CONGRESS OF THE UNITED STATES

CONGRESSIONAL BUDGET OFFICE

A

STUDY

AUGUST 2006

The Army’s Future 

Combat Systems 

Program and 

Alternatives

CBO
Pub. No. 2565
The Congress of the United States O Congressional Budget Office

CBO

The Army’s Future Combat Systems 

Program and Alternatives

August 2006

A

STUDY
Notes

Unless otherwise indicated, all years referred to in the study are federal fiscal years (which run 

from October 1 to September 30), and all costs are expressed in 2006 dollars.

Numbers in the text and tables may not add up to totals because of rounding.

Cover art from the Department of the Army.
Preface

The Army is attempting to transform itself from a force designed primarily to fight large 

and protracted wars in a limited number of locations to one capable of reacting rapidly to 

crises anywhere in the world. In its endeavor to make its combat units more versatile and 

agile, the Army is planning to replace its heavy, aging armored combat vehicles with newer, 

lighter systems that it expects will be as lethal and survivable as the vehicles they are replacing. 

Several types of manned vehicles as well as unmanned aerial and ground vehicles, missile 

launchers, and communications links would be developed and procured within a single program known as the Future Combat Systems (FCS) program.

This study by the Congressional Budget Office (CBO), which was prepared at the request of 

the Ranking Member of the Tactical Air and Land Forces Subcommittee of the House Committee on Armed Services, considers the near- and long-term implications of the FCS program. It also examines several alternatives for modernizing the Army’s armored forces and 

estimates the costs and savings associated with those options as well as their effects on the 

Army’s fleet of armored vehicles and the ability of its armored units to deploy overseas. In 

keeping with CBO’s mandate to provide objective, impartial analysis, the report makes no 

recommendations.

Frances M. Lussier of CBO’s National Security Division prepared the study under the general 

supervision of J. Michael Gilmore. The author would like to thank Michael J. Bennett of 

CBO for his assistance in fact-checking the document as well as former Department of 

Defense official Thomas P. Christie for his comments and Army personnel for their help. (The 

assistance of external participants implies no responsibility for the final product, which rests 

solely with the author and CBO.) Victoria Liu, also of CBO, reviewed the manuscript, and 

Arlene Holen, Sarah Jennings, Jo Ann Vines, Jason Wheelock, and Christopher Williams provided comments on earlier drafts of the study.

Leah Mazade edited the report, and Christine Bogusz proofread it. Cindy Cleveland produced 

drafts of the text and tables, and Maureen Costantino designed the cover and prepared the 

study for publication. Lenny Skutnik produced the initial printed copies. This publication 

and others may be found at www.cbo.gov.

Donald B. Marron

Acting Director

August 2006

Contents

Summary xi

1 The Army’s Heavy Forces and Armored Vehicles 1

Overview of the Army’s Armored Vehicle Fleet at the End of 2003 2

Issues Regarding Today’s Armored Forces and Vehicles 5

2 Description of the Army’s Modularity Initiative and Future 

Combat Systems Program 17

The Modularity Initiative 17

The Future Combat Systems Program 21

3 Potential Effects of and Concerns About the Army’s 

Modernization Plans 29

How Modernization Plans Would Affect the Army’s Budget 29

How Modernization Plans Would Affect the Army’s Ability to

Deploy Units Quickly 31

How the Administration’s Plan Would Affect the Army’s Armored 

Combat Vehicle Fleet 32

Concerns Regarding the Army’s FCS Program 34

4 Alternative Approaches to Modernizing the Army’s

Heavy Forces 47

Alternative 1. Develop and Procure FCS Components That 

Will Collect and Disseminate Information 47

Alternative 2. Develop and Procure FCS Components That 

Will Enhance the Army’s Long-Range Strike Capability 54

Alternative 3. Emphasize Investment in New Manned

Combat Vehicles 57

Alternative 4. Develop a Scaled-Down FCS Network and 

Integrate It with Existing Systems 60
VI THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

A A Description and History of the Army’s Current Armored Vehicles 63

B CBO’s Methods for Estimating Airlift Requirements 71

C Definitions of Technology Readiness Levels and Assessments of 

Critical Technologies for the Army’s Future Combat 

Systems Program 73

D Methods Used to Estimate Costs 81
CONTENTS VII

Tables

S-1. FCS Components and Current Counterparts in Combat Brigades xiii

S-2. Comparing the Army’s Modular Heavy Combat Brigades and Brigades

Equipped with Future Combat Systems xviii

S-3. Time Needed to Deploy Equipment of Combat Units to East Africa xix

S-4. Emphasis of and FCS Components Included in Alternatives xxi

S-5. Total Acquisition Costs from 2007 to 2025 for the Administration’s

Plan and Alternatives xxii

1-1. Characteristics of Models of the M1 Abrams Tank in 2003 3

1-2. Characteristics of Models of the M2/M3 Bradley Fighting Vehicle in 2003 6

1-3. Characteristics of Models of M113-Based Vehicles in 2003 7

1-4. Characteristics of Models of the M109 Self-Propelled Howitzer in 2003 9

1-5. Army Units Equipped with Armored Vehicles in 2003 10

1-6. Armored Vehicles Needed to Equip and Support the Army’s Heavy Units in 2003 12

1-7. Comparing the Army’s Light Infantry, Airborne, and Armored Units in 2003 13

2-1. Comparing the Army’s Premodular and Modular Combat Force Structures 18

2-2. Comparing the Army’s Premodular Heavy Brigade Combat Teams and 

Modular Heavy Combat Brigades 19

2-3. Armored Combat Vehicles Needed to Equip and Support the Army’s 

Modular Heavy Combat Brigades in 2011 20

2-4. FCS Replacements for Armored Vehicles in the Army’s Modular Heavy

Combat Brigades 23

3-1. Planned New Components for an FCS-Equipped Brigade 30

3-2. Total Costs for the Army’s Modularity Initiative 32

3-3. Selected Items That the Army Plans to Buy to Implement Its Modularity 

Initiative 33

3-4. Upgrades Included in the Administration’s Plan for 2007 to 2016 34

3-5. Comparing the Army’s Premodular Heavy Brigade Combat Teams, Modular 

Heavy Combat Brigades, and Brigades Equipped with Future Combat Systems 35

3-6. Time Needed to Deploy Equipment of Combat Units to East Africa 36

4-1. Alternatives to the Administration’s Current Plan for the FCS Program 48
VIII THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

4-2. Procurement of FCS Components Under the Administration’s Plan and

Under Alternative 1 49

4-3. Total Acquisition Costs from 2007 to 2025 for the Administration’s Plan and 

Alternatives 51

4-4. Time Needed to Deploy Equipment of Combat Units to East Africa 53

4-5. Procurement of FCS Components Under the Administration’s Plan and

Under Alternative 2 55

4-6. Procurement of FCS Components Under the Administration’s Plan and

Under Alternative 3 58

A-1. Characteristics of Models of the Abrams (M1) Tank 67

A-2. Characteristics of Models of the Bradley Infantry (M2) and Cavalry (M3)

Fighting Vehicles 68

A-3. Characteristics of Models of the M113-Based Family of Vehicles 69

A-4. Characteristics of Models of the M109 Self-Propelled Howitzer 70

B-1. CBO’s Estimates of Maximum Airfield Capacity 72

C-1. Definitions and Descriptions of Technology Readiness Levels 74

C-2. Technology Readiness Levels of Critical Technologies for the FCS Program in

May 2003 77

C-3. Status of Critical Technologies for the FCS Program As Assessed After May 2003 78

D-1. Rates of Historical Cost Growth for Military Systems 83

Figures

S-1. Annual Costs of the Administration’s Plan for the Future Combat Systems 

Program and Alternatives xiv

S-2. Effect of the Administration’s Plan for the FCS Program and Alternatives 

on the Average Age of the Army’s Active Armored Combat Vehicle Fleet xvii

1-1. The Army’s Armored Combat Vehicle Fleet, 1980 to 2003 2

1-2. Abrams Tank 4

1-3. Bradley Fighting Vehicle 5

1-4. M113 Armored Personnel Carrier 5

1-5. M109 Self-Propelled Howitzer 8

Tables (Continued)
CONTENTS IX

1-6. Average Age of the Army’s Armored Combat Vehicles, 1990 to 2003 10

1-7. Time Needed to Deploy Equipment of Combat Units from the Continental 

United States to East Africa 14

1-8. Requirements and Inventories for the Army’s Armored Combat Vehicles in 2003 15

2-1. Manned FCS Vehicles 22

2-2. Unmanned FCS Aerial Vehicles 24

2-3. Unmanned FCS Ground Vehicles 25

2-4. Other Unmanned FCS Systems 26

2-5. Disposition of the Army’s Heavy Brigades Under the Administration’s Plan 27

3-1. Projected Total Annual Investment in the Future Combat Systems Program 31

3-2. Average Age and Composition of the Active Armored Combat Vehicle Fleet 37

3-3. Average Age and Composition of the Armored Combat Vehicle Fleet 

Under the Administration’s Plan 38

3-4. Average Age and Composition of the Active Armored Combat Vehicle Fleet 

Under the Administration’s Plan 38

3-5. Status of Critical Technologies for FCS Components at the End of 2005 39

3-6. The Army’s Major Procurement Programs and Budget Through 2025 40

3-7. Estimated Total Annual Costs for the Future Combat Systems Program 

Including Potential Cost Growth 43

3-8. Average Age of the Active Armored Combat Vehicle Fleet Under the 

Administration’s Plan with Additional Upgrades 44

3-9. Average Age and Composition of the Active Armored Combat Vehicle 

Fleet with Limited Purchases of FCS Components 45

4-1. Annual Costs of the Administration’s Plan for the Future Combat Systems 

Program and Alternatives 52

4-2. Average Age and Composition of the Active Armored Combat Vehicle Fleet 

Under All Alternatives 54

A-1. Average Age and Composition of the Army’s A1 Abrams Tank Fleet 63

A-2. Average Age and Composition of the Army’s M2/M3 Bradley Fighting 

Vehicle Fleet 64

Figures (Continued)
X THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

A-3. Average Age and Composition of the Army’s M113-Based Vehicle Fleet 65

A-4. Average Age and Composition of the Army’s Fleet of M109 Self-Propelled 

Howitzers 66

Figures (Continued)
Summary

Roughly half of the Army’s combat forces at the 

end of 2005 were so-called heavy units—forces that are 

equipped with armored vehicles and that provide significant firepower. To support those units, the Army maintains a fleet of approximately 28,000 armored vehicles. 

Now that the Cold War is over, some defense experts have 

questioned the relevance of such vehicles to the current 

national security strategy and their continued usefulness 

(notwithstanding their contributions to recent operations, such as Desert Storm and Iraqi Freedom). The average age of the armored combat vehicle fleet at the end 

of 2005 was relatively high, and the fleet comprises vehicles designed several decades ago. Moreover, units 

equipped with the vehicles in the current fleet are too 

large and too heavy to be moved overseas easily and 

quickly by the Air Force’s C-17s, the most numerous of 

its long-range transport planes. For all practical purposes, 

heavy units must be transported overseas by ship—a process that takes weeks.

In today’s environment of rapidly evolving conflicts, the 

Army’s goal is to have units that have the combat power 

of heavy units but that can be transported anywhere in 

the world in a matter of days. To address concerns about 

the armored vehicle fleet’s aging and the difficulties involved in transporting it—as well as to equip the Army 

more suitably to conduct operations overseas on short notice using forces based in the United States—the service 

created the Future Combat Systems (FCS) program in 

2000. A major modernization effort, the program is designed in part to develop and purchase vehicles to replace 

those now in the heavy forces; the new vehicles would be 

much lighter, thereby easing the deployment of units 

equipped with them. But the FCS program, poised to develop a total of 18 new systems (including eight manned 

vehicles to replace those in the Army’s current armored 

fleet) and a network to connect them all will not field any 

new vehicles until December 2014 at the earliest. Furthermore, because those new vehicles will be expensive, 

the Army plans to buy relatively small quantities of them 

each year. As a result, the armored vehicles now in the 

Army’s combat units will not all be replaced by FCS components until after 2035, a prospect that has evoked concerns about the costs of maintaining those older vehicles 

and upgrading them to prevent their becoming obsolete.

In addition, questions have been raised about the FCS 

program’s technical feasibility and affordability. Some experts doubt that the Army can develop and test the necessary technologies in time to start producing lightweight 

manned vehicles by 2012—a requisite for meeting the 

deadline to field them according to the Army’s current 

schedule. Another concern is funding for the quantities 

of FCS equipment that the Army is now planning to buy. 

Any reduction in the FCS procurement rate would force 

the Army to retain its already aging armored vehicles even 

longer and to invest more funds in their maintenance.

In the analysis presented in this report, the Congressional 

Budget Office (CBO) examined the current status of the 

Army’s fleet of armored vehicles and assessed the speed of 

deployment of the service’s heavy forces. It also evaluated 

the FCS program, considering the program’s costs as well 

as its advantages and disadvantages and comparing it with 

several alternative plans for modernizing the Army’s 

heavy forces.1 CBO’s analysis supports the following observations:

B The FCS program must surmount substantial technical and funding challenges if it is to develop and initially field all of the individual FCS components as 

currently scheduled—that is, by December 2014.

1. A fuller discussion of the four alternatives that CBO evaluated, 

each of which emphasized different aspects of the FCS program—

information collection and sharing (Alternative 1); long-range 

strike missions (Alternative 2); new vehicular technology (Alternative 3); and integrating the FCS network into existing systems 

(Alternative 4)—can be found later in this summary.
XII THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

B According to the Army’s estimates, total annual costs 

to purchase the various FCS components could approach $10 billion. However, if such costs grew as 

those of similar programs have in the past, annual 

costs could reach $16 billion.

B Moreover, if the Army fielded FCS vehicles according 

to its current schedule, $1 billion or more of additional funding might be needed annually from 2010 

through 2016—and smaller amounts thereafter—to 

maintain and upgrade the Army’s inventory of aging 

ground combat vehicles.

B Although one of the main purposes of the FCS program is to speed the movement of Army combat units 

overseas, replacing the current fleet of armored vehicles with FCS components will not significantly reduce deployment times. 

B Alternatives to the currently planned FCS program 

that would eliminate all or part of the program’s 

ground vehicles while retaining its communications 

equipment and, in some cases, its sensors would reduce the program’s average annual costs to about 

$5 billion to $7 billion. Under such alternatives, the 

Army would incorporate some FCS technologies into 

its current fleet of armored combat vehicles and upgrade those vehicles at the same time, thereby increasing their capabilities and extending their useful lives. 

However, if it did so, the Army would forgo potential 

benefits of the capabilities it now seeks in the FCS 

program.

Description of the Army’s Future

Combat Systems Program

The FCS program was first conceived by then Army 

Chief of Staff General Eric Shinseki to enable the Army 

to react to overseas crises more quickly and with overwhelming combat power. The service initiated the program to develop a new generation of combat vehicles that 

would be as lethal and survivable as the heavy weapons it 

now fields but that would weigh much less, be more easily transported, and require far less logistical support.

According to the Army, the FCS program would greatly 

enhance the capabilities and agility of its heavy units by 

developing new systems to replace most of the combat vehicles that currently equip the service’s heavy units and by 

developing and buying several types of unmanned aerial 

and ground vehicles to provide remote—and sometimes 

autonomous—surveillance and protection. Specifically, 

the Army would develop eight new types of armored vehicles, four classes of unmanned aerial vehicles (UAVs), 

three types of unmanned ground vehicles, unattended 

ground sensors, a missile launcher, and intelligent munitions, all of which would be linked by an advanced communications network into an integrated combat system.

Manned FCS Vehicles

The eight new manned vehicles that would be developed 

through the FCS program are intended to replace the armored vehicles currently assigned to the Army’s heavy 

combat units (see Summary Table 1). The eight variants 

would share a common chassis and engine as well as other 

components, which would reduce the logistics burden associated with maintaining them. The vehicles would have 

new weapons, sensors, and types of protection, making 

them, according to the Army, more capable than current 

systems. The FCS vehicles are also being developed to be 

more fuel efficient; some armored vehicles in the Army’s 

current fleet—notably the Abrams tanks and Bradley 

fighting vehicles—go less than two miles on a gallon of 

fuel.

Initially, the Army aimed to develop FCS vehicles that 

weighed less than 20 tons and that could be transported 

by the Air Force’s C-130 aircraft. However, the weight 

limit for the initial design of the manned FCS ground vehicles has been relaxed and is now set at 24 tons—which 

would nevertheless be about one-third of the weight of 

the latest model of the Abrams tank and roughly threequarters that of the Bradley fighting vehicle. 

Unmanned Aerial and Ground Vehicles

Four classes of unmanned aerial vehicles and three types 

of unmanned ground vehicles would be developed under 

the FCS program to provide, along with the manned systems, surveillance, protection, and cargo-carrying capacity. The aerial vehicles would have varying capabilities: 

for example, the smallest, Class I, UAV would weigh less 

than 15 pounds, have a range of eight kilometers (km), 

and be able to stay aloft for about one hour, whereas the 

largest, Class IV, UAV could weigh more than 3,000 

pounds, have a range of 75 km, and be able to stay aloft 

for up to 24 hours. The three types of unmanned FCS 

ground vehicles, or robots, are intended in general to 

lighten the load of individual soldiers by providing continuous surveillance, carrying supplies, or investigating 
SUMMARY XIII

Summary Table 1.

FCS Components and Current Counterparts in Combat Brigades

Source: Congressional Budget Office based on data from the Department of the Army; Army Project Manager, Unit of Action, “Future Combat Systems (FCS); 18+1+1 Systems Overview” (September 2005); and Army Training and Doctrine Command (Tradoc), Unit of 

Action Maneuver Battle Lab and Tradoc System Manager FCS, “Family of Systems Battle Book” (January 31, 2005).

Note: FCS = Future Combat Systems; UAV = unmanned aerial vehicle; km = kilometer; REMBASS = remotely monitored 

battlefield sensor system.

high-risk areas or locations (for example, tunnels or 

caves).

Unattended Sensors, Intelligent Munitions,

Launchers, and the Network

The remaining hardware systems to be developed under 

the FCS program include ground sensors, a missile 

launcher, an intelligent munitions system, and equipment associated with the communications and datasharing network. The unattended ground sensors are 

small modules equipped with several different types of 

sensors that are intended to act as remote sentries and 

provide early warning of an attack. The intelligent munitions system is based on sophisticated land mines that can 

self-destruct on command or at a specific time. The 

ground sensors and the munitions system are designed to 

be relatively inexpensive and to detect and destroy intruders over a wide area. The non-line-of-sight launch system—a box-shaped launcher equipped with 15 advanced 

missiles—may be operated remotely or set to operate autonomously; it is intended to carry out rapid-fire attacks 

on targets at a distance of as much as 70 km. 

Existing System Being Replaced

Destroy the enemy

Transport and protect soldiers

M113 armored personnel carrier

Scout

Provide fire support

Recover stranded vehicles

Provide fire support

Carry cargo; detect and counter mines None

Equipment

Provide surveillance up to a distance of 8 km

Provide surveillance up to a distance of 16 km

Provide surveillance and communications Shadow 

relay up to a distance of 40 km

Provide surveillance and communications 

relay up to a distance of 75 km

of 70 km

REMBASS

"Smart" land mines

Class IV 

Non-Line-of-Sight Launch System

Unattended Ground Sensors

Intelligent Munitions System

Small Unmanned Ground 

Class I 

Class II 

Class III 

Non-Line-of-Sight Cannon

Recovery and Maintenance

Command and Control

Non-Line-of-Sight Mortar

Component 

Mounted Combat 

Infantry Carrier

Reconnaissance and Surveillance

Mission

Unmanned Aerial Vehicles

None

None

Other

Raven 

None

Carry out precision attacks up to a distance

Transport and protect commanders

Treat and evacuate the wounded

Perform sentry duty; provide cover

Unmanned Ground Vehicles

M113-based vehicle

Investigate small, confined spaces

None

None

None

Medical 

Armed Robotic 

Multifunction Utility, Logistics, and 

Detect and identify intruders

Channel enemy movement

Manned Vehicles

Abrams tank

Bradley infantry fighting vehicle and 

Bradley cavalry fighting vehicle

M109 howitzer

M88 recovery vehicle

M113-based vehicle
XIV THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Summary Figure 1.

Annual Costs of the Administration’s Plan for the Future Combat Systems 

Program and Alternatives

(Billions of 2006 dollars)

Source: Congressional Budget Office.

Note: See Summary Table 4 for details of the alternatives.

a. Based on documents submitted with the President’s 2007 budget, which includes $6 billion for upgrades to existing systems.

b. Includes upgrades to Abrams tanks, Bradley fighting vehicles, M113-based vehicles, and M109 howitzers to maintain a relatively constant 

average age for each fleet of vehicles after 2011.

The final component of the FCS program is the network, 

which comprises the common operating software that 

would allow all of the FCS elements to communicate 

with one another and with other Army systems and to 

share data. The network also includes the communications and computer systems that are planned to provide 

secure, reliable access to information collected by the 

many surveillance sensors in the future FCS-equipped 

brigade.

Schedule for Fielding FCS Components 

Despite the complexity and diversity that the 18 individual FCS components represent, the Army plans to field 

them all on a very tight schedule. Components would be 

introduced in stages (which the Army refers to as spinouts, or spirals); fielding would begin in 2010 with the 

unattended ground sensors, the non-line-of-sight launch 

system, and the intelligent munitions system. However, 

the Army does not expect to field the first combat brigade 

to be equipped with all 18 systems until December 2014. 

After that, the service plans to equip its combat brigades 

with FCS components at a maximum rate of 1.5 brigades 

per year, purchasing 15 brigades’ worth of equipment as 

part of the first installment—or “increment”—of procurement for the program.2 Under the current schedule, 

equipment for the 15th brigade would be purchased in 

2023, allowing fielding of those systems in 2026.

2005 2010 2015 2020 2025

0

2

4

6

8

10

12

14

Administration's Plan with

Additional Upgrades

Administration's Plan

Alternative 1 Alternative 2

Alternative 3

Alternative 4

a

b

2. Procurement of FCS components is often discussed in terms 

of a brigade’s worth of equipment, which includes more than 

300 manned vehicles, approximately 230 unmanned ground vehicles, more than 200 UAVs, and numerous additional unattended 

ground sensors, launch systems, and associated munitions. 
SUMMARY XV

Costs of the Army’s FCS Program

The FCS program represents by far the biggest single investment that the Army is planning to make during the 

next 20 years. The research and development (R&D) 

portion of the program is scheduled to extend through 

2016 and cost a total of $21 billion from 2007 to 2016. 

The Army estimates that total procurement costs for the 

first 15 brigades’ worth of systems will be about $100 billion, or an average unit procurement cost per brigade of 

$6.7 billion.3

 The Army plans to start its annual purchases of 1.5 brigades’ worth of equipment in 2015; as 

long as the program continues purchases at that rate, 

from that year on it will require annual funding of $8 billion to $10 billion (see Summary Figure 1).

Concerns About the FCS Program

The Government Accountability Office (GAO) and 

other defense experts have expressed a number of reservations about the Army’s ability to implement the FCS program in its current form. Among their concerns are the 

technological challenges facing developers of the various 

systems; the costs of the program, in light of the Army’s 

other funding needs; the condition of the service’s current 

fleet of armored vehicles, which will be retained for several decades until they can be replaced by FCS vehicles; 

the limited improvement in the speed of Army units’ deployment that the fielding of FCS components is likely to 

bring; and the survivability of FCS vehicles in hostile environments.

Technological Readiness of FCS Components

Defense analysts have questioned whether the planned 

FCS components will be ready to go into production in 

2012. GAO, for example, has criticized the Army’s proposed schedule for developing and fielding the 18 systems, given that, according to GAO, it would require developing multiple systems and a network in the same 

amount of time that the Department of Defense (DoD) 

typically takes to develop a single advanced system.4 Also 

according to GAO, none of the numerous technologies 

that are critical to developing the various FCS components—technologies that should have been “mature” before the program entered the system development and 

demonstration (SDD) phase in 2003—were judged to be 

so in an independent assessment dated April 2005.5

 Using GAO’s criteria, those technologies may not be mature 

until 2012, when the first FCS component is slated to go 

into production.

Another technological hurdle is development of the software that will allow all of the new systems to communicate and share data with one another and with the Army’s 

existing systems. At least 34 million lines of software code 

must be generated—about twice the amount needed for 

the Joint Strike Fighter, DoD’s largest software development effort to date. 

The severity of the technological challenges associated 

with developing all 18 FCS components and the network 

to link them has already led to increases in the time and 

funds allotted to FCS development. As the program was 

first described by General Shinseki in October 1999 and 

as the schedule stood in November 2002, FCS development would have included a relatively short (three-year) 

SDD phase starting in the spring of 2003, with all 18 systems slated to enter production by 2006 and to start initial fielding in 2008. Since then, the schedule has been 

extended by more than six years, and the first unit to be 

equipped with all 18 systems will not be fielded until December 2014 (fiscal year 2015) at the earliest.

Growth of the FCS Program’s Costs

As noted earlier, the Army estimates that the FCS program will require $8 billion to $10 billion annually starting in 2015, when it plans to begin buying 1.5 brigades’ 

worth of equipment per year. During the preceding five 

years, the program will have consumed increasingly larger 

shares of the Army’s procurement budget: if the Army’s 

3. CBO was unable to develop an independent estimate of the cost 

of a brigade’s worth of equipment because some of the individual 

FCS components are not yet fully defined.

4. Statement of Paul L. Francis, Director, Acquisition and Sourcing 

Management, Government Accountability Office, before the Subcommittee on AirLand of the Senate Committee on Armed Services, published as Government Accountability Office, Defense 

Acquisitions: Future Combat Systems—Challenges and Prospects for 

Success, GAO-05-442T (March 16, 2005).

5. A fully mature technology, according to GAO’s definition, is one 

that has been demonstrated in a prototype in an operational environment. In contrast, the Army considers a system that has been 

demonstrated in a prototype in a relevant environment to be sufficiently mature to be used in the SDD phase. The April 2005 independent assessment (Office of the Deputy Assistant Secretary of 

the Army for Research and Technology, Technology Readiness 

Assessment Update) was cited in Government Accountability 

Office, Defense Acquisitions: Improved Business Case Is Needed for 

Future Combat System’s Successful Outcome, GAO-06-367 (March 

2006).
XVI THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

procurement funding grew after 2011 at a rate equal to 

inflation—that is, if it remained at the same level in 2006 

dollars—the FCS program’s share of the service’s planned 

$21 billion procurement budget would rise from almost 

6 percent in 2011 to roughly 50 percent in 2015 and remain at or above 40 percent through 2025. (For comparison, the Army’s purchase of ground combat vehicles during the 1980s peaked at 20 percent of the Army’s total 

procurement budget.) Dedicating such a large proportion 

of the service’s procurement funding to the FCS program 

would leave little money for purchasing other weapon 

systems (such as helicopters) or needed support equipment (such as generators and ammunition).

Also giving rise to experts’ concerns is the fact that the 

FCS program has already experienced significant cost 

growth since it entered the SDD phase in spring 2003. At 

that time, the program’s total acquisition cost for 15 brigades’ worth of equipment—that is, including research, 

development, testing, evaluation, and procurement—was 

projected to be about $80 billion. The Army’s latest estimate of that cost has increased to almost $130 billion, or 

roughly 60 percent more than its original estimate.6 And 

if the history of the Army’s major weapons programs is 

any indication, the costs of the FCS program may continue to rise. Historical trends suggest that DoD’s major 

programs experience growth in R&D costs ranging from 

16 percent to slightly more than 70 percent and growth 

in procurement costs ranging from 11 percent to roughly 

70 percent—as measured from estimates prepared when 

the programs entered the SDD phase. (The higher end 

of the range reflects historical cost growth for ground 

vehicles.)

Overall, the different types of equipment that the FCS 

program plans to develop lead CBO to estimate that the 

Army’s acquisition costs may grow by about 60 percent. 

Given some defense experts’ view that the program’s entry 

into the SDD phase was premature, the FCS program 

may continue to experience cost growth at historical 

rates. If it does, the average annual funding needed for 

the program, CBO estimates, may climb from the $8 billion to $10 billion projected most recently by the Army 

to between $13 billion and $16 billion.

Age of the Army’s Armored Combat Vehicle Fleet

The total size of the FCS program—in terms of number 

of brigades’ worth of equipment purchased—and the rate 

at which the program is executed will determine how 

many of the armored vehicles in the Army’s current inventory must be retained and for how long. At the end of 

2005, the Army had an armored combat vehicle fleet of 

almost 28,000 vehicles, including 5,850 Abrams tanks, 

6,650 Bradley fighting vehicles, 13,700 vehicles based 

on the M113 personnel carrier, and 1,500 M109 selfpropelled howitzers. Those vehicles, and the armored 

combat fleet as a whole, are aging. M113-based vehicles, 

which constitute almost half of the fleet, were first introduced into Army units in the 1960s. Most of the rest of 

the service’s armored vehicles—namely, the Abrams tanks 

and Bradley fighting vehicles—are based on technology 

that is roughly 20 years newer. But at the end of 2005, 

even those vehicles, which have undergone several upgrades since they were first produced, had average ages of 

15 and 11 years, respectively. Many of the vehicles that 

provide much of the Army’s current combat power could 

thus reach the end of their useful service (based on a useful service life of 20 to 30 years) in the next decade—

unless DoD invests significant sums in upgrading or 

modifying them. 

The Army is currently reorganizing its fighting forces under what is known as its modularity initiative. That reorganization will reduce both the size of armored units 

and their total number; consequently, the service will 

need fewer armored vehicles and could retire more than 

13,000 of its oldest by 2011. Those retirements would 

yield an armored vehicle fleet with a lower average age in 

that year than would have been possible without the extensive retirements. Nevertheless, the resultant fleet, with 

an average age of 13 years, would still be relatively old.

Although the FCS program could ultimately replace most 

of the armored vehicles that currently equip the Army’s 

combat brigades, the average age of those vehicles before 

they were retired would significantly exceed the Army’s 

guidelines. Manned FCS vehicles would not begin to be 

introduced into units until December 2014 at the earliest. By the time the Army began to field significant numbers of them—roughly 500 per year starting in 2018—

the average age of the armored combat vehicle fleet would 

6. An independent estimate of the cost of the FCS program by the 

Cost Analysis Improvement Group (CAIG) in the Office of the 

Secretary of Defense was submitted to the Congress in June 2006 

and suggests that the FCS program’s costs may be higher than the 

Army’s latest projections indicate. According to the CAIG, total 

acquisition costs for the FCS program, including costs for R&D 

and procurement, could range from $160 billion to $173 billion 

(in 2006 dollars). 
SUMMARY XVII

Summary Figure 2.

Effect of the Administration’s Plan for the FCS Program and Alternatives on the 

Average Age of the Army’s Active Armored Combat Vehicle Fleet

(Average age in years)

Source: Congressional Budget Office.

Notes: See Summary Table 4 for details of the alternatives.

The “active fleet” comprises all models of the vehicles that CBO estimates will be needed to equip and support modular units in both 

the Army’s active component and the Army National Guard. (Modular units are those resulting from the Army’s ongoing modularity 

initiative, which seeks to make the service more flexible by changing its structure from one based on 18 divisions, several of unique 

design, to one based on 70 combat brigades, each one of only three designs.)

FCS = Future Combat Systems.

a. Based on documents submitted with the President’s 2007 budget, which includes $6 billion for upgrades to existing systems.

b. Includes upgrades to Abrams tanks, Bradley fighting vehicles, M113-based vehicles, and M109 howitzers to maintain a relatively constant 

average age for each fleet of vehicles after 2011.

be 16 years (see Summary Figure 2). Because the proposed annual purchases of armored vehicles under the 

FCS program represent only 3 percent of the total fleet, 

they will not begin to lower the fleet’s average age until 

2024—and even then, the average age could exceed 15 

years (the high end of what the Army considers the desirable range) for the foreseeable future. If the Army continued to purchase manned FCS vehicles after the first 15 

brigades’ worth had been bought, armored vehicles in the 

combat brigades and prepositioned sets (brigade-sized 

sets of equipment that DoD has positioned and maintains in several locations around the world) would have 

been totally replaced by FCS vehicles by 2037.7

 Until 

then, however, the Army’s current fleet of armored vehicles would need to be maintained in fighting condition.

The Army aims to keep the average age of its armored vehicles at or below half of their useful life by, first, continually upgrading them to reflect the capabilities of the latest models and, second, incorporating FCS technologies 

into them as the new systems become available. To that 

end, documents submitted with the President’s 2007 

2005 2010 2015 2020 2025 2030 2035 2040

0

6

8

10

12

14

16

18

20

Administration's Plan with

Additional Upgrades

Administration's Plan

Alternatives 1, 2, and 4

Alternative 3

a

b

7. Some M113-based vehicles and self-propelled howitzers that 

equip units other than combat brigades could be retained indefinitely.
XVIII THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Summary Table 2.

Comparing the Army’s Modular Heavy Combat Brigades and Brigades

Equipped with Future Combat Systems

Source: Congressional Budget Office based on data from the Department of the Army; Military Traffic Management Command Transportation Engineering Agency, Deployment Planning Guide: Transportation Assets Required for Deployment, MTMCTEA Pamphlet 700-5 

(May 2001); and Department of the Air Force, Air Mobility Planning Factors, Pamphlet 10-1403 (December 18, 2003).

a. “Modular” refers to the Army’s ongoing modularity initiative, which seeks to make the service more flexible by changing its structure 

from one based on 18 divisions, several of unique design, to one based on 70 combat brigades, each one of only three designs. “Heavy” 

units are those equipped with tracked armored vehicles.

b. Numbers are rounded to the nearest 10 vehicles.

c. Includes all tracked armored vehicles.

d. “Other vehicles” include wheeled vehicles that cannot drive for long distances on roads and the 20 helicopters and 150 unmanned ground 

vehicles in the FCS-equipped brigade.

e. Based on an average load of 60 tons for modular heavy brigades and 50 tons to 55 tons for FCS-equipped brigades and rounded to the 

nearest 10 sorties.

f. Either fast sealift ships or large medium-speed roll-on/roll-off ships will be needed but not both. Numbers of ships are rounded up to the 

nearest whole ship.

budget included roughly $6 billion from 2007 through 

2016 for upgrades to Abrams tanks, Bradley fighting vehicles, and M113-based vehicles. To continue those upgrades, pay for modernization of the Army’s M109 howitzers, and keep the average age of the vehicles required to 

equip its heavy units relatively constant after 2011, the 

Army must invest an additional $17 billion by 2025, in 

CBO’s estimation.8 That investment could bring the average age of the Army’s fleet of combat vehicles down 

from one that without upgrades would exceed 16 years 

in 2020 to one that would remain consistently below 

13 years (see Summary Figure 2).

Deployment of Army Units

Although a major goal of the FCS program is to make 

units equipped with armored vehicles easier to deploy 

overseas, replacing the Army’s existing armored vehicles 

with FCS components will not significantly reduce deployment time. An FCS-equipped force would yield at 

most a 19 percent reduction in the time needed to deploy 

Personnel (Number) 3,800 3,300

Vehicles (Number)b

Trackedc 370 320

1,310 910 ______ ______

1,680 1,230

Weight, All Equipment (Tons) 25,000 18,700

Coverage, All Equipment (Thousands of square feet) 320 260 to 290

420 340 to 370

3 2

2 1

Modular Heavy 

Combat Brigadea FCS-Equipped Brigade

Large medium-speed roll-on/roll-off

Trucks, trailers, and otherd

Total vehicles

Deployment of Equipment

By air (Number of C-17 sorties)e

By sea (Number of ships)f

Fast sealift

8. In developing that estimate, CBO assumed that in addition to 

incorporating systems that provided new capabilities, including 

some of those associated with the FCS network, an upgrade to an 

existing vehicle would also replace all components (such as 

engines and transmissions) needed to reset the vehicle’s effective 

age to zero.
SUMMARY XIX

Summary Table 3.

Time Needed to Deploy Equipment of 

Combat Units to East Africa

(Days)

Source: Congressional Budget Office based on data from the 

Department of the Army; Military Traffic Management 

Command Transportation Engineering Agency, Deployment Planning Guide: Transportation Assets Required for 

Deployment, MTMCTEA Pamphlet 700-5 (May 2001); and 

Department of the Air Force, Air Mobility Planning Factors, Pamphlet 10-1403 (December 18, 2003).

Notes: Units would be moved from the continental United States. 

The data do not reflect the time needed to move sustaining 

units or supplies. See the text for more discussion of 

alternatives.

a. The number of daily sorties constrained by the capacity of the 

airfield in East Africa, based on average airlift payloads per brigade of 60 tons for modular heavy units and 50 tons to 55 tons 

for units equipped with Future Combat Systems.

b. Based on documents submitted with the President’s 2007 

budget.

c. “Modular” refers to the Army’s ongoing modularity initiative, 

which seeks to make the service more flexible by changing its 

structure from one based on 18 divisions, several of unique 

design, to one based on 70 combat brigades, each one of only 

three designs. “Heavy” units are those equipped with tracked 

armored vehicles.

d. Besides combat brigades, divisions include headquarters and 

other support units.

heavy brigades by air. Whether equipped with current or 

FCS components, the Army’s heavy units comprise hundreds of tracked (mostly armored) vehicles and hundreds 

more trucks and trailers that require multiple aircraft sorties to deploy by air (see Summary Table 2). Yet the lack 

of extensive paved surfaces for receiving and unloading 

aircraft at most airfields in the world (excluding large 

U.S. military facilities such as those in Germany) limits 

the number of daily sorties those airfields can support. 

CBO estimates that given those constraints, transporting 

a brigade equipped with the Army’s existing armored

vehicles to the east coast of Africa by air may take 23 

days; moving an entire division similarly equipped may 

take 135 days, or more than four months (see Summary 

Table 3).9

 Brigades and divisions that are equipped with 

FCS components would take 18 to 20 days and 115 to 

130 days, respectively.

In contrast, seagoing ships can easily transport very large 

amounts of the Army’s existing equipment. Indeed, two 

or three of the Military Sealift Command’s (MSC’s) large 

seagoing ships can transport an entire brigade’s worth of 

equipment, and eight of those vessels can transport an entire division overseas. Most coastal regions of the world 

have at least one large port capable of receiving the MSC’s 

ships. And even though some of the equipment associated with a division equipped with either current armored vehicles or FCS components might have to be 

loaded onto some of the command’s slower ships, it 

would still take far less time to deliver a full heavy division by sea—27 days—than by air.

Survivability

Finally, several observers have questioned the basic assumption that underlies the survivability of the lightweight FCS components—which is that those lightly armored vehicles will be able to survive on the battlefield 

because they will have extensive knowledge of the enemy’s 

whereabouts, allowing them to avoid unexpected or disadvantageous encounters with enemy forces. If, however, 

the FCS sensors and communications network do not 

work as planned, the ability to avoid such encounters—

and thus the armored vehicles’ survivability—are uncertain. Moreover, other people, including soldiers returning 

from duty in Iraq, have argued that the most sophisticated sensors will not be able to detect and predict the 

kinds of dangerous situations that are now prevalent 

there.

23 25

18-20 25

23 25

24 25

3. New vehicular technology 24 25

23 25

135 27

115-130 27

140 27

140 27

3. New vehicular technology 145 27

135 27

Division-Sized Unitsd

Airlifta Sealift

Brigade-Sized Units

Administration's Planb

Modular heavy brigade with 

existing armored vehiclesc 

FCS-equipped brigade

Alternatives 

1. Information collection and

sharing

2. Long-range strikes

4. Existing-system upgrades

Administration's Planb

Four modular heavy brigades with 

existing armored vehiclesc 

Four FCS-equipped brigades

4. Existing-system upgrades

Alternatives 

1. Information collection and

sharing

2. Long-range strikes

9. CBO used as an example the transporting of Army units from the 

United States to Djibouti, on the east coast of Africa, to illustrate 

the trade-offs involved in moving units overseas.
XX THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Alternative Approaches to

Modernizing the Army’s Heavy Forces

CBO has analyzed four different options for modernizing 

the Army’s armored units that would address major concerns about the FCS program—specifically, its technical 

feasibility, its cost, and the slow rate of introduction of its 

systems into the Army’s force structure. Under the first 

three of those alternatives, the Army would retain different components of the FCS program (to emphasize systems that would contribute to different objectives of 

modernization) while canceling the remainder.

B Under Alternative 1, the Army would develop and 

purchase the full suite of sensors called for in the FCS 

program (to provide enhanced information-collection 

capabilities) and a version of the FCS network (to disseminate that information). With greater knowledge 

about the location and character of potential threats 

and the whereabouts of allies, Army forces, some argue, would be better able to respond and act appropriately, either individually or in concert. 

B Under Alternative 2, in addition to developing and 

purchasing a scaled-down version of the FCS network, 

the Army would emphasize those of the program’s systems that would enhance its ability to attack targets at 

ranges of greater than 20 km (that is, long-range strike 

missions).

B Under Alternative 3, the service would focus, first, on 

enhancing the maneuvering ability of the Army’s combat brigades by developing several of the new manned 

ground vehicles (particularly those that would replace 

the older M113-based vehicles and M109 howitzers 

currently in the fleet) and, second, on developing and 

purchasing a modified version of the FCS network to 

tie them together.

B Under Alternative 4, the Army would greatly reduce 

the scope of the FCS program, developing only a 

scaled-down network and integrating it with existing 

systems.

Under none of the alternatives would the service develop 

or procure the unmanned ground vehicles or intelligent 

munitions systems that are currently planned for the FCS 

program; however, under all of them, it would upgrade 

existing armored vehicles to convert them to the latest 

model of the current system and prevent their average age 

from increasing. Such upgrades would also integrate the 

capabilities associated with the retained portions of the 

FCS program when those new systems became available 

(see Summary Table 4).

Alternative 1. Develop and Procure FCS 

Components That Will Collect and Disseminate 

Information

To collect as much information as possible, the Army under this alternative would develop and procure the unattended ground sensors and all four classes of unmanned 

aerial vehicles included in the FCS program. It would 

also develop a less ambitious and less extensive version of 

the FCS network and install it in existing armored vehicles so that they could receive and exchange the information collected by the FCS sensors. All other FCS components, including the manned and unmanned ground 

vehicles, the non-line-of-sight launch system, and the intelligent munitions system, would be canceled.

CBO estimates that total costs under this alternative—

without taking historical cost growth into account—

would be $99 billion from 2007 through 2025, versus 

$140 billion for the full FCS program (without upgrades) 

for the same period. (However, costs for this alternative 

could reach $131 billion if they grew as they have in the 

past for similar defense programs; under the Administration’s plan for the FCS program through 2025, costs 

could grow to $231 billion.) Costs for the FCS components developed and purchased under this alternative 

would be $61 billion from 2007 through 2025, in CBO’s 

estimation; costs for upgrading the existing armored vehicle fleet would be $38 billion for the same period (see 

Summary Table 5). Annual costs to implement Alternative 1, which are just under $6 billion after 2015, would 

include about $2 billion to upgrade roughly 560 vehicles 

per year (see Summary Figure 1 on page xiv).

One of the advantages of this approach is that the Army 

could introduce new technology into its units more rapidly than under the Administration’s plan and at a lower 

cost. Because the service would be pursuing some of the 

least technologically risky of the FCS components, it 

could begin introducing them in 2010. And because 

those systems are also the least expensive of the 18 new 

components, the Army would purchase them at rates 
SUMMARY XXI

Summary Table 4.

Emphasis of and FCS Components Included in Alternatives

Source: Congressional Budget Office.

Note: UAV = unmanned aerial vehicle; FCS = Future Combat Systems.

a. Under Alternative 3, the Army would buy roughly 25 percent of the infantry carrier vehicles included in the Administration’s plan.

twice as high as the Administration’s planned 1.5 brigades’ worth per year—that is, it would purchase 33 brigades’ worth of the FCS sensors and UAVs as well as the 

network by 2025. And, CBO estimates, besides the lower 

total costs that this alternative would provide, relative to 

those under the Administration’s plan, cost growth would 

probably also be less—30 percent compared with roughly 

60 percent under the Administration’s plan. Although the 

Army under this alternative would incorporate some of 

the capabilities for sharing information to be provided by 

the FCS network, vehicle survivability would not depend 

as heavily on those capabilities as it would under the Administration’s plan.

The speed of deployment of the Army’s heavy units 

would be little affected under this alternative because the 

service would retain the armored vehicles now in those 

units. Indeed, if the alternative was implemented, the 

weight of a typical heavy brigade would increase slightly

—because additional trucks would be needed to support 

and transport the large number of UAVs that would be 

added to each brigade, increasing the time needed to airlift the brigade overseas by half a day. If transported by 

sea, however, the additional vehicles would not affect the 

time required to deploy a brigade- or division-sized 

unit—because the additional vehicles and supporting 

gear would fit easily on the ships used to move similar 

units with existing equipment (see Summary Table 3 on 

page xix).

Alternative Retained

Alternative 1 Collection and sharing Scaled-down network All manned vehicles

of information All classes of UAVs

Unattended ground sensors

Alternative 2 Long-range strikes Scaled-down network All manned vehicles

UAV Classes III and IV UAV Classes I and II

Unattended ground sensors

Non-line-of-sight launch system

Alternative 3 New vehicular technology Scaled-down network

Manned vehicles

Medical Mounted combat system

Infantry carriera Recovery and maintenance

Non-line-of-sight mortar Reconnaissance and surveillance

Non-line-of-sight cannon

Command and control

Alternative 4 Network integration with Scaled-down network

existing systems

Emphasis

FCS Components

Intelligent munitions system

All unmanned ground vehicles

Intelligent munitions system

All unmanned ground vehicles

Manned vehicles

All classes of UAVs

Canceled

All unmanned ground vehicles

Non-line-of-sight launch system

Non-line-of-sight launch system

Unattended ground sensors

Intelligent munitions system

All manned vehicles

Intelligent munitions system

All unmanned ground vehicles

All classes of UAVs

Unattended ground sensors

Non-line-of-sight launch system
XXII THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Summary Table 5.

Total Acquisition Costs from 2007 to 2025 for the Administration’s

Plan and Alternatives 

(Billions of 2006 dollars)

Source: Congressional Budget Office based on data from the Department of the Army.

Note: The estimated costs presented in this table do not take into account the possibility that costs may grow as they have in similar defense 

programs in the past. 

FCS = Future Combat Systems.

a. Includes costs to develop and purchase the first 15 brigades’ worth of FCS components—enough to equip slightly more than half of the 

Army’s planned 27 heavy brigades (19 brigades in the active Army and eight brigades in the Army National Guard).

b. Includes upgrades to Abrams tanks, Bradley fighting vehicles, M113-based vehicles, and M109 howitzers to maintain a relatively constant 

average age for each fleet of vehicles after 2011.

c. Includes unattended ground sensors, unmanned aerial vehicles (Classes I, II, III, and IV), and the network.

d. Includes unattended ground sensors, unmanned aerial vehicles (Classes III and IV), the non-line-of-sight launch system, and the network.

e. Includes manned vehicles (command and control, medical, non-line-of-sight mortar, non-line-of-sight cannon, and infantry carrier) and 

the network.

Costs Included in the President's Budget 

FCS Program's Increment 1a 21 101 122

06 6

Continued purchases of FCS components, 

0 18 18

Additional upgrades to existing vehiclesb 2 15 17 ___ ___ ___

Total 23 139 162

FCS Componentsc 15 46 61

Upgrades to Current Systemsb 2 36 38 __ __ __

Total 17 82 99

FCS Componentsd 15 52 67

Upgrades to Current Systemsb 2 36 38 ___ ___ ___

Total 17 89 106

FCS Componentse 16 52 67

Upgrades to Current Systemsb 2 33 35 ___ ___ ____

Total 18 85 103

FCS Network 14 16 30

Upgrades to Current Systemsb 2 36 38 ___ ___ ___

Total 16 52 68

Alternative 3. New Vehicular Technology

Alternative 4. Existing-System Upgrades

Further Costs as Estimated by CBO

2023 to 2025

Alternative 1. Collection and Sharing of Information

Alternative 2. Long-Range Strikes

Research and Development Procurement Total Acquisition

Administration's Plan

Upgrades to existing vehicles
SUMMARY XXIII

This alternative would suffer from several disadvantages 

when compared with the Administration’s plan for the 

FCS program. Under this approach, the Army would retain the armored combat vehicles in its current fleet indefinitely, and by 2040, some of those vehicles would 

have been in the Army’s inventory for almost 60 years. 

Another disadvantage is the technical risk involved in 

introducing network technology and associated communications links into old weapon systems, such as the 

Abrams tanks and Bradley fighting vehicles. Previous attempts to upgrade the communications and other electronic suites in those vehicles have met with difficulties. 

Alternative 2. Develop and Procure FCS 

Components That Will Enhance the Army’s

Long-Range Strike Capability 

Under the second alternative, the Army would retain 

those portions of the FCS program that enhanced its ability to carry out long-range strikes. Specifically, it would 

develop and procure the unattended ground sensors and 

longer-range UAVs (Classes III and IV) to detect and 

track targets. It would also develop and procure the nonline-of-sight launch system and its associated missiles to 

attack those targets. The combination of the UAVs and 

the missiles developed for the launch system would allow 

a brigade equipped with those weapons to identify and 

attack targets as far away as 70 km—long before most enemy weapons would be able to strike the corresponding 

U.S. targets. All of the ground vehicles in the FCS program, both manned and unmanned, would be canceled 

under this alternative, as would the shorter-range UAVs 

(Classes I and II) and the intelligent munitions system 

(see Summary Table 4 on page xxi). In addition, the 

Army would retain and upgrade the armored vehicles in 

its current inventory and develop and procure a scaleddown version of the FCS network (to tie the sensors and 

manned systems together).

Like the previous option, Alternative 2 would encompass 

the development and procurement of some of the least 

expensive of the proposed FCS components. As a result, 

annual procurement rates could be higher than under the 

Administration’s plan, and annual savings—relative to 

that plan—could still be achieved. Specifically, the Army 

under this alternative would buy three brigades’ worth of 

sensors, missile launchers, and network hardware annually starting in 2016 and continuing through 2025. Total 

costs for those systems, CBO estimates, would be $67 

billion from 2007 through 2025 (see Summary Table 5). 

Costs for upgrading the armored vehicles in the Army’s 

current fleet would be identical to those under the previous alternative—$38 billion—over that same period.

All told, costs under this alternative would total $106 billion from 2007 through 2025—$7 billion more than the 

costs under Alternative 1 but considerably less than those 

under the Administration’s plan. Annual costs under this 

alternative would be roughly $6 billion to $7 billion (see 

Summary Figure 1 on page xiv).

Compared with the Administration’s plan, this alternative 

would increase the firepower of Army brigades sooner 

and at a lower cost. Because parts of the FCS program—

primarily the high-risk ground vehicles—would be canceled, costs under this alternative would be $40 billion 

less from 2007 through 2025 compared with costs for the 

Administration’s plan when it includes the full FCS program (but no upgrades), extended through 2025. Notwithstanding, high-volume missile launchers would be 

introduced into a larger proportion (almost two-thirds) 

of Army combat brigades. The potential for cost growth 

under Alternative 2 is also more favorable than under the 

Administration’s plan—34 percent versus 60 percent. (If 

costs grew as they have in the past, acquisition costs under this alternative could be as high as $142 billion, compared with $231 billion for the full FCS program and 

planned upgrades.) Because the Army would invest significantly in upgrades under this approach, the average 

age of the resulting armored combat vehicle fleet would 

be much lower than that resulting under the Administration’s plan (see Summary Figure 2 on page xvii). In addition, this alternative would achieve survivability by means 

other than dependence on what could be a problematic 

network.

In emphasizing systems that would improve the Army’s 

ability to carry out long-range strikes, this alternative 

would not compare favorably with the Administration’s 

plan on at least two counts. First, the Army would indefinitely retain armored vehicles that were originally designed in the 1970s or earlier, which could make it difficult to integrate those vehicles into a network that would 

tie them and the FCS sensors and launchers together. 

Second, under this alternative, the Army would increase 

the weight and bulk of its heavy units as trucks to support 

the UAVs and missile launchers from the FCS program 

were added to each brigade. As with the previous alternative, that would mean an increase—in this case, one 

day—in the time needed to deploy a heavy brigade by air 
XXIV THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

but no increase in the time required to deploy it by sea 

(see Summary Table 3 on page xix).

Alternative 3. Emphasize Investment in New 

Manned Combat Vehicles

The third alternative envisions that the Army will develop 

and procure five types of manned vehicles through the 

FCS program to replace the oldest of its combat vehicles—the M113-based vehicles and M109 howitzers—

currently assigned to combat brigades (see Summary Table 4 on page xxi). The FCS components would address 

at least some of the problems—such as the inability of the 

M109 howitzers to keep up with the newer models of the 

Abrams tank and Bradley fighting vehicle—that the 

Army has said are associated with keeping the older vehicles in its combat units. The Army’s other armored vehicles (the Abrams tanks and Bradley fighting vehicles and 

those M113-based vehicles and M109 howitzers in units 

outside of heavy combat brigades) would be retained and 

upgraded so that they could be integrated into a scaleddown FCS network, which is another element of this alternative. All other parts of the FCS program—specifically, all four classes of UAVs, all unmanned ground vehicles, the non-line-of-sight launch system, the unattended 

ground sensors, the intelligent munitions system, and the 

remaining three types of manned FCS vehicles—would 

be canceled (see Summary Table 4 on page xxi).

CBO estimates that costs under this alternative will be 

similar to those under the previous two alternatives, requiring a total investment (excluding cost growth) of 

$103 billion from 2007 through 2025. Of that total, 

$67 billion would be needed to develop the five variants 

of manned vehicles and purchase 23 brigades’ worth of 

equipment by 2025. Upgrading the armored vehicles retained under this alternative would cost $35 billion from 

2007 through 2025 (see Summary Table 5 on page xxii).

Because the manned vehicles are among the most technically challenging of the FCS components and require 

the longest time to develop, purchases of those systems 

under this alternative would not begin until 2014. 

Consequently, the annual funding required would be 

less than that required under the previous two alternatives 

and the Administration’s plan—until 2015 (see Summary 

Figure 1 on page xiv). Furthermore, because manned vehicles represent the most expensive of the 18 FCS components, their annual purchases would be limited to two 

brigades’ worth, one fewer than under the previous two 

alternatives. Nevertheless, annual costs for this option, at 

roughly $6.5 billion, would be slightly greater than those 

under the previous two alternatives after 2015 but still 

significantly less than those under the Administration’s 

plan. 

Among the approaches CBO considered, this alternative 

is unique in its introduction of new vehicular technology 

into the Army’s forces. Because new armored combat vehicles would be introduced more quickly under this alternative than under any other—including the Administration’s plan—some of the Army’s oldest armored vehicles 

would be retired earlier, and the average age of the resulting fleet would ultimately be the lowest (see Summary 

Figure 2 on page xvii). The alternative’s costs are on a par 

with those of Alternatives 1 and 2; they are less than those 

of the Administration’s plan. But because this alternative 

would emphasize the development and procurement of 

ground vehicles, which have experienced the highest rate 

of historical cost growth, the potential for such a rise in 

costs is greater—at 55 percent—than under the previous 

two alternatives and could add $57 billion to total costs.

This alternative shares some disadvantages with Alternatives 1 and 2. Under this approach, the Army would indefinitely retain both the Abrams tank and Bradley fighting vehicle fleets—whose original designs date from more 

than 30 years ago—and would attempt to incorporate the 

technology associated with the FCS network into those 

vehicles, a plan that could pose technical difficulties. 

Moreover, implementing the alternative would have little 

effect on units’ deployment. On average, FCS vehicles 

would replace about half of the armored vehicles now in a 

heavy brigade; roughly 90 percent of those existing vehicles would be M113-based systems—which weigh less 

than the FCS vehicles that would replace them. As a result, the total weight of a heavy brigade could increase by 

as much as 6 percent under this alternative and in turn 

add one day to the time it would take to deploy such a 

brigade overseas by air. However, the time required to deploy either a brigade- or division-sized unit by sea would 

not increase (see Summary Table 3 on page xix).

Alternative 4. Develop a Scaled-Down FCS Network 

and Integrate It with Existing Systems

The last alternative that CBO examined would preserve 

only that portion of the FCS program designed to develop and support the network (see Summary Table 4 on 

page xxi). The new capability—a scaled-down version of 

the network currently envisioned for the FCS program—

would then be incorporated into existing armored vehi-
SUMMARY XXV

cles, allowing the Army’s combat brigades to benefit from 

an evolutionary improvement rather than a wholesale 

makeover based on unproven technology. All other portions of the FCS program would be canceled.

Under Alternative 4, the Army would purchase the least 

amount of hardware, by comparison with that purchased 

under the other alternatives, and would incur the lowest 

costs—$68 billion from 2007 through 2025. CBO estimates that $30 billion of that total will be needed to develop and purchase the hardware for the FCS network 

and that costs to upgrade the Army’s existing armored vehicles will be $38 billion (see Summary Table 5 on 

page xxii). Some of the capabilities of the FCS network 

would be incorporated into the Army’s current fleet of vehicles under this alternative, but the survivability of those 

vehicles would not be at risk if the network failed to perform as planned. Despite the fact that three brigades’ 

worth of FCS network hardware would be purchased annually starting in 2012, the annual funding needed to 

implement this alternative would be roughly $3 billion in 

2018 and thereafter (see Summary Figure 1 on page xiv). 

Under this alternative, the Army would have purchased 

enough network hardware by 2025 to upgrade almost 

two-thirds of its combat brigades. Moreover, because the 

Army would not develop or purchase any FCS components with high historical rates of cost growth, the potential for such growth under Alternative 4 would be relatively low—about 40 percent, or a total additional cost of 

$26 billion.

The speed of deployment of Army units overseas would 

be unaffected under this alternative because no new 

weapon systems would be added to existing Army combat 

brigades and no existing systems would be replaced by 

new ones. The time needed to deploy a heavy brigade 

overseas by air or by sea would be the same as it is for brigades equipped with existing armored vehicles—23 days 

and 25 days, respectively. Similarly, there would be no 

change in the time needed to deploy a division-sized unit 

by sea, which would remain at 27 days (see Summary Table 3 on page xix).

Because this alternative calls for so little investment in 

new technologies and equipment, it would also offer the 

fewest benefits from innovation, relative to the other approaches. Even though upgrades would maintain the average age of the Army’s fleet of armored vehicles at about 

13 years through 2040 and the vehicles would be connected by a new network, they would still be the same 

systems that the Army has had for the past 20 years. And 

some of them—notably those based on the M113 chassis—have been in the Army’s armored combat vehicle 

fleet since the Korean War.

CHAPTER

1

The Army’s Heavy Forces and Armored Vehicles 

The Army has long maintained a sizable force 

equipped with armored vehicles that were seen as particularly necessary during the Cold War to deter or defeat the 

extensive armored forces of the Soviet Union. (Units 

equipped with armored vehicles are referred to as “heavy” 

units; the rest of the Army’s combat forces are referred to 

as “light” units.) Since the fall of the Berlin Wall, some 

analysts have questioned the military relevance of armored forces; nevertheless, heavy units figured prominently in the opening days of ground combat in both 

Operation Desert Storm and Operation Iraqi Freedom. 

And they continue to be useful in other types of operations, such as the ongoing military activities in Iraq.

At the end of 2003, before the Army began its current reorganization initiative, the service maintained a fleet of 

more than 30,000 armored vehicles to equip and support 

the heavy units that made up roughly 50 percent of its 

combat forces. Almost half of those vehicles had been 

bought between 1980 and 1990 as part of the substantial 

investment in weapons known as the Reagan defense 

buildup; the remainder were first introduced in the 

1960s. Thus, the original design of the Army’s armored 

vehicles is decades old, although all of them have been 

upgraded and overhauled at least once since they were 

first placed in service.

Despite that ongoing modernization, which in many instances produces what is essentially a new vehicle, the average age of the Army’s current armored combat vehicle 

fleet is relatively high, and the status of that fleet has 

prompted concerns among the Army’s leadership. Perhaps most pressing is the fact that the weight and size of 

some armored vehicles prohibit them from being easily 

transported by air. For all practical purposes, heavy combat units (divisions and brigades or, before the Army’s reorganization, brigade combat teams) must be transported 

overseas by ship, a process that takes weeks.1

 In an era of 

rapidly evolving conflicts, the Army wants forces that 

have the combat power of heavy units but that can be 

transported anywhere in the world in a matter of days.

To address those concerns, the Army has undertaken two 

initiatives. The first—called modularity—would reorganize all of the Army’s combat forces into smaller, more 

standardized units. That process, when completed, will 

allow the service to reduce the overall size of its armored 

fleet and retire some of its older armored vehicles. The 

second initiative, the Future Combat Systems (FCS) program, is a major modernization effort designed in part to 

develop and purchase a total of 18 new weapon systems, 

including eight manned vehicles, to replace most of the 

armored systems now used in heavy units. The new vehicles would be much lighter than many of those the Army 

has now, which would make units equipped with them 

easier to deploy. 

But the Army’s plans for the FCS program raise additional issues. The new FCS vehicles would be lighter, but 

they would also be more expensive—because of the sophisticated communications gear, sensors, and active protection devices that would replace the extra weight of armor to ensure the vehicles’ survivability. Because of the 

cost, the Army plans to buy fewer than 500 manned FCS 

vehicles each year starting in 2015 at the earliest. Consequently, some of the vehicles now in the Army’s heavy 

units will be kept in the force for at least 30 more years—

long after the end of their useful service life.

Adding to concerns that the FCS program raises about retaining already aging vehicles for extended periods are 

1. A heavy brigade combat team included between 3,000 and 5,000 

soldiers, roughly 300 armored vehicles, and various support units. 

In 2003, the Army put together such teams for specific operations; 

they are currently being replaced by heavy modular units. (See the 

discussion in Chapter 2.) Also in 2003, a heavy division, with 

roughly 15,000 soldiers, typically included three brigade combat 

teams and additional support units.
2 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Figure 1-1.

The Army’s Armored Combat Vehicle 

Fleet, 1980 to 2003

(Thousands of vehicles)

Source: Congressional Budget Office based on data from the 

Department of the Army.

questions about the initiative’s technical feasibility and affordability. Some experts, including the Government Accountability Office (GAO), doubt whether the Army can 

develop and test the technologies necessary to start producing lightweight manned vehicles by 2012—the schedule that must be met to begin fielding the vehicles in December 2014, as the Army now plans.2

 (The fielding date 

has slipped seven years since the program was initiated in 

2000.) Another concern is the availability of funds to 

purchase FCS components in the quantities currently envisioned—1.5 brigades’ worth of equipment annually 

(which represents a reduction from the Army’s original 

plan of three brigades’ worth). The Army plans a force 

structure that includes a total of 27 heavy brigades; any 

further drop in the FCS procurement rate will force the 

service to retain its current fleet of armored vehicles 

longer and to invest more funds in maintaining and upgrading it. 

This Congressional Budget Office (CBO) study examines 

the Army’s FCS program and the concerns it has generated. The report considers the status of the Army’s fleet of 

armored vehicles in 2003 and in the future and assesses 

the ease of deployment of the Army’s heavy forces. In addition, it describes the FCS program; explores its costs, 

advantages, and disadvantages; and compares it with several alternative plans for modernizing the Army’s heavy 

forces.

Overview of the Army’s Armored

Vehicle Fleet at the End of 2003

The Army’s armored combat vehicle fleet—composed 

primarily of tanks, fighting vehicles, personnel carriers, 

and self-propelled howitzers—has shrunk since 1995, but 

at the end of 2003, it still included almost 32,000 vehicles of various types (see Figure 1-1). Almost all of them 

have been modernized since they were first produced; 

nevertheless, in 2003, several thousand of them were 

18 years old or older. Furthermore, at the end of 2003, 

the average age of the fleet was roughly 12 years, which 

exceeds the Army’s preferred level.3

Types of Vehicles in the Fleet

Armored combat vehicles are designed to protect soldiers 

as they attack the enemy, move about the battlefield, perform scouting or reconnaissance missions, or transport 

ammunition and other cargo to forces in hostile environments. The armored vehicle fleet mainly comprises just a 

few types of vehicles: those noted above (specifically, the 

Abrams tank, the Bradley fighting vehicle, the M113 armored personnel carrier, and the M109 self-propelled 

howitzer) and multiple-rocket launchers. Except for the 

rocket launchers, those types of armored vehicles are all 

found in the Army’s combat brigades; the service expects 

2. Statement of Paul L. Francis, Director, Acquisition and Sourcing 

Management, Government Accountability Office, before the Subcommittee on AirLand of the Senate Committee on Armed Services, published as Government Accountability Office, Defense 

Acquisitions: Future Combat Systems—Challenges and Prospects for 

Success, GAO-05-442T (March 16, 2005); and Government 

Accountability Office, Defense Acquisitions: Improved Business Case 

Is Needed for Future Combat System’s Successful Outcome, GAO-06-

367 (March 2006). 

1980 1985 1990 1995 2000

0

10

20

30

40

50

Bradley Fighting

Vehicles

M113-Based Vehicles

Abrams Tanks

M109 Self-Propelled

Howitzers

3. The Department of Defense aims to maintain the average age of 

its fleets of aircraft and vehicles at or below half of their useful life 

span. (For a discussion of desired fleet age, see Congressional Budget Office, The Long-Term Implications of Current Defense Plans, 

January 2003.) At various times, the Army has defined the useful 

life of its armored vehicles as 20 or 30 years, yielding desired halflives of 10 or 15 years. The Army’s preference is to prevent the 

average age of the fleet from exceeding 10 years.
CHAPTER ONE THE ARMY’S HEAVY FORCES AND ARMORED VEHICLES 3

Table 1-1.

Characteristics of Models of the M1 Abrams Tank in 2003

Source: Congressional Budget Office based on its February 1993 report Alternatives for the U.S. Tank Industrial Base and Gary W. Cooke, 

“Gary’s Combat Vehicle Reference Guide,” available at www.inetres.com/gp/military/cv/index.html.

Note: IP = Improved; n.a. = not applicable; NBC = nuclear, biological, and chemical.

to replace those systems with variants of the manned vehicles being developed as part of the FCS program.

Abrams (M1) Tank. This weapon system was developed 

in the 1970s, during the height of the Cold War, when 

defeat of the Soviet Union’s armored forces was of premier importance. During the 1980s and 1990s, the tank’s 

design underwent changes intended to enable it to attack 

targets from greater distances or to penetrate thicker armor. Subsequent modifications have generally included 

improved and heavier armor for greater protection and 

improved electronic and communications equipment (see 

Table 1-1 and Figure 1-2).4 The latest version of the tank 

weighs more than 70 tons and is so large and heavy that 

the Air Force’s newest cargo aircraft, the C-17, can carry 

only one Abrams tank at a time; the largest transport aircraft in the U.S. fleet, the C-5, can carry only two. At the 

end of 2003, the Army’s Abrams tank fleet was a mix of 

three models with an average age of roughly 13 years and 

totaling approximately 5,850 vehicles.

Bradley Fighting Vehicle. Developed at the same time as 

the Abrams tank, the Bradley fighting vehicle was designed to replace at least some of the service’s older M113 

armored personnel carriers. The Bradley is equipped with 

a 25-millimeter (mm) gun; tube-launched, optically 

tracked, wire-guided (TOW) antitank missiles; and a 

7.62-mm machine gun (see Figure 1-3).5

 The design of 

the vehicle has undergone many changes since it was introduced in 1981, including an improved version of the 

TOW missile system and enhanced protection of the 

crew and passengers (see Table 1-2 on page 6). The Army 

has produced very few new Bradley fighting vehicles since 

1995, but upgrades to existing vehicles have yielded a 

fleet with an average age of 10 years in 2003—which is 

considerably lower than the original production dates of 

1980 to 1994 would indicate. Even though the Bradley 

fighting vehicle weighs less than one-half as much as an 

Abrams tank, it, too, can be airlifted only by a C-17 or a 

C-5 and has been most commonly transported overseas 

by ship.

M113-Based Vehicles. The Army began developing the 

original M113 in 1956 as a lightweight multipurpose 

Date of Introduction 1985 1985 1991

Combat Weight (Tons) 61 67 70

Size of Main Gun (Millimeters) 105 120 120

Improvements Over Previous Model

Armor n.a.

Other n.a.

Status of Fleet in 2003

Number of vehicles 764 4,294 790

Average age (Years) 17 14 3

A2

depleted-uranium armor

Commander's independent

Active NBC protective system thermal viewer

Improved suspension

Digital electronics

IP A1

Model

Improved composite armor Second-generation

4. Appendix A describes in more detail the various models of the 

Abrams tank and of the Army’s other armored vehicles. 

5. The Bradley fighting vehicle has been produced in two variants, 

but the differences between them are minor. Because of the kind 

of missions it undertakes, the M3 cavalry fighting vehicle carries 

more radios and missile rounds than does the M2 infantry fighting vehicle, which can carry more soldiers (in addition to the crew 

of three, six versus two for the M3).
4 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Figure 1-2.

Abrams Tank

Source: Gary W. Cooke, “Gary’s Combat Vehicle Reference Guide,” 

available at www.inetres.com/gp/military/cv/index.html.

personnel carrier (see Figure 1-4). Since then it has 

fielded the vehicle in several versions, including as a 

smoke generator, mortar carrier, cargo carrier, command 

post, antitank-missile carrier, and personnel carrier. The 

most numerous of the Army’s armored vehicles, with 

roughly 18,000 in service at the end of 2003, the M113 

is also the Army’s only armored vehicle that weighs less 

than 20 tons—which makes it considerably lighter than 

either the Abrams tank or the Bradley fighting vehicle. 

Since it was first introduced, the M113 vehicle has been 

modified several times—for example, by switching the 

vehicle’s engine from gasoline to diesel fuel, improving its 

suspension and transmission, and adding an antispall 

liner (to protect occupants and equipment from hull fragments; see Table 1-3 on page 7). Although the Army has 

produced no new M113s since 1992, it has continued to 

convert older models to newer configurations—with the 

result that the average age of the M113 fleet at the end of 

2003 was only slightly greater than 13 years.

M109 Self-Propelled Howitzer. The howitzer, part of the 

Army’s inventory since 1963, provides supporting fire for 

the Army’s combat units; its 155-mm cannon can shell 

targets at distances of up to 30 kilometers (km), or approximately 20 miles (see Figure 1-5 on page 8). Weighing roughly 30 tons, the howitzer is the largest of the 

Army’s current fleet of armored vehicles and has been 

modified several times, but only the most recent upgrade 

represented a significant change. That conversion of older 

howitzers to the A6, or Paladin, configuration added supplemental armor and an antispall liner, enhanced the vehicle’s suspension and its hydraulic and electrical systems, 

and installed a new fire-control computer (see Table 1-4 

on page 9). Those extensive modifications, combined 

with the decommissioning of many older models in the 

mid-1990s, resulted in an average age for the howitzer 

fleet at the end of 2003 of 11 years.

Armored Combat Vehicles in the Army’s Current 

Force Structure

The armored vehicles described above are found primarily in the Army’s combat divisions and brigades. At the 

end of 2003, those units were more heavily represented in 

the Army National Guard than in the Army’s active component (see Table 1-5 on page 10).6

 At that time, six of 

the active component’s 10 divisions and seven of the National Guard’s eight divisions were equipped with armored vehicles. Other units so equipped included one armored cavalry regiment (ACR) in the Army’s active 

component and seven separate brigades and one ACR in 

the National Guard.

The Army had more than enough armored vehicles in its 

fleet at the end of 2003 to fully equip its heavy units— 

even if some of those vehicles were relatively old. The surplus was primarily due to the reduction in forces in the 

early 1990s, when the Army eliminated about one-third 

of its force structure and personnel but retained many of 

the vehicles it had purchased in the 1980s to equip a 

much larger force. The service’s total requirements for armored vehicles, however, encompass more than those 

needed to equip units in the force structure. Vehicles are 

also needed at various locations for training soldiers in 

their use and maintenance and for replacing vehicles that 

are removed from units for repairs or upgrades or that are 

lost in accidents or in combat. The factors that the Army 

uses for its planning indicate a range of 13 percent to 

20 percent of the total number of vehicles in units as the 

number of additional vehicles needed for training and replacements.7

 In its estimates of the number of additional 

6 ft.

6. The Army announced early in calendar year 2004 that it would 

reorganize its forces into so-called modular units. The discussion 

in this chapter describes the premodular Army—that is, before the 

reorganization. Chapter 2 describes modularity and its implications for the armored vehicle fleet.

7. Colonel Larry Hollingsworth, “Combat Systems—Where We Are 

. . . Where We’re Going. . . ” (presentation to the National 

Defense Industrial Association, Combat Vehicle Conference, Fort 

Knox, Ky., September 20–22, 2005).
CHAPTER ONE THE ARMY’S HEAVY FORCES AND ARMORED VEHICLES 5

Figure 1-3.

Bradley Fighting Vehicle

Source: Gary W. Cooke, “Gary’s Combat Vehicle Reference Guide,” 

available at www.inetres.com/gp/military/cv/index.html.

vehicles required to equip and support the Army’s units, 

CBO used an assumption of 15 percent. 

In addition, the Army maintains sets of equipment for 

heavy units in various places around the world, allowing 

soldiers to fly from their home station—generally in the 

United States—and collect their equipment at locations 

overseas. That policy of prepositioning equipment was 

first used in Central Europe, where the Army maintained 

six divisions’ worth in case of a major Soviet attack on 

Western Europe. Since the end of the Cold War, most of 

those stocks have been retired or redistributed to form 

several smaller sets of equipment located around the 

world. Before Operation Iraqi Freedom, equipment for 

five combat brigades was stored in South Korea, the Middle East, Europe, and onboard ships, adding to the overall 

inventory of equipment required for the Army’s heavy 

units (see Table 1-6 on page 12).

To equip, maintain, and support the heavy combat force 

that existed at the end of 2003, the Army needed roughly 

4,650 Abrams tanks, 5,650 Bradley fighting vehicles, 

11,650 M113-based vehicles, and 1,350 M109 selfpropelled howitzers, CBO estimates. At that time, the 

service’s inventories included roughly 5,850 tanks, 6,650 

fighting vehicles, almost 18,000 M113-based vehicles, 

and about 1,500 howitzers—more than enough to equip 

and fully support its heavy forces.

Issues Regarding Today’s Armored 

Forces and Vehicles

In recent years, defense officials and independent observers have voiced concerns about the Army’s existing armored vehicles and its heavy units. Predominant among 

such issues are the vehicles’ weight and their extensive 

support requirements (which make heavy units difficult 

to move overseas quickly) and the average age of the current armored combat vehicle fleet. Two other aspects of 

the current fleet also trouble Army leaders, factors that 

are linked to the continual upgrading and modernization 

that the vehicles have undergone since their introduction. 

One is that as the vehicles have been modified and improved, they have become heavier and less fuel efficient. 

The other is the mixture of models of each type of vehicle 

in the Army’s fleets, which increases the burden of maintenance and training associated with them.

Heavy Vehicles and Units are Difficult to Deploy

In its official statements, the Army has stressed the importance of a quick response to crises anywhere in the 

world. As noted earlier, however, it is impractical, if not 

infeasible, to transport the Army’s heavy units, with their 

hundreds of armored vehicles, by air. Consequently, 

when heavy units are deployed overseas, they are typically 

transported on ships, and because a transoceanic voyage 

takes several days, if not weeks, deployment by sea can be 

a lengthy process.

Figure 1-4.

M113 Armored Personnel Carrier

Source: Gary W. Cooke, “Gary’s Combat Vehicle Reference Guide,” 

available at www.inetres.com/gp/military/cv/index.html.

Note: This is the vehicle that forms the basis for the M113 family of 

vehicles.

6 ft.

6 ft.
6 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Table 1-2.

Characteristics of Models of the M2/M3 Bradley Fighting Vehicle in 2003

Source: Congressional Budget Office based on Gary W. Cooke, “Gary’s Combat Vehicle Reference Guide,” available at www.inetres.com/gp/

military/cv/index.html.

Note: n.a. = not applicable; FLIR = forward-looking infrared; TOW = tube-launched, optically tracked, wire-guided; NBC = nuclear, biological, and chemical.

a. Includes improvements and inventory for A2 Operation Desert Storm models.

b. The liner protects vehicle occupants from hull fragments.

Deploying Heavy and Light Army Units. The equipment 

found in the Army’s heavy units and that found in its 

light units differs substantially, and that divergence allows 

light units to be more easily deployed. Not only do the 

Army’s light divisions have no armored combat vehicles 

but they have roughly 50 percent fewer vehicles overall 

than heavy divisions have (see Table 1-7 on page 13). 

Moreover, at least two-thirds of the trucks in light divisions are high-mobility multipurpose wheeled vehicles 

(HMMWVs), the smallest of the Army’s trucks. It is thus 

realistic to assume that a light division’s equipment could 

be transported by air to remote airfields if the need 

arose.8

In contrast, heavy divisions, equipped with roughly twice 

as many vehicles as light divisions, are typically moved by 

sea. Their additional equipment primarily comprises 

hundreds of armored vehicles and heavy and mediumweight trucks (see Table 1-7 on page 13).9

 Furthermore, 

as noted earlier, most of the armored vehicles are so large 

and heavy that they must be transported not by the Air 

Force’s large fleet of C-130 aircraft but by its less numerous but bigger C-17s or C-5s—aircraft that require bigger and better-prepared landing facilities. As a result, in 

many cases, moving even a heavy brigade combat team 

(roughly equivalent to one-third of a division) by air is 

impractical.

The time and the ships or aircraft required to transport 

Army units from the United States to Djibouti, a small 

nation on the coast of East Africa, illustrate why some 

Army leaders consider today’s heavy units too cumberDate of Introduction 1981 1988 1999

Combat Weight (Tons) 25 32 33

Improvements Over Previous Model

Armor n.a.

Other n.a.

Status of Fleet in 2003

Number of vehicles 1,517 4,793 349

Average age (Years) 19 7 1

Model

NBC filter system

Titanium roof armor

Second-generation FLIR for

viewer and driver's vision 

commander's independent

Additional appliqué armor

Digital communications

Antispall linerb

Improved TOW missile

enhancer

A0 A2a A3

system

8. In fact, the 82nd Airborne Division and two light infantry divisions were designed for just such a contingency, and portions of 

the 82nd Airborne and the 10th Light Infantry divisions have 

been flown into Afghanistan to participate in operations there. In 

addition, a brigade of the 82nd Airborne Division is always on 

alert and ready to be airlifted to a crisis anywhere in the world.

9. Compared with an airborne division, an armored division has over 

a thousand more trucks but is equipped with roughly the same 

number of HMMWVs. The armored division’s additional trucks 

include roughly 600 medium-sized trucks (each weighing 10 tons 

to 13 tons) and 350 heavy trucks (each weighing roughly 20 tons).
CHAPTER ONE THE ARMY’S HEAVY FORCES AND ARMORED VEHICLES 7

Table 1-3.

Characteristics of Models of M113-Based Vehicles in 2003

Source: Congressional Budget Office based on Gary W. Cooke, “Gary’s Combat Vehicle Reference Guide,” available at www.inetres.com/gp/

military/cv/index.html; and Christopher Foss, ed., Jane’s Armour and Artillery, 1979-1980 (New York: Wyatt Publishing, 1979).

a. The liner protects vehicle occupants from hull fragments.

some. (Djibouti—7,700 miles from the East Coast of the 

United States—has strong military ties to the United 

States and according to the Central Intelligence Agency is 

“a frontline state in the global war on terrorism.”)10

Deploying Forces to Djibouti by Air. In transporting a large 

amount of equipment to Djibouti by air, the Army faces 

certain constraints. Djibouti’s transportation infrastructure is limited: for example, only three of its airports have 

paved runways. If those airports were extensive, with 

many taxiways and large aprons, the Air Force’s planned 

fleet of 180 C-17s could support 65 sorties per day capable of delivering roughly 3,000 tons to 4,000 tons of 

equipment.11 That level of capacity would mean that the 

Army could move light infantry or airborne brigade combat teams from the United States to Djibouti by air in 

only one or two days; it could move a light infantry division or an airborne division in roughly one week. Theoretically, even an armored brigade combat team could be 

moved in seven days (see Figure 1-7 on page 14). 

However, the type of facilities needed to handle the number of daily sorties required to deliver up to 4,000 tons of 

equipment are found only at very large airports, such as 

those at Ramstein Air Force Base in Germany. None of 

the airports in Djibouti is big enough to handle the number of aircraft that would be on the ground at one time if 

65 C-17s were arriving and departing each day. In fact, 

most airports in places in which crises are likely to occur 

would have space for only a few C-17s unloading and being serviced at the same time. In that case, the number of 

daily C-17 sorties would be limited to fewer than 20, 

even with 24-hour operations, and the amount of equipment delivered to Djibouti in one day would be reduced 

to between 1,000 tons and 1,200 tons. At that rate, transporting an armored brigade combat team by air would

Date of Introduction 1979 1986

Combat Weight (Tons) 12 14

Improvements Over Previous Model

Armor

Other

Status of Fleet in 2003

Number of vehicles 11,654 6,185

Average age (Years) 15 10

A3

Model

A2

Not applicable

Antispall linera

Provisions for bolt-on armor

Greater horsepower diesel engine

Improved transmission

Automotive-type steering and brake controls

Diesel engine

Improved suspension

10. See the entry on Djibouti in the Central Intelligence Agency’s 

The World Factbook, available at www.cia.gov/cia/publications/

factbook/index.html.

11. The range in the amount of equipment delivered by the same 

number of sorties reflects the fact that C-17s loaded with heavy 

equipment, such as tanks, can carry more tonnage per sortie than 

they can when transporting equipment from light units because 

the heavy vehicles that will fit in the aircraft weigh more. According to an analysis by the Department of Defense’s Military Transportation Command, C-17s that transport equipment from heavy 

units carry an average of 60 tons per sortie; those that deliver 

equipment from light units have an average payload of 50 tons or 

less. (Appendix B describes how CBO estimated the time needed 

to move units overseas by air.)
8 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Figure 1-5.

M109 Self-Propelled Howitzer

Source: Gary W. Cooke, “Gary’s Combat Vehicle Reference Guide,” 

available at www.inetres.com/gp/military/cv/index.html.

take 23 days. For sustained operations, total daily deliveries would be reduced to less than 800 tons, and it could 

take more than 100 days to deliver an armored division 

(see Figure 1-7 on page 14).12

Another critical factor is that those estimates of deployment times incorporate the assumption that the Air 

Force’s entire C-17 fleet is devoted to ferrying the heavy 

units’ equipment from the United States to Djibouti. In 

an actual conflict, the Air Force would have other responsibilities as well, including transporting equipment for its 

own needs, for large air-defense systems, and for other 

purposes (such as opening ports or handling materiel arriving at airfields). In past conflicts, the Army has received substantially less than 100 percent of the United 

States’ airlift capacity to move equipment associated with 

its combat units.

Deploying Forces to Djibouti by Sea. Moving equipment by 

sea, particularly heavy and bulky equipment, is a viable 

and sometimes attractive alternative to moving it by air. 

Djibouti, for example, has one large port that can accommodate large seagoing vessels, including the fast sealift 

ships (FSSs) and large medium-speed roll-on/roll-off 

ships (LMSRs) operated by the Military Sealift Command (MSC) to transport U.S. forces overseas.13 The estimated time such ships would require to deliver their 

cargo to Djibouti—which includes readying the ships, 

moving Army units from their home stations to a port 

such as Savannah, loading the ships, sailing to Djibouti, 

and unloading the ships—is 25 days (for FSSs) and 

27 days (for LMSRs).14

The MSC’s fleet of eight FSSs and 11 LMSRs is more 

than adequate to move any one of the Army’s divisions in 

one sailing. In fact, the FSS fleet alone could move a light 

division or even a heavy brigade combat team. However, 

the equipment associated with a heavy division would require more capacity than could be provided by FSSs 

alone. Consequently, the time needed to deliver a full armored division would be two days longer than that required to deploy a light division—because of the slower 

speed of the LMSRs. All told, 25 days would be needed 

to deliver light units or a heavy brigade to Djibouti by 

sea, and 27 days would be required to deliver a heavy division (see Figure 1-7 on page 14).

Other Considerations. Another factor to take into account in estimating the time needed to deploy an Army 

unit overseas is that a division—and to a greater extent, a 

brigade—cannot operate for long in a theater (particularly an undeveloped one) without supporting units and 

supplies (including ammunition, fuel, food, water, and 

spare parts). Most units carry supplies for only a limited 

time—typically, three days for a brigade-sized unit. The 

air- or sealift capacity to bring in additional supplies and 

supporting units must be added to that required to deploy brigades and divisions themselves.

Heavy units need perhaps the most support of any of the 

Army’s forces. Armored vehicles, such as the Abrams tank 

and Bradley fighting vehicle, have very low fuel efficiency 

(they can travel less than 2 miles on a gallon of fuel). 

Consequently, heavy units in combat burn fuel at a high 

12. Expedited, or “surge,” operations (usually 24 hours a day) are generally sustained for limited periods—typically, 45 days—during 

the early stages of a crisis. After that, the level of effort is reduced 

to one that can be maintained indefinitely.

6 ft.

13. The ships in the MSC’s fleet can be ready in four days to be 

loaded with Army equipment. FSSs and LMSRs have average 

transit speeds of 27 knots and 24 knots, respectively.

14. CBO’s estimates of the time required to deploy units overseas 

cover only the time needed to deliver the unit’s equipment to an 

air- or seaport and not the time needed to reconstitute the unit or 

move it to a marshaling area away from the port. For a more 

detailed discussion of the assumptions and methods CBO uses to 

estimate deployment times by sea, see Congressional Budget 

Office, Options for Strategic Military Transportation Systems (September 2005), Chapter 2.
CHAPTER ONE THE ARMY’S HEAVY FORCES AND ARMORED VEHICLES 9

Table 1-4.

Characteristics of Models of the M109 Self-Propelled Howitzer in 2003

Source: Congressional Budget Office based on Gary W. Cooke, “Gary’s Combat Vehicle Reference Guide,” available at www.inetres.com/gp/

military/cv/index.html.

a. Date of introduction of the original M109 howitzer.

b. The liner protects vehicle occupants from hull fragments.

c. Includes only A4 and A5 models.

rate—about 420,000 gallons of fuel per day for a heavy 

division, according to one source.15 To meet such demands, each heavy division is equipped with about 170 

tankers, each holding 2,500 gallons—and the tankers also 

need fuel to perform their mission. That small example of 

the logistics burden associated with heavy units illustrates 

why it is difficult to deploy and operate them without a 

large support structure—an area of concern to Army 

leaders.

The Armored Combat Vehicle Fleet Is Aging 

More than half of the Army’s armored combat vehicles 

are based on systems that were introduced in the 1960s, 

and even the most recent models are based on technology 

that is roughly 25 years old. Moreover, despite the upgrades that almost all the vehicles have undergone since 

they were first produced, some of the individual fleets at 

the end of 2003 contained large numbers of very old vehicles. Specifically:

B More than 2,500 of the 5,850 Abrams tanks had been 

in service 15 years or more, and 540 tanks had been in 

service 18 years;

B Of the roughly 6,650 Bradley fighting vehicles in the 

fleet, 370 were 20 years old, and more than 1,500 

were at least 15 years old;

B More than half of the M113-based vehicles were produced or rebuilt at least 15 years ago, and almost 

1,000 had been commissioned 18 years earlier; and

B Almost 300 of the M109 self-propelled howitzers were 

at least 20 years old.

The average age of the entire armored combat vehicle 

fleet at the end of 2003—12 years—exceeded the Army’s 

preferred average age of 10 years. Furthermore, the 

average age of each of the individual fleets—except that 

of the howitzers—has been rising steadily since 1990 

(see Figure 1-6). The useful service lives of armored 

Date of Introduction 1962 a 1992

Combat Weight (Tons) 28 32

155 155

Improvements Over Previous Model

Armor

Other

Status of Fleet in 2003

Number of vehicles 542 c 975

Average age (Years) 19 6

Model

Onboard ballistic computer

Improved suspension

Antispall linerb

Supplemental armor

A2/A3/A4/A5 A6 (Paladin)

Not applicable

Not applicable

Driver's night-vision device

Size of Cannon (Millimeters)

Enhanced hydraulic and electrical systems

Enhanced engine cooling

15. Bryant Jordan and Sean Naylor, “Too Heavy,” Army Times (September 6, 1999), p. 14.
10 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Table 1-5.

Army Units Equipped with Armored 

Vehicles in 2003

Source: Congressional Budget Office based on Assistant Secretary 

of the Army for Financial Management and Comptroller, 

The Army Budget: FY04/05 President's Budget (February 

2003). 

vehicles may extend from 20 years to 30 years; however, 

unless the Army continues to invest significant amounts 

in upgrades or modifications, many of the vehicles that 

currently provide much of its combat power will reach 

the end of their useful lives in the next decade.

Armored Vehicles Are Getting Bigger and Heavier

The armored vehicles that make up the Army’s current 

fleet have grown heavier and larger as the service has 

modified and improved them. With the addition of armor and more-sophisticated electronic gear, the weight of 

succeeding models of each of the four types of armored 

vehicles has increased significantly over that of the corresponding original model.

B The weight of the Abrams tank has grown by more 

than 16 percent, rising from 60 tons when the basic 

version of the tank was introduced in 1981 to more 

than 70 tons for the latest model—which, in addition 

to more and heavier armor, is equipped with a larger 

main gun.

B The most recent version of the Bradley fighting vehicle weighs 33 tons, almost one-third more than the 

original vehicle introduced in 1981, which weighed 

25 tons.

B The weight of the M113 armored personnel carrier 

has grown from its original 12 tons in 1961 to 14 tons 

for the latest model.

B The M109 self-propelled howitzer has become 14 percent heavier—its weight rising from 28 tons to 32 

tons—with the fielding of the latest model in 1992.

The increase in weight has led, in general, to a decrease in 

fuel efficiency, which intensifies the logistics burden of 

supporting these vehicles in combat or in other operations. Another concern of the Army’s planners is that the 

latest model of the Abrams tank is too heavy for many 

bridges in Europe, particularly older ones. Moreover, 

both the Abrams tanks and the Bradley fighting vehicles 

are too wide (12 feet and 11 feet, respectively) for many 

roads in built-up areas. Thus, the size and weight of the 

Abrams tank in particular and, to a lesser extent, of the 

Bradley fighting vehicle limit the vehicles’ usefulness in 

constricted spaces (such as urban environments) or in 

areas where roads and bridges are not designed to carry 

very heavy or very wide loads.

Figure 1-6.

Average Age of the Army’s Armored 

Combat Vehicles, 1990 to 2003

(Average age in years)

Source: Congressional Budget Office based on data from the 

Department of the Army.

Armored and 

Mechanized Infantry 6 4 10

Infantry 0 3 3 _ _ __

Total 6 7 13

Armored 0 3 3

Mechanized Infantry 0 4 4

Armored Cavalry 1 1 2 _ _ __

Total 1 8 9

Divisions

Separate Brigades or Regiments

Army

Army's 

Guard

Active National Total

Component

Army

1990 1992 1994 1996 1998 2000 2002

0

5

10

15

20

25

M109 Self-Propelled Howitzers

Total Fleet

M113-Based Vehicles

Bradley Fighting Vehicles

Abrams Tanks
CHAPTER ONE THE ARMY’S HEAVY FORCES AND ARMORED VEHICLES 11

Each Armored Vehicle Fleet Comprises

Several Models

At the end of 2003, the Army’s armored vehicle fleets 

contained several different models of each type of vehicle—three models for the Abrams tank and for the Bradley fighting vehicle and two for the M113 and for the 

M109 fleets.16 Except in the case of the M109 howitzer, 

most of the vehicles in a given fleet at the end of 2003 

were not the latest model.

B The A1 model of the Abrams tank, introduced in 

1985, accounted for almost three-quarters of the tank 

inventory; the latest model, the A2, accounted for 

only 14 percent.

B Of the Bradley fighting vehicle fleet in 2003, the latest 

A3 model, introduced in 1999, represented only 

5 percent of vehicles, whereas the A2 model, introduced in 1988, accounted for the vast majority of the 

rest.

B The older A2 version of the Army’s M113-based vehicles, introduced in 1979, accounted for roughly twothirds of that fleet; the more modern A3 model accounted for the remainder.

B In contrast, most—64 percent—of the fleet of M109 

self-propelled howitzers were the updated A6 model 

introduced in 1992; the rest were older versions.

The reason that more of the Army’s armored vehicles 

are not the latest model may be the expense involved in 

converting older models to the most modern version. 

Converting an A1 model of the Abrams tank to the 

A2 model, for example, costs roughly $5 million. Converting A2 models of the Bradley and M113-based 

vehicles to the A3 model of each costs $4 million and 

$400,000, respectively.

Because the Army has not converted all of its armored vehicles to their most modern form, it cannot provide the 

same equipment to all of its heavy units. In 2003, the service did not have enough of its most modern Abrams 

tanks or Bradley fighting vehicles to equip all of the heavy 

units in the Army’s active component—which in the past 

have received the latest versions of equipment before 

units in the National Guard (see Figure 1-8 on page 15). 

The mix of models in the vehicle fleets means that some 

active-component units will have the latest models of armored vehicles (A2 versions of the Abrams tank, A3 versions of the Bradley fighting vehicle, and A3 versions of 

the M113 personnel carrier); other active-component 

units will have a mix of various models; and many units 

in the National Guard will have the oldest models in the 

fleet.

The lack of uniformity among models of the vehicles that 

equip active-component units and National Guard units 

may cause problems in deployments and operations. 

Some units may deploy without their own equipment 

and either pick up prepositioned items or retrieve equipment left behind by units that preceded them. If either 

the prepositioned or retrieved equipment is different 

from the vehicles that units have trained on or are familiar with, problems may develop in the field. Furthermore, 

a mismatch of equipment between active-component and 

National Guard units may make it difficult for units from 

the two components to operate effectively together.

In 2003, for example, roughly one-third of the heavy 

units in the Army’s active component were equipped with 

the A2 model of the Abrams tank, and the rest were 

equipped with the A1 version. In contrast, three-quarters 

of National Guard units were equipped with the A1 

model, and the rest had an older version—the Abrams 

IP—whose main gun is a smaller caliber than the guns on 

the two other models of the tank. Moreover, the sets of 

equipment prepositioned in the Middle East and onboard ship were equipped with the A1 model of the tank. 

Thus, both the Army’s active-component units and units 

from the National Guard might arrive in Iraq and be expected to use tanks with which they were not familiar.

16. That enumeration ignores variants of specific models—for example, it treats the Abrams A1 and Abrams A1 AIM as one model.
12 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Table 1-6.

Armored Vehicles Needed to Equip and Support the Army’s Heavy Units in 2003

Source: Congressional Budget Office based on information from the Department of the Army’s WebTAADS database (an Internet version of 

The Army Authorization Document System, or TAADS, maintained by the Army Force Management Support Agency’s Requirements 

Division) and the Operating and Support Management Information System (OSMIS).

Note: “Heavy” units are those equipped with armored vehicles.

a. Requirements for Abrams tanks, Bradley fighting vehicles, and M113-based vehicles are rounded to the nearest 50 vehicles for divisions 

and to the nearest 10 vehicles for brigades and regiments.

b. Rounded to the nearest 50 vehicles.

c. Represents vehicles needed at various locations for training soldiers in their use and maintenance and for replacing vehicles that are 

removed from units for repairs or upgrades or that are lost in accidents or in combat.

 

Divisions

Armored or mechanized infantry 250 300 500 54

Infantry 150 200 350 36

Separate Brigades or Regiments

Armored 100 60 190 18

Mechanized infantry 50 100 190 18

Armored cavalry 120 140 160 18

Combat Brigades and Divisions

Active component 1,600 1,950 3,150 350

National Guard 2,050 2,500 4,550 450

Other Units 0 0 1,500 300 ______ ______ ______ ______

Subtotal, vehicles in units 3,650 4,450 9,200 1,100

Prepositioned Equipment 450 550 1,050 100

Operational Readiness Float 

 and Training Basec 550 650 1,400 150 ______ ______ _______ ______

Total 4,650 5,650 11,650 1,350

M109 SelfPropelled

Abrams Tanks Fighting Vehicles Howitzers

Bradley M113-Based

Vehicles

All Armored Vehiclesb

Number of Armored Vehicles per Unita
CHAPTER ONE THE ARMY’S HEAVY FORCES AND ARMORED VEHICLES 13

Table 1-7.

Comparing the Army’s Light Infantry, Airborne, and Armored Units in 2003

Source: Congressional Budget Office based on data from the Department of the Army; and Military Traffic Management Command Transportation Engineering Agency, Deployment Planning Guide: Transportation Assets Required for Deployment, MTMCTEA Pamphlet 

700-5 (May 2001).

a. Includes all tracked armored vehicles.

b. Includes helicopters and wheeled vehicles that cannot drive long distances on roadways.

c. Based on a maximum allowable cabin load of 65 tons for a leg of 3,200 nautical miles and rounded to the nearest five sorties.

d. Either fast sealift ships or large medium-speed roll-on/roll-off ships will be needed but not both.

Personnel (Number) 12,100 13,500 17,300 2,700 3,100 3,800

Vehicles (Number)

10 10 1,560 0 0 450

Trucks 2,520 2,910 4,060 420 570 840

Towed 950 1,090 2,090 130 180 390

Otherb 130 220 130 10 10 10 _______ _______ _______ ______ ______ _______

Total 3,610 4,230 7,840 560 760 1,690

13,600 14,700 83,000 2,300 2,700 21,100

19,200 25,400 99,900 2,900 4,200 25,000

483 566 1,406 71 97 305

563 907 1,502 80 111 323

425 530 1,720 60 90 420

3.7 5.9 9.8 0.6 0.7 2.1

2.0 3.2 5.4 0.3 0.4 1.2

Infantry

Trackeda

Infantry Airborne Armored Airborne Armored

Divisions Brigade Combat Teams

Light Light

Weight (Tons)

All vehicles

Total for unit

Area Covered (Thousands of square feet)

Sealift (Number of ships)d

Fast sealift ships

Large medium-speed roll-on/roll-off ships

All vehicles

Total for unit

Deployment of Equipment

Airlift (Number of C-17 sorties)c
14 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Figure 1-7.

Time Needed to Deploy Equipment of Combat Units from the Continental United 

States to East Africa

(Days)

Source: Congressional Budget Office based on data from the Department of the Army; Military Traffic Management Command Transportation Engineering Agency, Deployment Planning Guide: Transportation Assets Required for Deployment, MTMCTEA Pamphlet 700-5 

(May 2001); and Department of the Air Force, Air Mobility Planning Factors, Pamphlet 10-1403 (December 18, 2003).

Note: The data do not reflect the time needed to move sustaining units or supplies.

a. “Unconstrained” and “constrained” refer to whether the number of daily sorties to deliver equipment is constrained (or not) by the airfield’s capacity to accommodate aircraft and handle cargo.

Light Infantry Airborne Armored Light Infantry Airborne Armored

0

20

40

60

80

100

120

Unconstrained Airlift Constrained Airlift Sealift

Brigade Combat Team Division

a a
CHAPTER ONE THE ARMY’S HEAVY FORCES AND ARMORED VEHICLES 15

Figure 1-8.

Requirements and Inventories for the Army’s Armored Combat Vehicles in 2003

(Thousands of vehicles)

Source: Congressional Budget Office.

Note: The “float and training base” category represents vehicles needed at various locations for training soldiers in their use and maintenance and for replacing vehicles that are removed from units for repairs or upgrades or that are lost in accidents or in combat. The 

“prepositioned” category represents sets of equipment located at various sites around the world that allow quick deployment of units.

a. Reflects vehicles in units outside of divisions and combat brigades.

Requirement Inventory

0

5

10

15

20

Requirement Inventory

0

1

2

3

4

5

6

7

Abrams Tanks

Active Units

Prepositioned

Float and

Training Base

National

Guard Units

Requirement Inventory

0

1

2

3

4

5

6

7

Bradley Fighting Vehicles

Active Units

Prepositioned

Float and

Training Base

National

Guard Units

M1 IP

M2/M3 A0

M2/M3 A2

M2/M3 A3

M113-Based Vehicles

Active Units

Prepositioned

Float and

Training Base

National

Guard Units

M1 A1

M1 A2

M113 A2

M113 A3

Requirement Inventory

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

0

National

Guard Units

Prepositioned

Float and

Training Base

Other Unitsa

A4/A5

A6

M109 Self-Propelled Howitzers

Other Unitsa

Active Units

CHAPTER

2

Description of the Army’s Modularity Initiative and 

Future Combat Systems Program

The changing global political environment has led 

the Army to undertake several initiatives that are designed 

to enable its forces to respond rapidly and capably to conflicts arising anywhere in the world. One of those plans, 

the modularity initiative, would reorganize the Army’s 

fighting forces into smaller, more standardized units so 

that they could be used interchangeably and in whatever 

combination was best suited to a particular crisis. Another initiative, the Future Combat Systems program, 

would develop and field a total of 18 new systems as well 

as a communications network. The FCS components 

would include several new unmanned air and ground vehicles and replacements for the armored vehicles in the 

Army’s current fleet (which were developed decades ago) 

featuring lighter platforms of entirely new design. The 

schedule for developing and fielding the FCS components has changed several times since the program began, 

and its ambitiousness together with the program’s complexity have raised questions about the program’s ultimate 

success.

The Modularity Initiative

In February 2004, the Army announced that it would restructure its combat forces to make them more agile and 

flexible. Until then, under the service’s so-called premodular structure, most of its combat forces had been organized into divisions that typically comprised three 

combat—or maneuver—brigades in addition to several 

support components, such as engineer units, artillery 

units, and signal units.1

 At the end of 2003, the Army’s 

combat forces included 10 divisions in the active component and eight divisions in the Army National Guard as 

well as several combat brigades and regiments outside 

those divisions.

That force structure, however, has not been well suited to 

some recent military operations. For example, once the 

situation in Bosnia and Kosovo had been stabilized and 

troops of the North Atlantic Treaty Organization had 

gained control, U.S. peacekeeping operations there required less than a full division’s worth of combat forces. 

As a result, one or two combat brigades from a division 

would be deployed, along with the division headquarters 

and other support units, for what would typically be a 

six-month rotation. After that, another brigade or two, 

often from a different division, would replace them. The 

Army found such reconfigurations of parts of divisions 

into smaller packages, or task forces, to be disruptive.

To create what Army Chief of Staff General Peter Schoomaker described in February 2004 as a more responsive 

and more easily deployable force, the service began restructuring its organization from one based on 18 divisions, several of unique design, to one based on 70 combat brigades, each one of only three designs. The Army 

also expects to restructure and standardize its division and 

corps headquarters units and the support units that had 

been assigned to the divisions and corps within its premodular force structure.

Comparing the Army’s Modular and Premodular 

Force Structures

The Army’s modularity initiative, if carried out as 

planned, will touch almost all aspects of its force structure. Although the service’s active component will retain 

its 10 division headquarters under the reorganization, it

1. An exception to that structure was the 10th Mountain Division, 

which had only two combat brigades in 2003.
18 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Table 2-1.

Comparing the Army’s Premodular and Modular Combat Force Structures

Source: Congressional Budget Office based on data from the Department of the Army and a private Army briefing, “The Army Modular

Force, 2004–2020” (July 2005).

Note: “Premodular” and “modular” refer to the Army’s ongoing modularity initiative, which seeks to make the service more flexible by 

changing its structure from one based on 18 divisions, several of unique design, to one based on 70 combat brigades, each one of only 

three designs.

a. Includes armored cavalry regiments and armored and mechanized infantry brigades. 

b. Includes light infantry, infantry, airborne, and air assault brigades as well as scout units.

c. Brigades that are equipped with medium-weight Stryker wheeled armored vehicles.

will alter the units associated with them.2 Divisions, 

which in the premodular Army were typically assigned 

three combat brigades, will have four such units associated with them in the modular Army. And combat brigades, which in the premodular Army comprised only 

combat units (such as infantry battalions and tank battalions), will now include some support units as well (such 

as artillery units and engineer units). In that way, the 

Army argues, each modular combat brigade will be more 

self-contained and able to operate more effectively on its 

own.

Modular combat brigades are designed to be the basic 

unit for carrying out the Army’s missions.3

 Most of the 

Army’s armored vehicles will be found in such brigades, 

and it is there that the new FCS vehicles will ultimately 

be assigned. Thus, the remainder of this discussion of the 

Army’s modularity initiative will focus on changes in its 

combat brigades and in particular on those brigades that 

contain armored vehicles.

Number of Heavy Brigades. As planned in early calendar 

year 2006, the Army will field fewer heavy brigades under 

its modular structure than under its premodular organization. At the end of 2003, the service had 41 heavy brigades—18 active-component units and 23 National 

Guard units (see Table 2-1). The Army is planning to

Heavya 18 23 41

Lightb 12 15 27

Strykerc 303 ___ ___ ___

Total 33 38 71

Heavy 19 8 27

Infantry 17 19 36

Strykerc 617 ___ ___ ___

Total 42 28 70

Modular Brigades Planned for 2011

Active Component Total Army

Army

National Guard

Premodular Brigades, End of 2003

2. The Army plans to reduce the number of division headquarters in 

the National Guard from the current eight to six by 2011. 

3. Under the modularity initiative, division support units will be 

organized into brigades (aviation, artillery, and support) that 

closely parallel those found in premodular divisions. Support units 

outside of divisions will also be organized into brigades (combat 

aviation; fires; combat support maneuver enhancement; battlefield surveillance; and sustainment). For a more complete discussion of the changes resulting from the Army’s initiative, see U.S. 

Army Training and Doctrine Command, Army Comprehensive 

Guide to Modularity, vol. 1, version 1.0 (October 8, 2004); Congressional Budget Office, Options for Restructuring the Army (May 

2005); and Andrew Feickert, U.S. Army’s Modular Redesign: Issues 

for Congress, CRS Report for Congress RL32476 (Congressional 

Research Service, May 5, 2006).
CHAPTER TWO DESCRIPTION OF THE ARMY’S MODULARITY INITIATIVE AND FUTURE COMBAT SYSTEMS PROGRAM 19

Table 2-2.

Comparing the Army’s Premodular Heavy Brigade Combat Teams and Modular 

Heavy Combat Brigades

Source: Congressional Budget Office based on data from the Department of the Army; Military Traffic Management Command Transportation Engineering Agency, Deployment Planning Guide: Transportation Assets Required for Deployment, MTMCTEA Pamphlet 700-5 

(May 2001); Department of the Army, Cost and Economic Analysis Center, FORCES Cost Model, Version 2003.0513; and Colonel 

Larry Hollingsworth, “Combat Systems—Where We Are . . . Where We’re Going. . . “ (presentation to the National Defense Industrial Association, Combat Vehicle Conference, Fort Knox, Ky., September 20–22, 2005).

Note: “Premodular” and “modular” refer to the Army’s ongoing modularity initiative, which seeks to make the service more flexible by 

changing its structure from one based on 18 divisions, several of unique design, to one based on 70 combat brigades, each one of only 

three designs.

a. Rounded to the nearest five vehicles.

b. Rounded to the nearest 10 vehicles.

c. Includes wheeled vehicles that cannot drive for long distances on roads. 

increase—from 33 to 42—the total number of combat 

brigades (of all types) in its active component. Of those 

42, 19 will be heavy brigades—one more than the number fielded under the premodular structure. At the same 

time, the service expects to reduce the number of combat 

brigades in the National Guard to 28 (according to its 

plans in March 2006), or 10 fewer than at the end of 

2003—a reduction that would come mostly at the expense of the Guard’s heavy units. Consequently, by 2011, 

with the reorganization complete and all units converted 

to the modular design, the Army would have 27 heavy 

combat brigades—14 fewer than it had in 2003. Furthermore, the Army’s active component in 2011 would have 

more heavy combat brigades than the National Guard 

would have, reversing the situation that prevailed at the 

end of 2003.

Brigade Design and Size. Under the premodular force 

structure, heavy combat brigades that were part of a division typically included about 2,000 soldiers. When engaged in an operation, a brigade would typically be augmented by artillery, engineer, cavalry, and other support 

units, creating what the Army terms a brigade combat 

team. With those additional units, a premodular heavy 

brigade combat team (one with armored or mechanized 

infantry units) would typically include about 4,000 soldiers (see Table 2-2).

A heavy combat brigade under the modular structure will 

have roughly the same number of soldiers but fewer 

“combat” units: only two combined arms battalions compared with the three combat battalions (tank or mechanized infantry) that are typically part of a premodular

Personnel 4,000 3,800 3,800

Vehicles

Trackeda

Abrams tanks 55 95 60

Bradley fighting vehicles 110 65 120

M113-based vehicles 190 190 120

M109 self-propelled howitzers 20 20 15

Other 75 80 50 ___ ___ ___

Subtotal, tracked vehicles 450 450 365

Trucksb 810 840 880

Towedb 390 390 410

Otherc 10 10 20 _____ _____ _____

Total 1,660 1,690 1,675

Premodular Brigade Combat Teams

Mechanized Infantry Armored Modular Heavy Brigade
20 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Table 2-3.

Armored Combat Vehicles Needed to Equip and Support the Army’s Modular 

Heavy Combat Brigades in 2011

Sources: Congressional Budget Office based on data from the Department of the Army’s WebTAADS database (an Internet version of The 

Army Authorization Document System, or TAADS, maintained by the Army Force Management Support Agency’s Requirements Division); U.S. Army Ground Combat Systems Program Executive Office, Fleet Management Strategy (June 2005); and Colonel Larry 

Hollingsworth, “Combat Systems—Where We Are . . . Where We’re Going. . . “ (presentation to the National Defense Industrial 

Association, Combat Vehicle Conference, Fort Knox, Ky., September 20–22, 2005).

Notes: Numbers are rounded to the nearest 50 vehicles.

“Premodular” and “modular” refer to the Army’s ongoing modularity initiative, which seeks to make the service more flexible by 

changing its structure from one based on 18 divisions, several of unique design, to one based on 70 combat brigades, each one of only 

three designs. 

a. Each heavy (armored) brigade is equipped with 58 Abrams tanks, 120 Bradley fighting vehicles, 120 M113-based vehicles, and 16 M109 

self-propelled howitzers.

b. Additional M113-based vehicles would be needed to equip division headquarters, fire brigades, and manueuver enhancement brigades. 

Additional M109 self-propelled howitzers would be needed to equip fire brigades.

c. Sets of equipment sufficient for five brigade combat teams (BCTs) are prepositioned in various locations around the world to allow quick 

deployment of units. (BCTs, which the Army puts together for specific operations, are currently being replaced by modular heavy units. In 

2003, they included between 3,000 and 5,000 soldiers and roughly 300 armored vehicles.)

d. Represents vehicles needed at various locations for training soldiers in their use and maintenance and for replacing vehicles that are 

removed from units for repairs or upgrades or that are lost in accidents or in combat. 

heavy brigade.4 But unlike the premodular combat brigades, modular heavy brigades will have support units 

permanently assigned to them—which the Army argues 

will make modular brigades better able to operate independently. Moreover, under the modular structure, brigade combat teams will not have to be put together on an 

ad hoc basis when they are required for operations because team members will be permanently organized into 

a modular brigade.

Equipping Modular Units

The Army will need fewer armored vehicles to equip and 

support units under its modular structure than it required 

for premodular units in 2003. Because modular combat 

brigades are designed to be self-contained, standardized 

units, they will comprise more support forces and fewer 

combat forces—and thus more trucks and fewer armored 

Heavy Brigadesa

Active component (19 brigades) 1,100 2,300 2,300 300

National Guard (Eight brigades) 450 950 950 150 _____ _____ _____ ____

Subtotal 1,550 3,250 3,250 450

Other Unitsb 0 0 2,300 200

Prepositionedc 300 600 600 100

Operational Readiness Float and Training Based 400 650 650 150 _____ _____ _____ _____

Total 2,250 4,500 6,800 900

Memorandum:

Total Vehicles Required for the Premodular Army

in 2003 4,650 5,650 11,650 1,350

Total Vehicles in Inventory as of 2005 5,850 6,650 13,700 1,500

Abrams Tanks

Bradley Fighting 

Vehicles

M113-Based 

Vehicles

M109 Self-Propelled 

Howitzers

4. A premodular combat battalion (such as an infantry or tank battalion) includes 600 to 800 soldiers.
CHAPTER TWO DESCRIPTION OF THE ARMY’S MODULARITY INITIATIVE AND FUTURE COMBAT SYSTEMS PROGRAM 21

vehicles—compared with a premodular mechanized infantry or armored brigade combat team (see Table 2-2 on 

page 19). That factor, plus the smaller number of heavy 

combat brigades in the Army in 2011, when the reorganization is complete, will yield a smaller requirement for armored vehicles in 2011 than in 2003 (see Table 2-3). 

That reduction could allow the Army to both retire some 

of its oldest armored vehicles, as it converts units to the 

modular design, and modernize heavy units that remain 

in the National Guard.

The Future Combat Systems Program

Although the Army’s modularity initiative is designed to 

make its combat forces more flexible and responsive, the 

initiative will not enable them to deploy more quickly to 

remote trouble spots. The equipment proposed for a 

heavy modular brigade will weigh as much as the equipment associated with a typically equipped premodular armored or mechanized infantry brigade combat team. 

Therefore, transporting a modular heavy brigade will require the same amount and types of equipment as are 

needed to move a typical premodular heavy brigade combat team.

To address the obstacles to rapid deployment, the Army 

initiated the FCS program, which it regards as the cornerstone of its efforts to transform itself into the kind of 

force that the military needs in today’s national security 

environment. The program, as the Army envisions it, 

would develop the next generation of combat vehicles to 

be as lethal and survivable as current weapons but to 

weigh much less and require far less fuel and other logistics support. The program would develop eight new 

manned armored vehicles as well as four classes of unmanned aerial vehicles, three types of unmanned ground 

vehicles, unattended ground sensors, a missile launcher, 

and a new munitions system, all of which would be 

linked by an advanced communications network into an 

integrated combat system of systems.

Manned FCS Vehicles

The eight types of manned FCS vehicles that the Army 

plans to develop are intended to replace the armored 

vehicles that currently equip its heavy combat units. 

(The design of those existing vehicles, as described in 

Chapter 1, dates from before 1980; moreover, especially 

in the case of the Abrams tank, the vehicles are very heavy 

and difficult to transport.) The missions and configurations of the eight new FCS vehicles would differ, but they 

would share a common chassis, engine, and other components and be much lighter and more fuel efficient than 

the armored vehicles in the Army’s current fleet. The service argues that the common design will reduce the logistics burden—in terms of spare and replacement parts and 

required tools—associated with maintaining the eight 

different vehicles and that the FCS vehicles’ greater fuel 

efficiency (relative to existing armored vehicles) should 

lessen the amount of refueling required on the battlefield.

The initial goal of the FCS program was to develop vehicles that could be transported by the Air Force’s large fleet 

of C-130 aircraft, which would require that a vehicle 

weigh less than 20 tons. Although that may still be the 

program’s ultimate goal, recent Army documents suggest 

that the weight limit for the initial design of the manned 

FCS ground vehicles has been relaxed and set at 24 tons.5

Whether the ultimate weight of the vehicle will be 

24 tons is an open question, but to meet even that goal, 

FCS vehicles would not be able to rely on heavy armor 

for protection. (The Army’s existing armored vehicles, 

which are equipped with heavy armor, weigh far more 

than 24 tons: the latest models of the Abrams tank weigh 

70 tons or more, and those of the Bradley fighting vehicle 

and M109 self-propelled howitzer weigh more than 30 

tons.) Instead, to help them survive, FCS vehicles as envisioned by the Army would rely on knowledge of the enemy’s whereabouts to avoid attacks and on active systems 

of protection that could detect and neutralize incoming 

projectiles.

The manned vehicles to be developed under the FCS program include seven variants that will replace all types of 

armored vehicles now in the Army’s heavy units and one 

variant that has no current counterpart fielded in the 

Army’s brigades (see Figure 2-1 and Table 2-4). The following descriptions of the various FCS vehicles are based 

on the Army’s designs and requirements for the vehicles 

in early 2006.

5. See Office of the Secretary of Defense, Future Combat Systems: 

Selected Acquisition Report (September 30, 2005).
22 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Figure 2-1.

Manned FCS Vehicles

Source: Congressional Budget Office based on a presentation by 

Brigadier General Charles Cartwright and Dennis Muilenburg to the Science and Technology Panel of the Association of the United States Army, “One Team—Equipping 

Our Joint Warfighters with the World’s Best Capability” 

(Williamsburg, Va., February 11, 2005).

Note: FCS = Future Combat Systems; NLOS = non-line-of-sight.

B The mounted combat system (MCS) would replace 

the Abrams tank. Equipped with a new 120-millimeter gun capable of destroying targets at a distance of 

up to 8 kilometers, the MCS would weigh one-third 

as much as the latest model of the Abrams tank. Despite having one-fifth as much fuel-storage capacity as 

the Abrams, the MCS’s cruising range, based on current designs, would be about two-thirds that of the 

tank (300 km as opposed to 440 km), and its maximum speed on roads (80 km per hour) would be 

about 20 percent greater.

B The infantry carrier vehicle (ICV) is being designed to 

carry up to nine soldiers and two crew members and 

would replace some Bradley fighting vehicles and 

M113 armored personnel carriers in the current fleet. 

Compared with the Bradley, the ICV would be about 

25 percent lighter, could cruise 70 percent as far on a 

tank of fuel that would be 40 percent smaller, and be 

capable of speeds almost 30 percent greater on roads. 

The ICV’s cannon, at 30 mm, would be slightly larger 

and more powerful than the Bradley’s 25 mm gun. 

Compared with the M113-based personnel carriers, 

the ICV would be roughly twice as heavy and have less 

than two-thirds of the cruising range but be able to 

travel at a higher speed. Since it would be equipped 

with a 30-mm cannon, however, the ICV would have 

greater firepower than the current M113-based vehicle, which is armed only with a machine gun.

B As currently designed, the non-line-of-sight mortar 

(NLOS-M) would fire precision-guided mortar 

rounds and be able to operate 24 hours a day in all 

types of weather. Compared with the current M113-

based mortar carrier that it would replace, the 

NLOS-M would be equipped with an improved machine gun and could travel 20 percent faster on roads. 

However, its cruising range would be roughly 60 percent less. 

B The non-line-of-sight cannon (NLOS-C) is designed 

to provide long-range fire to support combat battalions. It would replace the M109 self-propelled howitzers in combat brigades and, on the basis of current 

designs, would be capable of 50 percent faster rates of 

fire. The NLOS-C could travel 25 percent faster on 

roads, but its cruising range would be roughly the 

same as that of the M109 howitzer.

B According to its current design, the reconnaissance 

and surveillance vehicle will feature a suite of advanced sensors to locate and identify enemy targets in 

all weather conditions, day or night. Like the ICV, it 

would be capable of slightly higher speeds than the 

Bradley fighting vehicle, but its range and fuel storage 

capacity would be about the same.

B The command-and-control vehicle would provide 

commanders with the information and communications capability needed to command and control their 

subordinate forces while on the move. Compared with 

the M113-based command-and-control vehicle it 

would replace, the FCS vehicle would be able to travel 

at higher speeds and would carry an improved 25-mm 

machine gun.

Reconnaissance and Surveillance Command and Control

NLOS Mortar NLOS Cannon

Mounted Combat System Infantry Carrier

Medical Recovery and Maintenance
CHAPTER TWO DESCRIPTION OF THE ARMY’S MODULARITY INITIATIVE AND FUTURE COMBAT SYSTEMS PROGRAM 23

Table 2-4.

FCS Replacements for Armored Vehicles in the Army’s Modular Heavy Combat 

Brigades

Source: Congressional Budget Office based on Office of the Secretary of Defense, Future Combat Systems: Selected Acquisition Report

(December 31, 2005); and data from the Department of the Army.

Note: FCS = Future Combat Systems; n.a. = not applicable.

B The FCS medical vehicle (MedV), which is designed 

to provide advanced life support to critically injured 

soldiers while they are being evacuated from the battlefield, has no existing counterpart that has been 

fielded in large numbers with combat brigades. By 

comparison with the M113-based battlefield ambulance that is currently in the Army’s inventory, the 

FCS MedV would provide greater capability to treat 

the wounded as they are being evacuated.

B The FCS recovery and maintenance vehicle is being 

designed to transport repair crews around the battlefield and to recover disabled vehicles. Weighing 

60 percent less than the M88 recovery vehicle it would 

replace in the Army’s combat units, the FCS vehicle 

would have a cruising range roughly equal to that of 

the latest model of the M88 but a fuel tank onequarter the size of that vehicle’s.

Unmanned Aerial and Ground Vehicles

The FCS program would develop four classes of unmanned aerial vehicles (UAVs) to carry out surveillance, 

identify targets, and relay communications to the units 

that the UAVs support. According to the Army’s current 

designs, the four classes, depending on the tasks they are 

slated to perform, would vary by range and the length of 

time they could remain in the air (see Figure 2-2).

B Class I UAVs would provide information to the individual soldier. The Army’s current descriptions specify 

that it weigh less than 15 pounds, be able to take off 

and land vertically, have a range of 8 km, and be able 

to stay aloft for almost an hour.

B Like Class I UAVs, Class II vehicles would also be capable of taking off and landing vertically but would 

have twice the range and endurance of the smaller 

UAVs. Class II UAVs, which would support commanders of infantry or MCS vehicle companies, 

are expected to weigh between 100 pounds and 

150 pounds.

B Class III UAVs are scheduled to replace the Shadow 

UAV that some Army units currently use and would 

provide information to battalion commanders. Current designs call for an aircraft that weighs 300 pounds 

to 500 pounds, has a range of 40 km, and is capable of 

staying aloft for six hours. Compared with the Shadow 

UAV, Class III UAVs could remain airborne longer 

and carry heavier payloads with more and better sensors, enabling them to find and identify more targets 

at greater distances.

Vehicle Mission Name Name

Combat Abrams tank 58 Mounted combat system 60

Infantry Carrier Bradley fighting vehicle 80 Infantry carrier vehicle 102

M113-based vehicle 53 n.a. n.a.

Mortar Carrier M113-based vehicle 14 Non-line-of-sight mortar 24

Artillery M109 self-propelled howitzer 16 Non-line-of-sight cannon 18

Scouting Bradley fighting vehicle 40 Reconnaissance and surveillance vehicle 30

Command and Control M113-based vehicle 44 Command-and-control vehicle 49

Medical n.a. n.a. Medical vehicle 29

Recovery M88 recovery vehicle 27 Recovery and maintenance vehicle 10 ____ ____

Total 332 322

Vehicles in the Current Fleet Manned FCS Vehicles

Number Number
24 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Figure 2-2.

Unmanned FCS Aerial Vehicles

Source: Congressional Budget Office based on a presentation by 

Brigadier General Charles Cartwright and Dennis Muilenburg to the Science and Technology Panel of the Association of the United States Army, “One Team—Equipping 

Our Joint Warfighters with the World’s Best Capability” 

(Williamsburg, Va., February 11, 2005).

Note: FCS = Future Combat Systems.

B Class IV UAVs, which are designed to support brigade 

commanders, would be produced in two versions. 

One would be capable of operating in tandem with 

Army helicopters; the other would be able to relay 

communications for as long as 24 hours and provide 

reconnaissance, early warning, and surveillance from a 

distance of as much as 75 km. Class IV UAVs could 

weigh more than 3,000 pounds and be as long as 

23 feet.

Three types of unmanned ground vehicles, or robots, 

would also be developed under the FCS program (see 

Figure 2-3). In general, those vehicles are designed to 

lighten the loads of individual soldiers by performing 

continuous surveillance, carrying supplies, or entering 

areas of high risk.

B The Army is developing two types of large armed robotic vehicles (ARVs), the initial versions of which are 

expected to weigh slightly more than 13 tons. Plans 

are for the assault variant (ARV-A) to provide remote 

reconnaissance and armed cover for soldiers and to deploy sensors and weapons in bunkers, buildings, and 

caves. According to the Army’s current designs, the reconnaissance, surveillance, and target acquisition variant of the ARV would carry additional sensors and 

communications equipment and provide remote reconnaissance of urban terrain and other dangerous 

locales.

B Current designs call for the multifunctional utility, logistics, and equipment (MULE) vehicle—a 2.5-ton 

robot—to be built in three variants: the transport version, which would carry from 1,900 pounds to 2,400 

pounds of soldiers’ equipment; the countermine 

MULE, which would detect, mark, and defuse mines; 

and the ARV-assault-light, which would be a smaller, 

lighter version of the ARV-A.

B The small unmanned ground vehicle (SUGV) is a robot designed to weigh less than 30 pounds and be carried by a soldier. The SUGV would carry as much as 

six pounds of equipment (typically, electronic sensors) 

for use in investigating caves, tunnels, buildings, or 

other potentially dangerous places. Early versions of 

this system are currently being used by soldiers in Iraq.

Unattended Sensors, the Launcher, Intelligent 

Munitions, and the Network

The remaining hardware systems in the FCS program are 

the unattended ground sensors, a missile launcher, and 

the intelligent munitions system (see Figure 2-4).

B The unattended ground sensors—small modules 

equipped with relatively low-cost, expendable, multimodal sensors—are designed to detect intruders, 

chemicals, and biological agents and conduct surveillance in remote locations.

B The non-line-of-sight launch system—a launch container equipped with 15 advanced missiles—is designed to be easily deployed and to be operated 

remotely or set for automated operations.

B Plans for the intelligent munitions system (IMS) show 

it to be a system of sophisticated land mines equipped 

with sensors and communications links that would 

enable it to transmit information about personnel or 

vehicles whose presence it had detected. The mines 

could be turned on or off remotely and, to ensure that 

individual IMS units did not become residual hazards, 

would be designed to self-destruct on command or 

after a preset interval.

Class I Class II

Class III Class IV
CHAPTER TWO DESCRIPTION OF THE ARMY’S MODULARITY INITIATIVE AND FUTURE COMBAT SYSTEMS PROGRAM 25

Figure 2-3.

Unmanned FCS Ground Vehicles

Source: Congressional Budget Office based on a presentation by 

Brigadier General Charles Cartwright and Dennis Muilenburg to the Science and Technology Panel of the Association of the United States Army, “One Team—Equipping 

Our Joint Warfighters with the World’s Best Capability” 

(Williamsburg, Va., February 11, 2005).

Note: FCS = Future Combat Systems; ARV = armed robotic vehicle; MULE =multifunctional utility, logistics, and equipment; 

RSTA =reconnaissance, surveillance, and target acquisition.

The final but perhaps most important component of the 

FCS program is the network that, according to the Army, 

would “[allow] the FCS . . . to operate as a cohesive system of systems where the whole of its capabilities is 

greater than the sum of the parts.”6 The network would 

encompass the common operating software by which all 

FCS components would communicate with each other 

and share data; the communications and computer systems that would provide secure, reliable access to information over extended distances and complex terrain; and 

intelligence and surveillance sensors that would allow 

weapon systems in an FCS-equipped brigade to avoid enemy fire, maintain contact with each other, and destroy 

adversaries at long range.

Schedule for Fielding FCS Components

Despite the wide diversity that characterizes the 18 individual systems of the FCS program, the Army initially 

planned to develop and field all of them in concert—a 

goal that the service has had to scale back to some extent, 

although the current schedule is still quite tight. The ambitiousness and complexity of the program have caused 

several changes in plans since it was first conceived. As 

described by then Army Chief of Staff General Eric Shinseki early in 2000 and laid out in an FCS program briefing in November 2002, the program would have included a short (three-year) system development and 

demonstration (SDD) phase starting in the spring of 

2003.7

 All 18 systems were to enter production by 2006 

and start initial fielding in 2008;8

 an ambitious procurement program would then follow, with annual purchases 

of three brigades’ worth of all 18 FCS components. At 

that rate, General Shinseki predicted, all of the Army’s 

combat brigades could be equipped with FCS components by 2032.

As the program approached the beginning of the SDD 

phase and a major review by the Office of the Secretary of 

Defense, the difficulty of meeting the schedule laid out 

by General Shinseki became apparent. The Army extended the SDD phase by almost two years and delayed 

until the second quarter of 2008 the decision about 

whether or not to begin production.9

 It also pushed back 

to 2011 the initial fielding of the 18 FCS components—

or initial operating capability (IOC)—and reduced the 

rate of procurement to two brigades’ worth of components per year rather than the three brigades’ worth initially projected. At that rate, equipping the first 15 bri6. U.S. Army Unit of Action Program Manager, Future Combat Systems (FCS); 18+1+1 Systems Overview, version 18 (September 15, 

2005), p. 4.

ARV-Assault ARV-RSTA

MULE Transport Version MULE Countermine Version

ARV-Assault (Light)

Small Unmanned

Ground Vehicle

7. The SDD phase, as defined in this analysis, would extend from 

Milestone B (the terminology used in the Defense Department’s 

acquisition programs to mark the program’s entrance into the 

SDD phase) to Milestone C for manned vehicles—at which point 

approval to enter production would be granted by the Office of 

the Secretary of Defense.

8. Briefing by the Army’s Future Combat Systems Team’s Program 

Review Board (November 12, 2002).

9. Government Accountability Office, Issues Facing the Army’s Future 

Combat Systems Program, GAO-03-1010R (August 2003).
26 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Figure 2-4.

Other Unmanned FCS Systems

Source: Congressional Budget Office based on a presentation by 

Brigadier General Charles Cartwright and Dennis Muilenburg to the Science and Technology Panel of the Association of the United States Army, “One Team—Equipping 

Our Joint Warfighters with the World’s Best Capability” 

(Williamsburg, Va., February 11, 2005).

Note: FCS = Future Combat Systems; NLOS = non-line-of-sight.

gades with FCS components would be delayed from 

2015 (the original schedule) to 2020.

The program emerged from the review necessary to enter 

the SDD phase, in the spring of 2003, with additional 

changes. The time to be devoted to system development 

and demonstration was again extended, and a decision 

about whether to start production was delayed until November 2008.10 The Army, reflecting concerns about the 

affordability of developing, testing, and producing all 18 

FCS components on the tight schedule in place at the 

program’s entrance into the SDD phase, planned initially 

to introduce 14 of the 18 systems in 2011, with the understanding that the remaining four—the recovery and 

maintenance vehicle, two classes of UAVs, and the armed 

robotic vehicles—would be introduced later. Otherwise, 

the procurement and fielding schedule remained the 

same.

A restructuring of the program in July 2004 resulted in 

yet another schedule.11 The Army introduced a new concept for the program that extended the SDD phase by almost four years and took into account (to some extent) 

the different levels of technical readiness of the various 

systems by introducing them in four phases—the Army 

called them spirals, or spin-outs—as the systems were 

proven. The plan as described in July 2004 was to first introduce parts of the network and three other systems—

the unattended ground sensors, the intelligent munitions 

system, and the non-line-of-sight launch system—into 

one experimental unit for testing in 2008. If those tests 

proved successful, the three FCS components and the rudimentary network would be introduced into additional 

units. Two years later, in a second spiral, the Army would 

introduce a preliminary version of the Class III UAV, a 

prototype of the non-line-of-sight cannon, and additional 

portions of the network, first into the experimental unit 

and subsequently into other units. In 2012, it would introduce unmanned ground vehicles and in 2014, the remaining three classes of UAVs and final versions of all 

eight manned vehicles. In that way, the least technologically challenging components of the program would be 

introduced earlier, and the systems that were more difficult to develop could be deferred until later.

That approach pushed the fielding of the first brigade 

equipped with all 18 FCS components to 2015. After 

that, the Army planned to equip its combat brigades with 

the full complement of systems at a maximum rate of two 

brigades per year, as outlined in the Selected Acquisition

10. Statement of Paul L. Francis, Director, Acquisition and Sourcing 

Management, Government Accountability Office, before the Subcommittee on Tactical Air and Land Forces, Committee on 

Armed Services, House of Representatives, published as Government Accountability Office, Defense Acquisitions: The Army’s 

Future Combat Systems’ Features, Risks, and Alternatives, GAO-04-

635T (April 1, 2004).

NLOS Launch System

Unattended Ground Sensors

Intelligent Munitions

System

11. Statement of Paul L. Francis, Director, Acquisition and Sourcing 

Management, Government Accountability Office, before the Subcommittee on AirLand of the Senate Committee on Armed Services, published as Government Accountability Office, Defense 

Acquisitions: Future Combat Systems—Challenges and Prospects for 

Success, GAO-05-442T (March 16, 2005); and Andrew Feickert, 

The Army’s Future Combat System (FCS): Background and Issues for 

Congress, CRS Report for Congress RL32888 (Congressional 

Research Service, April 28, 2005; updated May 5, 2006).
CHAPTER TWO DESCRIPTION OF THE ARMY’S MODULARITY INITIATIVE AND FUTURE COMBAT SYSTEMS PROGRAM 27

Figure 2-5.

Disposition of the Army’s Heavy Brigades Under the Administration’s 

Plan 

(Number of brigades)

Source: Congressional Budget Office based on data from the Department of the Army and a private briefing by the Army titled “The Army 

Modular Force, 2004-2020” (July 2005).

Note: “Premodular” and “modular” refer to the Army’s ongoing modularity initiative, which seeks to make the service more flexible by 

changing its structure from one based on 18 divisions, several of unique design, to one based on 70 combat brigades, each one of only 

three designs. “Heavy” units are those equipped with tracked armored vehicles.

Report (SAR) submitted to the Congress in December 

2004.12 Nine months later, the September 2005 SAR 

showed that the schedule had changed once again, and 

the Army’s planned maximum rate for procuring FCS 

components had dropped to 1.5 brigades’ worth per year. 

At that rate, the Army would have only six FCS-equipped 

brigades in the field in 2020, and it would be 2026 before 

it fielded 15 such brigades (see Figure 2-5). Looking forward, if the Army continued to buy enough FCS components to equip 1.5 brigades per year, it would take until 

2034 to equip all 27 of the Army’s heavy brigades with 

the new systems—a very different outcome from that 

originally envisioned by General Shinseki in early 

2000.13

2003 2005 2007 2009 2011 2013 2015 2017 2019 2021 2023 2025

0

5

10

15

20

25

30

35

40

45

Premodular

Premodular

Modular

Modular

Future Combat Systems

Active-Component Units

National Guard Units

12. The Department of Defense (DoD) provides Selected Acquisition 

Reports containing the department’s projections of development 

schedules, purchase rates and quantities, and costs through the 

duration of a program. DoD is required by the Congress to provide SARs for major programs that meet certain guidelines.

13. An additional three years would be needed to equip five sets of 

prepositioned equipment with FCS components.

CHAPTER

3

Potential Effects of and Concerns 

About the Army’s Modernization Plans

The Army’s modularity initiative and the Future 

Combat Systems program could significantly transform 

the service, but a substantial investment is required to 

carry them out. This chapter examines how the two initiatives and the Army’s continuing efforts to upgrade its armored vehicle fleet affect the service’s costs, its ability to 

deploy units quickly, and the age and size of its armored 

combat vehicle fleet. The chapter also examines some of 

the questions and concerns that have been raised about 

the viability and feasibility of the FCS program.

How Modernization Plans Would Affect 

the Army’s Budget

The FCS program is by far the most expensive modernization effort planned by the Army over the next 20 years. 

Based on the service’s estimates in the Selected Acquisition Reports for the program issued in September and 

December 2005, the total cost from 2007 to 2025 to develop and procure the first 15 brigades’ worth of FCS 

equipment would be $122 billion (in 2006 dollars). In 

contrast, the cost from 2007 through 2011 to convert all 

of the Army’s combat brigades to a modular structure has 

been pegged at $54 billion. The Army has also budgeted 

several billion dollars for major upgrades to its armored 

vehicles during the next decade.

Cost of the FCS Program

The FCS program will require significant investment by 

the Army during the next 20 years. The research and development (R&D) portion of the program is scheduled 

to extend through 2016; according to the Army’s current 

estimates, it will require annual funding exceeding $1 billion from 2007 through 2013 and topping $3 billion 

from 2007 through 2009. At those levels, R&D funding 

for the FCS program would represent more than onethird of the Army’s total annual R&D budget for the five 

years from 2007 through 2011. All told, the planned 

R&D investment in FCS components would require 

$21 billion during the 2007-2016 period.1

On the basis of information in recent SARs, the Congressional Budget Office estimates that the total cost for procuring the first 15 brigades’ worth of FCS components 

will be about $100 billion and the average unit procurement cost will be $6.7 billion per brigade. Each FCSequipped brigade would include roughly 300 manned vehicles, more than 230 unmanned ground vehicles, 

112 unmanned aerial vehicle systems, and numerous additional unattended ground sensors, non-line-of-sight 

launch systems, and munitions (see Table 3-1 for details). 

Under the Army’s current plan to purchase 1.5 brigades’ 

worth of FCS components annually beginning in 2015, 

the FCS program would require $10 billion in that year 

and $8 billion to $10 billion annually thereafter—that is, 

for as long as the program continued purchases at that 

rate (see Figure 3-1).

Under that plan, the total funding required for the FCS 

program from 2007 through 2025 would be $140 billion, in CBO’s estimation. That amount would include 

$21 billion for R&D and $119 billion to procure 18 brigades’ worth of FCS equipment—enough to equip all 

but one of the heavy modular brigades planned for the 

Army’s active component. Although the December 2005 

SAR outlined funding for only 15 brigades’ worth of 

equipment, the Army’s intention at the inception of the 

FCS program in 2000 and as described in its 2002 modernization plan was to equip all of its combat brigades 

similarly. That goal would require purchasing 70 brigades’ worth of FCS equipment, which at the rate of

1. Those estimates are based on the program described in the 

December 2005 SAR.
30 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Table 3-1.

Planned New Components for an 

FCS-Equipped Brigade 

Source: Congressional Budget Office based on Office of the Secretary of Defense, Future Combat Systems: Selected Acquisition Report (December 31, 2005).

Note: FCS = Future Combat Systems.

a. Does not include equipment for training or for replacing vehicles 

that are removed from units for repairs or upgrades or that are 

lost in accidents or in combat.

b. The Army has not yet determined whether each brigade will 

have 30 or 88 intelligent munitions systems.

1.5 brigades’ worth per year could take until 2060. Even 

if the Army abandoned that goal and equipped only its 

heavy units (27 brigades) with FCS components, the program would extend its purchases until 2031 and have a 

total acquisition cost (R&D plus procurement), starting 

in 2007, of almost $190 billion.

Cost of the Modularity Initiative

Because the Army’s new modular units are designed to be 

equipped and staffed differently from the units they are 

scheduled to replace, the Army will have to purchase 

equipment and build facilities to carry out the reorganization of its forces. The total cost of the restructuring, 

based on the Army’s estimates, would be $54 billion from 

2007 through 2011 (see Table 3-2). The greatest share of 

that amount ($29 billion) would cover equipment for the 

new units, including either newly purchased or refurbished Abrams tanks, Bradley fighting vehicles, trucks 

and other support equipment, and large numbers of radios and other communications gear (see Table 3-3 on 

page 33).2

 Moreover, the Army might require as many as 

30,000 additional personnel (at a cost of $16 billion), although the service has stated that they will be needed 

only through 2011. The remaining costs are associated 

with building new brigade facilities (for example, headquarters buildings and maintenance sheds) as new units 

are created or existing ones moved to new bases, and purchasing supplies for sustainment and training (for example, fuel, ammunition for training, and other expendable 

goods).

Cost of Planned Upgrades to Armored 

Combat Vehicles

The Administration’s plan for upgrading vehicles in the 

Army’s current fleet, as described in documents submitted with the President’s budget for 2007, would require 

roughly $6 billion during the years 2007 to 2016.3

 Those 

funds would pay to modernize almost 90 Abrams tanks, 

bringing them to the A2 SEP (System Enhancement ProMounted Combat System 60

Infantry Carrier Vehicle 102

Command-and-Control Vehicle 49

Reconnaissance and Surveillance Vehicle 30

Non-Line-of-Sight Mortar 24

Non-Line-of-Sight Cannon 18

Medical Vehicle 29

Recovery and Maintenance Vehicle 10

Armed Robotic Vehicle-Assault 18

Armed Robotic Vehicle-Reconnaissance,

Surveillance, and Target Acquisition 27

Armed Robotic Vehicle-Assault (Light) 18

Multifunctional Utility, Logistics, and

Equipment Vehicle 90

Small Unmanned Ground Vehicle 81

Class I 54/108

Class II 36/36

Class III 12/48

Class IVa 2/8

Class IVb 8/16

Unattended Ground Sensors 136

Non-Line-of-Sight Launch System 60

Intelligent Munitions System 30 or 88b

Manned Systems

Unmanned Ground Vehicles

Unmanned Aerial Vehicles 

(Launch and Control Units/Aircraft)

Quantitya

Other

2. The estimate of procurement costs for the Army’s modularity initiative includes funds requested in the President’s 2007 budget for 

upgrading the Army’s tanks, Bradley fighting vehicles, and M113-

based vehicles.

3. Plans through 2016 for upgrading Bradley fighting vehicles are 

described in the SAR for Bradley upgrades dated December 31, 

2005; plans for the Abrams tanks and M113-based vehicles are 

available only through 2011. CBO’s analysis covers only funds for 

major upgrades as requested in the procurement account of the 

Army’s budget and does not include funds provided or requested 

in the operation and maintenance account. Those latter funds are 

generally used to support day-to-day maintenance and not efforts 

to modernize the armored combat vehicle fleet.
CHAPTER THREE POTENTIAL EFFECTS OF AND CONCERNS ABOUT THE ARMY’S MODERNIZATION PLANS 31

Figure 3-1.

Projected Total Annual Investment in 

the Future Combat Systems Program

(Billions of 2006 dollars)

Source: Congressional Budget Office based on Office of the Secretary of Defense, Future Combat Systems: Selected Acquisition Reports (September 30 and December 31, 2005).

a. Incorporates the assumption that the Army will continue to purchase 1.5 brigades’ worth of FCS equipment indefinitely.

gram) configuration; roughly 1,600 Bradley fighting vehicles, upgrading them to the A2 ODS (Operation 

Desert Storm) or A3 model; and more than 840 M113-

based vehicles, converting them to the A3 variant (see 

Table 3-4 on page 34). (The Army’s budget does not include funds for any major upgrades to the M109 selfpropelled howitzers.)

Many details of the Army’s plans after 2011 are not yet 

available, but some briefings indicate that additional upgrades to its armored vehicles will incorporate technologies from the FCS program. Whether or not that occurs, 

the Army must continue to invest funds in its existing vehicles for many years if it is to keep them in good condition and up to date technologically. During the early part 

of this decade, the Army reportedly was reluctant to make 

such an investment because it was planning to replace all 

of its armored vehicles with FCS vehicles on an accelerated schedule. Now that the FCS schedule has been extended and the total number of brigades’ worth of equipment has been reduced, that rationale for a lower level of 

investment no longer exists.

How Modernization Plans Would

Affect the Army’s Ability to Deploy 

Units Quickly

Although the Army’s modularity initiative and the FCS 

program could help reduce the amount of heavy equipment in brigade-sized units, neither would significantly 

improve the speed at which those units could be deployed. The reason is that moving a modular heavy brigade, whether equipped with existing systems or FCS 

components, involves transporting more than 1,000 vehicles, including more than 300 tracked vehicles (primarily 

armored combat vehicles) and more than 500 trucks (see 

Table 3-5 on page 35). To be transported by air, an FCSequipped brigade would require 340 to 370 C-17 sorties; 

if the destination was, for example, Djibouti, the process 

would take 18 to 20 days (see Table 3-6 on page 36).4 A 

modular heavy brigade equipped with existing systems 

would require 420 sorties to deploy by air to Djibouti. 

Thus, replacing the tracked armored combat vehicles in 

the Army’s current fleet with manned FCS vehicles would 

yield at most a 19 percent reduction in the airlift sorties 

(and time) needed to deploy a heavy unit overseas.

Brigade-sized units are rarely deployed alone, so it is useful to examine the time needed to deploy larger formations, such as divisions. Premodular divisions (described in 

Chapter 1) typically included three brigade combat teams 

and came in several types. In most cases, the equipment 

for a premodular heavy division totaled almost 100,000 

tons, and although it required several sealift ships for 

transport, it could be moved by the Military Sealift 

Command’s fleet in one sailing. Thus, a premodular 

heavy division that comprised three brigade combat 

teams could take roughly 110 days to deploy to Djibouti 

by air but could be sealifted there in less than 30 days (see 

Table 3-6 on page 36). 

2005 2010 2015 2020 2025

0

2

4

6

8

10

12

Research,

Development,

Testing,

and Evaluation

Procurementa

4. That estimate is based on an average load of 50 tons to 55 tons per 

C-17, which would limit the number of manned FCS vehicles per 

sortie to two. The Army argues that it may be possible to load 

three manned FCS vehicles on a single C-17 aircraft. If that could 

be done, transporting an FCS brigade could require as many as 

54 fewer C-17 sorties—and two to three fewer days—to transport 

it to Djibouti by air. Since the vehicles have not yet been built, 

however, it is not possible to determine how many would fit into a 

C-17. Furthermore, three FCS vehicles, each weighing 24 tons or 

more, would exceed a C-17’s maximum allowable cabin load of 65 

tons for a “leg” of 3,200 nautical miles.
32 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Table 3-2.

Total Costs for the Army’s Modularity Initiative

(Billions of 2006 dollars)

Source: Congressional Budget Office based on Government Accountability Office, Force Structure: Actions Needed to Improve Estimates 

and Oversight of Costs for Transforming Army to a Modular Force, GAO-05-926 (September 2005), p. 10.

Note: The Army’s ongoing modularity initiative seeks to make the service more flexible by changing its structure from one based on 18 divisions, several of unique design, to one based on 70 combat brigades, each one of only three designs.

a. Primarily, costs to purchase supplies, such as fuel, ammunition for training, and other expendable goods.

Although composed of smaller and generally lighter 

units, modular divisions comprise four combat brigades 

rather than three and may ultimately weigh more than 

their premodular counterparts. A modular heavy division 

with four modular heavy brigades could have almost 

120,000 tons of equipment, or roughly 20 percent more 

than the amount assigned to a premodular heavy division—and that extra weight could significantly affect the 

time required to deploy the division by air. However, the 

additional equipment would not increase the time needed 

to deploy the division by sea because the additional 

20,000 tons could be easily accommodated by the MSC’s 

sealift fleet (see Table 3-6 on page 36).

An FCS-equipped division, according to the Army’s current design, would be composed of four FCS-equipped 

brigades and weigh roughly 20 percent less than a modular heavy division.5

 Even so, transporting an FCSequipped division by air to Djibouti would take at least 

115 days. Moreover, it is unlikely that such a division 

could be transported by sea solely by the MSC’s fleet of 

fast sealift ships. As a consequence, to deploy a division 

equipped with four FCS brigades to Djibouti by sea 

could take just as long as to deploy an entire modular 

heavy division to that location (see Table 3-6 on 

page 36).

How the Administration’s Plan Would 

Affect the Army’s Armored Combat 

Vehicle Fleet

Because the Army is not scheduled to begin to introduce 

manned FCS vehicles into its units until 2015 and then 

plans to continue to equip the units with the new systems 

at a relatively slow pace, the service is expected to retain 

many of the armored combat vehicles in its current fleet 

for at least 20 more years. The modularity initiative may 

allow the Army to reduce the size of the fleet and retire 

some of its oldest vehicles (see Chapter 2), but those remaining will have to be maintained in a serviceable condition for some time. In CBO’s estimation, the effect of 

the upgrades that the Army plans to undertake between 

2007 and 2016 will be small.

Effect of Planned Upgrades

The more than 2,500 upgrades that the Army plans to 

procure from 2007 through 2016 would improve the capabilities of its tanks, fighting vehicles, and personnel carriers and slightly lessen the increase in the average age of 

the armored vehicle fleet that would otherwise occur over 

that period. When combined with the additional upgrades funded in the supplemental appropriation enacted 

this past June, the planned upgrades would further the 

Army’s efforts toward meeting its goal of having enough 

of the latest models of its Abrams tanks and Bradley 

fighting vehicles to equip all of its heavy brigades and 

prepositioned stocks. The planned upgrades, however, 

would result in an average age for the roughly 28,000 armored vehicles in the fleet (21 years in 2016) that was 

Equipment 5.3 5.7 6.1 6.2 5.4 28.6

Personnel 3.1 3.2 3.2 3.2 3.2 15.9

Facilities 0.5 0.5 1.4 1.4 1.4 5.1

Sustainment and Traininga 0.7 1.1 1.0 0.9 0.8 4.5 ___ ____ ____ ____ ____ ____

Total 9.6 10.4 11.7 11.6 10.8 54.1

Total,

2007 2008 2009 2010 2011 2007 to 2011

5. That estimate incorporates the assumption that units in the division other than combat brigades would be similarly equipped, 

regardless of the types of combat brigades that the division 

included.
CHAPTER THREE POTENTIAL EFFECTS OF AND CONCERNS ABOUT THE ARMY’S MODERNIZATION PLANS 33

Table 3-3.

Selected Items That the Army Plans to 

Buy to Implement Its Modularity 

Initiative

Source: Congressional Budget Office based on Department of the 

Army, The Army Modular Force and Future Combat Systems Strategy, version 1.2 (undated).

Notes: The Army’s ongoing modularity initiative seeks to make the 

service more flexible by changing its structure from one 

based on 18 divisions, several of unique design, to one 

based on 70 combat brigades, each one of only three 

designs.

FBCB2 = Future Battle Command Brigade and Below.

a. Purchases are upgrades to or recapitalization (complete overhaul) of existing equipment.

only slightly lower than would be the case without the 

upgrades (24 years).

Effect of Modularity

The Army’s modularity initiative—combined with its 

elimination of unneeded vehicles—could significantly affect the armored combat vehicle fleet. CBO estimates 

that converting to the planned modular structure will reduce the Army’s requirement for armored combat vehicles by more than a third—from upward of 23,000 in 

2003 to fewer than 15,000 in 2011, when the reorganization is scheduled to be complete. If the Army chose to retire, or decommission, vehicles that were not needed to 

equip or support its heavy units, it could reduce the overall size of its armored combat vehicle fleet by about half, 

from approximately 28,000 vehicles in 2005 to roughly 

14,500 vehicles in 2011 (see Figure 3-2 on page 37).

By eliminating more than 13,000 of its oldest vehicles between 2005 and 2011, the Army in that latter year could 

also reduce the average age of the fleet to 13 years instead 

of the 17 years that would result if all 28,000 armored vehicles were retained. If the Army chose to keep vehicles in 

its inventory that it did not need—and the Army has not 

retired large numbers of armored vehicles on such a compressed schedule in the past—it could mothball those 

older vehicles until they could be disposed of. The remaining smaller, or “active,” fleet with its lower average 

age could then be used to equip and support the new 

modular units.6

Effect of the FCS Program

Manned FCS vehicles could ultimately replace most of 

the armored vehicles that now equip the Army’s combat 

brigades. However, the Army would not begin to introduce the new vehicles until 2015 at the earliest, which in 

the context of the entire armored combat vehicle fleet 

would not significantly reduce the fleet’s overall age. Even 

after significant numbers of FCS vehicles—roughly 

500 per year starting in 2018—began to be fielded, the 

average age of the fleet would continue to increase (see 

Figure 3-3 on page 38).

High-Mobility Multipurpose Wheeled 

Vehicles (HMMWVs) 9,196

Medium Trucks 3,180

Heavy Trucks 1,148

Trailers for:

HMMWVs 8,806

Medium trucks 5,455

Heavy trucks 3,169

Forward-Area Refueling Systems 4,630

Medical Systems 1,059

Generators 18,817

Assault Kitchens 646

Abrams Tanks 512

Bradley Fighting Vehicles 1,260

M113-Based Vehicles 1,345

M88 Recovery Vehicles 170

Global Positioning System Receivers 21,215

Single-Channel Ground and Airborne Radio 

System Radios 22,436

Joint Tactical Radio System Cluster 5 Radios 20,250

FBCB2 Systems 8,683

Night-Vision Goggles 98,053

Surface-Launched Advanced Medium-Range 

Air-to-Air Missile Air Defense Launchers 48

Unmanned Aerial Vehicles 21

Other

Quantity

Armored Vehiclesa

Trucks and Support Equipment

Communications and Navigation Gear

6. Throughout this study, CBO uses the term “active fleet” to refer 

to those armored combat vehicles needed to equip and support 

the units in the modular Army.
34 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Table 3-4.

Upgrades Included in the Administration’s Plan for 2007 to 2016

Source: Congressional Budget Office based on Department of the Army, Weapons and Tracked Combat Vehicles, Army: Committee Staff 

Backup Book, Fiscal Year 2007 Budget Estimates (February 2006); and Office of the Secretary of Defense, Bradley Upgrade: Selected 

Acquisition Report (December 31, 2005).

Note: SEP = System Enhancement Program; ODS = Operation Desert Storm.

a. Upgrades are for the 2007-2011 period only.

How the introduction of FCS vehicles (as outlined in the 

Administration’s plan) would affect the active fleet of 

14,500 vehicles is more significant. Fielding 1.5 brigades’ 

worth of FCS vehicles annually could keep the average 

age of the active fleet at or below 16 years during the 

2011-2040 period (see Figure 3-4 on page 38).

According to the Army’s latest schedule, FCS vehicles 

could conceivably replace all of the Abrams tanks, Bradley fighting vehicles, self-propelled howitzers, and M113-

based vehicles in the Army’s combat brigades and prepositioned stocks by 2037.7 By then, the Army would 

have bought and fielded 32 brigades’ worth of FCS vehicles—enough to equip all 27 heavy combat brigades in 

the Army’s active component and the National Guard as 

well as an additional five brigades’ worth of prepositioned 

stocks. As FCS vehicles were introduced and existing systems retired, the average age of the active armored combat vehicle fleet would begin to decrease, reaching a minimum of about 15 years when all of the systems currently 

equipping heavy combat brigades and prepositioned 

stocks had been retired.8 At that point, the average age of 

the active fleet would start to increase, as FCS vehicles 

that were initially introduced more than 20 years earlier 

remained in service.

Concerns Regarding the Army’s

FCS Program

Defense analysts, Members of Congress, and the Government Accountability Office have all expressed reservations about the FCS program. Among their concerns are 

the technological challenges facing developers of the FCS 

components, the affordability of the FCS program in the 

light of the Army’s other funding needs, and the condition of the Army’s current fleet of armored vehicles, 

which would be retained for several decades until they 

could be replaced by FCS vehicles.

Technological Readiness of FCS Components

Questions have arisen about whether the FCS program 

was ready to enter the system development and demonstration phase when it did, in the spring of 2003, and as a 

consequence whether the planned FCS components will 

be ready to go into production in 2012 as called for in the 

current schedule. The Department of Defense’s (DoD’s) 

acquisition policy requires that a technology needed for 

developing a weapon system meet certain criteria if it is to 

System Upgrade

Abrams Tanks to the A2 SEP Modela 89 584

Bradley Fighting Vehicles

To the A2 ODS modela 619 1,141

To the A3 model 998 4,081

M113-Based Vehicles to the A3 Modela 841 379 ______ ______

2,547 6,184

Quantity

Cost 

(Millions of 2006 dollars)

7. That date is based on CBO’s assumption that the Army ultimately 

hopes to equip all 70 combat brigades with FCS components and 

that it will continue to purchase those components at the rate of 

1.5 brigades’ worth per year even after the first 15 brigades’ worth 

(Increment 1 of the procurement) have been bought. (The goal of 

equipping all of the Army’s combat brigades was formulated by 

then Army Chief of Staff General Shinseki when the FCS program was initiated in 2000.)

8. Several hundred M113-based vehicles and M109 self-propelled 

howitzers would be retained to equip units other than combat 

brigades.
CHAPTER THREE POTENTIAL EFFECTS OF AND CONCERNS ABOUT THE ARMY’S MODERNIZATION PLANS 35

Table 3-5.

Comparing the Army’s Premodular Heavy Brigade Combat Teams, Modular Heavy 

Combat Brigades, and Brigades Equipped with Future Combat Systems

Source: Congressional Budget Office based on data from the Department of the Army and Military Traffic Management Command Transportation Engineering Agency, Deployment Planning Guide: Transportation Assets Required for Deployment, MTMCTEA Pamphlet 

700-5 (May 2001).

Note: “Premodular” and “modular” refer to the Army’s ongoing modularity initiative, which seeks to make the service more flexible by 

changing its structure from one based on 18 divisions, several of unique design, to one based on 70 combat brigades, each one of only 

three designs. “Heavy” units are those equipped with tracked armored vehicles.

a. Numbers are rounded to the nearest 10 vehicles.

b. Includes helicopters and wheeled vehicles that cannot drive for long distances on roads.

c. Includes 150 unmanned ground vehicles and 20 armed reconnaissance helicopters in addition to wheeled vehicles that cannot drive for 

long distances on roads.

d. Based on an average load of 60 tons for heavy units and 50 tons to 55 tons for FCS-equipped combat brigades and rounded to the nearest 

10 sorties.

e. Either fast sealift ships or large medium-speed roll-on/roll-off ships will be needed but not both. Numbers of ships are rounded up to the 

nearest whole ship.

be considered “mature”: it should have been demonstrated in a relevant environment—referred to as attaining technology readiness level (TRL) 6—or, preferably, 

have been demonstrated in an operational environment 

(TRL 7).9 By the time the FCS program entered the 

SDD phase, the Army had identified 31 technologies that 

it judged were critical to the development of the FCS 

components.10 However, at that point, only one of those 

technologies had matured beyond TRL 6, and an additional seven critical technologies (23 percent) had attained TRL 6. According to GAO, “best practices of leading commercial firms and successful DoD programs have

Personnel (Number) 3,800 3,800 3,300

Vehicles (Number)a

Tracked 450 370 320

Trucks 840 880 550

Towed 390 410 180

Otherb 10 20 180 c

_______ _______ _______

Total Vehicles 1,690 1,680 1,230

Weight, All Equipment (Tons) 25,000 25,000 18,700

Coverage, All Equipment (Thousands of square feet) 323 320 260 to 290

By air (Number of C-17 sorties)d 420 420 340 to 370

Fast sealift 3 3 2

Large medium-speed roll-on/roll-off 2 2 1

Brigade Combat Team Combat Brigade

Premodular Heavy Modular Heavy 

FCS-Equipped Brigade

Deployment of Equipment

By sea (Number of ships)e

9. Technology readiness levels were pioneered by the National Aeronautics and Space Administration and subsequently adopted by 

DoD to measure whether technologies were sufficiently mature to 

be incorporated in a weapon system. See Appendix C for definitions of the TRLs.

10. The Army defines a critical technology as one that is new or

that is required in a new application to enable the FCS components to meet the operational requirements established for them. 

Appendix C lists the critical technologies applicable to the FCS 

program.
36 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Table 3-6.

Time Needed to Deploy Equipment of 

Combat Units to East Africa

(Days)

Source: Congressional Budget Office based on data from the 

Department of the Army; Military Traffic Management 

Command Transportation Engineering Agency, Deployment Planning Guide: Transportation Assets Required for 

Deployment, MTMCTEA Pamphlet 700-5 (May 2001); and 

Department of the Air Force, Air Mobility Planning Factors, Pamphlet 10-1403 (December 18, 2003).

Notes: Units would be moved from the continental United States. 

The data do not reflect the time needed to move sustaining 

units or supplies.

“Premodular” and “modular” refer to the Army’s ongoing 

modularity initiative, which seeks to make the service more 

flexible by changing its structure from one based on 18 divisions, several of unique design, to one based on 70 combat 

brigades, each one of only three designs.

FCS = Future Combat Systems.

a. The number of daily sorties constrained by the capacity of the 

airfield in East Africa, based on average airlift payloads per brigade of 60 tons for heavy units and 50 tons to 55 tons for FCSequipped units.

b. Besides combat brigades, divisions include headquarters and 

other support units.

shown that critical technologies should be mature to at 

least a TRL 7 before the start of product development.”11

Nevertheless, the FCS program entered the SDD phase 

in May 2003.

Despite the fact that the Army has restructured the FCS 

program several times since May 2003 and lengthened 

the time allotted to the SDD phase, GAO has criticized 

the ambitious schedule that the service proposes for developing and fielding the 18 FCS components. GAO officials testified in March 2005 that the schedule for the 

program that the Army was proposing at that time would 

require developing multiple systems and a network in the 

same amount of time that DoD typically spends in developing a single advanced system.12

Pace of Development. Even though the FCS program has 

progressed technologically since May 2003, concerns 

about the level of maturity of its systems persist. If everything were to go according to the Army’s plan, the FCS 

program would attain the level of technological readiness 

that it should have had before it entered the SDD 

phase—that is, all technologies judged to be at TRL 6 or 

higher—in 2009. But everything has not gone as 

planned, and the development of some critical technologies has been slower than anticipated. In October 2004, 

the Army assessed the critical technologies (which by 

then numbered 54) needed to develop the FCS components. It concluded that more than a year after entering 

the SDD phase, only one technology had attained TRL 7 

or above.13 And the fraction of all critical technologies attaining TRL 6 or higher remained roughly the same as it 

had been when the program entered the SDD phase a 

year earlier.

Premodular Armored Brigade Combat

Team with Existing Armored Vehicles 23 25

Modular Heavy Brigade with 

23 25

FCS-Equipped Brigade 18-20 25

110 27

135 27

115-130 27

Airlift Sealift a

Division-Sized Unitsb

Three Premodular Armored Brigade

Existing Armored Vehicles

Brigade-Sized Units

Combat Teams with Existing Armored 

Four Modular Heavy Brigades with

Four FCS-Equipped Brigades

Existing Armored Vehicles

Vehicles

11. Government Accountability Office, Defense Acquisitions: Improved 

Business Case Is Needed for Future Combat System’s Successful Outcome, GAO-06-367 (March 2006), p. 17.

12. Statement of Paul L. Francis, Director, Acquisition and Sourcing 

Management, Government Accountability Office, before the Subcommittee on AirLand of the Senate Committee on Armed Services, published as Government Accountability Office, Defense 

Acquisitions: Future Combat Systems—Challenges and Prospects for 

Success, GAO-05-442T (March 16, 2005). 

13. Office of the Deputy Assistant Secretary of the Army for Research 

and Technology, Future Combat Systems (FCS) Increment 1 Technology Readiness Assessment (TRA) Update (October 2004).
CHAPTER THREE POTENTIAL EFFECTS OF AND CONCERNS ABOUT THE ARMY’S MODERNIZATION PLANS 37

Figure 3-2.

Average Age and Composition of the

Active Armored Combat Vehicle Fleet 

(Thousands of vehicles) (Average age in years)

Source: Congressional Budget Office based on data from the 

Department of the Army.

Note: The “active fleet” comprises all models of the vehicles that 

CBO estimates will be needed to equip and support modular 

units in both the Army’s active component and the Army 

National Guard. (Modular units are those resulting from the 

Army’s ongoing modularity initiative, which seeks to make 

the service more flexible by changing its structure from one 

based on 18 divisions, several of unique design, to one 

based on 70 combat brigades, each one of only three 

designs.)

a. Reflects upgrades to existing systems based on documents submitted with the President’s 2007 budget.

In addition to assessing the program’s current status in 

such reports, the Army has also estimated when technologies might attain the required readiness levels. But the 

service’s past predictions have not been accurate. A relatively recent assessment (dated April 2005) of the technologies’ maturity showed that progress in achieving 

technical readiness, although noticeable, had been less 

than the October 2004 assessment predicted.14 When 

many of the technologies that the assessment projected 

would achieve TRL 6 by 2006 were subsequently evaluated in April 2005, the Army then predicted that they 

would achieve that level as many as three years later. 

Moreover, that prediction was made despite the fact that 

the number of technologies considered critical to developing the FCS components had been reduced. As the 

April 2005 assessment reports, five of the more challenging critical technologies—which were far from maturity 

at the time of the October 2004 assessment—have now 

been dropped from the list (see Appendix C for more 

details).15

The history of technologies associated with the communications equipment that FCS components will incorporate—specifically, software-programmable radios—illustrates the challenges that the Army faces in carrying out 

its modernization plans. The technologies for softwareprogrammable radios were judged to have attained 

TRL 6 in May 2003. The Army’s subsequent assessment 

of those technologies in October 2004 put their level of 

maturity at TRL 5 but predicted that they would reach 

TRL 6 in 2006.16 The Army’s April 2005 assessment, 

however, indicated that those technologies might not 

reach TRL 6 before 2007. Such setbacks reinforce the 

conclusion by GAO and the Army’s independent review 

team that the schedule established for developing all 

18 FCS components in the time DoD typically takes to 

develop a single system is a risky one. 

Varying Technological Challenges Posed by Different FCS 

Components. The development of individual FCS components does not necessarily require that all 49 critical 

technologies be mature. (For example, the development 

of unmanned aerial vehicles does not rely on the kind of 

technologies—such as lightweight hulls and armor—that 

would be needed for the development of manned and unmanned ground vehicles.) It is fair to assume, however, 

that the greater the number of mature technologies required to develop a system, the greater the risk that the 

system will not be ready on schedule.

14. Office of the Deputy Assistant Secretary of the Army for Research 

and Technology, Technology Readiness Assessment Update (April 

2005), cited in Government Accountability Office, Defense Acquisitions: Improved Business Case Is Needed, p. 16.

2003 2004 2005 2006 2007 2008 2009 2010 2011

0

5

10

15

20

25

30

35

40

45

0

2

4

6

8

10

12

14

16

Abrams Tanks

Bradley Fighting Vehicles

M113-Based Vehicles

M109 Self-Propelled

Howitzers

Fleet Average Agea

15. The five technologies that the Army no longer considers necessary 

for the initial fielding of the FCS components are the ability to 

generate water from vehicle exhaust, the ability to rapidly assess 

damage inflicted on enemy targets as a result of U.S. attacks, and 

three technologies that would have helped soldiers reliably identify friends and foes in combat.

16. Those technologies are necessary for the development and fielding 

of Clusters 1 and 5 of the Joint Tactical Radio System and the 

Warfighter Information Network-Tactical. 
38 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Figure 3-3.

Average Age and Composition of the

Armored Combat Vehicle Fleet 

Under the Administration’s Plan

(Thousands of vehicles) (Average age in years)

Source: Congressional Budget Office based on data from the 

Department of the Army.

Notes: Vehicle inventories represent totals of all models owned by 

the Army.

FCS = Future Combat Systems.

a. Reflects upgrades to existing systems based on documents submitted with the President’s 2007 budget.

The number of technologies needed to develop each of 

the various FCS components and the network can be 

used to gauge the relative technical challenge that each 

system poses. Based on that measure, the manned ground 

vehicles are the most technologically complex, requiring 

the maturity of 17 critical technologies. By comparison, 

the systems that the Army is planning to field first (the 

non-line-of-sight launch system, the unattended ground 

sensors, and the intelligent munitions system) are the 

least problematic because they depend on the maturity of 

only two critical technologies (see Figure 3-5 and 

Appendix C, which maps critical technologies to types of 

systems). In between, in order of increasing technical sophistication, are the UAVs (for which a very small, lightweight engine and a communications relay device are 

needed) and the unmanned ground vehicles (which require development of autonomous navigation systems, 

lightweight hulls, and mine-detection sensors and technologies for destroying or neutralizing mines). The network presents the most challenges: to make it fully functional requires that 27 critical technologies be mature, 

and by the end of 2005, only 11 had achieved TRL 6. 

The varying levels of technical maturity were part of the 

reason that the Army decided in the summer of 2004 to 

introduce the 18 systems in four phases, or spirals, to 

have additional time to develop the more technologically 

difficult systems. Similarly, increasingly demanding 

versions of the network are scheduled to be fielded in

Figure 3-4.

Average Age and Composition of the

Active Armored Combat Vehicle Fleet 

Under the Administration’s Plan

(Thousands of vehicles) (Average age in years)

Source: Congressional Budget Office based on data from the 

Department of the Army.

Note: The “active fleet” comprises all models of the vehicles that 

CBO estimates are needed to equip and support modular 

units in both the Army’s active component and the Army 

National Guard. (Modular units are those resulting from the 

Army’s ongoing modularity initiative, which seeks to make 

the service more flexible by changing its structure from one 

based on 18 divisions, several of unique design, to one 

based on 70 combat brigades, each one of only three 

designs.)

a. Reflects upgrades to existing systems based on documents submitted with the President’s 2007 budget.

2005 2010 2015 2020 2025 2030 2035 2040

0

5

10

15

20

25

30

35

40

0

5

10

15

20

25

30

35

40

45

Abrams Tanks

Bradley Fighting Vehicles

M113-Based Vehicles

M109 Self-Propelled

Howitzers

Fleet Average Age

Manned FCS

Vehicles

a

2005 2010 2015 2020 2025 2030 2035 2040

0

5

10

15

20

25

30

35

40

45

0

3

6

9

12

15

18

21

Abrams Tanks

Bradley

Fighting Vehicles

M113-Based

Vehicles

M109 Self-Propelled

Howitzers

Fleet Average Age

Manned FCS

Vehicles

a
CHAPTER THREE POTENTIAL EFFECTS OF AND CONCERNS ABOUT THE ARMY’S MODERNIZATION PLANS 39

Figure 3-5.

Status of Critical Technologies for FCS Components at the End of 2005

(Number of technologies)

Source: Congressional Budget Office based on data from the Department of the Army and Office of the Deputy Assistant Secretary of the 

Army for Research and Technology, Future Combat Systems (FCS) Increment 1 Technology Readiness Assessment (TRA) Update

(October 2004).

Note: A critical technology, according to the Army, is one that is new or that is required in a new application to enable the FCS components 

to meet the Army’s operational requirements.

FCS = Future Combat Systems; NLOS-LS = non-line-of-sight launch system; UGS = unattended ground sensors; IMS = intelligent 

munitions system; UAV = unmanned aerial vehicle; UGV = unmanned ground vehicle.

a. For a technology to be considered mature enough to use in developing a weapon system, the Department of Defense’s (DoD’s) acquisition 

policy recommends that it be successfully demonstrated in a relevant environment, a criterion referred to as achieving TRL (technology 

readiness level) 6. (TRL measures were pioneered by the National Aeronautics and Space Administration and subsequently adopted by 

DoD.)

increments along with increasingly sophisticated FCS 

components.

Development of Software. Another technological hurdle 

that the Army must overcome is development of the software that will allow all of the FCS components to communicate with each other, share data, and operate with 

existing systems. At least 34 million lines of software code 

must be generated, or about twice the amount needed for 

the Joint Strike Fighter, DoD’s largest software undertaking to date. According to GAO, the software required for 

the overall operating environment may not reach the level 

of technical maturity necessary in time to meet the scheduled milestones in the FCS program—which makes the 

successful development of that common environment 

uncertain.17 Furthermore, because broad requirements 

for the FCS components were still evolving in mid-2005, 

the more-detailed specifications required to write software had not yet been established. Consequently, GAO 

also reported in June 2005 that it was unclear whether 

the software would be sufficiently developed to support 

the fielding of the first spiral of FCS components in 

2008.

NLOS-LS,

UGS, IMS

UAVs UGVs Manned

Ground Vehicles

Complete

Network

0

5

10

15

20

25

30

Less than TRL 6 TRL 6 or Greater a a

17. Government Accountability Office, Defense Acquisitions: Resolving 

Development Risks in the Army’s Networked Communications Capabilities Is Key to Fielding Future Force, GAO-05-669 (June 2005).
40 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Figure 3-6.

The Army’s Major Procurement Programs and Budget Through 2025

(Billions of 2006 dollars)

Source: Congressional Budget Office based on Office of the Secretary of Defense, Selected Acquisition Reports, various systems

(September 30, 2005, and December 31, 2005).

Notes: Major procurement programs are those for which the Army is required to submit Selected Acquisition Reports to the Congress.

FCS = Future Combat Systems.

a. Includes the Joint Tactical Radio System Clusters 1 and 5 and the Warfighter Information Network-Tactical program.

b. Under this phase of the FCS program, the Army would purchase a total of 15 brigades’ worth of FCS equipment at a rate of 1.5 brigades’ 

worth per year.

c. During this phase, the Army would continue to purchase 1.5 brigades’ worth of FCS components annually through 2025.

Affordability of the FCS Program

Funding for the FCS program will consume a significant 

portion of the Army’s procurement budget well into the 

2020s. According to the latest SARs, the FCS program 

will require $8 billion to $10 billion annually starting in 

2015 (when the Army would start to buy 1.5 brigades’ 

worth of equipment each year). During the preceding five 

years, the FCS program would consume increasingly 

larger amounts of the service’s procurement funding (see 

Figure 3-6). In 2011, planned FCS costs would account 

for about 6 percent of the Army’s $21 billion procurement budget, CBO estimates; by 2015, that share could 

rise to almost half and remain at or above 40 percent 

through 2025. (For purposes of comparison, in the mid1980s, at the height of the Reagan defense buildup, the 

Army dedicated at most 20 percent of its procurement 

funds to buy combat vehicles.) 

Devoting such a large portion of its procurement funding 

to the FCS program would leave the Army little to invest 

in other weapon systems (such as upgrades to its tanks) or 

to purchase needed support equipment (such as small 

trucks, generators, and ammunition).18 In 2008, the 

Army is slated to spend almost $14 billion of its total 

$20 billion in procurement funds on smaller programs 

that are not required to submit SARs to the Congress. In 

2005 2010 2015 2020 2025

0

5

10

15

20

25

30

Planned Total Procurement Funding

FCS Increment 1b

Other Major Procurement Programs

Additional Programs

Needed to Develop

FCS Network

FCS Increment 2c

a

18. CBO’s analysis, like similar studies by the Army and GAO, incorporates the assumption that after 2011, the Army’s procurement 

account will grow at the rate of annual inflation.
CHAPTER THREE POTENTIAL EFFECTS OF AND CONCERNS ABOUT THE ARMY’S MODERNIZATION PLANS 41

addition to the FCS program, the Army has allocated 

large amounts of its future procurement funds to other 

major programs (such as the Warfighter Information 

Network-Tactical, the Joint Tactical Radio System, and 

the Blackhawk helicopter). Given the budgetary demands 

of those programs and under the assumption (which the 

Army incorporates in its analyses) that the procurement 

account will grow at the rate of inflation after 2011, only 

$3 billion would be available in the account in 2015—

compared with $14 billion in 2008—to pay for the many 

items that the Army needs, such as ammunition, generators, trailers, and many other goods.19

Past Cost Growth. The FCS program has experienced a 

significant increase in costs since it entered the SDD 

phase in the spring of 2003. At that time, Army estimates 

put the cost of a program to develop and purchase the 

FCS network and all of the components except the recovery and maintenance vehicle in quantities sufficient to 

equip 15 brigades (from 2005 through 2025) at $80 billion. One and a half years later, in the December 2004 

SAR, the program’s estimated costs over the same period 

had risen slightly, to $83 billion, on the basis of plans that 

reduced the scope of the effort to 14 systems and the network and delayed it by one year. Just nine months later, 

in September 2005, the Army announced that the cost 

from 2005 through 2025 of developing and procuring all 

18 components and the network for the first 15 brigades 

had jumped to $128 billion, a 60 percent increase over 

the original estimate of $80 billion. At the same time, the 

Army reduced the maximum annual rate of procurement 

of FCS components from two brigades’ worth of equipment to 1.5 brigades’ worth.20

Risk of Additional Cost Growth. The costs of the FCS 

program could continue to grow, if those of past major 

defense programs are any guide. In analyses of historical 

trends in the costs of DoD’s weapon programs, RAND 

and the Institute for Defense Analyses (IDA) demonstrated that R&D costs grew from 16 percent to about 

70 percent and procurement costs rose by between 

11 percent and roughly 70 percent, as measured from estimates prepared when the program entered the SDD 

phase. (The higher end of those ranges reflects cost 

growth experienced by ground vehicles; see Appendix D 

for further discussion of historical cost growth rates and 

RAND’s and IDA’s analyses.) If, as GAO and others 

maintain, the FCS program entered the SDD phase prematurely—in part because the program at that time was 

still insufficiently well defined—historical precedent suggests that costs for the program could continue to grow at 

high rates. Because the FCS program is developing and 

procuring several different types of systems, CBO used a 

weighted average of the rates of cost growth that apply to 

different types of systems to determine an estimated rate 

of overall cost growth risk—roughly 60 percent. That 

rate reflects the fact that ground vehicles are the most 

costly component of the FCS program and in the past experienced rates of cost growth that exceeded 70 percent.

If costs for the FCS program grew as those for similar 

programs have in the past, the annual funding needed 

from 2015 through 2025 could rise from the current 

estimate of $8 billion to $10 billion to $13 billion to 

$16 billion. From 2015 to 2022, the Army intends to 

procure 1.5 brigades’ worth of FCS components each 

year, a plan that could require $15 billion annually in the 

years from 2016 to 2018 if costs grew at historical rates. 

The total funds allotted to the Army’s procurement account in 2011 are currently estimated at $21 billion (in 

2006 dollars) and if the account grew only at the rate of 

inflation would remain at that level. Devoting $15 billion—or more than 70 percent—of that amount solely to 

purchases of FCS components in 2016 would leave just 

$6 billion in procurement funds for other programs, both 

large and small, that are currently slated to receive a total 

of $20 billion in 2011.

19. Based on Department of the Army, The Army Modular Force and 

Future Combat Systems Strategy (undated), p. 15.

20. An independent estimate of the cost of the FCS program submitted to the Congress in June 2006 by the Cost Analysis Improvement Group (CAIG) in the Office of the Secretary of Defense 

indicates that the costs of the program may be higher than the latest Army estimates suggest. The CAIG estimated that R&D costs 

could range from $34 billion to $47 billion and procurement 

costs might be $126 billion (all costs are in 2006 dollars). Because 

the CAIG’s estimate includes some procurement costs that are not 

included in the Army’s figures, the two estimates may not be 

totally comparable. But the additional items that the CAIG 

included and the Army did not (missiles and munitions for training and war reserves as well as funds for some modifications) are 

not likely to represent a significant portion of the CAIG’s overall 

estimate of procurement costs. In any case, the CAIG indicated in 

its report that its June 2006 estimate represented an increase of 

more than 70 percent over its estimate of the costs of the FCS program made in the spring of 2003, prior to the program’s entry into 

the SDD phase. See Office of the Secretary of Defense, Cost Analysis Improvement Group, “Report to Congress on Future Combat 

Systems: Independent Cost Estimate” (June 2006).
42 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Potential Reductions in Procurement Rates for FCS

Components. The Army has already amended the schedule for the FCS program to address concerns about affordability, reducing the maximum annual rate of purchases from three brigades’ worth (as proposed in 

November 2002) to 1.5 brigades’ worth (established in 

September 2005). Despite those reductions, the annual 

cost of the program would remain above $8 billion in 

2014 and for several years thereafter. If costs continued to 

grow, the rate of annual purchases might need to be further reduced.

As an example of purchases under a less expensive program, the Army could buy a maximum of one brigade’s 

worth of equipment per year. At that rate, components to 

equip the initial increment of 15 brigades would not be 

purchased until 2027 and would not be fully fielded until 

2030. Of course, the annual funding for the FCS program would also be reduced from the levels outlined in 

the latest SARs ($8 billion to $10 billion) to $5 billion to 

$7 billion (see Figure 3-7). If, however, program costs 

grew at a rate typical of such development and procurement efforts, the annual funding requirements would still 

be substantial—on the order of $10 billion, or roughly 

the estimated costs, but without potential growth, outlined in the September 2005 SAR for buying 1.5 brigades’ worth of components per year.

Concerns About Maintaining the Army’s Current 

Fleet of Armored Vehicles

The total size of the FCS program—in terms of brigades’ 

worth of equipment purchased—and the rate at which 

the program is executed will determine how many of the 

Army’s existing fleet of armored vehicles will be retained 

and for how long. As mentioned earlier, the Army at the 

end of 2005 still maintained a sizable armored combat 

vehicle fleet (approximately 5,850 Abrams tanks, 6,650 

Bradley fighting vehicles, 13,700 M113-based vehicles, 

and roughly 1,500 M109 self-propelled howitzers). FCS 

components would begin to replace some of those vehicles in 2015, but for armored vehicles in the combat brigades and in the prepositioned equipment sets, the process would not be complete until 2037 at the earliest, and 

until then, existing vehicles would have to be maintained. 

Some M113-based vehicles and M109 howitzers that 

equip units other than combat brigades might be retained 

indefinitely.

The Army’s budgetary plans, however, do not include sufficient funds to maintain all of the vehicles it currently 

has in its inventory. In fact, on the basis of the upgrades 

noted in plans submitted with the President’s 2007 budget and the schedule for introducing manned FCS vehicles into units, CBO estimates that the average age of the 

Army’s total fleet of armored combat vehicles could reach 

23 years by 2020 and 30 years by 2040 (see Figure 3-3 on 

page 38).

A more useful measure of the status of the Army’s armored combat vehicle fleet might be the average age of 

the active vehicle fleet. As discussed earlier, the Army’s 

modularity initiative will reduce the total number of vehicles that the service needs; CBO estimates that if the 

service used only the latest versions of the armored vehicles in its current fleet, the average age of the active fleet 

(approximately 14,500 vehicles rather than the total 

fleet of 28,000 vehicles) would be 16 years in 2020 and 

would remain at or below that level through 2040 (see 

Figure 3-4 on page 38). Even though the average age of 

the active fleet would be much lower than the average age 

of the entire inventory, it would still almost always exceed 

15 years after 2015, the age that the Army considers the 

top of the desirable range.

Cost of Additional Upgrades. The average age of the armored combat vehicle fleet could be reduced if the Army 

invested in upgrades for its existing vehicles. To keep the 

average age of the fleets of existing vehicles relatively constant after 2011, the Army must, in CBO’s estimation, 

upgrade and overhaul roughly 800 Abrams tanks, 2,500 

Bradley fighting vehicles, 3,000 M113-based vehicles, 

and 550 M109 howitzers between 2007 and 2025, investing $21 billion over that period.21 If it did so, the service could reduce the average age of its active fleet of 

combat vehicles from more than 15 years in 2016 without those additional upgrades to one that would be consistently below 13 years through 2040 (see Figure 3-8).

Effect of a Diminished FCS Program. If the Army’s concerns about affordability persuaded it to stretch out the 

FCS program or truncate it at 15 brigades’ worth of 

21. Such investments—which include those requested in the President’s budget for 2007—would either upgrade a less capable 

model to the most capable model or, for a vehicle that was already 

the latest model, totally overhaul it so that its age would be reset to 

zero. For details of CBO’s estimates of the costs to upgrade existing armored combat vehicles, see Appendix D.
CHAPTER THREE POTENTIAL EFFECTS OF AND CONCERNS ABOUT THE ARMY’S MODERNIZATION PLANS 43

Figure 3-7.

Estimated Total Annual Costs for the Future Combat Systems Program Including 

Potential Cost Growth

(Billions of dollars)

Source: Congressional Budget Office.

Note: Total costs comprise those for research and development and for procurement.

a. Weighted average of the historical rates of cost growth that apply to the various systems being developed in the FCS program.

2005 2010 2015 2020 2025

0

5

10

15

20

2005 2010 2015 2020 2025

0

5

10

15

20

0% Cost Growth

60% Cost Growtha

0% Cost Growth

60% Cost Growtha

Procuring 1 Brigade's Worth of Equipment per Year

Procuring 1.5 Brigades' Worth of Equipment per Year
44 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Figure 3-8.

Average Age of the Active Armored 

Combat Vehicle Fleet Under the 

Administration’s Plan with Additional 

Upgrades

(Average age in years)

Source: Congressional Budget Office based on data from the 

Department of the Army.

Note: The “active fleet” comprises all models of the vehicles that 

CBO estimates will be needed to equip and support modular 

units in both the Army’s active component and the Army 

National Guard. (Modular units are those resulting from the 

Army’s ongoing modularity initiative, which seeks to make 

the service more flexible by changing its structure from one 

based on 18 divisions, several of unique design, to one 

based on 70 combat brigades, each one of only three 

designs.)

a. Includes the effects of introducing Future Combat Systems 

components into units as well as upgrades to existing systems 

based on documents submitted with the President’s 2007 

budget.

b. Includes the effects of upgrades to existing systems based on 

documents submitted with the President’s 2007 budget and 

upgrades to Abrams tanks, Bradley fighting vehicles, M113-

based vehicles, and M109 howitzers to maintain a relatively constant average age for each fleet of vehicles after 2011.

c. Includes the effects of introducing FCS components into units 

as well as upgrades to existing systems based on documents 

submitted with the President’s 2007 budget and upgrades to 

Abrams tanks, Bradley fighting vehicles, M113-based vehicles, 

and M109 howitzers to maintain a relatively constant average 

age for each fleet of vehicles after 2011.

components, such a decision would have implications for 

the average age of the current fleet of armored combat vehicles. Fifteen brigades’ worth of FCS components would 

not be enough to equip all of the Army’s heavy combat 

brigades; at least 12 of them—potentially four in the 

Army’s active component and eight in the National 

Guard—and five brigade-sized sets of prepositioned 

equipment would have to retain their Abrams tanks, 

Bradley fighting vehicles, M109 howitzers, and M113-

based vehicles. In fact, roughly 9,000 of those older vehicles might have to be retained indefinitely. If the Army 

purchased the 15 brigades’ worth of components at the 

rate of one per year, the average age of such a fleet, without additional upgrades to those older vehicles and even 

in combination with the newer FCS components, would 

be roughly 30 years in 2040, by CBO’s estimates (see 

Figure 3-9). Moreover, by 2040, the FCS vehicles purchased to equip the first brigades would be more than 

20 years old.

If, for example, the Army bought only 15 brigades’ worth 

of FCS components at the rate of one brigade’s worth per 

year, it would need to invest considerable sums—roughly 

$25 billion through 2025—to upgrade the large number 

of vehicles that it planned to retain for some years in order to keep the average age of those systems relatively 

constant after 2011. (That investment would be about 

$4 billion more than would be needed if the Army 

bought FCS components at the rate of 1.5 brigades’ 

worth per year.) The need for more upgrades and therefore more funds would persist through 2040. Furthermore, if the Army purchased only 15 brigades’ worth of 

FCS equipment, it would need to invest roughly $1 billion annually to upgrade the armored vehicles that would 

remain in its inventory indefinitely.

Survivability of Manned FCS Vehicles

Several observers have questioned the basic assumption 

that underlies the survivability of lightweight manned 

FCS vehicles.22 Supporters of the program claim that 

knowledge of an enemy’s whereabouts—gained through 

the information sharing made possible by the FCS network—will allow FCS vehicles to avoid unexpected or 

disadvantageous encounters. In that way, they argue, the 

2005 2010 2015 2020 2025 2030 2035 2040

0

8

10

12

14

16

18

Fleet Average Age

Fleet Average Age with

Additional Upgrades

a

c

Existing-Vehicle

Fleet Average Age

wtih Additional Upgradesb

22. See Richard Hart Sinnreich, “FCS Needs More Than Just Additional Technical Work,” Lawton (OK) Constitution (July 25, 

2004); “A Science-Fiction Army” (editorial), New York Times

(March 31, 2005); and Scott Boston, “Toward a Protected Future 

Force,” Parameters (Winter 2004-2005), p. 55.
CHAPTER THREE POTENTIAL EFFECTS OF AND CONCERNS ABOUT THE ARMY’S MODERNIZATION PLANS 45

Figure 3-9.

Average Age and Composition of the

Active Armored Combat Vehicle 

Fleet with Limited Purchases of 

FCS Components

(Thousands of vehicles) (Average age in years)

Source: Congressional Budget Office based on data from the 

Department of the Army.

Notes: The “active fleet” comprises all models of the vehicles that 

CBO estimates will be needed to equip and support modular 

units in both the Army’s active component and the Army 

National Guard. (Modular units are those resulting from the 

Army’s ongoing modularity initiative, which seeks to make 

the service more flexible by changing its structure from one 

based on 18 divisions, several of unique design, to one 

based on 70 combat brigades, each one of only three 

designs.)

FCS = Future Combat Systems.

a. Reflects upgrades to existing systems based on documents submitted with the President’s 2007 budget.

b. Includes upgrades to Abrams tanks, Bradley fighting vehicles, 

M113-based vehicles, and M109 howitzers to maintain a relatively constant average age for each fleet of vehicles after 2011.

more lightly armored manned FCS vehicles will be just as 

long-lived on the battlefield as their more heavily armored counterparts are today. Some defense analysts, 

however, have called into question the viability and technical feasibility of a network that would enable each of 

hundreds—if not thousands—of systems to know its own 

location with respect to those of its fellow friendly vehicles as well as those of the enemy’s. Without that knowledge and the resultant ability to avoid unfavorable encounters with adversaries, the survivability of lightly 

armored FCS vehicles might be called into question.

Another concern expressed by soldiers and commanders 

who have returned from Iraq is whether FCS-type sensors 

will be able to detect and locate suicide bombers and car 

bombs, which have proven to be the greatest threat that 

U.S. forces are facing in Iraq.23 As a consequence, they 

argue, the sensors and network that are part of the FCS 

program will not be able to make FCS vehicles survivable, and because contacts with the enemy will be inevitable, greater protection, such as that provided by current 

armored vehicles, is necessary.

Congressional Concerns

Members of the House Appropriations and Armed Services Committees, reflecting their doubts about the technical maturity of the components of the FCS program, 

did not provide all of the funding for it that the Administration requested for 2006. Authorizers specifically targeted manned ground vehicles and blocked funding for 

them until “mature technologies have been demonstrated 

in a relevant environment” and proved capable of providing lethality and survivability at least equal to those of the

2005 2010 2015 2020 2025 2030 2035 2040

0

5

10

15

20

25

30

35

0

4

8

12

16

20

24

28

32

Abrams Tanks

Bradley

Fighting Vehicles

M113-Based

Vehicles

M109

Self-Propelled

Howitzers

Fleet Average Age

Manned FCS

Vehicles

Fleet Average Age with

Additional Upgrades

a

b

23. Joshua Kucera, “Iraq Conflict Raises Doubts on FCS Survivability,” Jane’s Defense Weekly (May 19, 2004), p. 8; and statement of 

Congressman Neil Abercrombie at a hearing before the Subcommittee on Tactical Air and Land Forces of the House Armed Services Committee, “Fiscal Year 2007 Budget Request for Future 

Combat Systems, Modularity, and Force Protection Initiatives,” 

April 4, 2006.
46 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Army’s current fleet of vehicles.24 In addition, appropriators and authorizers questioned whether sufficient funding would be available in coming years to afford both the 

FCS program and the Army’s modularity initiative.25

Those concerns, as well as the immaturity of needed technologies, the instability of the program’s schedule, and 

the lack of an independent cost estimate, have caused 

some Members of Congress to question the large sums of 

money that the Army plans to devote to the FCS program and have prompted a search for potential alternatives, some of which are discussed in the next chapter.26

24. House Armed Services Committee, National Defense Authorization Act for Fiscal Year 2006, Report 109-89 (May 20, 2005), 

p. 257.

25. House Appropriations Committee, Department of Defense Appropriation Bill, 2006, Report 109-119 (June 10, 2005), p. 231; and 

statement of Congressman Neil Abercrombie, April 4, 2006.

26. Congressman Neil Abercrombie, as reported in Inside the Army, 

“Authorizers Differ Over Funding for Future Combat System Program,” May 16, 2005; Congressman Curt Weldon, as reported in

Inside the Army, “Congress May Consider Changes to FCS in 

Authorization Bill,” May 9, 2005; and opening statement of 

Chairman Curt Weldon at a hearing before the Subcommittee on 

Tactical Air and Land Forces of the House Armed Services Committee, “Fiscal Year 2007 Budget Request for Future Combat Systems, Modularity, and Force Protection Initiatives,” April 4, 2006.
CHAPTER

4

Alternative Approaches to

Modernizing the Army’s Heavy Forces

The Congressional Budget Office analyzed four options for modernizing the Army’s armored units that 

would address concerns about the Future Combat Systems program, including its technical feasibility and affordability as it is currently structured and the slow rate of 

introduction of FCS components into the Army’s force 

structure. Three of the alternatives that CBO examined 

would retain various portions of the FCS program while 

canceling the remainder. The fourth alternative would 

cancel development and procurement of the program’s 

new weapon systems but retain the FCS network and associated software and integration elements. 

The three options that would retain significant portions 

of the FCS program—Alternatives 1 through 3—were 

structured to emphasize systems that would contribute to 

different capabilities (see Table 4-1). Under the first alternative, the Army would develop and purchase the full 

suite of sensors called for in the FCS program—the unattended ground sensors and all four classes of unmanned 

aerial vehicles, together with the network—to enhance 

units’ ability to collect and disseminate information. The 

second alternative, in addition to the network, would emphasize FCS components that could improve the Army’s 

ability to carry out long-range strikes; under that option, 

the Army would develop and purchase the unattended 

ground sensors and longer-range UAVs (Classes III 

and IV) for detecting and tracking targets and the nonline-of-sight launch system for attacking them. Under the 

third alternative, the Army would focus on enhancing the 

maneuvering ability of its brigades by developing several 

of the manned FCS ground vehicles (particularly those 

that would replace the older M113-based vehicles and 

M109 self-propelled howitzers now in the combat vehicle 

fleet) and the network to tie them together. Under the 

fourth alternative, the Army would develop only the network and forgo acquisition of any other FCS components. Under none of the alternatives would the service 

develop or procure the unmanned ground vehicles or intelligent munitions systems that are currently planned for 

the FCS program.

Under all four alternatives, however, the Army would upgrade existing armored vehicles to convert them to the 

latest models and prevent their average age from rising. 

Those modernization efforts would also integrate any 

capabilities gained from the various FCS components 

that were retained—that is, when those systems became 

available.

CBO evaluated each of the alternatives on three dimensions: cost, effect on the Army’s armored fleet, and effect 

on the speed of deployment of heavy units. In assessing 

costs, CBO estimated the total funds needed during the 

2007–2025 period to develop and purchase the systems 

included under each alternative. (Appendix D discusses 

CBO’s cost-estimating methods.) To discern how procuring large numbers of FCS vehicles would affect the armored combat vehicle fleet, CBO evaluated the impact of 

that procurement in terms of inventory and average age 

from 2007 through 2040. Effects on deployment speed 

were measured by calculating the time needed under the 

various alternatives to deploy brigade- and division-sized 

units by air and by sea from Savannah, Georgia, to the 

East African nation of Djibouti.

Alternative 1. Develop and Procure 

FCS Components That Will Collect and 

Disseminate Information

Under the first alternative that CBO assessed, the Army 

would retain only those portions of the FCS program 

that enhanced its ability to collect information about the 

location of potential threats and to disseminate that in-
48 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Table 4-1.

Alternatives to the Administration’s Current Plan for the FCS Program

Source: Congressional Budget Office.

Note: FCS = Future Combat Systems; UAV = unmanned aerial vehicle.

a. Under Alternative 3, the Army would buy roughly 25 percent of the infantry carrier vehicles included in the Administration’s plan.

formation to its combat brigades. As noted earlier, some 

people argue that if Army units knew more about the location and character of potential threats and the whereabouts of friendly forces, they would be better able to respond and act appropriately, either individually or in 

concert. To collect as much information as possible, the 

Army under this alternative would continue to develop 

and procure the unattended ground sensors and all four 

classes of UAVs (see Table 4-2). It would also retain the 

network portion of the FCS program and upgrade its existing armored vehicles to allow them to be integrated 

into it. All other FCS components, including the manned 

and unmanned ground vehicles, the NLOS launch system, and the intelligent munitions system would be

canceled.

By greatly increasing the number and types of sensors

deployed with a combat brigade, this alternative could 

significantly enhance the information available to soldiers 

and commanders in the field about the location of enemy 

units, friendly forces, civilians, and features of the terrain—as well as about events as they unfolded. In 

particular:

Alternative Retained

Alternative 1 Collection and sharing Scaled-down network All manned vehicles

of information All classes of UAVs

Unattended ground sensors

Alternative 2 Long-range strikes Scaled-down network All manned vehicles

UAV Classes III and IV UAV Classes I and II

Unattended ground sensors

Non-line-of-sight launch system

Alternative 3 New vehicular technology Scaled-down network

Manned vehicles

Medical Mounted combat system

Infantry carriera Recovery and maintenance

Non-line-of-sight mortar Reconnaissance and surveillance

Non-line-of-sight cannon

Command and control

Alternative 4 Network integration with Scaled-down network

existing systems

Emphasis

FCS Components

Intelligent munitions system

All unmanned ground vehicles

Intelligent munitions system

All unmanned ground vehicles

Manned vehicles

All classes of UAVs

Canceled

All unmanned ground vehicles

Non-line-of-sight launch system

Non-line-of-sight launch system

Unattended ground sensors

Intelligent munitions system

All manned vehicles

Intelligent munitions system

All unmanned ground vehicles

All classes of UAVs

Unattended ground sensors

Non-line-of-sight launch system
CHAPTER FOUR ALTERNATIVE APPROACHES TO MODERNIZING THE ARMY’S HEAVY FORCES 49

Table 4-2.

Procurement of FCS Components Under the Administration’s Plan and

Under Alternative 1

Source: Congressional Budget Office.

Notes: Under Alternative 1, the Army would emphasize the collection and sharing of information.

FCS = Future Combat Systems; UAV = unmanned aerial vehicle.

a. A spiral is the Army’s term for a planned introduction (into units in the field or current systems or both) of technology developed as part 

of a larger program.

B The smallest Class I UAVs, which are designed to be 

operated by one- or two-person teams, could allow individual soldiers to scout nearby terrain, even in an urban setting. In addition, under this alternative, the 

Army would increase the number of aerial vehicles assigned to a brigade by a factor of five and the number 

of stations for launching and controlling them by a 

factor of more than eight. (Today’s fully equipped 

modular heavy combat brigade has four mediumrange Shadow UAVs with only one control station and 

36 small Raven UAVs with 12 control stations.) The 

Army would also slightly extend the range of its UAV 

coverage, boosting it from roughly 50 kilometers (the 

range of the current Shadow UAV) to 75 km (the 

range planned for the largest Class IV UAV).

B The unattended ground sensors, when widely dispersed, could provide remote early warning of any intruders on the ground or in the air over an area of up 

to 1 square kilometer.

B A version of the FCS network that would be developed and procured as part of this alternative and integrated into existing combat vehicles would allow the 

information collected by the numerous sensors to be 

disseminated and shared by all members of the

brigade.

The UAVs and unattended ground sensors are among the 

least technologically challenging and least expensive of 

the proposed FCS components. As a result, under this alternative, procurement of some of those components 

would start earlier than under the Administration’s plan: 

ground sensors and portions of the network in 2008, 

Class III UAVs in 2010, and the remaining UAVs in 

2012.1

 To speed the introduction of FCS technologies 

into its brigades, the Army would procure components at 

the rate of three brigades’ worth per year—twice the purchase rate that the Administration is planning. Thus, under this alternative, the Army by 2025 would have purchased 33 brigades’ worth of Class I, II, and IV UAVs, 

Spirala Fielding to Units Starts Administration's Plan Alternative 1

1 2010 Non-line-of-sight launch system Unattended ground sensors

Unattended ground sensors Spiral 1 network

Intelligent munitions system

Spiral 1 network

2 2012 UAV Class III UAV Class III

Spiral 2 network improvements Spiral 2 network improvements

3 2014 Unmanned ground vehicles UAV Classes I, II, and IV

Spiral 3 network improvements

4 2016 UAV Classes I, II, and IV None

Manned vehicles

Complete network

Components To Be Procured

1. CBO assumed that components would be introduced into units 

two years after they were procured.
50 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

39 brigades’ worth of Class III UAVs, and 45 brigades’ 

worth of unattended ground sensors and the network—

enough, in the case of the ground sensors and a rudimentary version of the network, to equip the Army’s entire active component plus three additional brigades in the 

Army National Guard.

To operate effectively with the new FCS components and 

network and to keep the average age of each fleet of vehicles from increasing after 2011, the armored vehicles that 

now equip the Army’s combat brigades would have to be 

upgraded. CBO estimates that roughly 80 Abrams tanks, 

210 Bradley fighting vehicles, 230 M113-based vehicles, 

and 40 M109 self-propelled howitzers would need to be 

upgraded annually for the foreseeable future.

Costs Under Alternative 1

Under this option, the Army would spend a total of 

$99 billion (excluding any cost growth that might occur) 

from 2007 through 2025—a substantially smaller 

amount than the estimate of costs ($140 billion) for the 

entire FCS program (without upgrades) for the same period. According to CBO’s calculations, the cost of the 

FCS components developed and purchased under this alternative would be $61 billion ($15 billion for research 

and development and $46 billion for procurement), and 

the total cost of upgrading the existing armored combat 

vehicle fleet from 2007 through 2025, including the cost 

for research and development, would be $38 billion (see 

Table 4-3). The annual cost of implementing the alternative would be just under $6 billion after 2015—which 

would be less than the annual cost of the complete FCS 

program ($8 billion to $10 billion) and represent even 

greater savings when compared with the annual costs of 

the program plus upgrades to existing systems ($8 billion 

to $12 billion; see Figure 4-1 on page 52).2

The potential for cost growth under Alternative 1 would 

probably be less than that under the Administration’s 

plan during the 2007-2025 period because the Army 

would be developing and purchasing types of systems 

that historically have experienced relatively low rates of 

such growth. Specifically, total costs under this alternative 

might grow by slightly more than 30 percent—from 

$99 billion to $131 billion—as a result of increases in the 

acquisition cost of the UAVs, the network, and the unattended ground sensors. By contrast, the cost of the FCS 

program as a whole could grow by roughly 60 percent 

from 2007 through 2025, the result of developing and 

procuring large numbers of ground vehicles under the 

Administration’s plan, an element that is not part of 

Alternative 1.

Effect of Alternative 1 on Deployment of Army Units

Because under this alternative the Army would retain the 

armored combat vehicles that are now in its heavy units, 

the speed of deployment of such units would be little affected. However, the weight of a modular heavy brigade 

and associated division would increase because of the additional vehicles needed to support and transport the 

large number of UAVs that would be added to each 

brigade.

Currently, modular heavy brigades are equipped with a 

small number of UAVs similar to the Class III UAV 

planned for the FCS program and larger numbers of 

smaller UAVs similar to the FCS Class I UAV. According 

to the Army’s standard equipment tables, each of its modular brigades should be equipped with one Shadow UAV 

system, which includes four aircraft and a launch and 

control station supported by generators, communications 

equipment, and five high-mobility multipurpose wheeled 

vehicles for transport.3 Modular heavy brigades are also 

equipped with 12 Raven systems, each with three aerial 

vehicles. Those aircraft are much smaller than the 

Shadow UAVs—they weigh only four pounds—and can 

be launched by hand. Since they are so small, there are no 

vehicles in the brigade dedicated to their transport.

Under the structure that the Army is now proposing, an 

FCS-equipped brigade would have many more UAVs and 

several more trucks to support them than does a modular

2. An even cheaper alternative would be to purchase the unattended 

ground sensors, UAVs, and network components included under 

this alternative at the same rate as that planned for the Administration’s FCS program. At that rate—1.5 brigades’ worth of equipment per year—the total cost of Alternative 1 from 2007 through 

2025 would drop to $78 billion, and annual costs after 2015 

would be just under $4 billion. However, at that low rate, as under 

the Administration’s plan, a smaller number of brigades—18 to 

24—could be equipped with the components purchased through 

2025.

3. Based on Office of the Secretary of Defense, Unmanned Aircraft 

Systems Roadmap 2005-2030 (August 4, 2005), p. 67, and data 

from the Department of the Army.
CHAPTER FOUR ALTERNATIVE APPROACHES TO MODERNIZING THE ARMY’S HEAVY FORCES 51

Table 4-3.

Total Acquisition Costs from 2007 to 2025 for the Administration’s Plan and 

Alternatives

(Billions of 2006 dollars)

Source: Congressional Budget Office based on data from the Department of the Army.

Notes: The estimated costs presented in this table do not take into account the possibility that costs may grow as they have in similar defense 

programs in the past.

FCS = Future Combat Systems.

a. Includes costs to develop and purchase 15 brigades’ worth of FCS components—enough to equip slightly more than half of the Army’s 

planned 27 heavy brigades (19 brigades in the active Army and eight brigades in the Army National Guard).

b. Includes upgrades to Abrams tanks, Bradley fighting vehicles, M113-based vehicles, and M109 self-propelled howitzers to maintain a relatively constant average age for each fleet of vehicles after 2011.

c. Includes unattended ground sensors, unmanned aerial vehicles (Classes I, II, III, and IV), and the network.

d. Includes unattended ground sensors, unmanned aerial vehicles (Classes III and IV), the non-line-of-sight launch system, and the network.

e. Includes manned vehicles (command and control, medical, non-line-of-sight mortar, non-line-of-sight cannon, and infantry carrier) and 

the network.

Costs Included in the President's Budget 

FCS Program's Increment 1a 21 101 122

06 6

Continued purchases of FCS components, 

0 18 18

Additional upgrades to existing vehiclesb 2 15 17 ___ ___ ___

Total 23 139 162

FCS Componentsc 15 46 61

Upgrades to Current Systemsb 2 36 38 __ __ __

Total 17 82 99

FCS Componentsd 15 52 67

Upgrades to Current Systemsb 2 36 38 ___ ___ ___

Total 17 89 106

FCS Componentse 16 52 67

Upgrades to Current Systemsb 2 33 35 ___ ___ ____

Total 18 85 103

FCS Network 14 16 30

Upgrades to Current Systemsb 2 36 38 ___ ___ ___

Total 16 52 68

Research and Development Procurement Total Acquisition

Alternative 2. Long-Range Strikes

Alternative 3. New Vehicular Technology

Alternative 4. Existing-System Upgrades

Upgrades to existing vehicles

Further Costs as Estimated by CBO

2023 to 2025

Administration's Plan

Alternative 1. Collection and Sharing of Information
52 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Figure 4-1.

Annual Costs of the Administration’s Plan for the Future Combat Systems 

Program and Alternatives

(Billions of 2006 dollars)

Source: Congressional Budget Office.

Note: See Table 4-1 for a description of the alternatives. 

a. Based on documents submitted with the President’s 2007 budget, which includes $6 billion for upgrades to existing systems.

b. Includes upgrades to Abrams tanks, Bradley fighting vehicles, M113-based vehicles, and M109 howitzers to maintain a relatively constant 

average age for each fleet of vehicles after 2011.

combat brigade equipped with existing systems.4 Although, as with the current Raven system, the Army does 

not plan to dedicate trucks in a combat brigade specifically to transport the new smaller (Classes I and II) UAVs 

that would be assigned to the unit, the larger FCS 

Class III and Class IV UAVs would require considerable 

support. Specifically, each combat brigade is scheduled to 

include 50 small trucks (HMMWVs) and 12 large trucks 

(heavy expanded-mobility tactical trucks, or HEMTTs) 

to transport and support them. 

The additional vehicles needed to support the FCS UAVs 

would represent only a small increase in the weight of a 

heavy combat brigade. When added to the almost 

500 HMMWVs and 135 HEMTTs that are now part of 

a modular heavy brigade’s standard equipment, implementing this alternative might boost the total weight of 

such a brigade by roughly 500 tons (out of a total 25,000 

tons) and add 8,000 square feet to the brigade’s total coverage (approximately 320,000 square feet)—for relative 

increases of less than 3 percent.

Those small increases would have only a limited effect on 

the time needed to deploy heavy combat units from the 

continental United States to, for example, Djibouti. 

Moving a heavy brigade by air that was equipped with the 

enhanced sensors to be purchased under this alternative 

might take 10 more C-17 sorties—or an additional half 

day—to deploy to Djibouti, versus 23 days for a modular 

2005 2010 2015 2020 2025

0

2

4

6

8

10

12

14

Administration's Plan with

Additional Upgrades

Administration's Plan

Alternative 1 Alternative 2

Alternative 3

Alternative 4

a

b

4. Based on data from the Department of the Army and on the fielding plan included in Logistics Requirements and Readiness IPT, 

Materiel Fielding Sub-IPT, of the Boeing/SAIC Lead Systems 

Integrator, Future Combat Systems (FCS) Equipped Unit of Action 

(UA) Materiel Fielding Plan (MFP) to the UA Supportability Strategy (April 2005).
CHAPTER FOUR ALTERNATIVE APPROACHES TO MODERNIZING THE ARMY’S HEAVY FORCES 53

Table 4-4.

Time Needed to Deploy Equipment of 

Combat Units to East Africa

(Days)

Source: Congressional Budget Office based on data from the 

Department of the Army; Military Traffic Management 

Command Transportation Engineering Agency, Deployment Planning Guide: Transportation Assets Required for 

Deployment, MTMCTEA Pamphlet 700-5 (May 2001); and 

Department of the Air Force, Air Mobility Planning Factors, Pamphlet 10-1403 (December 18, 2003).

Note: Units would be moved from the continental United States. 

The data do not reflect the time needed to move sustaining 

units or supplies. See the text for more discussion of

alternatives.

a. The number of daily sorties constrained by the capacity of the 

airfield in East Africa, based on average airlift payloads per brigade of 60 tons for modular heavy units and 50 tons to 55 tons 

for units equipped with Future Combat Systems.

b. Based on documents submitted with the President’s 2007 

budget.

c. “Modular” refers to the Army’s ongoing modularity initiative, 

which seeks to make the service more flexible by changing its 

structure from one based on 18 divisions, several of unique 

design, to one based on 70 combat brigades, each one of only 

three designs. “Heavy” units are those equipped with armored 

vehicles.

d. Besides combat brigades, divisions include headquarters and 

other support units.

heavy brigade with current equipment. The small increase in the total number of vehicles would have no effect on the time to deploy by sea because additional vehicles and supporting gear could fit easily on the ships 

needed to move a modular heavy brigade with existing 

equipment overseas (see Table 4-4). For the same reason, 

the additional vehicles and gear would not affect the time 

needed to deploy a division-sized unit by sea.

Effect of Alternative 1 on the Current Active Fleet of 

Armored Combat Vehicles

This alternative would have little effect on the Army’s armored combat vehicle fleet. The composition and size of 

the fleet would remain unchanged: in 2040 as in 2011, 

the active fleet would comprise roughly 14,500 Abrams 

tanks, Bradley fighting vehicles, M113-based vehicles, 

and M109 howitzers (see Figure 4-2). In addition, the 

fleet’s average age would remain relatively constant at 

about 13 years, because the Army would invest $38 billion in upgrades from 2007 through 2025. By contrast, 

under the Administration’s plan, the average age of the 

active armored combat vehicle fleet would increase to 

roughly 16 years in 2020 and then eventually decline, as 

FCS vehicles replaced significant numbers of the older 

Abrams tanks, Bradley fighting vehicles, M113-based 

vehicles, and M109 howitzers.

Advantages and Disadvantages of Alternative 1

The major advantage of Alternative 1 is that under it, the 

Army would introduce new technology into its units 

more rapidly than under the Administration’s plan and at 

a lower cost. Because the Army would be developing and 

fielding some of the least technologically risky and least 

expensive of the FCS components (UAVs and unattended 

ground sensors), it could begin to introduce them into 

units in 2010 and purchase them at rates twice as high 

(three brigades’ worth of equipment per year) as the Administration’s planned annual purchases (1.5 brigades’ 

worth). As a result, by 2025, the Army under this alternative would have purchased enough Class III UAVs and 

network systems for 45 brigades—enough to equip all of 

the brigades in the Army’s active component plus three 

brigades in the National Guard, or enough to equip all of 

the Army’s heavy brigades (including five brigades’ worth 

of prepositioned stocks) plus 13 additional infantry or 

Stryker brigades. Costs under this alternative would be 

less than under the Administration’s plan, and the potential for cost growth would be half as great.

Modular heavy brigade with 

23 25

FCS-equipped brigade 18-20 25

23 25

24 25

24 25

135 27

115-130 27

140 27

140 27

145 27

3. New vehicular technology

Division-Sized Unitsd

Administration's Planb

3. New vehicular technology

Alternatives

1. Information collection and

sharing

2. Long-range strikes

Airlifta Sealift

Brigade-Sized Units

existing armored vehiclesc

Administration's Planb

Four modular heavy brigades with

existing armored vehiclesc

Four FCS-equipped brigades

Alternatives

1. Information collection and

2. Long-range strikes

sharing
54 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Figure 4-2.

Average Age and Composition of the Active Armored Combat Vehicle Fleet 

Under All Alternatives

Source: Congressional Budget Office.

Note: See Table 4-1 for a description of the alternatives. FCS = Future Combat Systems.

a. Reflects upgrades to existing systems based on documents submitted with the President’s 2007 budget.

Of course, this option would also suffer from disadvantages when compared with the Administration’s plan. Under Alternative 1, the Army would retain its current fleet 

of armored combat vehicles indefinitely. And even 

though it would invest $38 billion to upgrade them, by 

2040, some of those vehicles would have been in the 

Army’s inventory for almost 60 years. Another disadvantage is the technical risk involved in introducing network 

technology and associated communications links into 

older systems, such as the Abrams tanks and Bradley 

fighting vehicles. Previous attempts to upgrade the electronics suites in those vehicles, including communications and data-processing equipment, have met with 

some difficulties. In addition, because the Army would 

retain its older and more bulky armored vehicles, its 

heavy units would be slightly more difficult to deploy 

overseas than would units equipped solely with FCS vehicles—although, as mentioned earlier, that difference 

might not be practically significant.

Alternative 2. Develop and Procure 

FCS Components That Will Enhance the 

Army’s Long-Range Strike Capability

Under the second alternative to the current FCS program, the Army would retain components that would enhance its ability to carry out long-range strikes—specifically, the unattended ground sensors and the two longrange classes of UAVs (Classes III and IV) to detect and 

track targets, and the NLOS launch system and its associated missiles to attack those targets (see Table 4-5). All of 

the ground vehicles in the FCS program, both manned 

and unmanned, would be canceled under this alternative, 

as would the shorter-range UAVs (Classes I and II) and 

the intelligent munitions system. The Army would retain 

and upgrade its current fleet of armored combat vehicles; 

it would also develop and procure the FCS network to tie 

the sensors, launchers, and manned vehicles together.

Developing and fielding the NLOS launch system and 

long-range UAVs would extend a brigade’s ability to detect and strike targets at ranges that exceed its current 

2005 2010 2015 2020 2025 2030 2035 2040

0

5

10

15

20

25

30

35

0

3

6

9

12

15

18

21

Bradley

Fighting Vehicles

M113-Based Vehicles

M109

Self-Propelled

Howitzers

Fleet Average Age,

Administration's Plan Fleet Average Age,

Alternatives 1, 2, and 4

Abrams Tanks

Alternatives 1, 2, and 4

a

Thousands of Vehicles Average Age in Years

2005 2010 2015 2020 2025 2030 2035 2040

0

5

10

15

20

25

30

35

0

3

6

9

12

15

18

21

Alternative 3

Fleet Average Age,

Alternative 3

Fleet Average Age,

Administration 's Plan

M109

Self-Propelled

Howitzers

Manned FCS

Vehicles M113-Based Vehicles

Bradley

Fighting Vehicles

Abrams Tanks

a

Thousands of Vehicles Average Age in Years
CHAPTER FOUR ALTERNATIVE APPROACHES TO MODERNIZING THE ARMY’S HEAVY FORCES 55

Table 4-5.

Procurement of FCS Components Under the Administration’s Plan and

Under Alternative 2

Source: Congressional Budget Office.

Notes: Under Alternative 2, the Army would emphasize long-range strikes.

FCS = Future Combat Systems; UAV = unmanned aerial vehicles

a. A spiral is the Army’s term for a planned introduction (into units in the field or current systems or both) of technology developed as part 

of a larger program.

capability. (The A6 version of the M109 howitzer is the 

only existing system assigned to a modular brigade that 

can attack targets at distances of more than 20 km.) By 

using long-range Class IV UAVs to detect targets as far 

away as 75 km and the NLOS launch system to attack 

them at distances of up to 70 km, a brigade could defeat 

enemy forces before it was within range of their weapons.

Those same enemy targets could also be attacked by using 

the Air Force’s close-support aircraft or the Army’s helicopters, but in some circumstances, such support might 

not be available quickly enough. For example, bad 

weather might prevent aircraft from flying, or the Air 

Force might have higher priorities that would send its aircraft off to carry out a different mission. Similarly, helicopters might be kept on the ground because of unfavorable conditions, such as bad weather or sandstorms. (Or 

they, too, might be busy elsewhere with higher-priority 

missions.) Moreover, should a unit suddenly come under 

attack from long-range enemy artillery, there might not 

be time to order a retaliatory attack by fixed-wing aircraft 

or helicopters before the enemy escaped to a safe location. 

In such circumstances, on-the-spot targeting from UAVs 

and the rapid return of fire by quickly activated NLOS 

launch systems would offer capabilities that today’s brigades lack.

Costs and Procurement Schedule Under 

Alternative 2

Under this alternative, as under the previous one, the 

Army would develop and procure some of the least technologically challenging and least expensive FCS components. As a result, rates of procurement could be higher 

than those planned by the Administration, but the ensuing costs would be lower. Specifically, starting in 2016 

and continuing through 2025, the Army each year under 

this alternative would buy three brigades’ worth of unattended ground sensors, Class III and IV UAVs, NLOS 

launch systems, and network hardware. Procurement of 

the ground sensors and launch systems, which are the 

most technologically mature of the FCS components to 

be bought under this alternative, would start in 2008;5

Spirala Fielding to Units Starts Administration's Plan Alternative 2

1 2010 Non-line-of-sight launch system Non-line-of-sight launch system

Unattended ground sensors Unattended ground sensors

Intelligent munitions system Spiral 1 network

Spiral 1 network

2 2012 UAV Class III UAV Class III

Spiral 2 network improvements Spiral 2 network improvements

3 2014 Unmanned ground vehicles UAV Class IV

Spiral 3 network improvements

4 2016 UAV Classes I, II, and IV None

Manned vehicles

Complete network

Components To Be Procured

5. Procurement of portions of the network associated with the unattended ground sensors and NLOS launch systems would also 

begin in 2008.
56 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

procurement of the Class III UAV, in 2010; and that of 

the Class IV UAV, in 2012. All told, from 2007 through 

2025, the Army would buy 45 brigades’ worth of unattended ground sensors, NLOS launch systems, and network hardware; 39 brigades’ worth of Class III UAVs; 

and 33 brigades’ worth of Class IV UAVs. Total procurement costs for those systems would be $52 billion; the 

associated costs to develop them would be $15 billion 

over the same period.

This alternative, like Alternative 1, would require the retention and upgrading of the armored combat vehicles 

currently needed to equip and support the modular 

Army. Costs for those vehicles over the 2007–2025 period would be identical to those under Alternative 1: 

$2 billion for research and development and $36 billion 

for procurement. In total, costs under Alternative 2 during that period would equal $106 billion—$7 billion 

more than under the previous alternative but considerably less than under the Administration’s plan (see

Table 4-3 on page 51). Annual costs would be roughly 

$6 billion to $7 billion (see Figure 4-1 on page 52). As 

was the case under the previous alternative, the potential 

for cost growth would be much lower (by roughly onethird) for the FCS components included under this alternative than it would be for those associated with the FCS 

program as a whole, which on the basis of past experience 

could see a rise in costs of about 60 percent.

Effect of Alternative 2 on Deployment of Army Units

Carrying out this alternative could add some weight to 

the equipment deployed with the Army’s brigades, but it 

would not significantly affect the time required for deployment. As was the case under the previous alternative, 

equipping Army brigades with dozens of relatively large 

UAVs would mean adding more than 60 trucks to a brigade’s total inventory. Under this alternative, each brigade 

would also be equipped with 60 NLOS launch systems—

and the 30 large trucks and four HMMWVs needed to 

support them.

In total, the Army under this option might add about 

100 vehicles to each brigade’s inventory, which could 

translate into 1,100 tons of additional weight and 16,000 

square feet of additional coverage. Those increases in turn 

would represent about 20 additional C-17 sorties and an 

increase of one day in the time needed to deploy by air; 

for deployment by sea, they would represent about 

10 percent of the deck space on a fast sealift ship or 5 percent of that on a large medium-speed roll-on/roll-off ship 

but no increase in the time needed to deploy a brigade 

(see Table 4-4 on page 53). Nor would the Army under 

this alternative find that it needed more time to deploy a 

a division (composed of four modular heavy brigades 

equipped with Class III and IV UAVs and NLOS launch 

systems) by sea compared with the time needed to deploy 

the same division equipped with existing systems.

Effect of Alternative 2 on the Current Active Fleet of 

Armored Combat Vehicles

Under this option, the Army’s active fleet of armored vehicles would be only minimally affected. Over the 

19 years from 2007 through 2025, the Army would invest $38 billion to maintain the average age of its approximately 14,500 armored combat vehicles at a constant 

13 years—which is significantly lower than the average 

age of the fleet that would result under the Administration’s plan (see Figure 4-2 on page 54).

Advantages and Disadvantages of Alternative 2

The Army under this option would increase the firepower 

of its brigades sooner than it would under the Administration’s plan, and it would do so at a lower cost. By canceling parts of the FCS program, primarily the high-cost 

ground vehicles, the Army would save $73 billion from 

2007 through 2025 and would be able to buy enough 

high-volume missile launchers to equip 45 brigades—an 

increase of 21 brigades over what it could buy under the 

Administration’s plan during the same period.6 Moreover, 

under this alternative, the Army’s R&D efforts would be 

less technologically risky and the systems it developed 

and procured would have a lower potential for cost 

growth. Finally, by investing $38 billion of the savings realized by canceling portions of the FCS program in upgrades to its existing armored vehicles, the Army could 

maintain the age of the active fleet at a constant 13 years.

On at least two counts, however, this alternative would 

not compare favorably with the Administration’s plan. 

First, under this option, the Army’s current fleet of armored combat vehicles would be retained indefinitely. 

Given that those vehicles were originally designed in the 

1970s or earlier, it might be difficult to integrate them—

using the FCS network—with the FCS sensors and the 

NLOS launch systems. Second, the weight and bulk of 

6. That comparison incorporates the assumption that the Administration would continue to purchase 1.5 brigades’ worth of FCS 

components annually through 2025.
CHAPTER FOUR ALTERNATIVE APPROACHES TO MODERNIZING THE ARMY’S HEAVY FORCES 57

the Army’s combat brigades would increase because of the 

additional equipment required under this alternative, 

with the result that an extra day might be added to the 

time needed to deploy a brigade by air.

Alternative 3. Emphasize Investment in 

New Manned Combat Vehicles

Development and procurement of new vehicles to replace 

many of the Army’s oldest combat vehicles would be 

the main emphasis of Alternative 3. The new vehicles 

would include most, but not all, of those currently under 

development in the FCS program—specifically, the 

FCS command-and-control vehicle, mortar carrier 

(NLOS-M), medical evacuation and treatment vehicle, 

infantry carrier, and howitzer (NLOS-C). When fielded 

in large enough numbers, those vehicles could eventually 

replace all of the M113-based vehicles and M109 howitzers now assigned to heavy combat brigades. The FCS vehicles would address at least some of the problems (such 

as the inability of the M109 howitzers to keep up with 

the newer Abrams tanks and Bradley fighting vehicles) 

that the Army has said are associated with keeping those 

older vehicles in its combat units.

Under this alternative, the Army would retain its Abrams 

tanks and Bradley fighting vehicles and upgrade them 

rather than replace them with vehicles developed in the 

FCS program. It would also upgrade M113-based vehicles and M109 howitzers assigned to units outside of 

combat brigades until those systems could be replaced by 

FCS vehicles. In addition, the Army would continue to 

develop the FCS network and install appropriate hardware in the Abrams tanks and Bradley fighting vehicles 

during upgrades so that they, too, could be integrated 

into the network (see Table 4-6).

By developing and fielding new vehicles to replace those 

that have, in one form or another, been in the Army’s inventory for more than 40 years, this alternative would 

greatly enhance the lethality and technological sophistication of a large portion of the armored combat vehicles in 

the Army’s brigades. The FCS vehicles that would replace 

the M113-based vehicles and M109 howitzers in a heavy 

brigade would be equipped with better armaments and 

electronic gear. For example, the NLOS-C, as currently 

envisioned, would be capable of higher rates of fire than 

the A6 version of the M109 howitzer and, because of its 

improved fire-control systems, would be more accurate in 

its delivery of artillery rounds. Likewise, the NLOS-M, 

according to current designs, would be a more lethal 

weapon than the mortar on the M113-based vehicle, capable of reacting more quickly to threats and firing more 

mortar rounds per minute.

In addition to the greater lethality that the Army would 

gain under this alternative, its fielding of the sophisticated medical evacuation vehicle that is part of the FCS 

program should enhance the survivability of soldiers who 

are wounded on the battlefield.

Under this alternative, the Army would cancel several 

portions of the FCS program and reduce others. Specifically, it would:

B Cancel all programs to develop and procure unmanned systems, including all four classes of UAVs, all 

unmanned ground vehicles, the NLOS launch system, 

the unattended ground sensors, and the intelligent 

munitions system;

B Cancel manned ground vehicles (the mounted combat 

system and the reconnaissance and surveillance vehicle) that are slated to perform missions currently assigned to the Abrams tanks and Bradley cavalry 

fighting vehicles;

B Reduce by about 75 percent the number of FCS infantry carrier vehicles purchased per brigade to reflect 

the fact that the Bradley infantry fighting vehicles will 

be retained in the heavy brigades; 

B Cancel the planned programs for the FCS maintenance and recovery vehicle (because the Abrams tanks 

would be retained and thus so would the current M88 

heavy recovery vehicle); and

B Scale back procurement of the FCS network, a version 

of which would be developed and fielded under this 

alternative, to reflect the smaller number of systems 

that it would have to support in each brigade. 

Because the Army under this alternative would retain the 

Abrams tanks and Bradley fighting vehicles indefinitely, it 

would upgrade them sufficiently to prevent their average 

age from increasing after 2011. However, because the 

Army would focus on accelerating the fielding of FCS 

components to replace the M113-based vehicles and 

M109 howitzers currently in its combat brigades, it 
58 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Table 4-6.

Procurement of FCS Components Under the Administration’s Plan and

Under Alternative 3

Source: Congressional Budget Office.

Notes: Under Alternative 3, the Army would emphasize new vehicular technology.

FCS = Future Combat Systems; UAV = unmanned aerial vehicles.

a. A spiral is the Army’s term for a planned introduction (into units in the field or current systems or both) of technology developed as part 

of a larger program.

b. Under Alternative 3, the Army would buy roughly 25 percent of the infantry carrier vehicles included in the Administration’s plan.

would maintain and upgrade only those vehicles that 

were retained (until they could be replaced) in units outside of the combat brigades. It would not invest funds in 

upgrading M113-based and M109 vehicles assigned to 

combat brigades—because those vehicles would be the 

first to be replaced by FCS components. 

Costs and Procurement Schedule Under 

Alternative 3

The cost of implementing this alternative would be similar to that of carrying out Alternatives 1 and 2, requiring 

a total investment of $103 billion from 2007 through 

2025. Of that total, $67 billion would be needed to develop and procure the five variants of manned FCS vehicles. Because the Army under this alternative would pursue only a subset of the FCS components included under 

the Administration’s plan, it would be able to purchase 

two brigades’ worth of the manned FCS vehicles each 

year beginning in 2015, for a total of 23 brigades’ worth 

by 2025. The cost of upgrading the armored combat vehicles from the current fleet that would be retained under 

this alternative would total $35 billion from 2007 

through 2025, the preponderance of which—$33 billion—would go toward procurement (see Table 4-3 on 

page 51).

Because the manned vehicles are the most technically 

challenging of the 18 FCS components, their developSpirala Fielding to Units Starts Administration's Plan Alternative 3

1 2010 Non-line-of-sight launch system Spiral 1 network

Unattended ground sensors

Intelligent munitions system

Spiral 1 network

2 2012 UAV Class III Spiral 2 network improvements

Spiral 2 network improvements

3 2014 Unmanned ground vehicles None

Spiral 3 network improvements

4 2016 Manned vehicles Manned vehicles

Medical Medical 

Infantry carrier Infantry carrierb

Non-line-of-sight mortar Non-line-of-sight mortar

Non-line-of-sight cannon Non-line-of-sight cannon

Command and control Command and control

Mounted combat system

Recovery and maintenance

Reconnaissance and surveillance

UAV Classes I, II, and IV

Complete Network

Components To Be Procured
CHAPTER FOUR ALTERNATIVE APPROACHES TO MODERNIZING THE ARMY’S HEAVY FORCES 59

ment would take the longest. Consequently, under this 

alternative, the Army would not begin to purchase those 

systems until 2014. The annual funding required to implement this alternative would thus be less than that 

for the previous two alternatives and for the Administration’s plan until 2015 (see Figure 4-1 on page 52). Thereafter, annual funding would be slightly higher, at about 

$6.5 billion, than under the previous alternatives but still 

significantly below that required under the Administration’s plan. Similarly, because the Army would be developing and procuring ground vehicles—the systems whose 

costs in the past have exceeded estimates by the greatest 

degree—the potential for cost growth under Alternative 3, at 55 percent, would be higher than under Alternatives 1 and 2 but lower than under the Administration’s 

plan.

Effect of Alternative 3 on Deployment of Army Units

This alternative would have a slight negative effect on the 

speed of units’ deployment because most of the vehicles 

being replaced would weigh less than their replacements. 

Under this approach, the Army, on average, would replace slightly less than half of the armored vehicles in a 

heavy brigade with manned FCS vehicles, but most of the 

vehicles that would be displaced—120 out of 136—

would be based on the M113 chassis and weigh less than 

the FCS replacements. That would hold true whether the 

ultimate weight of the FCS vehicles was 24 tons (the design threshold) or 19 tons (the program’s original goal) 

because M113-based vehicles weigh from 12 tons to 

14 tons, or considerably less than any potential manned 

FCS vehicle. As a result, the combined weight of the 

combat vehicles in a brigade under this alternative could 

be as much as 1,400 tons more than that of the combat 

vehicles in a modular heavy brigade equipped with existing armored vehicles.

An argument might be made that the FCS-equipped brigade as a whole would weigh no more than one of today’s 

modular brigades because the manned FCS components 

would require fewer support vehicles, such as trucks. But 

given the equipment that is currently scheduled to be assigned to a brigade equipped entirely with FCS components, a brigade equipped as Alternative 3 specifies would 

still appear to weigh more than the modular brigade it 

was meant to replace.7

The extra weight of the equipment assigned to heavy 

combat brigades under this alternative might slightly increase the time to deploy a brigade by air, but the change 

would be insignificant. Deploying a brigade equipped 

with a combination of FCS and current armored vehicles 

to Djibouti by air would take 24 days rather than 

23 days—but the time it would take to deploy by sea 

would remain unchanged, at 25 days (see Table 4-4 on 

page 53). The time to deploy by sea a division-sized 

heavy unit equipped with the FCS components included 

under this alternative would also remain at 27 days. (Deploying a division-sized heavy unit by air is impractical; 

however, to complete the comparisons, it would take 

roughly 145 days, in CBO’s estimation, to deploy a division with four heavy brigades equipped with FCS components as laid out under this alternative, compared with 

135 days for a division with four modular heavy brigades 

equipped with existing vehicles.)

Effect of Alternative 3 on the Armored Combat Fleet

Under this alternative, the Army would introduce new armored combat vehicles faster than it would under the Administration’s plan, which would keep the average age of 

the active fleet below 15 years through 2040 (see Figure 

4-2 on page 54). If this alternative was carried out, the 

Army would have bought and fielded enough FCS vehicles by 2029 to replace all of the M113-based vehicles 

and M109 howitzers in the heavy combat brigades. Until 

then, however, a sizable number of M113-based vehicles 

would be retained, and their average age would exceed 

15 years through 2026. (In 2020, the 5,600 M113-based 

vehicles in the inventory would have an average age of 

18 years.) As a consequence, the average age of the active 

fleet of armored vehicles under this alternative would 

peak at slightly more than 14 years in 2016 before starting to decline—an improvement over the fleet’s condition under the Administration’s plan.

Advantages and Disadvantages of Alternative 3

Alternative 3 is unique among the approaches CBO considered in that it would introduce new vehicular technology into the Army’s forces, thus offering the advantage 

that the service could retire some of its oldest armored vehicles earlier than under any of the other alternatives. The 

option’s costs are on a par with those of Alternatives 1 

7. The FCS design calls for 550 trucks, compared with 880 for a 

heavy brigade equipped with today’s armored combat vehicles. 

However, the FCS-equipped brigade would have about 15 percent 

more large trucks—at 20 tons each—than a modular heavy brigade would have. Consequently, the weight of the supporting 

vehicles for the two types of brigades might be very similar.
60 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

and 2; like them, it is considerably less expensive than the 

Administration’s plan.

Alternative 3, however, also shares some of the disadvantages of those previous options. The Army under this alternative would retain its fleets of Abrams tanks and 

Bradley fighting vehicles indefinitely and would have to 

incorporate the technology associated with the FCS network into those vehicles. In addition, the risk of cost 

growth associated with this alternative, although lower 

than under the Administration’s plan, is higher—at 

55 percent—than under the other alternatives.

Alternative 4. Develop a Scaled-Down 

FCS Network and Integrate It with 

Existing Systems

The last alternative that CBO examined would preserve 

only that part of the FCS program involved in developing 

and supporting the network. The new capability—under 

this alternative, a scaled-down version of the network currently envisioned for the FCS program—would then be 

integrated into existing armored vehicles, which would be 

upgraded to keep them current. All other portions of the 

FCS program would be canceled.

This alternative has the appeal of taking an evolutionary 

approach to improving the capability of the armored vehicles in the Army’s combat brigades rather than providing a wholesale makeover based on unproven technology. 

By introducing into existing vehicles those portions of the 

networking improvements that are developed—and 

proved effective—in the FCS program, the Army under 

this alternative could take advantage of advances in technology and information sharing yet retain the best features of its current fleet (in particular, the high degree of 

survivability of the Abrams tank). Those features are not 

insignificant: through numerous upgrades and the introduction of new technology as it has evolved, the Army’s 

armored combat vehicles have proved to be among the 

most capable—if not the most capable—weapon systems 

in the world.

Costs and Procurement Schedule Under

Alternative 4

Because the Army would purchase the least amount of 

hardware under this alternative, the option would be the 

least expensive of the four CBO considered. Its associated 

total costs of $68 billion would cover developing and 

purchasing the hardware for the FCS network ($30 billion) and upgrading existing armored vehicles ($38 billion; see Table 4-3 on page 51). This alternative would 

also require the smallest amount of annual funding—

roughly $3 billion in 2018 and thereafter—despite the 

fact that three brigades’ worth of FCS network hardware 

would be purchased each year starting in 2012 (see Figure 

4-1 on page 52). At that rate of procurement, the Army 

by 2025 would have purchased equipment for 45 brigades—enough for all of its heavy brigades (including 

National Guard units), five prepositioned brigades, and 

13 additional combat brigades, either infantry or Stryker. 

None of the 18 FCS components would be developed or 

purchased under this alternative. Nevertheless, growth in 

costs of about 40 percent would still be possible, based on 

historical experience, because more than half of the alternative’s costs would be associated with upgrading existing 

ground vehicles.

Effect of Alternative 4 on Deployment of Army Units

Because the Army under this alternative would not add 

any new vehicles to existing combat brigades or replace 

existing systems with new ones, the ability of its units to 

deploy overseas would not be affected. The time needed 

to deploy a heavy brigade to Djibouti by air or by sea 

would be the same as it is for today’s modular heavy brigades—23 days and 25 days, respectively. Similarly, there 

would be no change in the time needed to move a division-sized unit composed of four modular heavy brigades 

to Djibouti by sea—which would remain at 27 days.

Effect of Alternative 4 on the Army’s Fleet of 

Armored Vehicles

As it would under Alternatives 1 and 2, the Army under 

Alternative 4 would retain its existing armored combat 

vehicles indefinitely. Through upgrades, the average age 

of the active fleet of roughly 14,500 vehicles could be 

maintained at about 13 years through 2040. And by 

2021, all of those vehicles in heavy brigades could be 

retrofitted with FCS hardware that would allow them to 

be integrated into the network—if the Army chose to 

modernize its heavy brigades first.8 In any case, the 

Army’s armored combat fleet in 2040 under this alterna8. Alternatively, with the 45 brigades’ worth of network hardware 

purchased through 2025, the Army could equip all of the brigades 

in its active component first, followed by three of the prepositioned equipment sets. That approach would leave two prepositioned sets and all 28 National Guard brigades outside the 

network.
CHAPTER FOUR ALTERNATIVE APPROACHES TO MODERNIZING THE ARMY’S HEAVY FORCES 61

tive would comprise the same vehicles that it did in 2011 

(see Figure 4-2 on page 54). 

Advantages and Disadvantages of Alternative 4

The greatest advantage of this alternative—the least expensive of the options that CBO examined—is its relatively low estimated cost of $68 billion from 2007 

through 2025. Of course, because it would invest so little 

in new technologies and equipment, it would also offer 

the Army the least in terms of innovation. Under this alternative, the service would maintain the same fleet of armored vehicles that it has had for more than 20 years, 

some of which—notably the M113-based vehicles—have 

been in service since the Korean War. Although connected by a new network and upgraded to keep them in 

working condition, those vehicles will offer nothing new 

to the Army’s combat arsenal.

APPENDIX

A

A Description and History of the

Army’s Current Armored Vehicles

This appendix describes the four types of armored 

vehicles that make up most of the Army’s armored fleet: 

the M1 Abrams tank, the M2 and M3 Bradley fighting 

vehicles, vehicles based on the M113 armored personnel 

carrier, and the M109 self-propelled howitzer. The discussion also touches on the evolution of each of the 

Army’s armored vehicle fleets since the vehicles were first 

introduced into the Army’s inventory.

Abrams Tanks 

The Abrams, or M1, tank was developed in the 1970s 

and initially produced in 1980 with a 105-millimeter 

(mm) main gun capable of attacking targets up to 3 kilometers (km) away. The primary purpose of the Abrams 

when it was first introduced was to be able to win in any 

battle with Soviet tanks. During the 1980s and 1990s, 

the tank’s design underwent changes that were designed 

to counter the increased capabilities of tanks fielded by 

the Soviets. Thus, later models of the Abrams tank had a 

larger 120-mm main gun that was capable of firing shells 

at higher speeds than the original 105-mm gun. This enabled the later models of the Abrams to attack targets at 

greater ranges or penetrate thicker armor at the same distance. In addition, the Abrams was given improved 

heavier armor that enhanced its ability to stop enemy 

tank rounds (see Table A-1 on page 67). The most recent 

modifications, known as the System Enhancement Program (SEP) and the Abrams Integrated Management program, were introduced in 1999 and 2000 and included 

improvements in armor, targeting, communications, and 

navigation systems.

Not surprisingly, larger guns, heavier armor, and more 

sensors have added weight to the tank. As a result, the latest version of the Abrams, the M1A2 SEP, weighs more 

than 70 tons, compared with the basic M1 model, which 

weighed roughly 10 tons less (see Table A-1 on page 67).

At the end of 2003, the Army’s Abrams fleet of approximately 5,850 tanks contained a mix of models, with the 

M1A1 accounting for the vast majority (see Figure A-1). 

And even though the last new tank was delivered to the

Figure A-1.

Average Age and Composition of the 

Army’s A1 Abrams Tank Fleet

(Thousands of vehicles) (Average age in years)

Source: Congressional Budget Office based on data from the 

Department of the Army.

Notes: The last data points are for the end of 2003.

IP = Improved; AIM = Abrams Integrated Management 

program; SEP = System Enhancement Program.

1980 1983 1986 1989 1992 1995 1998 2001

0

2

4

6

8

10

0

3

6

9

12

15

Basic, IP

A1

A1 AIM

A2 SEP

A2

Average Age
64 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Figure A-2.

Average Age and Composition of the 

Army’s M2/M3 Bradley Fighting 

Vehicle Fleet

(Thousands of vehicles) (Average age in years)

Source: Congressional Budget Office based on data from the 

Department of the Army.

Notes: The last data points are for the end of 2003.

ODS = Operation Desert Storm.

Army in 1993, constant upgrades of existing models and 

retirement of some older models kept the average age of 

the tank fleet below 13 years through the end of 2003.

Bradley Fighting Vehicles 

The Bradley fighting vehicle was developed in two versions—the infantry (M2) fighting vehicle and the cavalry 

(M3) fighting vehicle; both are equipped with a 25-mm 

gun; tube-launched, optically tracked, wire-guided 

(TOW) antitank missiles; and a 7.62-mm machine gun. 

The differences between the two versions are minor; because of the kinds of missions it undertakes, the cavalry 

version carries more radios and missile rounds than does 

the infantry version, which can carry more soldiers (in 

addition to the crew of three, six passengers versus two 

for the cavalry fighting vehicle).

Both versions were introduced in 1981; by the mid1990s, the Army had purchased roughly 6,700 Bradley 

fighting vehicles, two-thirds of them in the infantry (M2) 

configuration and the remainder in the cavalry (M3) configuration. In terms of the original models of those vehicles (most have been upgraded since they were purchased), the breakdown is as follows: 

B The first 2,300 Bradleys (M2 and M3 combined) purchased from 1981 to 1984 were in the A0, or original, 

configuration; 

B About 1,400 Bradleys built from 1985 to 1988 were 

in the A1 design, which incorporated an improved 

version of the TOW missile system; and

B The final 3,000 or so Bradleys purchased new were A2 

models that included enhanced protection of the crew 

and passengers, such as additional appliqué steel armor to defend against larger projectiles and an internal 

liner to prevent hull fragments—or spall—from injuring soldiers inside the vehicle (see Table A-2 on 

page 68).

Since 1995, the Army has produced very few new Bradley 

fighting vehicles but instead has been upgrading existing 

models (see Figure A-2). By 2003, almost 1,700 older 

versions had been converted to the A2 Operation Desert 

Storm (A2 ODS) configuration, which features an improved rangefinder and navigation system. The most recent versions of the Bradley fighting vehicle—the M2A3 

and M3A3—were introduced in 1999 and include digital 

communications, improved viewers and sensors, an improved turret drive, and survivability enhancements, such 

as titanium armor for the roof. As a result of the upgrades 

that many Bradleys have undergone, the average age of 

the fleet is considerably lower than the vehicles’ original 

production dates might indicate. (Those dates range from 

1980 to 1994.) Indeed, the modernization of more than 

2,500 Bradleys since 1995 resulted in an average age for 

the fleet of 10 years at the end of 2003—rather than an 

average age closer to 20 years, which would have been expected in the absence of the upgrades (see Figure A-2).

As with the Abrams tank, improvements in the Bradley 

fighting vehicle’s capabilities have made subsequent models heavier. The original A0 model weighed 25 tons, but 

the additional equipment and improved armor of the 

later A2 and A3 models added 7 tons and 8 tons, respectively, to the vehicles’ total weight. The additional weight 

reduced the Bradley’s fuel efficiency slightly from 1.7 

miles per gallon (mpg) for the earliest models to 1.5 mpg 

and 1.4 mpg for the A2 and A3 models. 

1980 1983 1986 1989 1992 1995 1998 2001

0

2

4

6

8

10

0

3

6

9

12

15

A0

A2 A1

Average Age

A2 ODS A3
APPENDIX A A DESCRIPTION AND HISTORY OF THE ARMY’S CURRENT ARMORED VEHICLES 65

Figure A-3.

Average Age and Composition of the 

Army’s M113-Based Vehicle Fleet

(Thousands of vehicles) (Average age in years)

Source: Congressional Budget Office based on data from the 

Department of the Army.

Note: The last data points are for the end of 2003.

The M113 Family of Vehicles

The Army began developing the original M113 in 1956 

to provide armored and infantry units with a lightweight 

multipurpose personnel carrier. Designed from the beginning with certain features (for example, to be amphibious 

and capable of being dropped into a theater by air) but 

with the ability to adapt to multiple functions, the M113 

has been fielded in various configurations, including 

smoke generator, mortar carrier, cargo carrier, command 

post, antitank missile carrier, and personnel carrier. The 

most numerous of the Army’s armored vehicles, with 

roughly 18,000 in service at the end of 2003, the M113 

is also the Army’s only armored vehicle that weighs less 

than 20 tons or that has a fuel efficiency that exceeds 2 

mpg. Even the largest model of the M113 vehicle is relatively compact and—at 17 feet long, 9 feet wide, and 

8 feet tall—is considerably smaller than either the 

Abrams tank or Bradley fighting vehicles.

Since it was first developed, the M113 vehicle has been 

modified several times. The first enhancement—the 

switch from a gasoline engine in the original M113 

model to a diesel engine in the M113A1 and subsequent 

models—came in the 1960s, shortly after the vehicle was 

first fielded. Then, after producing 18,000 A0 and A1 

models in the 1960s and 1970s, the Army embarked on a 

product improvement program in the 1980s and 1990s 

that resulted in a totally revamped fleet. The M113A2, 

introduced in 1979, incorporated enhanced cooling for 

the engine and improved suspension (see Table A-3 on 

page 69); that model accounted for roughly two-thirds of 

the M113 fleet at the end of 2003 (see Figure A-3). The 

latest variant, the M113A3, was first produced in the 

mid-1980s and includes an improved transmission and 

drive train, simpler driver controls, and an antispall liner. 

Although no new M113A3s have been produced since 

1992, by 2003, the Army had converted more than 2,000 

older model M113s to the A3 configuration.

The continual upgrading of existing M113s since the late 

1970s kept the average age of the fleet below 10 years 

through 1998 (see Figure A-3). However, the rate of conversions since 1995 has not been sufficient to retard the 

aging of the fleet, even though large numbers of older vehicles have been retired. As a result, the average age of the 

roughly 18,000 M113-based vehicles in the Army’s inventory at the end of 2003 was slightly greater than 

13 years.

M109 Self-Propelled Howitzer 

The M109 self-propelled howitzer has been in the Army’s 

inventory of armored vehicles since 1962. Its 155-mm 

cannon provides supporting fire to the Army’s combat 

units and can shell targets at a distance of 30 km. The latest model of the howitzer weighs more than 30 tons, is 

the largest of the Army’s current fleet of armored vehicles 

(32 feet long by 10 feet wide by 11 feet high), and has a 

fuel efficiency of less than 2 mpg (see Table A-4 on 

page 70).

Like the Army’s other armored vehicles that have been in 

service since the 1960s, the M109 has undergone several 

upgrades, although all but the most recent have not involved significant modifications. Compared with the 

original version, subsequent models (A2, A3, A4, and A5) 

have mounted 155-mm cannons with longer barrels and 

greater ranges. Additional improvements include air purifiers and heaters for the crew’s protection and comfort, an 

external rack at the back of the turret for carrying equipment, and increased reliability.

1980 1983 1986 1989 1992 1995 1998 2001

0

5

10

15

20

25

30

35

0

2

4

6

8

10

12

14

Average Age

A1

A0

A2

A3
66 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Figure A-4.

Average Age and Composition of the 

Army’s Fleet of M109 Self-Propelled 

Howitzers

(Thousands of vehicles) (Average age in years)

Source: Congressional Budget Office based on data from the 

Department of the Army.

Note: The last data points are for the end of 2003.

As part of a major upgrade program, the Army began 

converting existing howitzers to the A6, or Paladin, 

model in 1991 and by the end of 2003 had a total of 

975 M109A6s in its inventory. The improvements provided by that upgrade included supplemental armor and 

a spall liner; a fire-suppression system; better engine cooling; enhanced suspension, hydraulic, and electrical systems; a new fire-control computer; and a new cannon 

mount. The extensive modifications involved in the Paladin upgrades—which effectively resulted in a new howitzer—combined with the decommissioning of older models reduced the average age of the M109 fleet to roughly 

nine years in 1999. Subsequently, however, the average 

age increased; by the end of 2003, it had reached 11 years 

(see Figure A-4).

1980 1983 1986 1989 1992 1995 1998 2001

0

1

2

3

4

5

0

5

10

15

20

25

Average Age

A4/A5 A6
APPENDIX A A DESCRIPTION AND HISTORY OF THE ARMY’S CURRENT ARMORED VEHICLES 67

Table A-1.

Characteristics of Models of the Abrams (M1) Tank

Source: Congressional Budget Office based on its February 1993 report Alternatives for the U.S. Tank Industrial Base; and Gary W. Cooke, 

“Gary's Combat Vehicle Reference Guide,” available at www.inetres.com/gp/military/cv/index.html.

Notes: IP = Improved; AIM = Abrams Integrated Management program; SEP = System Enhancement Program; mpg = miles per 

gallon; mm = millimeters; n.a. = not applicable; NBC = nuclear, biological, chemical; FLIR = forward-looking infrared; GPS = global 

positioning system; SINCGARS = single-channel ground and airborne radio system.

Basic

Date of Introduction 1981

Combat Weight (Tons) 60

Range (Miles) 280

Fuel 

504

0.6

Size of Main Gun (mm) 105

(Length x width x height,

in feet) 32 x 12 x 9

Improvements Over

Previous Model

Armor n.a.

Other n.a. n.a.

commander's

 FLIR for

Integrated GPS

independent

thermal viewer

120

Third-generation 

Second-generation

depleteduranium 

armor

504

0.5

120

32 x 12 x 9

A2 SEP

1999

70+

265

32 x 12 x 9

Second-generation 

Digital electronics Commander's 

depleted-uranium 

armor

A2

1991

70

265

32 x 12 x 9

n.a.

Improved 

275

504

120

275

Improved 

IP

Model

A1

1985

61

310

504

0.6

1985

67

A1 AIM

2000

68

504

120

32 x 12 x 9

Heavy armor 

504

0.5

Capacity (Gallons)

32 x 12 x 9

Efficiency (mpg) 0.5 0.5

Vehicle Dimensions 

105

composite 

armor

added to hull

and turret

SINCGARS radio

protective system

suspension independent 

thermal viewer

Digital electronics

Active NBC
68 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Table A-2.

Characteristics of Models of the Bradley Infantry (M2) and Cavalry (M3)

Fighting Vehicles

Source: Congressional Budget Office based on data from the Department of the Army; Gary W. Cooke, “Gary’s Combat Vehicle Reference 

Guide,” available at www.inetres.com/gp/military/cv/index.html; and Christopher Foss, ed., Jane’s Armour and Artillery, 2003–

2004 (Alexandria, Va.: Jane’s Information Group, 2003).

Note: ODS = Operation Desert Storm; mpg = miles per gallon; n.a. = not applicable; TOW = tube-launched, optically tracked, wire-guided; 

GPS = global positioning system; NBC = nuclear, biological, chemical; FLIR = forward-looking infrared. 

a. The liner protects vehicle occupants from hull fragments.

A0

Date of Introduction 1981

Combat Weight (Tons) 25

Range (Miles) 300

175

1.7

Dimensions (Length x width x

22 x 11 x 10

Armor n.a.

Other n.a.

and driver's

vision enhancer

Digital

communications

NBC filter system

engine

A2

Improved TOW

A1

22 x 11 x 10

n.a.

300

175

1.7

22 x 11 x 10

Laser rangefinder

n.a.

22 x 11 x 10

Additional appliqué

More powerful

A2 ODS A3

1986

25

1997

32

1999

33

1988

Model

250

175

1.4

265

1.5 1.5

32

265

175

Fuel

Titanium roof armor

Second22 x 11 x 12

175

Improvements Over Previous 

Capacity (Gallons)

Efficiency (mpg)

height, in feet)

independent viewer

Model

armor

Improved suspension

generation FLIR

Antispall linera

GPS navigation

for commander's

missile system
APPENDIX A A DESCRIPTION AND HISTORY OF THE ARMY’S CURRENT ARMORED VEHICLES 69

Table A-3.

Characteristics of Models of the M113-Based Family of Vehicles

Source: Congressional Budget Office based on data from the Department of the Army; Gary W. Cooke, “Gary’s Combat Vehicle Reference 

Guide,” available at www.inetres.com/gp/military/cv/index.html; and Christopher Foss, ed., Jane’s Armour and Artillery, 1979-

1980 (New York: Wyatt Publishing, 1979).

Note: mpg = miles per gallon; n.a. = not applicable.

a. The liner protects vehicle occupants from hull fragments.

A0 A1 A2

Date of Introduction 1961 1964 1979

Combat Weight (Tons) 12 12 12

Range (Miles) 300 300 300

95 95 95

3.2 3.2 3.2

Dimensions (Length x width x 16 x 9 x 8 16 x 9 x 8 16 x 9 x 8

height, in feet)

Improvements Over Previous Model

n.a. n.a. n.a.

n.a. Diesel engine Enhanced engine cooling

Improved suspension

Antispall linera

steering and brake

controls

Armor

Other

armor

diesel engine

Provisions for bolt-on

Greater horsepower 

Fuel

Capacity (Gallons)

Efficiency (mpg)

Model

300

95

3.2

17 x 9 x 8

Automotive-type

A3

1986

14

Improved 

transmission
70 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Table A-4.

Characteristics of Models of the M109 Self-Propelled Howitzer

Source: Congressional Budget Office based on data from the Department of the Army and Gary W. Cooke, “Gary’s Combat Vehicle Reference 

Guide,” available at www.inetres.com/gp/military/cv/index.html.

Note: mpg = miles per gallon; n.a. = not applicable.

a. The liner protects vehicle occupants from hull fragments.

A2/A3/A4/A5

Date of Introduction 1962 (Original M109) 1992

Combat Weight (Tons) 28 32

Range (Miles) 217 186

Capacity (Gallons) 135 133

Efficiency (mpg) 1.6 1.4

155 155

Dimensions (Length x width x height, in feet) 30 x 10 x 11 32 x 10 x 11

Improvements Over Previous Model

Armor n.a. Supplemental armor

Other n.a. Antispall linera

Onboard ballistic computer

Improved suspension

Enhanced engine cooling

Driver's night-vision device

A6 (Paladin)

Model

Fuel

Size of Cannon (Millimeters)
APPENDIX

B

CBO’s Methods for Estimating Airlift Requirements

The Congressional Budget Office (CBO) relied primarily on planning factors developed by the Air Force to 

estimate the number of airlift sorties needed to deploy 

Army units overseas.1 Using the Air Force’s planned fleet 

of 180 C-17s as its basis, CBO estimated how long it 

would take the Air Force to deliver units’ equipment under two conditions—first, to areas where extensive airport facilities would support an unlimited number of 

daily sorties, and second, to regions of the world where 

airport facilities were more limited.

Unconstrained Airlift Operations

The delivery of cargo to a theater with extensive airport 

and aircraft-handling facilities would be limited only by 

the capacity of the transport fleet to deliver cargo. That 

is, if the receiving airport was big enough and had 

enough aircraft-servicing capability to handle hundreds 

of aircraft at one time, then the amount of cargo that 

could be delivered in one day would be determined by 

the number of sorties that an airlift fleet could generate. 

Under the assumptions of the Air Force’s planning factors, the number of sorties that a fleet can generate per 

day is equal to the number of aircraft in the fleet (#AC) 

times the number of hours each aircraft will fly, on average, per day (which is referred to as the utilization—

UTE—rate), divided by the time needed to fly to and 

from the destination (round-trip flying time, or RTFT; 

see Equation 1).2

Equation 1:

Number of sorties per day = (#AC) x (UTE rate)

RTFT

CBO estimates that the round-trip flying time for deploying units from Savannah, Georgia, to Djibouti in 

East Africa (the example destination used in the text of 

this report) is roughly 40 hours.3 For surge conditions—

those that might apply for the first 45 days of a military 

operation—the Air Force uses a C-17 UTE rate of 

14.5 hours per day; for sustained operations, it uses a 

daily planning value of 12.5 hours.4

 If Djibouti’s airfields 

were sufficiently large, the programmed C-17 fleet—

under the assumption of the Air Force’s planning values—could deliver 65 sorties per day to Djibouti in surge 

conditions or 56 sorties per day in a sustained-operations 

condition, CBO estimates.

Constrained Airlift Operations

In operations that deliver cargo to locations whose airfield facilities are limited, two factors determine the maximum number of daily airlift sorties: the maximum number of aircraft that can be serviced on the ground at one 

time (MOG) and the amount of time that an aircraft 

spends on the ground at the destination airport (GT). 

Based on the relationship used by the Air Force, the number of daily sorties that can be supported by an airfield 

with limited capacity is equal to the MOG times the 

number of hours per day that the airfield is in operation 

1. Department of the Air Force, Air Mobility Command, Air Mobility Planning Factors, Pamphlet 10-1403 (December 18, 2003). 

That material is also available at www.e-publishing.af.mil/

pubfiles/af/10/afpam10-1403/afpam10-1403.pdf.

2. Ibid., p. 4.

3. Although the direct distance is 6,700 nautical miles and the C-17 

has an average cruising speed of about 400 knots, such an aircraft 

cannot fly the entire distance nonstop when carrying a full payload. The time needed to make the full trip includes that of several 

legs—each of which is less than 4,500 nautical miles—between 

major Air Force facilities.

4. Department of the Air Force, Air Mobility Command, Air Mobility Planning Factors, Table 6.
72 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Table B-1.

CBO’s Estimates of Maximum Airfield 

Capacity

Source: Congressional Budget Office based on Department of 

the Air Force, Air Mobility Planning Factors, Pamphlet

10-1403 (December 18, 2003), Table 8.

Note: The numbers incorporate the Air Force’s planning factors: 

ground time equals 3.25 hours, and efficiency equals 85 percent.

c. Sixteen hours per day.

(OH) times the queuing efficiency at the airfield (Eff) divided by the average time spent on the ground (GT; see 

Equation 2).

Equation 2:

Number of sorties per day = (MOG) x (OH) x (Eff)

(GT)

For airlift operations into Djibouti, CBO made several 

assumptions that are consistent with the Air Force’s planning factors:5

B The airfield would operate (=OH) 24 hours a day during the first 45 days of an operation and only during 

daylight hours—assumed to be 16 hours per day—

after the first 45 days; 

B Queuing efficiency (Eff) would equal 85 percent; and

B Ground time (GT) would equal 3.25 hours for C-17 

deliveries.

CBO also assumed that the Djibouti airfield would have 

a MOG value of three, which would be fairly typical for a 

country with such a poorly developed infrastructure.6

Using those values, CBO estimated that the Air Force 

would be able to process 19 C-17 sorties per day through 

the Djibouti airport by operating 24 hours a day in surge 

conditions but in sustained operations would be able to 

handle only 13 sorties per day (see Table B-1).

Maximum Number of

Aircraft on Ground

1 64

2 13 8

3 19 13

4 25 17

 Number of C-17 Sorties

Operations Operationsa

24-Hour Daylight 

5. Ibid., Tables 5 and 8.

6. See the entry on Djibouti in the Central Intelligence Agency’s 

The World Factbook, available at www.cia.gov/cia/publications/

factbook/index.html; and Congressional Budget Office, Options 

for Restructuring the Army (May 2005), Appendix C.
APPENDIX

C

Definitions of Technology Readiness Levels and 

Assessments of Critical Technologies for the

Army’s Future Combat Systems Program

The National Aeronautics and Space Administration 

has developed a scheme of technology readiness levels 

(TRLs) that measures the progress of development in 

space programs. Using a scale of 1 to 9, the levels refer to 

technologies that range from those existing only on paper 

to those that have been demonstrated in operational tests 

in typical mission conditions (see Table C-1). The Department of Defense has adopted those measures to assess 

the technological readiness of defense programs, and the 

Army has used them to evaluate a number of technologies 

(ranging from 31 to 54, depending on when they were 

measured) that it considers critical to developing its Future Combat Systems (FCS). 

The Army has conducted several assessments of the readiness of the technologies that it considers critical to FCS 

development since the beginning of 2003 (see Table C-2 

on page 77 and Table C-3 on page 78). The first one, 

which identified 31 critical technologies, was conducted 

at about the time that the FCS program entered the system development and demonstration phase in the spring 

of 2003. Subsequent assessments were made in the fall of 

2004 by the FCS program manager’s office and by an independent team assembled by the Deputy Assistant Secretary of the Army for Research and Technology.1 By that 

time, the 31 critical technology areas had been expanded 

into 54 more specific critical technologies. In April 2005 

an assessment update was conducted by Deputy Assistant 

Secretary of the Army for Research and Technology.2

 Between the October 2004 and the April 2005 assessment 

updates, the number of critical technologies had been reduced to 49, the Army having concluded that five of the 

previously identified 54 critical technologies were no 

longer needed to develop the FCS components prior to 

initial fielding. 

1. Office of the Deputy Assistant Secretary of the Army for Research 

and Technology, Future Combat Systems (FCS) Increment 1 Technology Readiness Assessment (TRA) Update (October 2004).

2. Office of the Deputy Assistant Secretary of the Army for Research 

and Technology, Technology Readiness Assessment Update (April 

2005).
74 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Table C-1.

Definitions and Descriptions of Technology Readiness Levels

Continued

Technology Readiness Level Description Hardware and Software

Demonstration

Environment

1. Basic Principles Observed 

and Reported

At lowest level of technology 

readiness, scientific research 

begins to be translated into 

applied research and 

development

Examples might include paper 

studies of a technology’s 

basic properties

None (Paper studies and 

analysis)

None

2. Technology Concept or 

Application Formulated

Invention begins—once 

basic principles are 

observed, practical 

applications can be invented

The application is speculative, 

and there is no proof or 

detailed analysis to support 

the assumption

Examples are still limited to 

paper studies

None (Paper studies and 

analysis)

None

3. Analytical and Experimental 

Critical Function or 

Characteristic Proof of 

Concept

Active research and 

development is initiated, 

including analytical and 

laboratory studies to 

physically validate analytical 

predictions of separate 

elements of the technology

Examples include 

components that are not yet 

integrated or representative

Analytical studies and 

demonstration of nonscale 

individual components 

(Portions of subsystems)

Laboratory

4. Component or “Breadboard” 

Validation in a Laboratory 

Environment

Basic technological 

components are integrated to 

establish that the pieces will 

work together (relatively 

“low fidelity” compared with 

the eventual system)

Examples include integration 

of “ad hoc” hardware in a 

laboratory

Low-fidelity breadboard

Integration of nonscale 

components to show that 

pieces will work together

Pieces are not fully functional 

in form or fit but 

representative of technically 

feasible approach suitable 

for fielded systems

Laboratory
APPENDIX C DEFINITIONS OF TECHNOLOGY READINESS LEVELS AND ASSESSMENTS OF CRITICAL TECHNOLOGIES FOR THE FCS PROGRAM 75

Table C-1.

Continued

Continued

Technology Readiness Level Description Hardware and Software

Demonstration

Environment

5. Component or Breadboard 

Validation in a Relevant 

Environment

Fidelity of breadboard 

technology increases 

significantly

The basic technological 

components are integrated 

with reasonably realistic 

supporting elements so that 

the technology can be tested 

in a simulated environment

Examples include “highfidelity” laboratory 

integration of components

“High-fidelity” breadboard

The technology is functionally 

equivalent but not necessarily 

final in form or fit (size, 

weight, materials, and so 

forth)

Components should be 

approaching appropriate 

scale

The level may include 

integration of several 

components with reasonably 

realistic supporting elements 

or subsystems to demonstrate functionality

Laboratory for demonstrating 

functionality but not form and 

fit

May include demonstrating 

breadboard in surrogate 

vehicle

The technology is ready for 

detailed design studies

6. System/Subsystem Model or 

Prototype Demonstration in a 

Relevant Environment

A representative model or 

prototype system, which is 

well beyond the breadboard 

tested for TRL 5, is tested in a 

relevant environment 

representing a major step up 

in a technology’s 

demonstrated readiness

Examples include testing a 

prototype in a “high-fidelity” 

laboratory environment or 

simulated operational 

environment

The prototype should be very 

close to final in form, fit, and 

function and should probably 

integrate many new 

components and realistic 

supporting elements or 

subsystems if needed to 

demonstrate full functionality 

of the elements or subsystem

“High-fidelity” laboratory 

demonstration or limited/

restricted flight or road 

demonstration in a relevant 

environment

Integration of the technology 

is well defined

7. System Prototype 

Demonstration in an 

Operational Environment

The prototype is near or at 

the level of the planned 

operational system

This level represents a major 

step up from TRL 6, requiring 

the demonstration of an 

actual system prototype in an 

operational environment, 

such as in an aircraft or 

vehicle or in space

Examples include testing the 

prototype in a test-bed 

vehicle

The prototype should be 

integrated with other key 

supporting elements or 

subsystems to demonstrate 

the full functionality of the 

element or subsystem

Demonstration in a 

representative operational 

environment, such as a testbed or demonstrator vehicle

Technology is well 

substantiated with test data
76 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Table C-1.

Continued

Source: Government Accountability Office, Defense Acquisitions: Improved Business Case Is Needed for Future Combat System’s Successful 

Outcome, GAO-06-367 (March 2006), p. 49.

Technology Readiness Level Description Hardware and Software

Demonstration

Environment

8. Actual System Completed and 

“Flight or Field Qualified” 

Through Test and 

Demonstration

The technology has been 

proven to work in its final 

form and under expected 

conditions

In almost all cases, this TRL 

represents the end of true 

system development

Examples include 

developmental test and 

evaluation of the system in its 

intended weapon structure to 

determine if it meets design 

specifications

Field-qualified hardware Developmental test and 

evaluation in the actual 

system application

9. Actual System “Flight or Field 

Proven” Through Successful 

Mission Operations

The technology is applied in 

its final form and under 

mission conditions, such as 

those encountered in 

operational test and 

evaluation

In almost all cases, this is the 

end of the last “bug fixing” 

aspects of true system 

development

Examples include operating 

the system under mission 

conditions

Actual system in final form Operational test and 

evaluation in mission 

conditions
APPENDIX C DEFINITIONS OF TECHNOLOGY READINESS LEVELS AND ASSESSMENTS OF CRITICAL TECHNOLOGIES FOR THE FCS PROGRAM 77

Table C-2.

Technology Readiness Levels of Critical Technologies for the FCS Program in

May 2003

Source: Congressional Budget Office based on data from the Department of the Army.

Notes: FCS = Future Combat Systems; UAV = unmanned aerial vehicle; NLOS-LS = non-line-of-sight launch system; UGV = unmanned 

ground vehicle; MGV = manned ground vehicle. 

a. Assessment by the Deputy Assistant Secretary of the Army for Research and Technology.

b. No longer required for initial fielding of FCS components.

Technology

Readiness Level in Component for Which

May 2003a Technology Is Needed

Software Programmable Radio 6 Network

Interface and Information Exchange 4.5 Network

Security Systems and Algorithms 5.5 Network

Mobile Ad Hoc Networking Protocols 6 Network

Quality of Service Algorithms 5 Network

Unmanned Systems Relay 6 UAVs

Wideband Waveforms 5 Network

Advanced Man-Machine Interfaces 6 Network

Multispectral Sensors and Seekers 5.5 Network

Decision Aids and Intelligent Agents 6 Network

Combat Identification 5.5 Network

Rapid Battlespace Deconfliction 6 Network

Sensor/Data Fusion and Data Compression Algorithms 4.5 Network

Dynamic Sensor-Shooter Pairing Algorithms and Fire Control 5 Network

Line-of-Sight/Beyond-Line-of-Sight/Non-Line-of-Sight (Terminal guidance) 5 MGVs, NLOS-LS

Aided and Automatic Target Recognition 5.5 UGVs, Network, NLOS-LS

Recoil Management and Lightweight Components 4 MGVs

Distributive Collaboration of Manned/Unmanned Platforms 5 UGVs

Rapid Battle Damage Assessment 4 No longer requiredb

High-Power Density/Fuel-Efficient Propulsion 5 MGVs

Embedded Predictive Logistics Sensors and Algorithms 5.5 MGVs, UGVs, UAVs

Water Generation and Purification 5.5 No longer requiredb

Computer-Generated Forces 6 Network, MGVs

Tactical Engagement Simulation 5 Network, MGVs

Active Protection System 5 MGVs

Signature Management 5 MGVs

Lightweight Hull and Vehicle Armor 5.5 UGVs, MGVs

Health Monitoring and Casualty Care Interventions 8 Network, MGVs

Power Distribution and Control 5 UGVs, MGVs

Advanced Countermine Technology 4.5 Network, MGVs, UGVs

High-Density Packaged Power 5.5 UGVs, MGVs
78 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

Table C-3.

Status of Critical Technologies for the FCS Program As Assessed After May 2003

Continued

DAS Program DAS Program Component

(R&T) Manager (R&T) Manager for Which

Program April May Program April May Technology

Manager IRT 2005 2006 Manager IRT 2005 2006 Is Needed

Software Programmable Radio

JTRS Cluster 1 5 5 5 6 2006 2006 2007 2006 Network

JTRS Cluster 5 5 5 5 6 2006 2006 2007 2006 Network

WIN-T 5 5 5 6 2006 2006 2007 2006 Network

Interface and Information Exchange

Army, joint, multinational interface 4 4 4 6 2006 2007+ 2008 2006 Network

WIN-T strategic communication 4 4 4 6 2006 2007+ 2008 2006 Network

Security Systems and Algorithms

Cross-domain guarding solution 3 3 4 6 2006 2007+ 2008 2006 Network

Intrusion detection—Internet protocol 5 5 4 4 2006 2007+ 2008 2008 Network

Intrusion detection—network waveform 3 3 4 4 2006 2007+ 2007 2007 Network

Mobile Ad Hoc Networking Protocols 5 5 5 5 2006 2007+ 2007 2007 Network

Quality of Service Algorithms 5 5 5 5 2006 2007+ 2007 2008 Network

Unmanned Systems Relay 5 5 5 n.r. 2006 2006 2006 n.r. UAVs

Wideband Waveforms

JTRS 5 5 5 6 2006 2007+ 2007 2006 Network

Soldier radio waveform 4 4 4 6 2006 2007+ 2007 2006 Network

Advanced Man-Machine Interfaces 6 5 6 6 2006 2006 2005 2005 Network

Multispectral Sensors and Seekers 6 6 6 6 2006 2006 2005 2005 Network

Decision Aids and Intelligent Agents 6 6 6 6 2006 2006 2005 2005 Network

Combat Identification

Air (rotary wing/UAV)-to-ground 6 6 6 6 2006 2006 2005 2005 Network

Air (fixed wing)-to-ground 4 4 NLR NLR 2007+ 2006 NLR NLR n.a.

Ground-to-air 3 3 NLR NLR 2007+ 2006 NLR NLR n.a.

Ground-to-ground (Mounted) 6 6 6 6 2006 2006 2005 2005 Network

Ground-to-soldier 4 4 NLR NLR 2007+ 2006 NLR NLR n.a.

Rapid Battlespace Deconfliction 5 5 5 5 2006 2007+ 2008 2009 Network

Sensor/Data Fusion and Data Compression Algorithms

Distributed fusion management 4 4 4 4 2006 2007+ 2007 2007 Network

Level 1 fusion engine 6 6 6 6 2006 2007+ 2005 2005 Network

Data-compression algorithms 6 6 6 6 2006 2007+ 2005 2005 Network

Dynamic Sensor-Shooter Pairing Algorithms and Fire

Control 6 5.5 5 6 2006 2006 2006 2006 Network

Line-of-Sight/Beyond-Line-of-Sight/Non-Line-of-Sight

(Terminal guidance)

Precision-guided mortar munitions 5 5 5 6 2006 n.r. 2007 2006 MGVs

Multirole precision munitions 6 4.5 5 6 2006 n.r. 2007 2006 MGVs

Excalibur precision munitions 5 5.5 6 6 2006 n.r. 2005 2005 MGVs

Non-line-of-sight launch system 6 5 6 6 2006 n.r. 2005 2005 NLOS-LS

Aided and Automatic Target Recognition

Aided target recognition for reconnaissance,

surveillance, and target acquisition 5 5 5 5 2006 2006 2007 2008 UGVs

Non-line-of-sight launch system aided target

recognition for seekers 6 5 6 6 2006 2006 2005 2005 Network, NLOS-LS

Assessments (TRL) Projected Attainment of TRL 6

Oct. 2004 Oct. 2004

Technology Readiness 
APPENDIX C DEFINITIONS OF TECHNOLOGY READINESS LEVELS AND ASSESSMENTS OF CRITICAL TECHNOLOGIES FOR THE FCS PROGRAM 79

Table C-3.

Continued

Source: Congressional Budget Office based on data from the Department of the Army; Deputy Assistant Secretary of the Army for Research 

and Technology, Future Combat Systems (FCS) Increment 1 Technology Readiness Assessment (TRA) Update (October 2004); and 

Deputy Assistant Secretary of the Army for Research and Technology, Technology Readiness Update Assessment (April 2005).

Notes: FCS = Future Combat Systems; DAS (R&T) = Deputy Assistant Secretary of the Army for Research and Technology; IRT = Independent Review Team; JTRS = Joint Tactical Radio System; WIN-T = Warfighting Information Network-Tactical; n.r. = not reported; n.a. 

= not applicable; UAV = unmanned aerial vehicle; NLR = no longer required for initial fielding of FCS components; MGV = manned 

ground vehicle; NLOS-LS = non-line-of-sight launch system; UGV = unmanned ground vehicle.

a. Upgraded to TRL 5 by the Army in January 2006 on the basis of tests conducted in the fall of 2005.

b. Upgraded to TRL 6 by the Army in January 2006 on the basis of tests conducted in August 2005.

DAS Program DAS Program Component

(R&T) Manager (R&T) Manager for Which

Program April May Program April May Technology

Manager IRT 2005 2006 Manager IRT 2005 2006 Is Needed

Recoil Management and Lightweight Components 5 5 6 6 2006 2007+ 2005 2005 MGVs

Distributive Collaboration of Manned/Unmanned 

Platforms 5 5 5 5 2006 2006 2006 2006 UGVs

Rapid Battle Damage Assessment 3 4 NLR NLR 2007+ 2007+ NLR NLR n.a.

High-Power Density/Fuel-Efficient Propulsion

High-power density engine 5 5 5 6 2006 2006 2007 2006 MGVs

Fuel-efficient hybrid-electric engine 6 6 6 6 2006 2006 2005 2005 MGVS

Embedded Predictive Logistics Sensors and Algorithms 2 4.5 5 n.r. 2007+ 2007+ 2008 n.r. MGVs, UGVs, 

UAVs

Water Generation and Purification 5 5 NLR NLR 2007+ 2007+ NLR NLR n.a.

Computer Generated Forces 6 6 6 6 2006 2006 2005 2005 Network, MGVs

Tactical Engagement Simulation 4 4 4a 5 2006 2007+ 2008 2008 Network, MGVs

Active Protection System

Active protection system 6 6 5 6 2006 2006 2008 2006 MGVs

Threat warning system 4 4.5 4 4.5 2007+ 2007+ 2009 2009 MGVs

Signature Management 5 5.5 5 6 2006 2006 2006 2006 MGVs

Lightweight Hull and Vehicle Armor 5 5 5 5 2006 2007+ 2008 2008 UGVs, MGVs

Health Monitoring and Casualty Care Interventions 8 6 6 6 2005 2006 2005 2005 Network, MGVs

Power Distribution and Control 5 5 5 6 2006 2006 2006 2006 UGVs, MGVs

Advanced Countermine Technology

Mine detection 6 6 6 6 2006 n.r. 2005 2005 Network, UGVs

Mine neutralization 6 6 6 6 2006 n.r. 2005 2005 UGVs

Efficient resource allocation 6 6 6 n.r. 2006 n.r. 2005 n.a. Network, UGVs

Protection 4 4 4 4 2007+ n.r. 2008 2008 MGVs

High-Density Packaged Power 5 5 5 6 2006 2006 2008 2006 UGVs, MGVs

Class 1 UAV Propulsion Technology

Ducted fan 4 4 4b 6 2006 2006 2005 2005 UAVs

Lightweight heavy-fuel engine 3 3 4 5 2006 2006 2007 2006 UAVs

Oct. 2004 Oct. 2004

Technology Readiness 

Assessments (TRL) Projected Attainment of TRL 6

APPENDIX

D

Methods Used to Estimate Costs

To estimate the costs of the alternatives considered in 

this analysis, the Congressional Budget Office (CBO) 

had to establish the costs of individual components of the 

Future Combat Systems (FCS) program and the associated network as well as the costs of upgrades to existing 

weapon systems. This appendix describes the methods 

that CBO used to assess the research and development 

(R&D) and procurement costs of the FCS components 

and network and the costs of upgrades. It also briefly discusses the risk that costs may grow beyond their original 

estimates over the life of the program.

Estimating Costs of FCS Components

The Department of Defense (DoD) submits annual Selected Acquisition Reports (SARs) to the Congress that 

provide estimates of costs for major weapons programs. 

The SARs for the FCS program provide separate estimates of the total R&D and total procurement costs for 

the program’s first increment (that is, the first 15 brigades’ worth of equipment). On the basis of those reports, CBO developed independent estimates of the costs 

of individual FCS components, separating those expenditures into R&D and procurement costs.

Research and Development Costs

Total R&D costs for the FCS program, according to the 

Army’s latest estimates, are projected to be $29 billion (in 

2006 dollars).1 CBO apportioned those costs to the various types of systems—such as manned ground vehicles or 

unmanned aerial vehicles (UAVs)—on the basis of spending planned by the Army for 2005 through 2011. Under 

those plans, manned vehicles would account for about 

20 percent of total R&D costs; UAVs would account for 

2 percent; unmanned ground vehicles, for 3 percent; the 

non-line-of-sight launch system (NLOS-LS), for 5 percent; and unmanned ground sensors and the intelligent 

munitions system together, for 1 percent. CBO assumed 

that 20 percent of R&D costs would be spent on program management and that the remainder, about 50 percent, would go toward software and network development and systems integration. In developing the costs of 

the various alternatives it considered, CBO attributed 

portions of those management, development, and integration costs to individual systems on the basis of a system’s share of total R&D costs.

Procurement Costs

CBO estimated the portion of the procurement costs for 

each brigade’s worth of FCS equipment that could be assigned to individual systems or groups of systems. According to recent FCS SARs, the total cost of procuring 

15 brigades’ worth of FCS components would be about 

$100 billion, or an average unit cost of $6.7 billion. The 

average unit cost covers more than 800 individual systems—including manned vehicles, UAVs, and unmanned ground vehicles—and the network. CBO used 

several different methods to estimate the costs for 

procuring the various components of the FCS-equipped 

brigades.

Manned Vehicles. The costs of manned vehicles make up 

the bulk of the costs associated with an FCS-equipped 

brigade. All told, 322 manned vehicles would be needed 

to equip an FCS brigade; an additional 11 vehicles would 

be required as spares (known as “operational float”).2

 In 

assessing the costs of the eight different manned FCS vehicles, CBO combined a cost-estimating relationship 

(CER) developed by Technomics and the Army’s Cost 

and Economic Analysis Center with the previously esti1. These costs include the total estimated R&D costs for the FCS 

program for the years from 2003 through 2016.

2. Quantities are based on those in Logistics Requirements and 

Readiness IPT, Materiel Fielding Sub-IPT, of the Boeing/SAIC 

Lead Systems Integrator, Future Combat Systems (FCS): Equipped 

Unit of Action (UA) Materiel Fielding Plan (MFP) to the UA Supportability Strategy (April 2005), pp. 27 and 57.
82 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

mated costs of the Crusader artillery system.3 (The CER 

relates the cost of manned armored vehicles to their characteristics—such as speed, armament, and passenger capacity—as well as to the year in which the vehicle is first 

produced.)4

 CBO also used the estimated costs of the 

Crusader to determine a unit cost for the proposed nonline-of-sight cannon and to calibrate the estimates derived from the CER.5 Using those methods, CBO estimated that the manned vehicles would account for 

$4.2 billion (63 percent) of the total cost of a brigade’s 

worth of FCS equipment.

Unmanned Ground and Aerial Vehicles. CBO relied primarily on the Army’s estimates of the unit costs of unmanned ground vehicles, which ranged from $1 million 

to $5 million.6

 On the basis of those costs, CBO estimated that the total cost of unmanned FCS ground vehicles for a brigade would account for roughly $700 million 

(10 percent) of the total cost of a brigade’s worth of 

equipment.

For the most part, CBO estimated the costs of UAVs by 

using CERs developed by Technomics for the Deputy Assistant Secretary of the Army for Cost and Economics.7

Separate CERs were used to determine the cost of the 

aerial vehicle and the ground station associated with each 

class of UAVs. Again, estimates obtained using the CERs 

were compared with estimates of existing systems and adjusted as necessary. The resultant total cost of the UAVs 

(which would number more than 200 in each brigade under the Administration’s plan) and accompanying launch 

units, according to CBO’s estimates, would account for 

$350 million (5 percent) of the total costs of FCS equipment for one brigade.

Remaining Unattended Systems. Cost estimates that 

CBO developed for the three remaining weapon systems—unattended ground sensors, the NLOS-LS, and 

the improved munitions system—were all based on the 

costs of existing systems or systems in development:

B Unit costs for the ground sensors were based loosely 

on those for REMBASS II—the Army’s remotely 

monitored battlefield sensor system;

B Costs for the NLOS-LS were based on those for the 

high-mobility advanced rocket system (HIMARS) 

launcher; costs for the NLOS-LS munitions, on those 

for the guided rockets for the multiple launch rocket 

system (GMLRS); and

B Costs for the improved munitions system were based 

on those of the Spider smart-mine system.

Total costs for equipping a brigade with those systems 

would be roughly $300 million, or 5 percent of the costs 

for equipping it with all FCS components.

The Network. The remainder of the costs to procure a brigade’s worth of FCS components would be approximately $1.1 billion, in CBO’s estimation, or 17 percent 

of the total. CBO assumed that those costs could be attributed to the network.

Basis for Estimates of Cost Growth

CBO based its estimates of the potential for growth in 

the costs of FCS components largely on research conducted by the RAND Corporation. RAND has compiled 

a database covering cost growth from 1969 to 1999 for all 

major programs for which DoD submitted annual SARs 

to the Congress during that period.8 (The database includes 3,047 SARs for 274 programs.) Analysts compared 

3. The Crusader program was canceled in 2002.

4. Steve Pawlow, Army Cost and Economic Analysis Center, and Jeff 

Cherwonik and Paul Hardin, Technomics, “Ground Vehicle Procurement Cost Estimating Methodology,” presented at the 35th 

DoD Cost Analysis Symposium, Williamsburg, Va., January 

2002.

5. Estimates of costs for the Crusader system were based on Government Accountability Office, Army Armored Systems: Meeting Crusader Requirements Will Be a Technical Challenge, GAO/NSIAD97-121 (June 1997); and Office of the Undersecretary of Defense 

for Acquisition and Technology, Selected Acquisition Report 

Summary Tables, December 31, 1997.

6. Private correspondence provided by the Army to the Congressional Budget Office.

7. Technomics and the Office of the Deputy Assistant Secretary of 

the Army for Cost and Economics, “Unmanned Aerial Vehicle 

System Acquisition Cost Estimating Methodology,” presented at 

the 37th DoD Cost Analysis Symposium, Williamsburg, Va., February 2004.

8. At the time this analysis was prepared, the most recent RAND 

publication based on its SAR database was Jeanne M. Jarvaise, 

Jeffrey A. Drezner, and D. Norton, The Defense System Cost Performance Database: Cost Growth Analysis Using Selected Acquisition 

Reports, MR-625-OSD (Santa Monica, Calif.: RAND, 1996). 

The estimates of cost growth that CBO used for its analysis are 

based on unpublished updates of that report prepared in 1999 

through 2002 by Robert S. Leonard, Fred Timson, and John C. 

Graser.
APPENDIX D METHODS USED TO ESTIMATE COSTS 83

Table D-1.

Rates of Historical Cost Growth for Military Systems

(Percent)

Source: Congressional Budget Office based on analysis by RAND.

Note: The growth of total development or procurement costs is measured from the estimates made of such costs when the system enters 

the system development and demonstration phase.

DoD’s estimates of costs for those programs at Milestone 

B (entry into the system development and demonstration 

phase)—when extensive development activity begins—

with DoD’s estimates for the systems’ costs once they had 

gone into production and become operational.9

 RAND 

developed estimates of increases or decreases in development and procurement costs for eight categories of systems, including ships, ground combat vehicles, and aircraft, breaking down the data by service and type of 

weapon.10

RAND’s analysis suggests that most DoD weapons programs increase in cost.11 However, R&D and procurement costs for Army ground combat vehicles have experienced some of the highest growth rates—both types of 

costs have risen by more than 70 percent relative to early 

estimates. Other systems being developed in the FCS 

program have experienced cost growth at lower rates,

according to RAND (see Table D-1).

To determine an overall potential for cost growth for the 

Administration’s FCS program and for the alternatives 

presented in this study, CBO applied the rate relevant for 

each kind of system to the R&D and procurement costs 

allotted to the various portions of the FCS program. 

CBO estimates the potential for cost growth in the 

planned FCS program to be 67 percent for the R&D 

portion and roughly 60 percent for the cost to procure 

15 brigades’ worth of FCS components.

Estimates of Costs to Upgrade

Current Systems

The modernization of current systems that CBO considered in its analysis was basically of two types: upgrades of 

systems to a more recent model or the incorporation of 

FCS technology into an existing system. In general, CBO 

relied on the Army’s estimates of the costs for such modernization. Some of the Army’s estimates are based on upgrades that have been made to existing systems for several 

years. (For example, the Army has been upgrading older 

models of its M1 Abrams tanks to the M1A2 model for 

more than 10 years.) The Army has also assessed the costs 

for upgrading current systems with FCS technologies; 

Type of System

Command, Control, Communications, and Intelligence 69 19

Ground Combat Vehicles 71 74

Missiles and Munitions 45 35

Unmanned Aerial Vehicles 42 23

Research, Development,

 Testing, and Evaluation Procurement

9. Major DoD programs go through a series of stages that are outlined in DoD’s acquisition regulations. Milestone B (formerly 

Milestone II) represents a program’s entrance into the system 

development and demonstration stage. A discussion of those milestones and stages is included in DoD Instruction 5000.2, dated 

May 12, 2003, available at www.dtic.mil/whs/directives/corres/

pdf2/i50002p.pdf.

10. The Institute for Defense Analyses (IDA) has also analyzed trends 

in weapons costs using a database constructed from DoD’s 

Selected Acquisition Reports. Like RAND, IDA produced separate estimates for the different military services and for various 

types of systems, but it used slightly different methods in estimating cost growth—adjusting for model changes as well as for 

changes in total quantity—and its estimates covered a somewhat 

different group of systems. Nonetheless, its estimates of past cost 

growth mostly equal or exceed those reported by RAND. See 

Karen W. Tyson and others, The Effects of Management Initiatives 

on the Costs and Schedules of Defense Acquisition Programs (Alexandria, Va.: Institute for Defense Analyses, 1992); and Karen W. 

Tyson, Bruce R. Harmon, and Daniel M. Utech, Understanding 

Cost and Schedule Growth in Acquisition Programs (Alexandria, Va.: 

Institute for Defense Analyses, 1994).

11. For additional discussion of cost growth in DoD programs, see 

Congressional Budget Office, The Long-Term Implications of Current Defense Plans (January 2003), pp. 44-46.
84 THE ARMY’S FUTURE COMBAT SYSTEMS PROGRAM AND ALTERNATIVES

such costs ranged from $700,000 per upgraded M113 to 

$8 million per upgraded Abrams tank.

Like the costs for other aspects of the FCS program, those 

for inserting FCS technology into existing systems could 

experience growth by the time the upgrades are actually 

carried out. Therefore, CBO applied likely rates of 

growth to those portions of the upgrade costs that would 

apply to FCS components. The rates were based on those 

experienced in programs to upgrade the Abrams tank and 

Bradley fighting vehicle from 1994 to 2003 and averaged 

50 percent.12

12. See Office of the Principal Deputy Undersecretary of Defense for 

Acquisition Technology and Logistics, “Remanufacture of 

Defense Systems: Case Studies of Cost Experiences and Lessons 

for Future Programs” (November 2001), presented at the 35th 

DoD Cost Analysis Symposium, Williamsburg, Va., January 

2002.