a

GAO

United States Government Accountability Office

Report to Congressional Committees

July 2004 DEFENSE 

ACQUISITIONS

Space-Based Radar 

Effort Needs 

Additional Knowledge 

before Starting 

Development

GAO-04-759

The Web version of this report was reposted on 

July 26, 2004, to reflect congressional developments 

since the original version was posted July 23, 2004. The 

following items were revised to 1) add new addressees 

to the report on (page 1), which shifted text throughout; 

2) add a sentence to reflect the appropriations 

committee’s action on the SBR program on July 21, 2004 

(page 7); and 3) add a sentence to the introduction 

explaining that this work was done under the Comptroller 

General’s authority and clarifying why we were addressing 

the report to the committees (page 2).

The printed version reflects these changes.
www.gao.gov/cgi-bin/getrpt?GAO-04-759.

To view the full product, including the scope 

and methodology, click on the link above. 

For more information, contact Katherine V. 

Schinasi at (202) 512-4841 or 

schinasik@gao.gov. 

Highlights of GAO-04-759, a report to 

congressional committees 

July 2004

DEFENSE ACQUISITIONS 

Space-Based Radar Effort Needs 

Additional Knowledge before Starting 

Development 

Although SBR is 2 years away from product development, the program 

already faces major challenges. DOD officials say SBR will likely be the most 

expensive and technically challenging space system ever built by DOD. The 

acquisition time frame is much shorter than what has been achieved in the 

past for other complex satellite systems. Finally, DOD is setting precedence 

by taking the lead on developing SBR with the intelligence community as a 

partner. Most DOD space programs that GAO has reviewed in the past 

several decades were hampered by schedule and cost growth and 

performance shortfalls. Problems were largely rooted in a failure to match 

requirements with resources when starting product development. 

Commitments were made without knowing whether technologies being 

pursued would work as intended. To avoid these problems, leading 

commercial firms have adopted a knowledge-based model that enables 

decision makers to be reasonably certain about their products at critical 

junctures and helps them make informed investment decisions. 

Although DOD has taken positive steps to strengthen the involvement of 

senior leaders within DOD and the intelligence community in setting 

requirements, SBR’s concept of operations has not been approved and 

signed by requirements boards for either of the two partners. Without 

documentation and formal approval, it is unclear who will be held 

accountable for setting requirements or how disagreements among SBR’s 

partners will be resolved when DOD moves SBR into ensuing phases of 

acquisition. 

DOD has adopted noteworthy practices to gain knowledge about SBR’s 

resources. These include maximizing the use of systems engineering to close 

gaps between requirements and resources; estimating all of SBR’s costs; 

exploring alternatives for SBR if the Transformational Communications 

Architecture (TCA)—the communications infrastructure that is expected to 

relay SBR data across a network of users—incurs schedule and performance 

shortfalls; and asking contractors to propose multiple operations concepts 

for SBR with or without TCA. Despite these accomplishments, DOD is at risk 

of knowledge gaps. SBR’s critical technologies will not be mature when 

product development starts, as called for by best practices. One of TCA’s 

primary components may not be ready in time to support SBR data. These 

knowledge gaps make it harder for DOD to reliably estimate how much time 

and money are needed to complete SBR’s development. If TCA is delayed, 

DOD’s alternatives may involve reducing SBR’s capabilities or significantly 

increasing program cost. Without sufficient knowledge, DOD may not be 

able to determine by the time SBR’s product development starts in 2006 

whether space-based radar is best suited to tracking moving targets on land 

or at sea or whether air-based radar would provide enough capabilities at far 

less cost. More specific analyses would help DOD weigh the merits of 

various alternatives and assess how much to invest in the SBR acquisition 

program versus air platforms with similar capabilities. 

Missing among the Department of 

Defense’s (DOD) portfolio of 

systems is a capability to track 

stationary and moving enemy 

vehicles on land or at sea in any 

type of weather, day or night, from 

space. To meet this need, DOD and 

the intelligence community are 

collaborating on the ambitious 

Space-Based Radar (SBR) program. 

By leveraging the newest 

generation of radar technologies, 

the SBR concept promises to 

deliver high-quality data to a wide 

array of users. DOD intends to start 

product development in 2006 and 

to field SBR satellites as quickly as 

possible so that warfighters, the 

intelligence community, and 

national decision makers can gain a 

better understanding of what 

adversaries are doing in specific 

locations around the world. GAO 

reviewed the SBR program to 

assess DOD’s progress in attaining 

the knowledge it needs by 2006 in 

terms of customer needs (or 

requirements) and resources. 

Before committing to SBR’s 

acquisition program in 2006, GAO 

recommends that DOD and 

intelligence partners close gaps in 

the requirements approval process 

in terms of documenting decisions 

and be prepared to add time and 

money or make trade-offs with 

other DOD space programs to 

address SBR’s requirements and 

resources. DOD generally agreed 

with our findings and partially 

agreed with our recommendations. 
Page i GAO-04-759 Space-Based Radar 

Letter 1

Scope and Methodology 3

Results in Brief 4

Background 6

Gaining Knowledge about Requirements and Resources before 

Product Development Is Important for Space Acquisition 

Success 7

DOD Moving Forward on Acquiring Critical Knowledge but Gaps 

Remain in Approval for SBR Requirements 9

DOD Taking Proactive Steps to Gain Knowledge about Resources, 

but Critical Gaps May Remain at Product Development 15

Conclusions 22

Recommendations for Executive Action 23

Agency Comments and Our Evaluation 24

Appendix I TRL Scale for Assessing Critical Technologies 27 

Appendix II Comments from the Department of Defense 28 

Tables 

Table 1: Knowledge Provided by SBR’s Initial Capabilities 

Document and Concept of Operations 14

Table 2: Technology Readiness Levels of SBR Critical Technologies 18

Figures 

Figure 1: SBR’s Acquisition Schedule (in fiscal years) 7

Figure 2: SBR’s Oversight Structure 11

Figure 3: Requirements-Setting Can Impact Acquisition Process 12

Contents 
Page ii GAO-04-759 Space-Based Radar 

Abbreviations 

AOA analysis of alternatives 

DOD Department of Defense 

R&D research and development 

SBR Space-Based Radar 

TCA Transformational Communications Architecture 

TRL Technology Readiness Level 

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Page 1 GAO-04-759 Space-Based Radar 

July 23, 2004 

The Honorable John Warner 

Chairman 

The Honorable Carl Levin 

Ranking Minority Member 

Committee on Armed Services 

United States Senate 

The Honorable Ted Stevens 

Chairman 

The Honorable Daniel Inouye 

Ranking Minority Member 

Subcommittee on Defense 

Committee on Appropriations 

United States Senate 

The Honorable Duncan Hunter 

Chairman 

The Honorable Ike Skelton 

Ranking Minority Member 

Committee on Armed Services 

House of Representatives 

The Honorable Jerry Lewis 

Chairman 

The Honorable John P. Murtha 

Ranking Minority Member 

Subcommittee on Defense 

Committee on Appropriations 

House of Representatives 

The Department of Defense (DOD) currently has ground-based and 

air-based radars but no capability to track moving targets from space. 

To meet a need for persistent global observation, DOD and the intelligence 

community are working together to develop the Space-Based Radar (SBR) 

system to find, identify, track, and monitor ground and sea targets—

mobile or immobile—under all-weather conditions and on a near-continual 

basis across large swaths of the earth’s surface. SBR is to enhance 

information gathering by providing intelligence, surveillance, and 

reconnaissance data in a meaningful and timely manner. 

United States Government Accountability Office

Washington, DC 20548 
Page 2 GAO-04-759 Space-Based Radar 

This is an ambitious program for DOD. DOD’s initial total cost estimate for 

SBR is about $28.6 billion from fiscal year 2003 to 2024. And although the 

technologies for tracking moving targets from space are still in 

development, DOD is scheduling almost 7 years between the start of 

product development and launch of the first SBR satellite—a time frame 

that is considerably shorter than what has been achieved in the past for 

other complex satellite systems. DOD would like to field SBR satellites as 

quickly as possible because it believes that SBR represents a major leap 

forward in providing the warfighters, intelligence community, and national 

decision makers with significant tactical, operational, and strategic 

advantages over potential adversaries. For example, DOD envisions that 

SBR will be able to see deep inside enemy territory without risk to 

personnel or resources and that it will operate over areas where 

conventional airborne surveillance systems are at risk from the enemy’s 

surface-to-air missiles, which can travel increasingly longer ranges. DOD 

also envisions that SBR will generate high-quality radar imagery of targets 

and terrain and interface with ground, air, and other space systems so that 

users can gain a better understanding of what is occurring in specific 

locations. 

DOD is in the early exploratory phase of the SBR program—a period when 

it gathers knowledge about its needs, or requirements, and explores the 

feasibility of meeting those requirements. DOD expects to begin product 

development in fiscal year 2006; at which point it will make a commitment 

to invest in a formal acquisition program for SBR. Our past work has 

shown that successful weapon system programs are able to match their 

needs to their resources—that is, money, technology, and time—before 

product development. With achievable requirements and commitment of 

sufficient investment to complete development, programs are better able 

to deliver products at cost and on schedule. Most space programs over the 

past several decades have not been able to achieve a match between needs 

and resources before product development and have incurred significant 

cost and schedule increases due in part to the need to rework technologies 

in the later stages of their acquisition. 

We conducted our review of the SBR program on the initiative of the 

Comptroller General. Given SBR’s overall importance to DOD and the 

intelligence community, we reviewed the SBR program to assess DOD’s 

progress in attaining the knowledge it needs by 2006 in terms of 

(1) requirements and (2) resources—technology, communications 

infrastructure, and funding. 
Page 3 GAO-04-759 Space-Based Radar 

We are addressing this report to you because of your jurisdiction over 

weapon systems acquisition. 

To assess DOD’s progress in attaining the knowledge it needs before the 

start of product development, we examined the resources (technology, 

communications infrastructure, and funding) committed and planned for 

the program as well as the users’ needs for an SBR system. We considered 

DOD’s plans for maturing the critical technologies when we obtained 

technology-readiness information for each critical technology (as well as 

its mature backup technology) against best practice standards to 

determine if they will be sufficiently mature when DOD plans to start 

product development. We also reviewed the SBR risk management plans 

and concept development contract information. We discussed these 

documents and issues with representatives from Air Force Space 

Command, Peterson Air Force Base, Colorado; and the SBR Joint Program 

Office, Space and Missile Systems Center, Los Angeles Air Force Base, 

California. 

To determine SBR’s role in a larger DOD architecture, we met with 

officials from the Joint Chiefs of Staff, Washington, D.C.; and the Air Force 

Directorate of Space Acquisitions, Arlington, Virginia. We also consulted 

past GAO reports to determine the relationship between SBR and the 

Transformational Communications Architecture. 

To determine the scope and completeness of the analysis of alternatives 

and its follow-on study to identify the optimal ways to gather information 

on ground moving targets from radars based in space versus air, we met 

with officials from Air Force Space Command; DOD Office of the Director, 

Program Analysis and Evaluation, Washington, D.C.; Air Force Directorate 

of Requirements for Space, Crystal City, Virginia; and the Air Force 

Studies and Analyses Agency, Arlington, Virginia. We also talked with an 

official from the Air Force Office of Aerospace Studies, Kirtland Air Force 

Base, New Mexico. 

We discussed overarching programmatic issues—including the level of 

coordination between DOD and the intelligence community—with 

representatives from the Air Force Directorate of Space Acquisitions. 

We were not able to obtain meetings with members of the Mission 

Requirements Board (a board within the intelligence community 

responsible for approving program requirements) or the intelligence 

agencies to discuss their stake in the SBR program. 

Scope and 

Methodology 
Page 4 GAO-04-759 Space-Based Radar 

We performed our work from November 2003 through June 2004 in 

accordance with generally accepted government auditing standards. 

DOD has inserted a great deal of management and stakeholder 

involvement into developing SBR so that it can gain greater knowledge 

about requirements before product development than it has in past 

programs. Senior-level officials from DOD, the military services, and the 

intelligence community are heading up three new SBR oversight groups to 

discuss what can and cannot be accomplished in terms of the desired time 

frame, available funding, and achievable technologies. The groups have so 

far attained informal agreement on requirements. However, this 

commitment has not been formalized, and it is unclear as to whether or 

how it will be formalized. Moreover, it is also unclear how disagreements 

that may occur later on among SBR’s partners will be resolved. Given the 

varied interests of SBR’s partners and past problems with securing 

agreement on requirements for space programs,1

 it is important that DOD 

build on the positive steps it has already taken and find ways to formalize 

commitment to requirements as well as SBR’s concept of operations. 

DOD is also taking positive steps in its effort to gain knowledge about 

SBR’s resources. These steps include strengthening systems engineering 

applications; estimating not just direct costs but all of SBR’s life-cycle 

costs; exploring alternatives for SBR if the new Transformational 

Communications Architecture (TCA), the infrastructure that is to help 

relay SBR data, falls short of its schedule and performance goals; and 

asking concept development contractors to propose multiple design 

concepts for SBR with or without TCA. Despite these accomplishments, 

however, decision makers will have significant knowledge gaps about 

SBR’s resources if SBR’s product development phase starts when 

currently planned. This is because DOD intends to start product 

development in fiscal year 2006 even though the two critical technologies 

that would enable the tracking of surface-moving targets and the timely 

delivery of imagery data will not have been tested in space or even in a 

relevant environment. Without the knowledge derived from such tests, 

DOD cannot adequately assess whether the technologies will work as 

intended, making it harder to reliably estimate how much time and money 

 1

 U.S. General Accounting Office, Military Space Operations: Common Problems and 

Their Effects on Satellite and Related Acquisitions, GAO-03-825R (Washington, D.C.: 

June 2, 2003). 

Results in Brief 
Page 5 GAO-04-759 Space-Based Radar 

is needed to complete development. Adding to SBR’s overall risk are 

uncertainties as to whether TCA will be available to transmit SBR’s vast 

volumes of radar data and imagery. Although DOD has plans underway to 

develop alternatives for SBR if TCA is delayed, the primary alternatives 

would involve either reducing SBR’s capabilities or significantly increasing 

program cost. Lastly, DOD and the Air Force may not have sufficient 

knowledge to make a corporate decision as to how much it should invest 

in space-based radar capabilities versus air-based capabilities at the time it 

makes a commitment to the formal SBR acquisition in 2006. While the Air 

Force has undertaken two analyses of the SBR investment, neither 

presents a comprehensive assessment as to whether space- or air-based 

radar platforms (or a combination of both) are better suited for tracking 

moving targets on land or at sea, nor does either analysis weigh the 

capabilities and costs of each suitable radar option in space and in the air. 

Before committing to SBR’s acquisition program in 2006, we recommend 

that senior-level officials in DOD and the intelligence community close 

gaps in the requirements-setting process in terms of documenting 

decisions and establishing a formal mechanism for addressing unresolved 

issues or how changes to approved requirements will be assessed. We 

recommend that DOD’s space acquisition policy be modified to identify 

the requirements-setting process when DOD partners with the intelligence 

community on space programs. We recommend that DOD delay approval 

to commit funding to product development for SBR until technologies are 

matured to higher levels, but if DOD determines that the SBR program 

should proceed to product development with less than mature 

technologies, we recommend that DOD be prepared to add time and 

money or make trade-offs with other DOD space programs to address 

SBR’s requirements and resources. DOD generally agreed with our 

findings and our recommendation to strengthen its study of SBR 

alternatives. DOD partially agreed with our recommendations to 

strengthen its requirement setting process for SBR and to demonstrate 

SBR technologies in a relevant or operational environment before 

committing to product development. DOD did not agree with our 

recommendation to modify its acquisition policy to strengthen 

requirements setting. In commenting on our recommendations, DOD cited 

concerns about supplanting current requirements setting processes. Our 

recommendation does not advocate replacing this process, but rather 

strengthening it to provide more transparency, discipline, and 

accountability. 
Page 6 GAO-04-759 Space-Based Radar 

SBR represents the first time that DOD has taken the lead on developing a 

major national security space capability with the intelligence community 

as a partner. Because of this partnership, SBR’s acquisition process is 

more complex than that used for typical DOD programs. While DOD and 

the intelligence community will likely use all the data that SBR produces, 

their priorities differ. DOD’s warfighting community is particularly 

interested in tracking targets moving over land or sea as well as other 

objects of interest. The intelligence community is more focused on 

obtaining detailed global imagery and combining it with other data for 

advanced processing. SBR is expected to meet both needs and be fully 

integrated with other space and non-space systems, including TCA, which 

is to transmit SBR’s data to receivers in the air, at sea, or on the ground. 

A key advantage of radar in space is having the ability to “see” 

through clouds and sand storms and any type of weather, day or night. 

Radar-equipped aircrafts, on the other hand, require U.S. air dominance to 

collect radar information and must steer clear of hostile areas—the result 

being limited radar coverage. The SBR concept offers other added 

features, including electronic steering of the radar signal toward a 

particular area and capturing high volumes of very fine resolution radar 

images of targets and terrain. With the ability to perform these functions 

almost simultaneously, SBR is expected to help analysts gain a better 

understanding of what is occurring in specific locations. 

To help meet some of its goals, DOD plans to leverage key technologies 

that were developed in the late 1990s to demonstrate a space-based radar 

capability. According to DOD officials, contractors developed some 

satellite hardware and prototype components under the Discoverer II 

program, which began in 1998 and was to identify and validate by 2008 the 

capability of tracking mobile ground targets from space. Discoverer II, 

comprising two radar demonstration satellites, was a joint initiative by the 

Air Force, DOD’s Defense Advanced Research Projects Agency, and the 

intelligence community’s National Reconnaissance Office. DOD officials 

told us that the Discoverer II program had reached the preliminary design 

review phase when it was cancelled in 2000 because of cost and schedule 

uncertainties, poorly explained requirements, and the lack of a coherent 

vision to transition the system to operational use. 

The Secretary of Defense concluded that space-based radar could provide 

a military advantage and in 2001 approved SBR as a new major defense 

acquisition program, delegating it to the Air Force. In July 2003, an 

independent cost assessment team consisting of representatives from 

DOD and the intelligence community estimated that $28.6 billion would be 

Background 
Page 7 GAO-04-759 Space-Based Radar 

needed to pay for SBR’s life-cycle costs—development, production, 

launch, and operation. The program entered the study phase in August 

2003. The Air Force has requested $328 million for SBR in fiscal year 2005 

and has programmed about $4 billion for the program from fiscal years 

2005 to 2009. Given concerns about affordability and readiness, the Fiscal 

Year 2005 Defense Appropriations Conference Report reduced funding for 

SBR to $75 million, with the direction to return this effort back to the 

technology development phase. In 2003, Congress reduced the Air Force’s 

$274 million budget request for SBR by $100 million due to concerns about 

technology maturity and schedule. DOD has scheduled the start of product 

development for mid-fiscal year 2006, with production starting at the end 

of fiscal year 2008 and the first satellite to be launched at the end of fiscal 

year 2012. Figure 1 shows SBR’s acquisition schedule in fiscal years. 

Figure 1: SBR’s Acquisition Schedule (in fiscal years) 

In the past several decades, DOD’s space acquisitions have experienced 

problems that have driven up costs by hundreds of millions, even billions, 

of dollars; have stretched schedules by years; and have increased 

performance risks. In some cases, capabilities have not been delivered to 

the warfighter after decades of development. Our reports have shown that 

these problems, common among many weapon acquisitions, are largely 

rooted in a failure to match the customer’s requirements (desired 

capabilities) with the developer’s resources (technical knowledge, timing, 

and funding) when starting an acquisition program. 

In particular, our past work has shown that for space systems, product 

development was often started based on a rigid set of requirements that 

proved to be unachievable within a reasonable development time frame. 

Other cases involved unstable requirements. In some cases where 

Gaining Knowledge 

about Requirements 

and Resources before 

Product Development 

Is Important for Space 

Acquisition Success 

Start of product 

development

(2006)

Start of 

production

(2008)

Sources: Air Force (data); GAO (analysis).

System

readiness

review

(2005)

System

design

review

(2005)

Preliminary

design

review

(2007)

Critical

design

review

(2008)

First SBR launch

(2012)

Start of 

study phase

(2003)
Page 8 GAO-04-759 Space-Based Radar 

requirements had been identified and approved, even more requirements 

were added after the program began. When technology did not perform as 

planned, adding resources in terms of time and money became the primary 

option for solving problems because the customer’s expectations about 

the product’s performance capabilities already had been set. 

The path traditionally taken by space programs—and other DOD weapon 

system programs—stands in sharp contrast to that taken by leading 

commercial firms. Our extensive body of work shows that leading 

companies use a product development model that helps reduce risks and 

increase knowledge when developing new products. This best practices 

model enables decision makers to be reasonably certain about their 

products at critical junctures during development and helps them make 

informed investment decisions. This knowledge-based process can be 

broken down into three cumulative knowledge points. 

• Knowledge point 1: A match must be made between the customer’s 

requirements and the developer’s available resources before product 

development starts. As noted earlier, DOD plans to start SBR product 

development in 2006. 

• Knowledge point 2: The product’s design must be stable and must meet 

performance requirements before initial manufacturing begins. 

• Knowledge point 3: The product must be producible within cost, schedule, 

and quality targets and demonstrated to be reliable before production 

begins. 

Systems engineering is a technical management tool that provides the 

knowledge necessary at knowledge point 1 to translate requirements into 

specific, achievable capabilities. With systems engineering knowledge in 

hand, acquisition decision makers and developers can work together to 

close gaps between requirements and available resources—well before 

product development starts. Some gaps can be resolved by the developer’s 

investments, while others can be closed by finding technical or design 

alternatives. Remaining gaps—capabilities the developer does not have or 

cannot get without increasing the price and timing of the product beyond 

what decision makers will accept—must be resolved through trade-offs 

and negotiations. Effective use of this tool enables decision makers to 

move on to knowledge point 2 and to produce a stable product design. 

DOD has recently issued a new acquisition policy for space systems, partly 

intended to address past acquisition problems and provide capability to 

users quicker. However, we recently reported that the policy is not likely 

to achieve these goals because it allows programs to continue to develop 
Page 9 GAO-04-759 Space-Based Radar 

technologies after product development starts. Our past work has shown 

that this approach makes it more difficult to estimate cost and schedule at 

the onset of product development and increases the likelihood that 

programs will encounter technical problems that could disrupt design and 

production and require more time and money to address than anticipated. 

Over the long run, the extra investment required to address these 

problems could reduce funding for developing other technological 

advances, slow the overall modernization effort, delay capabilities for the 

warfighter, and force unplanned—and possibly unnecessary—trade-offs 

between space and other weapon system programs. By contrast, DOD’s 

revised policy for other weapon acquisitions encourages programs to 

mature technologies to the point of being tested in an operational 

environment before beginning product development. We recommended 

that DOD modify its policy to separate technology development from 

product development so that needs can be matched with available 

technology, time, and money at the start of a new program. 

We also reported that DOD’s space acquisition policy does not require 

DOD to commit to setting aside funding for space acquisitions. Hence, 

there is no guarantee that the resources needed to meet requirements will 

be there on any individual program when needed. This makes it difficult 

for DOD as a whole to make corporate-level and trade-off decisions—

which will likely be needed when DOD begins the SBR acquisition because 

(1) costs are significantly increasing for other critical space systems such 

as the Space-Based Infrared System High, the Transformational Satellite, 

and the Evolved Expendable Launch Vehicle and (2) DOD is planning to 

undertake additional new programs, such as the Space-Based Space 

Surveillance system and a new version of the Global Positioning System. 

DOD is revising its new space acquisition policy partly to address these 

issues; however, the revision was not available for review at the time of 

this review. 

DOD has bolstered the SBR acquisition program by increasing senior 

leader and stakeholder involvement in setting requirements. However, 

DOD is not fully documenting commitments made during the requirements 

approval process before progressing to the next acquisition phase, nor has 

it established a process to resolve potential disagreements that may occur 

after approval. Clouding the approval of requirements is that DOD’s 

current space acquisition policy does not provide specific guidance for 

acquisitions that involve partnerships between DOD and the intelligence 

community. 

DOD Moving Forward 

on Acquiring Critical 

Knowledge but Gaps 

Remain in Approval 

for SBR Requirements 
Page 10 GAO-04-759 Space-Based Radar 

Providing senior-level oversight are three new groups created expressly 

for the SBR program: the Executive Steering Group, which advises the 

Requirements/Capabilities Group and the Joint Senior Acquisition Group. 

Members of these groups come from DOD, National Reconnaissance 

Office, and National Geospatial-Intelligence Agency. All key stakeholders 

are expected to have open and honest discussions about what can and 

cannot be done within desired time frames, budgetary constraints, and 

achievable technologies. Figure 2 shows how these groups work with 

SBR’s joint program office and requirements review boards for DOD and 

the intelligence community. 

SBR Managed by New 

Executive Oversight 

Structure 
Page 11 GAO-04-759 Space-Based Radar 

Figure 2: SBR’s Oversight Structure 

Sources: DOD (data); GAO (analysis). 

Senior officials from DOD, Air Force, other military services, National Reconnaissance 

Office, Joint Chiefs of Staff, Strategic Command, National Geospatial-Intelligence 

Agency, Defense Intelligence Agency, and others from the intelligence community

Executive Steering Group

Senior officials from many of the 

organizations represented in the Executive 

Steering Group, plus the Central Intelligence 

Agency and the Joint Program Office

Requirements/Capabilities Group

Senior officials from Air Force, other 

military services, National Reconnaissance 

Office, National Geospatial-Intelligence 

Agency

Joint Senior Acquisition Group

DOD’s Joint Joint Program Office

Requirements 

Oversight 

Council

Intelligence 

community’s 

Mission 

Requirements 

Board

Advise; set requirements;

assess cost, schedule,

risk

Advise Advise

Advise Advise Advise

Manage

Contractors

Advise; formally 

approve 

requirements,

sign documents

Legend

Newly created oversight groups

Existing groups
Page 12 GAO-04-759 Space-Based Radar 

A primary benefit of having an oversight structure for the SBR program, 

which involves many decision makers from across multiple organizations, 

is that the right people are involved in the decision-making process and 

can work together to lock in their requirements. The intent is to avoid 

problems of the past in which a program incurs cost, schedule, and 

performance risks because decision makers continue to negotiate and 

make trade-offs even after designers and engineers have started 

technology development and design work. Figure 3 shows the likely 

outcomes if requirements are poorly defined and are not approved or, in 

the case of SBR, if requirements are adequately defined and approved 

early in the study phase. 

Figure 3: Requirements-Setting Can Impact Acquisition Process 

Requirements not approved

Multiple players have competing requirements

Program office

Military services

Continual instability

requires more money,

more time

Navy

requirements

Army

requirements

Other

partners’

requirements

Testing

organizations’

requirements

Civilian

requirements

Contractors’

requirements

Technology development,

design, integration

Requirements Poorly Defined

Development proceeds with achievable requirements

SBR’s requirements are 

achievable and approved by 

all stakeholders

Technology development,

design, integration

SBR joint 

program office

Senior officials from DOD, 

military services, intelligence 

community

Stability results in better

money and time estimates

Requirements Adequately Defined

Source: GAO (analysis).
Page 13 GAO-04-759 Space-Based Radar 

DOD officials reported to us that the oversight groups have achieved 

informal consensus on requirements for SBR. However, this approval has 

not been formalized and it is unclear as to whether and how it might be 

formalized. Moreover, it is unclear how disagreements that may occur 

after initial approval will be resolved. 

Regardless of how many stakeholders have been invited to join in decision 

making or how much expertise is included in SBR’s oversight function, 

overall success of the SBR program hinges in part on whether the 

requirements are clear, stable, and achievable and whether DOD and the 

intelligence community demonstrate commitment and accountability by 

formally approving the requirements. In an acquisition decision 

memorandum, the Under Secretary of the Air Force requested that DOD 

and the intelligence community approve the initial capabilities document 

and concept of operations before the request for proposals was released in 

January 2004 for concept development contracts. DOD officials told us 

that the Joint Requirements Oversight Council and the intelligence 

community’s Mission Requirements Board approved the initial capabilities 

document, and there are memoranda documenting these decisions. The 

Joint Requirements Oversight Council reviewed the concept of operations, 

provided comments, but did not approve it. According to DOD officials, 

during a meeting of the SBR Executive Steering Group, high-level officials 

from the intelligence community verbally approved the concept of 

operations, but there is no documentation recording this approval. 

Agreement is critical because DOD and the intelligence community are 

placing different emphasis on desired capabilities for SBR. An 

independent assessment of the SBR program determined that 

requirements were adequate to enter the study phase, which started in 

August 2003, but cautioned that the requirements needed to be converged 

among all stakeholders and users. Table 1 shows the type of knowledge 

that decision makers expect to gain from the initial capabilities document 

and the concept of operations. 

SBR’s RequirementsSetting Process Lacks 

Formal Approval and 

Documentation 
Page 14 GAO-04-759 Space-Based Radar 

Table 1: Knowledge Provided by SBR’s Initial Capabilities Document and Concept 

of Operations 

Document Key knowledge provided 

Initial capabilities document Identifies current gaps in capability 

Identifies the overall desired capabilities of the SBR 

system 

Lists users’ performance requirements for SBR 

Identifies the functional relationships between users 

Specifies the desired capability for DOD’s capability 

development document, which is prepared at the end of 

the study phase 

Identifies validated requirements 

Concept of operations Describes the components of the SBR system 

Identifies how SBR information is to be processed and 

disseminated to the warfighters and others 

Describes how SBR fits into architectures involving other 

space and non-space systems in meeting requirements 

Identifies external threats to SBR and the perceived 

operational environment 

Sources: DOD (data); GAO (analysis). 

A defined requirements approval process helps decision makers resolve 

disagreements that may occur and ensure they will remain committed to 

their decisions after formal approval. Based on our past reports on 

uncovering problems and our best practice work, we believe that the steps 

in a formal approval process include: 

• explaining how decision makers’ requirements and comments are 

obtained and addressed; 

• identifying the officials and/or the organizations responsible for taking 

specific approval action; 

• establishing a mechanism and time frame for providing approval or 

disapproval; 

• establishing a system for addressing unresolved issues as they relate to 

key program documentation; and 

• assessing changes to approved requirements based on their effect on the 

program’s cost and schedule. 

While DOD has taken steps to increase senior leader and stakeholder 

involvement in setting requirements and addressing acquisition issues, 

DOD is not fully documenting commitments made during the requirements 

approval process, nor has it established a process to resolve potential 

disagreements that may occur after approval. 
Page 15 GAO-04-759 Space-Based Radar 

DOD is also taking positive steps to attain the knowledge needed to 

understand what resources will be needed to develop SBR’s capabilities 

and to mitigate risks. These include: 

• relying on systems engineering to translate requirements into specific, 

achievable capabilities and to close gaps between requirements and 

resources; 

• adopting a more comprehensive cost estimating technique to identify 

SBR’s life-cycle costs; 

• exploring alternatives for SBR if TCA—the infrastructure that DOD is 

depending on to transmit SBR’s data—incurs schedule slips; and 

• asking two concept development contractors to each propose at least two 

different operations concepts for SBR with and without TCA. 

However, the path that SBR is on has potential for knowledge gaps when 

making investment decisions, the types of gaps that have hampered other 

space programs in the past. Specifically, it is expected that some critical 

SBR technologies will not be mature when product development starts, 

that is, not tested in a relevant or operational environment. Typical 

outcomes of this lack of knowledge are significant cost and schedule 

increases because of the need to fix problems later in development. 

Furthermore, TCA, a new, more robust communications infrastructure 

that could transmit SBR’s imagery data much more quickly than the 

current infrastructure, is facing uncertainties. Specifically, one of TCA’s 

primary components, the Transformational Satellite, may not be ready in 

time to support SBR.2

 Without mature technologies and faced with a 

possible slip in the Transformational Satellite’s schedule, DOD will be less 

able to accurately estimate total system costs before the start of product 

development. In addition, DOD and the Air Force may not have knowledge 

needed to make corporate level trade-offs between SBR and other 

air-based radar systems at the time it plans to make a commitment to 

invest in the SBR acquisition program. DOD has undertaken an analysis to 

weigh the merits of space-based radar. At this time, it is not known 

whether this analysis will be a detailed examination of the capabilities and 

costs of each individual radar option and combined with other radar 

platforms or whether the analysis will be a less rigorous examination of 

the mix of radar options. 

 2

 U.S. General Accounting Office, Space Acquisitions: Committing Prematurely to 

the Transformational Satellite Program Elevates Risks for Poor Cost, Schedule, and 

Performance Outcomes, GAO-04-71R (Washington, D.C.: Dec. 4, 2003). 

DOD Taking Proactive 

Steps to Gain 

Knowledge about 

Resources, but 

Critical Gaps May 

Remain at Product 

Development 
Page 16 GAO-04-759 Space-Based Radar 

DOD is planning to aggressively address technology, affordability, and 

integration issues by, in part, instituting robust systems engineering 

processes and procedures. Systems engineering is a technical management 

tool for gaining information on a broad array of activities related to the 

development of a system. For SBR, DOD plans to perform systems 

engineering work on requirements and their allocation, interface 

definitions, trade studies, risk management, performance analysis and 

modeling, environmental and safety planning, test planning, program 

protection planning, information assurance, and configuration control. 

Applying systems engineering to these activities would give DOD the 

insight and knowledge it needs to better manage the program, including 

ways to reduce risk and ensure the viability of concepts and requirements. 

DOD has also decided to take a more comprehensive approach to 

estimating SBR’s life-cycle costs. According to the SBR program director, 

this marks the first time DOD has willingly presented all related costs to 

develop, acquire, produce, maintain, operate, and sustain the system. DOD 

officials stated that they wanted to identify not just direct costs, but also 

costs for associated infrastructure such as the costs related to modifying 

the ground system that will be used to support SBR as well as other 

systems. According to DOD, about $8 billion of the $28.6 billion life-cycle 

cost estimate represents costs that in the past, would not have been 

included in space program total cost estimates. Taking steps to more 

comprehensively identify SBR and SBR related costs is a positive step and 

will help DOD manage its portfolio of space programs. 

Although DOD hopes to rely on TCA to support SBR data transmissions, it 

is taking a proactive approach to identify and assess the viability of TCA 

alternatives. First, in April 2004, DOD awarded two 2-year contracts for 

concept development efforts that call for the identification of alternatives 

to TCA. For each alternative identified, the contractor is to conduct an 

assessment of the cost, risk, and effect on SBR’s performance. DOD 

officials told us that when SBR initiates product development in 2006, it 

would know whether TCA will be available to support SBR or whether to 

pursue a TCA alternative. In addition, DOD also awarded two contracts 

totaling $510,000 for a yearlong study to propose several alternatives to 

TCA capable of supporting SBR’s communications requirements and to 

analyze the viability of such alternatives. These actions have put DOD in a 

better position to ensure the program is successful. 

The two 2-year contracts that DOD awarded in April 2004 also require that 

at least two different viable SBR operations concepts be proposed. DOD is 

expecting each contractor to fully develop the alternative operations 

DOD Taking Positive 

Steps to Build Foundation 

of Knowledge about 

SBR Resources 
Page 17 GAO-04-759 Space-Based Radar 

concepts. These alternative concepts could involve using unique radar 

processing techniques. According to DOD, it will work with each of the 

contractors to pare down the alternatives to a single best concept for each 

contractor. For the remainder of the contract performance period, the 

contractors would focus their attention on fleshing out the details 

associated with these concepts. This approach will put DOD in a better 

position when the time comes to select a single contractor to design the 

SBR system. 

DOD officials have said that SBR will likely be the most technically 

challenging, software-intensive, and complex space system ever built by 

DOD. The two key pieces of hardware needed to give SBR a radar 

capability from space—the electronically scanned array (which steers the 

radar signal to an area of interest) and the on-board processor (the 

radar-processing unit aboard SBR)—face the highest amount of risk. The 

electronically scanned array can scan multiple areas of interest virtually 

simultaneously, allowing for simplified satellite design over conventional 

technology offering mechanical slew radar. The on-board processor is 

expected to allow the processing radar data to assure the timely and 

thorough delivery of imagery data that will be downlinked for 

transmission to the warfighter. 

To minimize the potential for technology development problems after the 

start of product development, DOD uses an analytical tool to assess 

technology maturity for many weapon system acquisition programs. 

Called Technology Readiness Levels (TRL), this tool associates a TRL with 

different levels of demonstrated performance, ranging from paper studies 

to actual application of the technology in its final form. The value of using 

a tool based on demonstrated performance is that it can presage the likely 

consequences of incorporating a technology at a given level of maturity 

into a product’s development, enabling decision makers to make informed 

choices. Our previous reviews have found the use of TRLs, which range 

from 1 to 9, to be a best practice. (See app. I for a description of the 

TRL levels.) 

The critical technologies that will support the SBR program currently 

range from TRL 3 to 5. A TRL 3 means that most of the work performed so 

far has been based on analytical and laboratory studies. At a TRL 5, the 

basic technology components are integrated and tested in a simulated or 

laboratory environment. Table 2 shows the current TRL for each of SBR’s 

critical technologies and the expected TRL at product development start 

in 2006. In general, the program office’s key risk reduction efforts are 

Technologies Will Not Be 

Mature at Product 

Development Start 
Page 18 GAO-04-759 Space-Based Radar 

scheduled to mature these technologies to TRL 5 by the middle of 

fiscal year 2006. These efforts include the awarding of research and 

development contracts to three payload contractors for efforts to continue 

to develop and mature these components (the electronically scanned array 

and on-board processor). The period of performance of each contract is 

about 2.5 years. 

Table 2: Technology Readiness Levels of SBR Critical Technologies 

Critical technology 

Current TRL 

levela

Expected TRL 

level

Fiscal 

yearb

Electronically scanned array 4 5 2006

On-board processor 3 5 2006

Signal processing algorithms (for moving 

target indication) 4-5 5 2006

Information management system 3 5 2006

Moving target indication exploitation 

hardware and software 3-4 5 2006

Sources: DOD (data); GAO (analysis). 

a

A TRL range is shown because of varying maturities between the viable suppliers. 

b

Even if the SBR program office chooses to pursue a different SBR concept alternative, these 

technologies still would be considered critical; however, the specific technology readiness date could 

be different for each proposed alternative. 

To mature the electronically scanned array and on-board processor 

technologies from a TRL 3/4 to 5, the contractors plan to conduct various 

developmental and integrative tasks in about 3 years. For example, one 

contractor plans to conduct 18 tasks to develop the electronically scanned 

array and 8 tasks to integrate the on-board processor with other system 

components. In addition, the development of the integrated circuits and 

programmable microcircuits that support the on-board processor 

requires extensive tests and evaluations and the radiation-hardening 

requirement further complicates the development. Given the challenges 

of the state-of-the-art technologies being developed and the algorithms 

involved, the testing programs must be rigorous and transparent and the 

results fully documented. We have determined that the time allotted to 

mature the SBR technologies to TRL 5 is ambitious given the tasks that 

need to be accomplished. Furthermore, the development of the signal 

processing algorithms and communications downlink involves significant 

software development. Based on our past experience of software 

assessments in other programs, the establishment of a structured testing 

regime for software development has always been underestimated. 
Page 19 GAO-04-759 Space-Based Radar 

By planning to start product development in fiscal year 2006 with 

technologies at TRL 5, DOD is very likely to continue designing the 

system and to conduct other program activities at the same time it 

builds representative models of key technologies and tests them in an 

environment that simulates space conditions (such as a vacuum chamber). 

This approach is common with DOD space acquisitions but has a 

problematic history. Our past work3

 has shown that it can lead to 

significant cost and schedule increases because of the need to fix 

problems later in development. A continuing problem is that software 

needs are poorly understood at the beginning of a program. We have 

previously recommended that DOD not allow technologies to enter into a 

weapon system’s product development until they are assessed at a TRL 7, 

meaning a prototype has been demonstrated in an operational 

environment.4

 DOD has accepted lower TRL thresholds for space 

programs because testing in an operational environment—in space, for 

example, or even in a relevant environment—is difficult and costly. 

However, DOD’s new space acquisition policy does not identify what the 

minimum TRL level should be before starting product development for 

space programs, how risks should be mitigated if technologies are 

included in programs without full testing, or how lower TRL levels affect 

the confidence of cost and schedule estimates. Moreover, the policy does 

not address the option of maturing technologies outside a program and 

pulling them in once they prove to be viable. 

One way to mitigate technology risk is to rely on backup technologies, 

should newer technologies prove to be problematic during product 

development. According to DOD officials, there are backup technologies 

that are more mature for each of SBR’s critical technologies. The backups 

are the same technologies but rely on a previous and more mature version. 

Using previous versions of these technologies would result in a lower level 

of desired performance—such as a reduced area collection rate, a 

reduction in the total number of targets collected per satellite per day, 

increased product delivery time frames to the user, an increased weight of 

the spacecraft, and higher cost. For example, more mature versions of the 

 3

 U.S. General Accounting Office, Military Space Operations: Common Problems and 

Their Effects on Satellite and Related Acquisitions, GAO-03-825R (Washington, D.C.: 

June 2, 2003). 

4

 U.S. General Accounting Office, Best Practices: Better Management of Technology 

Development Can Improve Weapon System Outcomes, GAO/NSIAD-99-162

(Washington, D.C.: July 30, 1999). 
Page 20 GAO-04-759 Space-Based Radar 

electronically scanned array exist and if used, would result in a reduction 

in its performance level. In addition, some previous versions of SBR 

technologies have not been demonstrated or tested in space. But 

according to DOD officials, even with backup technologies, the total 

performance of the SBR system can be maintained through systems 

engineering trades. DOD says it has been able to leverage some of the key 

technologies (such as the electronically scanned array) that were under 

development during the previous effort, Discoverer II, to demonstrate a 

space-based radar capability. 

Current plans call for TCA to transmit SBR’s large volume of data to 

ground-, air-, ship-, and space-based systems. However, one of TCA’s 

primary components, the Transformational Satellite—which will use 

technologies that DOD has never before tried in space—is facing 

uncertainties in its scheduled 2011 launch. DOD started product 

development for the Transformational Satellite in December 2003 even 

though technologies were immature. If the Transformational Satellite 

falters but SBR launches as expected in 2012, then DOD will have a fully 

operational, new-generation satellite that is missing its primary means of 

data transmission. Recognizing the challenges, DOD is to decide by 

November 2004 whether to move forward or delay the Transformational 

Satellite’s acquisition program and instead procure another Advanced 

Extremely High Frequency satellite, which already are under development 

and are based on mature technologies. 

Our analysis shows that alternatives to TCA may involve a greater reliance 

on processing aboard the SBR satellites, thereby increasing software 

development efforts. This approach would reduce the volume of data 

requiring transmission, allowing conventional satellite systems, such as 

the Advanced Extremely High Frequency satellites, to handle the 

transmission. Another likely alternative is to have SBR satellites transmit 

only selected portions of data, again, so that the Advanced Extremely High 

Frequency satellite could handle the lower volume of information. Finally, 

a dedicated system of satellites could be fielded for the sole purpose of 

transmitting SBR data, significantly increasing program cost and raising 

affordability issues. Currently, DOD is working closely with officials from 

the Transformational Satellite program office to evaluate the relative 

merits of various alternatives and to document the interfaces needed 

between SBR and the Transformational Satellite for each alternative. 

During the course of our audit work, SBR program officials met weekly 

with the Transformational Satellite program’s integrated product teams 

and were coordinating efforts on a memorandum of agreement on 

Communications 

Infrastructure May Not 

Be Ready in Time to 

Support SBR 
Page 21 GAO-04-759 Space-Based Radar 

requirements development, joint engineering practices, and studies of 

air- and space-based options. 

Based on a notional constellation of nine (plus one spare) satellites 

operating in low-earth orbit, an independent cost assessment in 2003 put 

SBR’s cost at the $28.6 billion mark, making SBR the most expensive DOD 

space system ever built. When this initial cost estimate is revised in 2006, 

before SBR’s product development starts, DOD is to have decided a 

number of issues, such as how many satellites are to be acquired, what 

their capabilities will be, and at what altitude(s) the satellites are to 

operate. This system refinement allows DOD to develop a more realistic 

total system cost estimate—a critical knowledge point if a successful 

match between requirements and resources is to be made. However, if 

DOD begins product development with less than mature technologies and 

without knowing the availability of TCA, accurate cost estimates for SBR 

will be much more difficult to prepare. We have previously reported that 

improving the reliability of cost estimates is critical5

 and affords DOD 

decision makers with the appropriate information to decide whether a 

weapon system is worth the overall investment and whether the time is 

right to proceed with such an investment. Once a total cost is known, DOD 

needs to secure the funding so it can design, produce, operate, and sustain 

the system. 

DOD may also lack knowledge needed to make a corporate-level decision 

as to how much it should invest in SBR versus air platforms with similar 

capabilities at the time it begins the SBR acquisition program. In 

November 2003, the Air Force completed an analysis of alternatives (AOA) 

for SBR, which was supposed to evaluate whether space- or air-based 

radar platforms (such as manned and unmanned aircraft with radar 

capabilities) or a combination of both are better suited for tracking 

moving targets on land or at sea and analyze the capabilities and costs of 

each suitable option. However, DOD officials raised a concern that the 

AOA only weighed the merits of various space-based solutions. The Air 

Force decided to undertake a follow-on study to explore the optimal ways 

to gather information on ground moving targets from radars based in 

space versus air. The plan is to also use this follow-on study as part of 

DOD’s preparations for submitting a fiscal year 2006 budget to Congress to 

 5

 U.S. General Accounting Office, Defense Acquisitions: Improvements Needed in Space 

Systems Acquisition Management Policy, GAO-03-1073 (Washington, D.C.: Sept. 15, 2003). 

SBR’s Cost Estimate 

Unlikely to Be Realistic 

Because of Multiple 

Uncertainties 
Page 22 GAO-04-759 Space-Based Radar 

secure funding for SBR and other radar systems on air platforms. A more 

thorough AOA, completed before the start of the study phase, might 

conceivably have determined that air-based radar could provide many or 

most of the capabilities promised by space-based radar but at a fraction of 

the cost. Moreover, this type of analysis could help DOD officials better 

decide whether SBR should be initiated at a later date, when critical 

technologies will have been matured, or when the communications 

infrastructure to support SBR will be available. 

DOD officials have mentioned other ongoing studies that are examining 

the optimal mix between SBR and other platforms for specific capabilities, 

such as ground-moving target indication. However, it is unclear as to the 

extent these studies will be factored into the SBR product development 

start decision. 

DOD has recently embarked on a discovery and exploration phase for its 

SBR program. During this period, it is critical for programs to work toward 

closing knowledge gaps about requirements, technologies, funding, and 

other resources so they can be positioned to succeed when DOD decides 

to commit to making significant investments. For SBR, this would mean 

testing technologies to the point of knowing they can work as intended 

before starting program development, securing agreement on 

requirements with the intelligence community, and fully assessing the 

cost and benefits and risks of relying on TCA and alternatives, including 

different mixes of air and space-based platforms. DOD is taking positive 

steps toward this end, but without maturing critical technologies or 

securing formal commitment on requirements, it will not be able to assure 

decision makers that the program can be completed within cost and 

schedule estimates. Should DOD decide to proceed on a path that leaves 

open important questions, including those about technologies, then it 

should do so with (1) assessments of technical risks and what additional 

resources (in terms of time and money) would be needed to address 

problems that may occur during development as well as what trade-offs 

would need to be made with other space programs should DOD need to 

invest additional resources in SBR, and (2) a formal commitment for 

providing additional resources if problems do occur. 

Conclusions 
Page 23 GAO-04-759 Space-Based Radar 

To better ensure that DOD and its intelligence community partners obtain 

the additional knowledge they need to determine whether and when to 

begin the SBR acquisition program, we recommend that the Secretary of 

Defense direct the Under Secretary of the Air Force to: 

• Direct the SBR Executive Steering Group to ensure that outcomes from 

the requirements management process are formally approved and 

documented as the program proceeds through product development 

before an investment is made beyond technology and concept 

development for the SBR program. This group should identify how key 

document review comments are to be obtained and addressed and identify 

all the officials and/or organizations responsible for taking specific 

approval action. In addition, the group should establish a mechanism and 

time frame for providing approval/disapproval. Finally, the group should 

establish a formal mechanism for addressing unresolved issues as they 

relate to key program documentation, as well as how changes to approved 

requirements will be assessed. 

• Modify DOD’s space acquisition policy to reflect protocols for setting 

requirements when DOD undertakes programs in partnership with the 

intelligence community. 

• Delay approval to commit funding to product development (key decision 

point B) for SBR until technologies have been demonstrated in a relevant 

or operational environment so DOD can more reliably estimate the 

resources needed to complete the program. If the Under Secretary 

determines that the program should go forward with less mature 

technologies, then we recommend that the Under Secretary (1) undertake 

an assessment of the backup technologies that may lessen capability and 

add cost to the program and the additional time and money that may be 

required to meet SBR’s performance objectives to address those risks, 

(2) undertake an assessment of trade-offs that may need to be made with 

other space programs to assure SBR’s successful outcome, and (3) secure 

formal commitments from DOD to provide funding for total estimated 

costs as well as costs estimated to address potential technical risks. 

• Strengthen the ongoing study of options for tracking ground-moving 

targets by ensuring this work includes: (1) a full range of air and space 

options; (2) measures of effectiveness that would help justify choosing 

SBR over air options; and (3) the possibility of having to rely on TCA 

alternatives for space options. This work should also consider the results 

of analyses being conducted by other DOD entities on tracking groundmoving targets. 

Recommendations for 

Executive Action 
Page 24 GAO-04-759 Space-Based Radar 

We received written comments on a draft of this report from the Deputy 

Under Secretary of Defense (Programs, Requirements, and Resources) 

within the Office of the Under Secretary of Defense for Intelligence. 

DOD generally agreed with our findings and our recommendation to 

strengthen its study of SBR alternatives. DOD partially agreed with our 

recommendations to strengthen its requirement setting process for SBR 

and to demonstrate SBR technologies in a relevant or operational 

environment before committing to product development. DOD did not 

agree with our recommendation to modify its acquisition policy to 

strengthen requirements setting. 

In commenting on our recommendations, DOD agreed in principle with 

the need to extensively define, analyze, and validate requirements for SBR, 

but it did not believe this necessitated a different requirements setting 

process than the one that is in place for SBR or changes to its space 

acquisition policy or that additional controls were needed within the 

program’s study phase. To clarify, our recommendation was not intended 

to construct a new requirements setting process or supplant activities 

undertaken by the Joint Requirements Oversight Council or the Mission 

Requirements Board, as DOD asserts. Rather, we recommend that DOD 

build on the positive requirements setting procedures it has already put in 

place by instituting controls and mechanisms that ensure transparency, 

discipline, and accountability with requirements setting. As noted in our 

report, while DOD has taken steps to increase senior leader and 

stakeholder involvement in requirements setting, it is not fully 

documenting commitments made during the requirements approval 

process, nor has it established a process to resolve potential 

disagreements that may occur after approval. It is important that this 

discipline be instilled in the study phase and throughout the SBR effort. As 

noted in previous reports, many space programs have not been executed 

within cost and schedule estimates because of an inability to establish firm 

requirements and to make and enforce trade-off decisions. For SBR, the 

potential for difficulty in requirements setting is higher because of the 

distinct needs of the intelligence community and DOD’s desire to integrate 

SBR with other radar platforms. Moreover, revising the acquisition policy 

to clearly communicate protocols that should be followed when DOD 

undertakes space programs in the future involving diverse users—such as 

the intelligence community, military services, industry, and/or other 

agencies—would further help DOD to rationalize requirements setting and 

to solidify relationships with users, which DOD reported was a top SBR 

management issue. 

Agency Comments 

and Our Evaluation 
Page 25 GAO-04-759 Space-Based Radar 

In regard to our recommendation to delay product development until SBR 

technologies are sufficiently matured, DOD stated that it has planned for 

critical and most other enabling technologies to be demonstrated at least 

at the component level in a relevant environment on the ground. DOD also 

stated that where technically feasible and fiscally feasible, it planned to 

pursue on-orbit demonstrations. It also stated it has taken some actions 

relating to our recommendation such as accounting for technical risks in 

the costing and budgeting process. DOD asserted, however, that our 

recommendation encourages pursuit of older, more proven, technologies. 

We recommended that DOD pursue relevant or operational environment 

demonstrations of all critical technologies and even an integrated system 

before committing to a formal acquisition program because this practice 

enables a program to align customer expectations with resources, and 

therefore minimize problems that could hurt a program in its design and 

production phase and drive up costs and schedule. Further, we agree that 

continuing to develop leading edge technology is important for space 

system capabilities. However, history has shown and we have repeatedly 

reported that conducting technology development within a product 

environment consistently delays the delivery of capability to the user, robs 

other programs of necessary funds through unanticipated cost overruns, 

and, consequently, can result in money wasted and fewer units produced 

than originally stated as necessary. A technology development 

environment is more forgiving and less costly than a delivery-oriented 

acquisition program environment. Events such as test “failures,” new 

discoveries, and time spent in attaining knowledge are considered normal 

in this environment. Further, judgments of technology maturity have 

proven to be insufficient as the basis for accurate estimates of program 

risks as it relates to cost, schedule, and capability. Lastly, our report noted 

that DOD was taking positive actions to gain knowledge about technology 

readiness, including strengthening systems engineering, undertaking risk 

assessments, and assessing various technical concepts. Given the potential 

cost of the program, our recommendation focuses on taking these steps 

further by assessing what trade-offs may need to be made with other space 

programs should the program encounter technical problems that require 

more time and money than anticipated and securing commitments to 

provide resources needed to address such problems. 

DOD’s detailed comments are provided in appendix II. 

We plan to provide copies of this report to the Secretary of Defense, the 

Secretary of the Air Force, and interested congressional committees. 
Page 26 GAO-04-759 Space-Based Radar 

We will make copies available to others upon request. In addition, the 

report will be available on the GAO Web site at http://www.gao.gov. 

If you or your staff has any questions concerning this report, please 

contact me at (202) 512-4841 or Arthur Gallegos at (303) 572-7368. Other 

key contributors to the report include Tony Beckham, Cristina Chaplain, 

Lily Chin, Maria Durant, Nancy Rothlisberger, and Hai V. Tran. 

Katherine V. Schinasi 

Managing Director 

Acquisition and Sourcing Management 
Appendix I: TRL Scale for Assessing Critical 

Technologies 

Page 27 GAO-04-759 Space-Based Radar 

TRL TRL description 

Basic principles observed and reported Lowest level of technology readiness. Scientific research begins to be translated 

into applied research and development (R&D). Examples might include paper 

studies. 

Technology concept and/or application 

formulated 

Invention begins. Once basic principles are observed, practical applications can be 

invented. Examples are still limited to paper studies. 

Analytical and experimental critical function 

and/or characteristic proof of concept 

Active R&D is initiated. This includes analytical studies and laboratory studies to 

physically validate analytical predictions of separate elements of the technology. 

Examples include components that are not yet integrated or representative. 

Component and/or breadboard validation in 

laboratory environment 

Basic technological components are integrated to establish that they will work 

together. This is relatively “low fidelity” compared to the eventual system. Examples 

include integration of “ad hoc” hardware in a laboratory. 

Component and/or breadboard validation in 

relevant environment 

Fidelity of breadboard technology increases significantly. Basic technological 

components are integrated with reasonably realistic supporting elements so that the 

technology can be tested in simulated environment. Examples include “high fidelity” 

laboratory integration of components. 

System/subsystem model or prototype 

demonstration in a relevant environment 

Representative model or prototype system, which is well beyond the breadboard 

tested for level 5, is tested in a relevant environment. Represents a major step up in 

a technology’s demonstrated readiness. Examples include testing a prototype in a 

high-fidelity laboratory environment or in a simulated operational environment. 

System prototype demonstration in an 

operational environment 

Prototype near, or at, planned operational system. Represents a major step up from 

TRL 6, requiring demonstration of an actual system prototype in an operational 

environment such as an aircraft, vehicle, or space. 

Actual system completed and qualified through 

test and demonstration 

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 system to determine if it meets design specifications. 

Actual system proven through successful 

mission operations 

Actual application of the technology in its final form and under mission conditions, 

such as those encountered in Operational Test and Evaluation. Examples include 

using the system under operational mission conditions. 

Source: DOD Interim Defense Acquisition Guidebook, app.6 (Oct. 30, 2002). 

Appendix I: TRL Scale for Assessing Critical 

Technologies 
Appendix II: Comments from the Department 

of Defense 

Page 28 GAO-04-759 Space-Based Radar 

Appendix II: Comments from the Department 

of Defense 

Note: GAO comments 

supplementing those in 

the report text appear at 

the end of this appendix. 
Appendix II: Comments from the Department 

of Defense 

Page 29 GAO-04-759 Space-Based Radar 
Appendix II: Comments from the Department 

of Defense 

Page 30 GAO-04-759 Space-Based Radar 

Note: Page numbers in 

the draft report may differ 

from those in this report. 
Appendix II: Comments from the Department 

of Defense 

Page 31 GAO-04-759 Space-Based Radar 

See comment 2. 

See comment 1. 

Now on p. 23. 
Appendix II: Comments from the Department 

of Defense 

Page 32 GAO-04-759 Space-Based Radar 
Appendix II: Comments from the Department 

of Defense 

Page 33 GAO-04-759 Space-Based Radar 

Now on p. 18. 

See comment 3. 

Now on p. 23. 
Appendix II: Comments from the Department 

of Defense 

Page 34 GAO-04-759 Space-Based Radar 
Appendix II: Comments from the Department 

of Defense 

Page 35 GAO-04-759 Space-Based Radar 

Now on p. 23. 
Appendix II: Comments from the Department 

of Defense 

Page 36 GAO-04-759 Space-Based Radar 
Appendix II: Comments from 

the Department of Defense 

Page 37 GAO-04-759 Space-Based Radar 

The following are GAO’s comments on the Department of Defense’s letter 

dated June 29, 2004. 

1. DOD stated that DOD does not require formal approval for the 

concepts of operations from the Joint Requirements Oversight Council 

or the Mission Requirements Board, but noted that the Joint 

Requirements Oversight Council communicated agreement in a memo. 

As we reported, the Under Secretary of the Air Force requested that 

both DOD and the intelligence community approve the initial 

capabilities document and concept of operations in light of the 

complexity of SBR’s acquisition process, the partnership with the 

intelligence community, and the proposed integration with other radar 

platforms. 

2. DOD stated that it is not engaged in a partnership with the intelligence 

community on SBR, as our report states. Specifically, DOD stated that 

SBR is wholly funded in the defense budget and that a programmatic 

commitment with the intelligence community does not exist. DOD’s 

SBR System Acquisition Strategy was signed by senior-level officials 

from DOD, National Reconnaissance Office, and the National 

Geospatial-Intelligence Agency and approved on January 14, 2004. This 

strategy states that the Air Force, in close partnership with the 

National Reconnaissance Office and National Geospatial-Intelligence 

Agency, is responsible for leading development of an SBR capability. 

This strategy further identifies the responsibilities related to SBR that 

each mission partner (National Reconnaissance Office and National 

Geospatial-Intelligence Agency) is supposed to carry out. We disagree 

with DOD’s assertion that these organizations must provide funding to 

SBR in order to consummate a partnership. Because SBR is being 

justified on the basis of the system’s ability to provide intelligence, 

surveillance, and reconnaissance products to both DOD and the 

intelligence community, the part of the budget used is not relevant to 

our finding. 

3. To clarify, we did not recommend that DOD pursue lower risk 

technologies that would result in lower levels of desired performance. 

Instead, we reported that DOD might have to resort to using backup 

technologies if the current ones prove to be problematic during 

product development. We recommended that DOD should assess the 

cost to the program of having to use the backup technologies DOD has 

already identified in terms of time and money.

GAO’s Comments 

(120267) 
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