-5 missions and 421 C-141

missions. See The Posture of Military Airlift, Hearings,

p. 32.

27/ A DoD computer simulation of an airlift operation, run

specifically for this study, indicated that if route and

refueling restrictions are eliminated, aerial refueling

improves delivery performance by less than 1 percent.

38
the nature of Arab-Israeli hostilities and third-party fear of

Arab economic retaliation combined to make this an unusual case.

While similar or parallel conditions could develop in the future,

it would be difficult to assign a specific level of plausibility

to such an event. So long as aerial refueling capacity can be

added to airplanes at a modest cost, it is probably a useful hedge

in anticipation of such situations. 28/

The procurement cost of a fleet of 20 KC-lOs would be approximately $1 billion. Since this is a substantial expenditure,

the Congress will want to be certain that the extra tankers

are needed. The Air Force has concluded that as many as 1,000

KC-135 equivalent tankers (the United States currently has 615

KC-135s) would be needed to meet projected wartime tanker requirements by the mid-1980s. 29/

The Air Force study assumes that those requirements—aerial

refueling of strategic bombers, deploying and employing fighters,

and refueling transports—are additive, however. The Congress may

wish to question the assumption that all tanker requirements would

coincide. 30/ CBO has previously concluded that a total of 250

KC-135s would satisfy aerial refueling requirements for a full

28/ Installation of refueling receptacles in the C-141, in conjunction with the stretch program, increased the modification

costs by less than 10 percent. W.E. Hoehn and others, Strategic Mobility Alternatives for the 1980s: Volume 2, Analysis

and Conclusions, p. 35 (information cited is unclassified).

29/ See Military Posture and H.R. 10929, Hearings, Part 2,

p. 469-70.

30/ Current plans call for procurement of 20 KC-lOs, even though

as many as 91 planes were proposed in previous years, with no

apparent increase or decrease in assumed refueling requirements. Indeed, the most recent study, suggesting a mid1980s requirement for more than 1,000 KC-135s, coincided with

the decision to reduce the proposed procurement from 91

planes to 20. Those 20 planes, assuming their maximum

productivity advantage over the KC-135, will satisfy little

more than 25 percent of the assumed tanker deficiency.

It is certainly not clear that a consistent assessment of

requirements has determined the extent of tanker replacement

or addition.

39
airlift operation to the Persian Gulf. 31/ Although this would

present one of the most demanding tanker requirements for airlift

operations, it still would only take roughly 40 percent of the

KC-135 fleet. And if intermediate refueling stops were available,

aerial refueling would not be necessary. Since the KC-10 program

involves an existing airplane with production expected well into

the 1980s, there is no urgency to proceed with further procurement

now. Indeed, in light of the apparent uncertainty about the role

of the KC-10 in meeting assumed tanker requirements, the Congress

may wish to examine the ATCA program at greater length before

authorizing additional procurement.

The Advanced Short-Takeoff-and-Landing Transport. The

second aircraft procurement program involves modernization of the

tactical (or intratheater) airlift fleet. Until last year, it was

assumed that this modernization would be through acquisition

of the Advanced Medium Short-Takeoff-and-Landing Transport (AMST).

The AMST emerged as a candidate for the tactical airlift fleet of

the future as a result of two major factors. First, the Vietnam

War imposed a significant toll on the main tactical transport,

the C-130, in terms of usable lifetime. In 1970, the Congress

directed MAC to investigate a follow-on aircraft to the C-130 that

would incorporate jet and short-takeoff-and-landing technologies.

Second, accompanying the development of Air Force design specifications, the Army strongly argued for a need to acquire tactical

transports that could carry outsize equipment. 32/ The design

specifications, therefore, called for a tactical transport capable

of carrying outsize cargo and operating in a short, rough field

environment.

Central to the debate over procurement of the AMST is the

nature of tactical airlift modernization and the mission of

tactical airlift in the future. The Air Force states that

tactical airlift modernization should be judged by the capacity of

31/ Congressional Budget Office, U.S. Projection Forces: Requirements, Scenarios, and Options, Budget Issue Paper for

Fiscal Year 1979 (April 1978), especially Appendix D.

32/ As originally envisioned by the Air Force, the proposed

new medium tactical transport was not designed to carry

outsize cargo. That requirement evolved during the program development stages. See Military Airlift, Hearings,

p. 6393.

40
the air fleet of the future to move combat units by air. This

is consistent with previous Air Force design goals, though

it differs substantially from previous applications of tactical airlift. Tactical transports have most frequently been

used to move emergency cargo, and only rarely to deliver combatequipped fighting units. This limited role could have developed, however, because there were no tactical transports in

the fleet capable of carrying all the equipment of a combat

unit. Air assault operations were rare even when aircraft

were able to transport most equipment. Tactical airlift modernization can thus be considered on the basis of two opposing assumptions about battlefield airlift requirements in the

future. If tactical airlift is to be restricted to traditional

air logistics operations and to the resupply of bulk and oversize cargo, modernization could most economically be achieved

by replacing aging C-l30s with newer versions or by extending

the service life of older C-130s. 33/ If, on the other hand,

tactical airlift is to be expected to transport combat units,

acquisition of an outsize cargo carrier would be essential. 34/

3_3_/ The Air Force estimates that, if tactical airlift modernization is limited to transport of bulk and oversize

cargo, a fleet of C-130s (model H) over a 15-year life

cycle would cost $12.8 billion to procure and operate. A

fleet of AMSTs, providing similar capacity (measured in

bulk ton-miles), would cost $17.4 billion over the same

period.

34 Proponents of the AMST base most justifications for the

plane on the stated requirement for a so-called "unit

move," which would involve the air delivery of a combat

unit and its equipment within a tactical theater. Proponents of the unit-move requirement contend that air delivery saves critical time, as reflected in casualty figures

and battleline changes calculated through sophisticated

war-gaming models. Opponents of the requirement contend

that the redundancy of the current transportation network

in Europe assures ground transportation availability.

Further, they argue that, in the magnitude of an expected

conflict, air delivery of a battalion or a brigade is inconsequential, given the cost associated with that capability. This argument raises a very complex problem

with respect to war planning. The AMST might conceivably

cost $8.3 billion. The equipment for a combat division

41
The AMST as currently designed is probably the least expensive

system that could meet outsize cargo requirements, if such a

capability is determined to be necessary.

Funding for procurement of the AMST was deleted from the

fiscal year 1979 budget, following a determination by the Secretary of Defense that the cost of procuring a fleet of AMSTs

large enough to satisfy assumed tactical airlift requirements

was not justified by those requirements. 35/ Nonetheless, $5

million is provided in the fiscal year 1980 budget submission for

continued evaluation of the aircraft. The procurement cost

for a fleet of AMSTs was estimated to be $8.3 billion in fiscal

year 1980 dollars.

The decision to terminate AMST procurement reflects an

assessment that the current tactical transport fleet can meet

wartime requirements and that future tactical airlift will be

limited to air resupply of bulk and oversize cargo and troops,

rather than a unit move of combat troops and their equipment.

The Air Force, however, continues to argue that future tactical airlift operations will require procurement of a widebody transport like the AMST. 36/ It should be noted that

replacement of C-130s with newer models would limit tactical

costs slightly more than $1 billion. With comparable

expenditures over time (lifetime costs for the AMST and for

the combat division could conceivably narrow substantially),

which would make the greatest contribution to the security of

NATO?

35/ Central to the debate on the AMST was the Army's stated

requirement to move outsize cargo by tactical airlift,

since the C-130 cannot transport outsize cargo. That requirement is based on two specific needs: the need to

replace equipment lost during combat and the need to move

entire combat units and their equipment, much of which is

outsize. DoD has acknowledged the potential need for tactical airlift of outsize cargo but apparently has not accepted the claim that the need is as urgent as the services

seem to believe.

It is unlikely that this disagreement will be resolved, since

it is more a function of the assumptions of the proponents

than of their calculations.

42
transport capability at the turn of the century to operational

capabilities of the 1960s. 377

Strategic Airlift Augmentation by Tactical Transports. A

major theme to emerge from the debate on tactical airlift modernization is the role of tactical transports in supplementing strategic airlift operations. In the opening days of a deployment,

before battlefield airlift requirements begin, tactical transports

would be available to supplement strategic transports. Use of the

C-130 for deployment operations could potentially improve delivery

rates by 11 percent for an airborne or infantry division, as can

be seen in Table 10. Closure time improvement is much smaller

for heavier divisions, since the C-130 cannot transport outsize

cargo, which comprises a major portion of the cargo of a heavy

division. This can be contrasted with closure time improvement

produced by AMST augmentation. Since the AMST can transport

outsize cargo, delivery rates improve by from 16 to 18 percent

for all types of divisions, including heavy divisions. 38/

Delivery rates show a dramatic improvement if the AMST supplements

strategic transports that have been improved through the C-141

stretch and CRAF modification programs, as shown in the bottom

line of Table 10.

The primary factor limiting strategic augmentation is the

relatively short range of tactical transports. This can be

compensated for either by frequent ground refueling (called

"island-hopping") or by aerial refueling. 39/ The AMST has a

37/ While Army equipment is becoming larger and heavier, it

is not certain that every piece of Army equipment—or, for

that matter, most of it—must be transported by tactical

airlift.

38/ While the AMST can transport outsize cargo, its range

decreases substantially with very heavy payloads. When

carrying the M-60 tank, for example, the AMST is limited

to a range of less than 700 miles, which is a major limitation in long-distance operations.

39/ Either option has unique limitations. Ground refueling

could cause congestion problems at intermediate bases.

Aerial refueling would impose additional requirements on a

tanker force that might have more pressing duties in the

early days of a mobilization.

43
TABLE 10. CLOSURE TIMES AS A FUNCTION OF TACTICAL TRANSPORT

AUGMENTATION

Delivery Rate by Type of Division a/

82d Hypothetical Hypothetical

Airborne Infantry Mechanized

Current Airlift/

No C-130 Augmentation _b/ .50

Current Airlift/

C-130 Augmentation cj .55

Current Airlift/

AMST Augmentation A] .58

Improved Airlift/

AMST Augmentation e/ .76

.40

.45

.48

.62

.32

.33

.38

.48

SOURCE: See Appendix A.

aj Expressed in thousand miles of distance per day for each type

of division. For example, ".50" for the 82d Airborne Division

indicates that, for each day of delivery time permitted, the

division can be transported approximately 500 miles.

b/ All organic planes flown at wartime utilization rates; full

GRAF Stage III augmentation.

c/ Same as above, though with augmentation by 218 C-130s.

dj Same as a/, plus augmentation by 141 AMSTs. The number of

AMST transports was calculated to provide equal bulk transport

capacity as provided by a fleet of 218 C-130s in theater

operations. It is assumed that the number of AMSTs would be

determined by tactical transportation requirements. Hence,

AMST fleet size is assumed to equal C-130 fleet size on the

basis of bulk capacity. The C-130 can transport only bulk and

oversize cargo; the AMST can transport outsize cargo as well.

.§/ Improved system assumes implementation of the C-141 stretch

program and the addition of 65 B-747 aircraft under the GRAF

modification program.

44
clear advantage over the C-130 in that it can be refueled aerially

and has a greater range and payload than the C-130. The primary

advantage of the AMST, however, is its capacity to transport

outsize cargo.

As is the case with other airlift improvement alternatives,

tactical airlift modernization proposals should be evaluated in

the context of alternative enhancement programs, consistent with

underlying assumptions about future airlift requirements. This

question is examined more directly in Chapter IV.

45

CHAPTER IV. ALTERNATIVE AIRLIFT FORCES FOR THE FUTURE

Military airlift is a valued element of the U.S. conventional force structure. It is also expensive. Any decision

to increase airlift capabilities must balance cost considerations against assumed requirements for airlift in the future.

In considering the fiscal year 1980 defense budget, the Congress will decide on several airlift improvement programs. In

choosing among the alternatives, it will have to address two

questions:

o What types of contingency requirements should guide

airlift improvement, and what amount of enhancement is

needed?

o What margin of flexibility should be maintained in the

future airlift system to meet those requirements?

Different contingencies suggest different criteria for

assessing airlift improvement. If the Congress evaluates airlift

improvement in terms of the NATO reinforcement requirement, the

extent of airlift improvement and the types of programs needed

would differ from those that would be appropriate for non-NATO

contingency requirements.

AIRLIFT IN A NATO/WARSAW PACT WAR

Reinforcement Objectives and Airlift Improvement Requirements

Reinforcing NATO in the face of a Warsaw Pact attack could

potentially present the most demanding requirement for military

airlift. Reinforcement objectives call for a doubling of inplace ground forces within 10 days of mobilization and delivery

of at least 1,300 tactical fighter aircraft within one week. _!/

Currently, the equivalent of five divisions is deployed in

I/ U.S. Department of Defense, Annual Report, Fiscal Year 1980,

pp. 47, 201.

47
Europe. 2] Equipment for two U.S.-based divisions is now stored

in Europe under the POMCUS program. _3/ The Department of Defense

has proposed to pre-position equipment for three more divisions

in Germany. If this proposal is implemented, a total of five

division sets of combat equipment and supplies would be in place

by the end of fiscal year 1982. In wartime, airlift would be used

primarily to transport troops and that small portion of equipment

that would not be pre-positioned. kj

While airlift would play an important role in any NATO

reinforcement operation, it must be supplemented by advanced

positioning of combat equipment if DoD's reinforcement objectives are to be met. As Table 11 indicates, if no equipment

was pre-positioned and airlift was the sole means of reinforcement, it could take as many as ten weeks to transport

five mechanized divisions, together with their unit and support equipment, from the continental United States to Europe. 5_/

If, on the other hand, equipment was pre-positioned for three

divisions and airlift was required to transport only two divisions, deployment would take approximately one month. By contrast, if equipment for five divisions and their support units

was pre-positioned, transportation time could be reduced to

approximately two days. Nearly five days would be required

to transport the equivalent of 55 tactical fighter squadrons.

2_/ Four armored or mechanized divisions and two armored cavalry

regiments are located in Germany. Three brigades, formally

assigned to the divisions currently in the POMCQS program, are

also deployed in Europe. See Ibid., p. 140.

_3/ See Chapter 1, footnote 4 for a discussion of the POMCUS

question.

kj Those items not pre-positioned in Europe generally consist

of a limited number of very expensive items (computers,

for example), or combat equipment difficult to maintain

(helicopters), or equipment that is transported by the

individual troops themselves, such as small arms and personal gear.

_5_/ Obviously, airlift would never be the only transportation

source available. Sealift would begin to carry the largest

proportion of cargo after the first month of mobilization.

48
TABLE 11. TIME REQUIRED TO DELIVER FIVE MECHANIZED DIVISIONS AND

55 TACTICAL FIGHTER SOUADRONS TO EUROPE, ASSUMING

DIFFERING LEVELS OF PRE-POSITIONED EQUIPMENT a/

Days to Deliver Forces

Current Airlift b Improved Airlift c/

No Pre-positioning 68.1 68.1 d/

Equipment for Three

Divisions Pre-positioned/

Airlift of Two

Divisions Required ej 27.6 27.6 d/

Equipment for Five

Divisions Pre-positioned/

Residual Cargo

Airlift Required 2.1 1.6

55 (Equivalent)

Tactical Fighter

Squadrons 4.2 3.2

SOURCE: Calculated from public planning factors. See Appendix A.

a/ Cargo includes unit equipment of the divisions and support

units (see Appendix A). These calculations assume that 95

percent of bulk and oversize cargo and 99 percent of outsize

cargo in combat and support units is pre-positioned.

_b/ Organic transports at programmed utilization rates; full CRAF

augmentation; strategic augmentation by C-130s.

cj Enhancement includes C-141 stretch and CRAF modifications

~ equivalent to 65 additional B-747s in CRAF.

d/ Delivery time paced by arrival of outsize cargo, which is not

affected by improvement programs.

e/ In actual practice, equipment for three and one-third divisions has been pre-positioned or will be in place by the end

of fiscal year 1980. For consistency, however, calculations

are limited to five hypothetical mechanized divisions.

49
These are very general calculations, 6/ and they consider

transit time only. Additional time would be required after

arrival in Europe for troops to draw equipment from storage sites

and move to assembly areas. In light of these calculations,

several observations can be offered. First, without advanced

positioning of unit and support equipment for ground forces, DoD's

NATO reinforcement objectives could not be met. If equipment was

not pre-positioned, airlift enhancement programs would offer only

insignificant improvement in reinforcement performance. The

improvement programs would, however, mean that bulk and oversize cargo could be delivered sooner. Since there would be no

increase in outsize cargo airlift capacity, however, overall

closure time would remain unchanged.

Second, current airlift capabilities—without enhancement—

would be sufficient to meet the ten-day reinforcement objective

set for Army units by the Department of Defense so long as unit

and support equipment was pre-positioned. A division requires

four or five days after arrival in Europe to draw its equipment

and move to assembly areas. Thus, the last units would have to

arrive on the fifth or sixth day of mobilization in order to meet

the ten-day objective. Current airlift resources are capable of

meeting this deadline.

Third, demand on airlift resources would be greatest during

the first week of mobilization, since ground combat units are

expected to be delivered within ten days and tactical fighter

squadrons within seven. Because two or three days of the first

week would be needed to transport cargo for ground units, it is

doubtful that all tactical fighter squadrons, which require four

or five days to transport, could be delivered by the end of the

seventh day. !_/ Given current airlift resources, some tactical

fighter units would arrive after the DoD objective deadline.

The airlift enhancement program, while not necessary for

meeting DoD's reinforcement objectives for ground forces, would

6/ See Appendix A for method used to compute calculations

presented in the study.

l_l It is probable that several days would be required to mobilize

the entire airlift system in an emergency. Some GRAF planes

would have to return to the United States; planes undergoing

maintenance might take several days to be repaired.

50
potentially ensure that tactical fighter squadrons could be

delivered to Europe by the seventh day after mobilization.

It might also be possible to meet the seven-day delivery objective for tactical fighter squadrons if the ten-day delivery

objective for ground forces was relaxed by a day or two. It

should be noted, however, that these dates are planning objectives, even though they are frequently framed as "requirements." &_/ The current airlift system appears capable of largely

meeting those objectives, as long as pre-positioning of combat and

support equipment continues as proposed by the Department of

Defense. Thus, if the justification for airlift improvement

programs is limited to NATO reinforcement objectives, it is

questionable whether further improvements to airlift resources are

necessary.

Flexibility of the Airlift System in a NATO/Warsaw Pact War

The capability of the current airlift system to meet the

demanding objectives of a NATO/Warsaw Pact war is the product of

several factors unique either to the European environment or to

the U.S. political commitment to the NATO alliance.

The European Environment. The facilities needed to sustain

major air transit operations in a NATO/War saw Pact war are abundant. A large number of European airports are capable of supporting massive airlift operations. _9_/ Similarly, the distance

between Europe and the United States would permit relatively high

payloads. For example, Dover Air Force Base is 3,540 nautical

8/ The two delivery objectives are derived from sophisticated

mobilization models that are based on plausible assumptions

and estimates of Soviet capabilities and intentions. It is

impossible to predict the outcome of a battle if 90 percent,

100 percent, or 110 percent of the ground forces expected

to be in Europe on the tenth day were indeed there. What can

be said is that it is better to have 100 percent than 90

percent, or 110 percent than 100 percent. None of these

numbers can be considered a "requirement," though each can be

considered an "objective."

JL/ See discussion on p. 16. There is concern about airport

vulnerability and congestion, however. Both questions are

currently being studied by DoD.

51
miles from Frankfurt, Germany. At that distance, the C-5 can

carry approximately 86 tons and the C-141 about 32 tons, permitting relatively high utilization of maximum payloads, without

intermediate refueling.

Political Commitment to the NATO Alliance. Perhaps of

greater importance are the political considerations that would

play a substantial role in any NATO contingency. The U.S.

commitment to defend Western Europe in the face of a Soviet

attack is firm. A war between NATO and the Warsaw Pact is,

perhaps, the only contingency in which an American response

with combat forces is certain. This political commitment has

several important ramifications for airlift operations. It

ensures that no administrative or financial constraints would

limit the number of military transports that could fly or the

number of hours a day they would operate. It assures that there

would be a full mobilization and that reserve manpower resources

would be available to join active-duty forces. A national emergency declaration would also guarantee that civilian aircraft

would be available. Finally, a NATO war would remove peacetime

environmental or political restrictions on airlift operations in

allied countries.

These factors have a direct effect on airlift operations.

The full range of civilian and organic aircraft would be available

in a NATO/Warsaw Pact war. Organic transports could be flown at

wartime utilization rates. Civilian aircraft, which are restricted to the relatively sophisticated facilities of modern

airports, could operate at high efficiency. In short, those

features of the existing airlift system that could potentially

prove most constraining in more limited contingencies would not

appear to be serious problems in a NATO war.

Tactical (Intratheater) Airlift in a NATO War

The decision by the Administration to delete procurement

funds for the Advanced Medium Short-Takeoff-and-Landing Transport (AMST) was based on an evaluation of the aircraft's potential contribution in a NATO conflict. The performance advantages of the AMST over the existing C-130 were not considered

by the Secretary of Defense to be sufficient to justif y its

cost. The primary factor contributing to the decision was that

Europe possesses a sophisticated and redundant local transportation system that would permit "surfac e transportation to

compete favorably with the speed and responsiveness of tactical

52
airlift." 10/ Only if that network suffered enormous damage would

the AMST be required to supplement ground transportation of

outsize cargo. It is reasonable to assume that airfields would

suffer similar damage, however, jeopardizing the conduct of

all airlift operations. Nor would the AMST appear to be justified

as a means of improving strategic airlift capacity. Table 12

indicates that, when full pre-positioning is pursued, the contribution of AMST augmentation would be negligible. Moreover, as

is the case with other airlift enhancement programs, the AMST

could not meet reinforcement objectives in the absence of advanced

equipment positioning.

TABLE 12. CURRENT AND IMPROVED TACTICAL TRANSPORT CONTRIBUTION

TO THE TIME REQUIRED TO DELIVER FIVE DIVISIONS AND

55 TACTICAL FIGHTER SQUADRONS TO EUROPE, ASSUMING

DIFFERING LEVELS OF PRE-POSITIONED EQUIPMENT

Days to Deliver Forces

Current With AMST

(Includes C-130s) (No C-130s)

No Pre-positioning/

Five Mechanized

Divisions Airlifted 68.1 58.8

Equipment for Three

Divisions Pre-positioned/

Two Divisions Airlifted

Equipment for Five

Divisions Pre-positioned/

Residual Cargo Airlifted

55 (Equivalent) Tactical

Fighter Squadrons

27.6

2.1

4.2

24.7

1.9

3.9

SOURCE: See Appendix A.

10/ U.S. Department of Defense, Annual Report, Fiscal Year 1980,

p. 210.

53
AIRLIFT IN A MIDDLE EAST/PERSIAN GULF CONTINGENCY

The Department of Defense has considered it prudent to

plan for the concurrence of a major war and a lesser contingency.

The "one and one-half war" strategic concept represents both a

planning artifact and a reasonable (though conservative) assessment of actual situations that might develop in the future.

During most of the 1960s and early 1970s, the most demanding

"minor" contingency for planning purposes was the defense of

South Korea against an attack by North Korea supported by either

China or the Soviet Union. More recently, and certainly since the

Arab-Israeli war in 1973 and the emergence of the politics

of petroleum, a conflict in the Persian Gulf or Middle East

regions has supplanted Northeast Asia as the "minor contingency"

for force planning purposes, ll/

One of the inherent difficulties associated with force planning for a minor contingency is the absence of a consensus as to

the nature of a possible conflict and the threat posed to American

interests. With respect to a NATO/Warsaw Pact war, there is

general agreement concerning the probable factors associated with

a Warsaw Pact attack—its possible size, probable military objectives, plausible invasion routes, and so on. No comparable

agreement exists regarding a Middle East/Persian Gulf contingency.

All planning contingencies share a common theme, however: American forces would be deployed to a region to assist a friendly

power defend itself against an attack by a neighbor supported by

Soviet forces. The Secretary of Defense has indicated that a

force consisting of several Army divisions, Marine amphibious

forces, and several air wings could be required in such a circumstance. 12/ Table 13 presents relative delivery times required

for various divisions in a deployment to the Persian Gulf. With

ll/ While Korea continues to be a focus of contingency planning,

developments in Northeast Asia have contributed to its

decline as the "limited contingency" for force planning. See

Congressional Budget Office, Force Planning and Budgetary

Implications of U.S. Withdrawal from Korea, Background Paper

(May 1978), pp. 7-12.

12/ Statement of Secretary of Defense Harold Brown in Department

of Defense Authorization for Appropriations for Fiscal

Year 1979, Hearings before the Senate Committee on Armed

Services, 95:2 (February 1978), Part 1, p. 100.

54
TABLE 13. TIME REQUIRED TO DELIVER COMBAT UNITS TO THE PERSIAN

GULF AREA WITH VARYING AIRLIFT RESOURCES, BY TYPE OF

DIVISION

Days to Deliver Forces

82d 101st Hypothetical

Airborne Airmobile Mechanized

Full Organic/Full GRAF a/

Full Organic/No CRAF

Organic Lift/No CRAF/

C-141 Stretch

Full Organic/

C-141 Stretch/

CRAF Stage I

Full Organic/

C-141 Stretch/

CRAF Stage I/

AMST Augmentation cj

13.4

18.7

17.4

14.9

13.9

12.9

18.0

16.7

14.4

13.3

22.1 b/

27.6

25.7

22.1

20.6

SOURCE: See Appendix A.

aj Includes full CRAF mobilization and augmentation by C-130s.

_b/ Closure is limited by pace of outsize cargo deliveries,

c/ Excludes any C-130 augmentation.

current airlift resources, it could take as long as 26 days to

deploy the two lightest divisions in the Army—the 82d Airborne

and the 101st Airmobile—to the Persian Gulf. If both a light and

a heavy division were to be deployed, closure times could potentially reach five weeks. Small elements of the 82d Airborne Division could be delivered within two days, though their contribution

would be more political than military until the remainder of the

force had arrived.

55
Flexibility of the Airlift System in a Persian Gulf Contingency

Since there is no firm agreement as to the nature of a

military threat in the Persian Gulf region, no reinforcement

objectives have been set against which the adequacy of existing

airlift resources can be measured. As Table 13 indicates,

however, it could take as long as five weeks to deliver a light

and a heavy division to the Persian Gulf region by airlift alone,

assuming that all airlift resources were available for the deployment. The existing airlift system might not be uniformly available, however.

A demanding Persian Gulf contingency assumes Soviet involvement. Should such a situation precede a NATO/Warsaw Pact

war, many factors could combine to limit airlift operations.

In such a political climate, it is questionable that a declaration

of national emergency, necessary for a full CRAF mobilization,

would be made, since such an action could potentially send

unacceptable signals to the Soviet Union. Since it is probable

that the President would want to insulate a Persian Gulf contingency to prevent escalation into a NATO/Warsaw Pact war,

•it is probable that he would avoid mobilization (or delay its

announcement), thereby limiting the amount of civilian reserve

aircraft available for a Persian Gulf deployment. Also, as

has already been noted, mobilization of CRAF would disrupt

the domestic economy, which the President would probably want

to avoid except in the most severe emergencies. Table 13 indicates that, if no CRAF planes were available for airlift

operations, it could take as many as 10 additional days to

deliver a two-division force. It is possible that the Department

of Defense would resort to a limited civilian reserve mobilization. This, in combination with the C-141 stretch program

(line four of Table 13), would improve delivery times substantially, though not as much as would a full mobilization of the CRAF

fleet. Further augmentation by the AMST would offer additional

improvement, especially for heavy divisions.

It is important to note that major procurement of new

organic planes would be required to reduce delivery time substantially. Table 14 indicates that it would take a very large

procurement of new aircraft—as many as 400 AMSTs or 100 new

C-5s—to reduce closure times by a week for one division or

two weeks for a two-division force. Such procurement produces

substantial improvement in delivery times, particularly for heavy

divisions.

56
TABLE 14. IMPROVED DELIVERY RATES TO PERSIAN GULF WITH AMSTs OR

ADDITIONAL O5s, BY TYPE OF DIVISION

Days to Deliver Forces

82d

Airborne

101st

Airmobile

Hypothetical

Mechanized

Organic Lift/

C-141 Stretch/

GRAF Stage I/

C-130 Augmentation aj

With 141 AMSTs _b/

With 277 AMSTs c/

With 400 AMSTs

14.9

13.9

12.1

10.8

14.4

13.3

11.5

10.3

22.1

20.6

18.0

16.2

or

With 50 C-5s

With 100 C-5s

11.7

9.7

11.4

9.4

17.5

14.5

SOURCE: See Appendix A.

aj Additions of AMST transports supplant C-130 aircraft.

JV 141 AMSTs produce approximately the same bulk cargo capacity

in tactical airlift operations as the 218 C-130s used in the

base estimate. (See Table 10 in Chapter III.)

c/ The previous Air Force proposal for AMST procurement.

While CRAF unavailability would be the major complication for

airlift operations in a non-NATO contingency, additional problems

might be anticipated with organic transports. The delivery rates

in Tables 13 and 14 assume that organic aircraft would be flown

at wartime utilization rates. Over the course of a Persian Gulf

deployment, this would substantially deplete reserve inventories

of spare parts. Since a deployment to the Persian Gulf would be

accompanied by a continuing possibility of conflict in Europe,

57
flying rates might be held down in order to avoid consumption of

spare parts in anticipation of a major NATO airlift operation.

These factors present an airlift contingency requirement

substantially different from that posed by a NATO/Warsaw Pact

war. Civilian reserve assets might not be available for a

Persian Gulf contingency, or at least not at full GRAF Stage III

levels. Administrative constraints might impose flying limits

on organic transports. While there are no clear objectives by

which the need for additional airlift resources can be evaluated,

airlift programs that improve the capacity of organic transports

could help compensate for the questionable availability of

civilian augmentation.

Tactical (Intratheater) Airlift in a Persian Gulf Contingency

The ground transportation network in the Middle East and

Persian Gulf areas is not nearly as sophisticated or redundant

as is the European network. Thus, tactical airlift could be

expected to play a larger role in battlefield logistics in a

Persian Gulf contingency than it would in a NATO war. A tactical

transport like the AMST would have important advantages over

the C-130, since it could transport outsize cargo and operate on

shorter runways. DoD analysts have recognized this potential

contribution, though they evidently have concluded that it is

not feasible to procure a major weapon system that is not justified primarily by its utility in a NATO/Warsaw Pact war.

Also, as Tables 13 and 14 indicate, a major procurement of AMSTs

would be required in order to make a substantial contribution to

delivery schedules if used for strategic augmentation.

ALTERNATIVE AIRLIFT FORCES FOR THE FUTURE

Congressional decisions concerning airlift improvement

programs this year will affect the structure, capabilities,

and system flexibility of airlift forces for many years to come.

Naturally, the Congress will want to ensure that airlift forces

are capable of meeting future requirements. Three alternative

approaches might be considered:

o The Congress could assume that the defense of NATO is

the only plausible or compelling contingency to be

expected in the future and that airlift improvement

programs should be justified strictly in terms of their

58
potential contribution to meeting NATO reinforcement

objectives. The corollary assumption is that all future

non-NATO contingencies would require less airlift than

a NATO war.

o Alternatively, the Congress could assume that current

airlift forces, while adequate for operations in a NATO

conflict, would be significantly constrained in a non-NATO

contingency. It might then wish to approve enhancement

programs that were designed to compensate for those

constraints.

o Finally, the Congress could conclude that airlift resources will be relied on more heavily in the future as

the primary means of rapidly projecting American combat

forces abroad. Given that assumption, procurement of

additional organic aircraft would be necessary. This

proposition rests on the assumption that future requirements for airlift would rarely allow as much preparation

and execution time as current airlift forces require.

With greater airlift capabilities, more time could be

devoted to evaluating developments and directing military

responses. Further, since events rarely unfold as expected, improved airlift would provide a crucial element

of flexibility.

These three perspectives suggest alternative options regarding

airlift improvement programs before the Congress.

Airlift Improvements to Meet NATO Reinforcement Objectives

If airlift improvement programs were designed to meet NATO

reinforcement objectives only, the Congress would be concerned

primarily with finding the least expensive means to store wartime

airlift capacity. The following choices would be best suited

to meet this objective.

The C-5 Wing Modification Program. It would be feasible to

adopt a modification program that extended the service life of the

C-5 for fewer than the 30,000 hours requested by the Department

of Defense. A NATO reinforcement deployment of five mechanized

divisions could consume approximately 900 service-life hours,

less than one and one-half years at current peacetime utilization

rates. With pre-positioning of combat equipment in Europe, only a

limited amount of outsize capacity would be required. A limited

59
fastener change on the C-5, in conjunction with slightly lower

peacetime utilization rates, would extend the useful life of the

plane until 1995 and still permit at least one full NATO airlift

operation.

This improvement could be made for $543 million, or about

one-half the cost of the full re-winging program proposed by the

Air Force. 13/ This alternative would entail some risks, however.

Without a new wing, the C-5 could not conduct some wartime maneuvers safely, and its operations would be restricted to fewer

airports. On the other hand, it is doubtful that the C-5 would

ever operate under the conditions originally envisioned for it.

Administrative prudence and a desire to protect so expensive a

plane would probably limit some types of missions, even with a new

wing. It should also be noted that the Department of Defense

would face a difficult decision about employing the C-5 for minor

contingencies because it could potentially reduce eventual capacity of the plane to respond safely to a future NATO deployment

requirement. If, on the other hand, one assumed that no contingency would emerge that would make such substantial demands—or

that, if one did, it would probably evolve into a general war in

Europe—then such constraints might be acceptable in light of the

substantial cost savings.

The C-141 Stretch Program. The improvement in delivery rates

produced by stretching the C-141 is small. Termination at this

point would save the $269 million required to finish the program,

less any penalties associated with such a cancellation. However,

terminating the stretch program would also involve cancelling the

installation of aerial refueling capability in the aircraft.

At this point, it is unclear how much of the possible savings

would be consumed by just installing aerial refueling—which is of

great potential value in certain limited contingencies.

The GRAF Modification Program. The CRAF modification program

is clearly the least costly way to increase airlift capacity. If

evaluated in the context of the NATO reinforcement requirement,

however, the modification program might not be necessary, assuming

that equipment is pre-positioned for all the divisions and support

units that are expected to be in Europe by the tenth day of

CBO update of a Rand Corporation estimate of the cost of a

fastener change, adjusted for inflation and incorporating

some items not included by Rand.

60
mobilization. As noted above, current reinforcement objectives

for ground forces could be met without improving current airlift

resources if DoD's pre-positioning program was implemented.

Delivery of tactical fighter squadrons to Europe within a week,

which is currently problematical, could be assured if the GRAF

modification program was implemented. That objective might also

be met, however, if ground forces delivery schedules were relaxed

by a day or two. The Congress might want to question whether the

one- or two-day improvement in meeting a planning objective that

the GRAF modification program would provide is worth the estimated

$550 million cost of achieving that capability.

Tactical Airlift Modernization. If the Congress decides that

a NATO war should guide tactical transport modernization, procurement of the AMST does not appear warranted, either for battlefield

mobility or for strategic augmentation. If, however, a decision

is made not to procure the AMST, continued procurement of the

new C-130 (model H) would be necessary to replace older models.

This replacement of old C-130s would cost $2.1 billion.

Airlift Improvements to Meet Limited Contingency Objectives

The primary concern of an airlift improvement program designed to meet future limited contingency objectives is to overcome potential limitations in the existing airlift system.

The C-5 Wing Modification Program. If non-NATO contingencies

guide airlift improvement, a 30,000-hour service life would be an

important goal for the C-5 wing modification program. Since no

equipment is currently pre-positioned for U.S. forces outside

the NATO region, the C-5 would be more vital to the conduct of

operations in a non-NATO contingency than it would be in a

NATO conflict. Perhaps of greater value, a full wing modification

program would remove the performance restrictions that currently

limit C-5 operations. With full modification, the C-5 could

routinely operate on shorter runways with heavier payloads. Such

performance might be crucial in limited contingencies in areas

such as the Persian Gulf. The C-5 re-wing program would cost

$1.1 billion.

The C-141 Stretch Program. As with the C-5 modification

program, the C-141 stretch program should continue in order to

meet the requirements of non-NATO contingencies. The added airlift capability of the C-141 would be useful in limited contingencies in which full CRAF augmentation might not be guaranteed.

61
Of potentially greater significance is the addition of aerial

refueling capability, which makes this an attractive program for

meeting limited contingency objectives, since refueling stops

might be denied for political reasons. The cost of this program

would be $269 million.

The GRAF Modification Program. The CRAF modification program

suffers from the same limitations as the CRAF system itself.

Planes modified under the program would be available for airlift

operations only upon a full mobilization. While this could be

expected in a NATO/Warsaw Pact war, it is less certain in a

non-NATO contingency. Some CRAF augmentation, perhaps at Stages

I and II, would be available, however. Full mobilization is

certainly questionable, which would exclude the benefits of the

CRAF modification program.

Tactical Airlift Modernization. While the AMST presents distinct performance improvements over the C-130, it is not certain

that the current tactical transport fleet would be a bottleneck in

limited contingencies. The primary advantage of the AMST is its

capacity to transport outsize cargo and operate on short runways.

This would be a particular advantage in a Middle East contingency.

Yet, in Saudi Arabia, for example, the C-5 can operate in only

four fewer airports than the AMST, and the C-130 can operate in

virtually the same number of fields as the AMST. Further, the

potential contribution of the AMST in strategic augmentation

operations, while better than that of the C-130, would make a

relatively small difference in delivery time. Neither tactical

transport requirements nor strategic augmentation appear to

justify procurement of the AMST for limited contingencies.

The Advanced Tanker/Cargo Aircraft. The Department of

Defense has argued that the ATCA is needed primarily to satisfy

tanker requirements during limited contingencies. The performance

of the KC-10 is clearly superior to that of the KC-135, especially

on long-distance deployments such as those that would be encountered in a Persian Gulf contingency. Nonetheless, the Congress might want to assess the need for further procurement of

ATCA in light of two considerations. First, if a limited contingency did not lead to, or was not accompanied by, a reinforcement

of NATO, it appears that the current tanker force would be capable

of meeting refueling requirements. 14/ While the number of KC-135

14/ See discussion on pp. 39-40.

62
tankers required would be much larger—and less efficient—than a

comparable force of KC-lOs, the requirement could be met. Second,

procurement of an advanced tanker for strategic airlift has been

justified most strongly on the basis of the experience of the Israeli airlift in 1973, during which intermediate ground refueling

was in question and overflight rights were denied. This could be

a possibility again in the event of an Arab-Israeli war. It is

difficult to imagine comparable developments elsewhere, however.

Thus, it appears that the justification for ATCA rests almost

exclusively on its potential application in a Middle East/Persian

Gulf contingency, for that is the one clear circumstance in which

existing tanker resources might be committed to a more pressing

set of requirements (for example, keeping the strategic bomber

force at highest readiness) and in which intermediate refueling

bases might be denied to airlift operations. The value of the

ATCA would not be nearly so significant in other limited contingencies, such as the reinforcement of South Korea. In light of

significant political changes in the Middle East/Persian Gulf

region, the Congress could forego further ATCA procurement at this

time, especially since the program involves adapting a commercial

airplane that will be in production well into the 1980s.

An Expanded Airlift System for Limited Contingencies

If the Congress decides that airlift forces should be

able to deliver combat units faster in future contingencies than

is currently possible, it would have to procure more organic

transports. The C-141 stretch and GRAF modification programs

would improve delivery times for lighter units but not for

heavier units, which have no combat equipment pre-positioned. 15/

Further, since GRAF availability might be uncertain in future

non-NATO contingencies, procurement of additional organic aircraft

would provide the most assurance that future airlift forces would

be able to respond to demanding airlift requirements in those

situations.

Current outsize cargo capacity limits overall delivery

time for heavier divisions. Further, no GRAF planes can carry

outsize cargo. To shorten delivery times, any airplane added to

the fleet should be capable of carrying outsize cargo.

15/ See Table 9, p. 34.

63
Two substantially different alternatives—procurement of the

AMST or of additional C-5s—might be considered. 16/ If the

Congress is interested primarily in improving strategic airlift

forces at the least cost, procurement of additional modified C-5

transports would be the preferable alternative. Table 14 indicates that 50 additional C-5s would achieve a greater improvement

in delivery time than a fleet of 277 AMSTs. At a cost of $92 million for each C-5 modified transport, a fleet of 50 C-5s would

cost $4.6 billion, compared to $8.3 billion for 277 AMSTs.

If 50 new C-5s were procured, only a limited fastener

change on existing C-5 aircraft would be necessary to ensure

continued operation of the fleet. The new C-5s could absorb the

flying hours required to maintain training for the air crews of

all 120 C-5s, thereby conserving service life of the older C-5s.

Alternatively, the Congress could choose to expand current

airlift capabilities by modernizing the tactical transport

fleet with procurement of the AMST. A fleet of 277 AMSTs would

cost $8.3 billion, though $2.1 billion would be saved if no

replacement C-130 transports were ordered. The primary advantage of AMST procurement would be an improvement in tactical

capabilities for operations in regions such as the Middle East

in which local transportation networks might be limited. The AMST

could not achieve the same efficiency as the C-5 in the strategic transport role, however. The C-5, on the other hand, would

not improve tactical transport forces.

It should be noted that both the C-5 and the AMST are currently being evaluated by the Department of Defense as possible

delivery vehicles for future ICBM missiles and air-launched cruise

missiles. Each plane has advantages and disadvantages for these

purposes. The C-5 could potentially carry two ICBM missiles,

substantially reducing the number of planes—and thereby the

procurement and operating costs—of this type of airborne ICBM

system. The AMST would be able to transport only one ICBM.

The C-5 could potentially carry 64 cruise missiles, whereas the

AMST—as currently designed—could hold only 16. The AMST would

16/ The B-747 could be modified to enable it to carry outsize

cargo. The Boeing Corporation, manufacturer of the B-747,

has received substantial orders for its new wide-body

intermediate range aircraft, potentially limiting its

ability to manufacture many B-747s quickly.

64
have a distinct advantage over the C-5 since it could take off and

land from thousands of U.S. airports, whereas the number of

airports capable of accommodating the C-5 would be substantially

lower. Further, if the airmobile missile was expected to be able

to survive for a number of days or weeks, the AMST would have a

distinct advantage over the C-5 in that it could be shuttled from

airport to airport, thus lessening the chance that it could be

destroyed on the ground by enemy attacks.

Procurement of either aircraft as a strategic delivery

vehicle for missiles would have direct implications for airlift

improvement. If either the C-5 or the AMST was procured as both

an organic transport and a strategic missile delivery vehicle,

unit costs could be reduced substantially as a result of a larger

production run. 17/ Since the outcome of the DoD evaluation has

not yet been announced, the AMST and C-5 options are presented

here merely as alternatives, although a decision to procure either

of them for strategic nuclear missions would have a substantial

effect on their cost.

SUMMARY

Table 15 summarizes the programs and costs associated with

each of the airlift improvement alternatives discussed above.

They are not strict alternatives in that procurement programs in

the expanded airlift category could be combined with enhancement

programs for NATO reinforcement or limited contingencies. It is

important to note, however, that decisions made by the Congress

for fiscal year 1980 will determine the structure and capabilities

of airlift forces for many years to come. The range of expenditures presented in Table 15—from $2.9 billion to $9.6 billion—

indicates that airlift enhancement could be an area in which

defense expenditures could be reduced or increased, depending on

what the Congress anticipates to be the need for airlift forces in

the future.

17/ Each of the first 50 C-5s purchased would cost $92.1 million.

The average cost of the next 50 C-5s is estimated to be $61.3

million. Similarly, the average cost of the first 277 AMSTs

is $29.8 million, while the average cost of the next 100 is

$13.4 million.

65
TABLE 15. ALTERNATIVE AIRLIFT FORCES FOR THE FUTURE: IN MILLIONS OF FISCAL YEAR

1980 DOLLARS

Fiscal Total Program Costs

Year (Fiscal Year 1980

Alternative Airlift Forces 1980 and Beyond)

Department of Defense Program Baseline af

Full wing modification of C-5s ~ 91

CRAF modification program 74

C-1A1 stretch program 130

KC-10 Advanced Tanker/Cargo Aircraft 190

Replace 208 C-130 models A/B/D with model H 202

Total, DoD Baseline 687 4,760

NATO Reinforcement Airlift Force

Fastener change on existing C-5s 90

Replace 208 C-130 models A/B/D with model H 202

Continue C-141 stretch program 130

Total, NATO Reinforcement 422

Limited Contingency Airlift Force

Full wing modification of C-5s 91 1,087

Replace 208 C-130 models A/B/D with model H 202 2,096

Continue C-141 stretch program 130 269

Total, Limited Contingency 423 3,452

Expanded Airlift Force

Enhanced strategic airlift force

Procurement of 50 new C-5s 30 4,604

Fastener change on existing C-5s 90 543

Replace 208 C-130 models A/B/D with model H 202 2,096

Continue C-141 stretch program 130 269

Total, Enhanced Strategic Force 452 7,512

Enhanced tactical airlift force

Procurement of 277 AMSTs 5 8,256

Full wing modification of C-5s 91 1,087

Continue C-141 stretch program 130 269

Total, Enhanced Tactical Force 226 9,612

aj The Department of Defense baseline includes those programs listed in the

fiscal year 1980 posture statement. Since DoD has no current plans for

tactical airlift modernization, CBO has selected the least expensive option

(that is, replacement of 208 C-130 models A/B/D with new model H) for inclusion in the baseline airlift force.


APPENDIX A. ASSUMPTIONS AND METHODOLOGY USED IN AIRLIFT

CALCULATIONS

This appendix serves two purposes. First, it introduces

the reader to the factors that are relevant to mobility planning calculations. Second, it substantiates the conclusions

offered in the text of the paper. Planning variables fall

into three categories: those specific to the means of transportation (aircraft variables); the cargo transported (cargo

variables); and the routing used in an operation (route variables) .

The methodology used in this paper provides a framework

for evaluating airlift operations on the basis of general performance characteristics. Throughout the calculations, basic

assumptions have been held constant so as not to prejudice

performance of any particular component of the airlift system or of the enhancement programs. All of the planning variables used in the calculations are derived from public sources.

As a result, the airlift system is evaluated on the basis of

a public methodology similar (though far less sophisticated)

to that used by the Department of Defense. This approach has

also been used in earlier CBO studies. _!/ Of course, performance

of the airlift system in a contingency may differ from the

results of these calculations, since planning factors can only

approximate the many variables that affect delivery schedules

in actual operations.

AIRLIFT PLANNING FACTORS

Aircraft Variables

Table A-l presents five major categories of variables

specific to aircraft used in these calculations. Each is described in turn.

I/ See Congressional Budget Office, U.S. Projection Forces:

Requirements, Scenarios, and Options, Budget Issue Paper for

Fiscal Year 1979 (April 1978).

69
TABLE A-l. AIRCRAFT VARIABLES USED IN COMPUTATION OF AIRLIFT

CAPACITY

Aircraft

Type

C-5

C-141

B-747

(cargo)

B-707

(cargo)

B-707

(passenger)

C-130

AMST

Utilization

Number Rate a/

70

234

17/31 _b/

30/83 b/

430 b/

218

141

12.5

12.5

10.0

10.0

10.0

8.0

8.0

Productivity

Factor Speed

.445

.445

.470

.470

.470

.445

.445

428

407

450

440

440

260

400

Payload

69.3

21.0

72.9

30.0

165.0

13.8

18.4 cj

at These are programmed utilization rates.

_b/ Expressed as equivalent units by indexing airplane characteristics to the B-707 or B-747, as appropriate for narrowbody and wide-body jets. The first number represents those

planes in CRAF Stage I; the second, full CRAF mobilization.

_c/ Payload for palletized cargo only.

Number. The number of military transports is the unit

equipment (UE) number, recently relabeled the "primary aircraft

authorization" (PAA). 2/

2/ Special attention should be given to the number used for AMST

aircraft. This study compares the C-130 and the AMST in terms

of strategic augmentation. The number of aircraft will be

70
The actual civilian fleet (CRAF) consists of many different types of planes. These types of planes are indexed

against the B-747 (for wide-body jets) and B-707 (for narrowbody aircraft), using conversion factors developed by the Military Airlift Command. 3_/ Thus, the three categories of civilian planes are expressed in terms of B-747/B-707 equivalent

aircraft.

Utilization Rate. The utilization rate is a planning

variable that expresses system-wide airlift performance for

each type of plane in terms of daily flying hours. For example, a C-5 flying a 12.5-hour utilization rate means that

over an airlift operation each plane will average 12.5 hours

of flying time a day. At any given time, only about one-third

of the planes will probably be flying but, when they are, they

will operate (discounting intermediate refueling stops) for

more than 12.5 hours at a time. A utilization rate of 12.5

hours will produce twice the potential lift for a fleet of

planes than would be produced if that same fleet were operated

6.25 hours a day.

It is important to note that the utilization rate is a

planning variable. Higher rates can be attained with greater

inventories of spare parts, more flight crews, and more maintenance personnel. Civilian airlines routinely maintain 10-

hour utilization rates. MAC plans to fly organic transports

12.5 hours a day for the initial 45 days of an airlift operation

determined by tactical airlift requirements, however, and

not by strategic augmentation requirements. Thus, the

number of AMSTs used in these calculations was selected

so that the AMST fleet and the fleet of 218 C-130s would

provide roughly equal potential airlift of bulk cargo in

tactical operations. The Air Force had actually proposed

to purchase 277 of these aircraft. Specific conversion

factors were provided by the Air Force Directorate of Concepts and Analysis.

_3/ See The Posture of Military Airlift, Hearings before the

Subcommittee on Research and Development, House Committee

on Armed Services, 94:1 (November 1975), pp. 524-28. MAC

refers to these conversion factors under the title "Mobilization Base Index."

71
and maintain 10 hours a day for the remainder of it. kj The

GRAF contract calls for 10-hour utilization rates throughout

a mobilization.

Productivity Factors. Planes that carry cargo to a destination must either return empty or return with wounded troops

or equipment for repair in the United States. In terms of

delivering a specified cargo to the theater, these return flights

are not productive. The productivity factor lowers systemwide performance to account for those actions that are "nonproductive." These numbers are specified in Air Force Regulation 76-2.

Speed. The speeds given here are technically known as

"block-in" speeds, which average the cruising speed of an aircraft with the lower take-off and landing approach speeds.

Obviously, the longer the distance of a flight, the greater the

"block-in" speed, since less time of the total flight is consumed

by take-offs and landings at lower speeds. The block-in speed

and the cruising speed become very close over distances of more

than 2,000 miles. At lesser distances, block-in speed can be

substantially lower. The speeds given in Table A-l assume a

3,500-nautical mile average distance. _5/

Payloads. The payloads presented in Table A-l were not

necessarily those used in the calculations. This is described

at greater length in the next section. They are provided here

both for purposes of comparison and to introduce discussion of

one of the most important and complicated aspects of airlift

calculations.

Any airplane can lift a given amount of weight, consisting of

the plane itself, its cargo, and its fuel. At some distance

unique to each type of plane, a direct trade-off exists between

the quantity of fuel and the quantity of cargo; to fly beyond that

distance without refueling requires increased quantities of fuel,

4/ The Air Force has reported that the C-141 could sustain a

utilization rate as high as 15 hours a day. See Military

Airlift, Hearings before the Subcommittee on Military Airlift, House Committee on Armed Services, 91:2 (January and

February 1970), p. 6713.

_5_/ Speed factors are derived from Air Force Regulation 76-2.

72
which in turn lowers the amount of lift capacity that can be

allocated to cargo. The C-5 can transport up to 104.4 tons

of cargo for a little more than 3,000 nautical miles. Beyond

that point, cargo capacity drops in relation to additional

distance flown.

The longest unrefueled distance a plane must travel on

any given trip—termed its "critical leg"—determines the payload

for the entire trip. The payloads given in Table A-l assume a

critical leg of approximately 3,500 nautical miles, except for

the C-130 and AMST, for which the critical leg distance is assumed

to be 2,500 nautical miles. 6/

Cargo Variables

The second major category of variables affecting the time

required to deliver combat forces and supporting equipment is

the cargo of the units themselves. Cargo of combat units varies

in three primary ways, as discussed below.

Gross Weight Differences. Some divisions are heavier than

others. Table A-2 gives cargo data for the five types of divisions in the Army. The types of divisions are listed in descending order from heaviest to lightest. Mechanized and armored

divisions are roughly similar in weight. The 82d Airborne and

101st Airmobile divisions also tend to be of similar weight.

Different Distributions of Cargo by Categories. Armored

and mechanized divisions are not uniformly heavier than lighter

divisions. The primary difference occurs in unit equipment

in the oversize and outsize cargo categories. Bulk cargo tends to

be relatively similar for each type of division. Similarly,

support equipment cargo tends to be relatively similar (by tonnages, although not necessarily by inventories), regardless of

division type. A heavy division takes longer to transport, not

only because it weighs more than a lighter division, but also

because more of its weight is concentrated in the outsize cargo

category, which can be carried only by the C-5.

Density Differences by Division Type. The final planning

variable associated specifically with cargo concerns the type

6/ Payload variables are found in Air Force Regulation 76-2.

73
TABLE A-2. UNIT EQUIPMENT AND SUPPORT CARGO, a/ BY TYPE OF

DIVISION: IN SHORT TONS

Division Type Bulk Oversize Outsize Passengers

Armored

Unit equipment

Support equipment

Mechanized

Unit equipment

Support equipment

Infantry

Unit equipment

Support equipment

Airborne

Unit equipment

Support equipment

Airmobile

Unit equipment

Support equipment

5,979

8,440

5,778

8,534

5,596

8,043

5,226

7,977

5,182

6,907

21,704

25,059

21,577

25,059

16,395

26,365

8,814

26,283

8,345

24,126

27,658

13,442

21,213

13,442

7,760

13,182

593

13,182

1,702

10,936

16,460

17,642

16,152

18,110

16,495

18,100

14,914

17,969

17,668

16,021

SOURCE: Information provided to CBO by U.S. Air Force.

aj The support cargo represents the "initial support increment" in previous force planning. This notion, which had

its complement in the "sustaining support increment," has

been replaced in recent years. The two support packages

are now called the "non-divisional combat support" and

the "tactical support increment." This was not merely

a change in name, but involved a shifting of the various

elements within these two packages. No unclassified data

are currently available on the new breakdown of support

units.

74
of equipment that is generally found in various units that

require air transportation. Heavier units tend to have cargo

items with greater density than lighter units, especially in the

outsize cargo category. The M-60A1 main battle tank and the

CH-47C cargo helicopter provide extreme but useful examples.

The density of the M-60 is 25.3 pounds per cubic foot. The

density of the CH-47C is 1.61 pounds per cubic foot. The tank is

more than 15 times as dense as this particular cargo helicopter.

Tanks are a major component of the cargo of heavier divisions.

Conversely, helicopters are the backbone of the 101st Airmobile

Division. As could be anticipated, Table A-3 shows that average

payloads for each type of plane tend to be greater for heavier

divisions. Cargo with greater density permits planes to fly

with higher average payloads.

Routing Variables

There are two primary routing variables: the distance to

the destination from the U.S. point of embarkation and the

"critical leg," which is the longest distance the plane must fly

without refueling. Because of the uncertainty associated with

unique routing questions, the critical leg is assumed to equal

approximately 3,500 nautical miles. At this distance, payloads are almost always limited by volume or floor space and

not because of critical distance constraints. The payloads

presented in Table A-3 were used in the calculations and reflect these limits.

COMPUTING AIRLIFT CAPACITY

Determining delivery rates for different types of units

with different airlift resources essentially involves computing

daily lift capacity for each type of aircraft, and then dividing

the cargo by the daily lift capacity to determine the days

required to deliver the units. Two separate formulas are required.

N. x U. x S. x R.

m L =

 1 1

(1) L... x * * x p P...

75
TABLE A-3. PAYLOAD PLANNING VARIABLES USED IN AIRLIFT COMPUTATIONS: IN SHORT TONS

Payload Category

Aircraft

Type

C-5 a/

C-141A c/

C-141B d/

B-747

(cargo) el

B-707

(cargo) fj

B-707

(passenger) f/

C-130 gj

AMST h/

Division Unit Equipment

Airborne

54.6

13.9

17.4

57.4

30.0

165.0

13.8

25.0

Airmobile

30.1

12.9

16.1

31.7

30.0

165.0

13.8

25.0

Infantry

68.5

17.8

20.6

72.1

30.0

165.0

13.8

25.0

Mechanized

68.5

20.8

24.1

72.1

30.0

165.0

13.8

25.0

Army Support

All Divisions

69.3

21.0

24.4

72.9

30.0

165.0

13.8

25.0

Air

All

56

17

19

59

30

165

13

25

Force

Cargo

.6 W

.2 b/

.9 b/

.6 b/

.0

.0

.8

.0

SOURCES: See below.

a_/ Air Force Regulation 76-2, p. 10.

b/ No public planning factors for Air Force payloads by type of plane are available. These

payload factors were derived by reducing respective Army support payloads by the ratio

13.4/16.4, which is the density factor for Air Force cargo divided by the density of

Army cargo. See Air Force Regulation 76-2, p. 42.

c/ Air Force Regulation 76-2, p. 13.

d/ No public planning factors are available for the stretched version of the C-141. The

Air Force has reported that payloads will vary with unit cargo density, from 25 percent

for low-density cargo to 16 percent for high-density cargo. Payloads for the airborne

and airmobile divisions are increased by 25 percent; remaining payloads are increased

by 16 percent.

el No public planning factors are available for unit equipment variances by division type

for CRAF wide-body jets. These payload variables represent the same ratio of division

equipment to Army support payloads as prevails for the C-5, for each type of division.

The support figure is equal to 75 percent of maximum allowable cabin load for the B-747.

Jr_/ Air Force Regulation 76-2, p. 14.

j»/ Information provided to CBO by U.S. Air Force (December 1978).

h/ Air Force Regulation 76-2 update for generic AMST performance.
Where

L. . = Strategic lift capacity of aircraft i_, for a

cargo of a force j_, measured in tons/day

N. = Number of aircraft i i —

U. = Utilization rate of aircraft _!_

S. = Block-in speed of aircraft i i —

R. = Productivity factor for aircraft ^_

D = Distance traveled by aircraft jL

P. . = Payload of aircraft jL, given cargo of force j_

As an example, the following presents the lift capacity of the

C-5 carrying unit equipment of a mechanized division over a

hypothetical distance of 4,000 nautical miles:

70 x 12.5 x 428 x 0.445

Daily C-5 lift = x 68.5

4,000

2,854 tons/day

Expressed verbally, a fleet of 70 C-5 transports, averaging

12.5 flying hours a day, carrying the equipment of a mechanized

division over a distance of 4,000 nautical miles could transport

2,854 tons per day. The same calculations are computed for each

of the other types of aircraft, for each division, and for the

support equipment of that division.

The next step involves computing the time required to deliver

all of the cargo of the unit and its supporting elements. The

time required to move that force may be expressed as:

77
U. + x V. - x

(2) T = -J = -J

J (U)j (V)j

Where

T. = Time in days to move force j_

U. = Outsize tonnage associated with force J_

V. = Oversize/bulk tonnage associated with

force 2.

L , . = Daily lift capacity for outsize cargo, com-

^ 'J puted from equation (1) ]_/

L. . . = Daily lift capacity for oversize/bulk cargo,

computed from equation (1). That capacity

is the sum of airlift generated by the

C-141, C-130, and CRAF B-747. 8/

and

Total oversize/bulk cargo carried in aircraft

capable of outsize cargo

It is necessary to make the following assumptions before

computing delivery time using equation (2):

o All military transports are capable of carrying bulk and

oversize cargo. Outsize cargo, however, can be carried

only in the C-5 and the AMST.

o The distance of destinations from coastal ports of embarkation is increased by 1,000 nautical miles to account for

flights originating inland.

]_/ This is essentially the capacity of the C-5 and the AMST for

those calculations in which the AMST was included.

.§/ It has been assumed for purposes of these calculations that

75 percent of B-747 cargo capacity is oversize.

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o CRAF planes can carry no outsize cargo. Narrow-body

GRAF planes (B-707 equivalents) can carry bulk cargo

only. Wide-body CRAF planes (B-747 equivalents) can

carry bulk and oversize cargo. Since the unit of measure

is a composite of several different planes, this analysis

assumes that 75 percent of the allowable payload is

oversize and the remaining 25 percent is bulk cargo. _9_/

o The density of bulk and oversize cargo is assumed to be

equal.

o Airlift capacity is not reduced by attrition.

o Airlift operations are perfectly efficient in that this

analysis assumes no limitations on fuel availability,

no loading and unloading constraints, and no limits

on intermediate refueling or overflight rights.

The tables presented in the text of the paper are expressed

in terms of delivery rates, which are defined to be that distance

that a force can be transported for each unit of time. Delivery

rates are expressed by the following formula:

(3) C

Where

C. = Delivery rate for force j

D. = Distance traveled in deployment

T. = Time in days to move force J_ (closure time)

^ [derived from equation (2)]

9/ When the mix of various airlift resources is changed, there

are times when bulk cargo exceeds the capacity of B-707s (and

the 25 percent of B-747 capacity that is limited to bulk

cargo). In those instances, the bulk cargo in excess of

exclusive bulk lift capacity is transported along with oversize cargo.

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QUALIFYING OBSERVATIONS

By using these formulas and planning variables, it is

possible to determine generally the time required to transport

a specified type of force to a certain location. It would be a

mistake, however, to assert t"- -t this is the actual performance

that can be expected by the airlift system in a real-life situation. Several qualifications should be specifically noted.

Transit Time Only. The calculations presented in the paper

consist of transit time only. In actual operations, additional

time would be required to ready units for loading in the United

States and to reassemble in the destination area and move to

the front lines. Some units take a good deal longer to prepare

for loading than others. For example, the 101st Airmobile Division relies extensively on helicopters, which require several days

of preparation time.

Support Units. Unclassified cargo data are limited to

figures provided by the Air Force in 1977. Since 1977, there has

been a change in the way support equipment is divided for planning

purposes. The figures used in Table A-3 for Army support cargo

reflect previous force planning, which utilized the concept of the

"initial support increment" (ISI). The ISI consisted of hypothetical inventories of equipment, supplies, and units needed to

support the unit in its initial deployment. Long-term support was

dependent upon yet another echelon, known as the "sustaining

support increment."

These two planning devices have been replaced by new planning

categories, known as "non-division combat support" and "tactical

support increments." These latter components are not just new

labels for the previous support increments. Rather, the new

support packages have somewhat different mission requirements.

The relative ranking of types of units by weight and cargo distribution is similar to previous support packages.

Resupply. These calculations do not include cargo that

consists of supplies needed to replenish and sustain combat

units. Such resupply cargo calculations depend on assumptions

about the intensity of combat and on consumption rates associated with different combat environments. These figures are not

available in a public source. It can generally be said, however,

that resupply cargo will delay deployments, particularly for

deployments to non-NATO regions. Some war reserves are maintained

in Europe. This is not the case in non-NATO areas, where some

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airlift resources will have to be devoted to resupply cargo. In

addition, pre-positioning of equipment in Europe changes consumptions patterns in ways that might affect airlift. These

considerations, while important to note, cannot he treated specifically in this analysis.

Deployment Schedules. Actual deployments consist of literally hundreds of missions from dozens of ports of embarkation.

These calculations cannot represent the complexity of actual

deployment schedules. Therefore, when the discussion indicates

that a certain number of days is required to transport a given

unit, it more appropriately means that transit time equivalent to

that number of days of lift capacity must be devoted to the unit

in question. Actual elapsed time in a contingency might differ—

up or down—from this planning figure, depending on the specific

deployment plan used.

Artificial Force Packages. Calculations generally relate

to generic types of divisions and not, with the exception of

the airmobile and airborne divisions, to actual divisions.

Any deployment would also include tactical fighter squadrons,

reconnaissance and observation aircraft, tactical transports, air

defense units, and so on. Further, any airlift operation would

depend on air traffic control units, aerial port personnel, and so

forth, just to manage the transportation operation. In short,

airlift deployment of a fighting force is far more complex than

tonnage figures can portray.

81

O