Page i GAO-19-456T Defense Acquisitions

DEFENSE 

ACQUISITIONS

Observations on the 

F-35 and Air Force's 

Advanced Battle 

Management System

Statement of Michael J. Sullivan, Director 

Contracting and National Security Acquisitions

Testimony 

Before the Subcommittee on Tactical Air 

and Land Forces, Committee on Armed 

Services, House of Representatives

For Release on Delivery 

Expected at 9:00 a.m. ET

Thursday, May 2, 2019

GAO-19-456T

United States Government Accountability Office
______________________________________ United States Government Accountability Office

May 2, 2019

DEFENSE ACQUISITIONS

Observations on the F-35 and Air Force's Advanced 

Battle Management System

What GAO Found

The Department of Defense (DOD) wrapped up the F-35 development program 

in April 2018 and expects to complete operational testing in December 2019. 

DOD has turned its attention to modernization efforts—referred to as Block 4—to 

add new capabilities to address evolving threats. The program office estimates

Block 4 to cost at least $10.5 billion through 2024. DOD plans to start Block 4 

development without a complete business case identifying baseline cost and 

schedule estimates. Key documents for establishing a business case, such as an 

independent cost estimate, will not be ready before the program plans to award 

Block 4 development contracts in May 2019 (see figure). 

Three F-35 Modernization Business Case Documents That Will Not Be Ready Before the 

Planned Development Contract Awards

Without a business case—consistent with acquisition best practices—program 

officials cannot be confident that the risk of committing to development has been 

reduced adequately prior to planned contract awards. 

The program made slow, sustained progress in improving the F-35’s reliability 

and maintainability (R&M). F-35 aircraft are assessed against eight R&M metrics, 

which inform how much time the aircraft will be in maintenance rather than 

operations. Half of these metrics are not meeting targets. While the program 

office has a plan for improving R&M, its guidance is not in line with GAO’s 

acquisition best practices or internal control standards as it does not include 

specific, measurable objectives, align improvement projects to meet those 

objectives, and prioritize funding to match resources to R&M requirements. If the 

R&M requirements are not met, the warfighter will have to settle for a less 

reliable and more costly aircraft than originally planned. This contributes to the F35’s $1.12 trillion estimated sustainment costs and challenges with maintaining 

an expanding fleet that also has supply chain and logistics system problems.

GAO’s ongoing work indicates that the Air Force’s Advanced Battle Management 

System (ABMS)—intended to provide battle management command and control 

and surveillance across air, land, and sea—is in the early stages of planning. 

The capabilities and the strategy to deliver those capabilities are still to be 

determined. The Air Force plans to manage ABMS as a family of systems, 

integrating sensors from existing and future weapons programs, and overseen by 

a Chief Architect—whose role is still to be determined. The Air Force expects to 

further define ABMS after analyzing different options for delivering the capability. 

That analysis is expected to be complete in summer 2019.

Why GAO Did This Study

In 2018, the F-35 program began 

operational testing. Also in 2018, the Air 

Force continued planning for the 

acquisition of ABMS, intended to 

modernize how DOD maintains 

command and control over and 

manages the future battlefield. Both the 

F-35 and ABMS are expected to play 

key roles in DOD’s modernization 

efforts.

This testimony statement discusses (1) 

the F-35 program’s development and 

modernization efforts, and progress in 

improving the aircraft’s R&M and (2) 

DOD’s current planning efforts for 

ABMS. This statement is based on two 

GAO reports on the F-35 published in

April 2019 and on GAO’s ongoing work 

examining ABMS. To conduct this work, 

GAO analyzed DOD management 

reports; discussed the efforts with 

program and contractor officials; and 

compared both efforts to DOD policy

and GAO acquisition best practices.

What GAO Recommends

In April 2019, GAO recommended that 

the F-35 program office complete its 

Block 4 business case before making 

more contract awards. DOD did not 

concur, citing that it has adequate 

knowledge to begin Block 4 

development. GAO maintains that 

completing its business case before 

awarding its Block 4 development 

contracts would put DOD and the 

program in a better position to 

successfully develop Block 4 

capabilities. GAO also recommended

that DOD take action to improve its 

R&M performance. DOD concurred and 

noted the actions it would take.

View GAO-19-456T. For more information, 

contact Michael J. Sullivan at (202) 512-4841 or 

sullivanm@gao.gov.

Highlights of GAO-19-456T, a testimony before 

the Subcommittee on Tactical Air and Land 

Forces, Committee on Armed Services, House 

of Representatives
Page 1 GAO-19-456T Defense Acquisitions

Chairman Norcross, Ranking Member Hartzler, and Members of the 

Subcommittee:

Thank you for the opportunity to discuss our work on the F-35 Lightning II 

program and the Air Force’s Advanced Battle Management System 

(ABMS). The Department of Defense’s (DOD) 2018 National Defense 

Strategy outlines its strategic approach to build a more lethal force, which 

includes modernizing key capabilities to address future threats. Both the 

F-35 and the ABMS are expected to play a key role in DOD’s 

modernization efforts.

DOD is now in its 18th year of developing the F-35—a family of fifthgeneration strike fighter aircraft for the United States Air Force, Marine 

Corps, and Navy, as well as eight international partners.1 The F-35 

program has developed and is delivering three variants; the F-35A 

conventional takeoff and landing variant for the Air Force, the F-35B short 

takeoff and vertical landing variant for the Marine Corps, and the F-35C 

carrier-suitable variant for the Navy. The F-35 is DOD’s largest acquisition 

program in U.S. military history, with total acquisition costs expected to 

exceed $406 billion to develop and procure more than 2,400 aircraft 

through fiscal year 2044. In addition, the Office of the Secretary of 

Defense’s (OSD) Cost Assessment and Program Evaluation office 

estimates the F-35 program’s sustainment costs to operate and maintain 

the fleet over the next 52 years to be $1.12 trillion.

ABMS is in the early planning stages and is intended to change the way 

the Air Force provides battle management command and control 

capabilities across air, land, sea, and space. ABMS would shift the 

emphasis from the current capabilities delivered by manned battle 

management platforms, such as the Airborne Early Warning and Control 

System (AWACS) and Joint Surveillance and Target Attack Radar 

System (JSTARS), to an integrated network of sensors providing new and 

upgraded capabilities.

This testimony is based on two reports we issued on the F-35 program in 

April 2019, our past F-35 work, and an oral briefing we provided to 

 1

The international partners are the United Kingdom, Italy, the Netherlands, Turkey, 

Canada, Australia, Denmark, and Norway. These nations contributed funds for system 

development and all but Canada have signed agreements to procure aircraft. In addition, 

Belgium, Israel, Japan, and South Korea have signed on as foreign military sales 

customers. 
Page 2 GAO-19-456T Defense Acquisitions

Congress on ABMS in February 2019.2 This statement (1) assesses the 

F-35 program’s development progress, plans for modernization, and 

sustainment and supply chain efforts; and (2) describes DOD’s current 

planning efforts for ABMS.

To assess the F-35 program’s development and modernization plans, we 

reviewed program development documents as well as modernization 

planning documents that should be completed prior to awarding a 

development contract, according to GAO best practices. We interviewed 

DOD officials and contractor representatives regarding the program’s 

development and modernization efforts. We analyzed monthly contractor 

reliability and maintainability (R&M) reports and compared these to 

program requirements. We reviewed the F-35 R&M Improvement 

Program—the program’s plan to improve R&M metrics’ performance. We 

also interviewed DOD officials and contractor representatives regarding 

the program’s R&M performance. We also summarized our past findings 

on the F-35 program’s supply chain and sustainment efforts.

To describe the Air Force’s ABMS planning efforts, we reviewed and 

analyzed DOD program and planning documents. We also interviewed 

officials from DOD, including the Office of Cost Assessment and Program 

Evaluation, the Office of the Assistant Secretary of the Air Force for 

Acquisition, Technology and Logistics, Air Combat Command, and 

multiple Air Force program offices.

We assessed the reliability of the information we gathered regarding the 

F-35 program and ABMS by reviewing supporting documentation and 

interviewing knowledgeable officials. Based on these steps, we 

determined that all the data we used were sufficiently reliable for the 

purposes of this written statement. We discussed the information in this 

written statement with DOD officials and incorporated their comments as 

appropriate. The work on which this statement is based, has been 

conducted in accordance with generally accepted government auditing 

standards. Those standards require that we plan and perform the audit to 

obtain sufficient, appropriate evidence to provide a reasonable basis for 

our findings and conclusions based on our audit objectives. We believe 

 2

GAO, F-35 Joint Strike Fighter: Action Needed to Improve Reliability and Prepare for 

Modernization Efforts, GAO-19-341 (Washington, D.C.: Apr. 29, 2019); and F-35 Aircraft 

Sustainment: DOD Needs to Address Substantial Supply Chain Challenges, GAO-19-321 

(Washington, D.C. Apr. 25, 2019).
Page 3 GAO-19-456T Defense Acquisitions

that the evidence obtained provides a reasonable basis for our findings 

and conclusions based on our audit objectives.

The F-35 plays a key role in DOD’s modernization efforts. However, it 

faces concerns in several areas that will inform the program’s cost and 

performance in the future. These include the risk in its modernization 

efforts, its aircraft not meeting all reliability targets, and sustainment and 

supply chain challenges. Specifically, the F-35 program plans to award 

Block 4 development contracts before it has key business case 

documents that would normally inform this decision. Also, the program is 

not meeting all of its Reliability and Maintainability (R&M) targets. Finally, 

the F-35 program’s sustainment costs are rising as it also faces 

significant supply chain challenges.

The F-35 baseline aircraft program completed development in April 2018. 

It started formal operational testing of the baseline aircraft in December 

2018 after a 3-month delay. This testing was delayed for two main 

reasons: (1) to resolve critical deficiencies identified in developmental 

testing, and (2) to accommodate an unexpected grounding following the 

crash of an F-35B in September 2018. According to a test official, the 

program expects to complete testing in December 2019, about 3 months 

later than planned due to delays with the simulator that is used for more 

complex testing. Until that testing is complete, there is still a risk that 

additional deficiencies may be identified. With the program wrapping up 

development of the baseline program, it is transitioning to early 

development and testing activities for the Block 4 modernization efforts, 

which the F-35 Joint Program Office estimates will cost about $10.5 

billion. With Block 4, DOD plans to add new capabilities and modernize 

the F-35 aircraft to address evolving threats.

In April 2019, we found that DOD will not have a complete business case 

for Block 4 before it plans to award development contracts in 2019.3

Section 224 of the National Defense Authorization Act for Fiscal Year 

2017 required DOD to submit a report containing certain elements of an 

acquisition program baseline—in essence, a business case—to include 

cost, schedule, and performance information and independent 

estimates—for Block 4. In 2018, we found that DOD’s report to Congress 

 3

GAO-19-341. 

F-35 Modernization, 

Reliability, and 

Sustainment and 

Supply Chain Efforts 

Face Risks and 

Challenges

The F-35 Program Will 

Start Block 4 Development 

without a Full Business 

Case
Page 4 GAO-19-456T Defense Acquisitions

was incomplete.4 In its report, DOD stated that the acquisition program 

baseline would continue to be refined over the next year. DOD officials 

stated that the updated F-35 program baseline, with the Block 4 efforts 

included, will be released in April 2019.

Over the past year, the program has already invested over $1.4 billion, in 

part to gain the knowledge it needs to develop that business case, such 

as a preliminary design review, as well as to establish Block 4 testing 

facilities and support early capabilities’ development. The program 

incorporated some Block 4 activities into its acquisition strategy, which 

was approved in October 2018. However, we found that three key Block 4 

business case documents will not be ready before the program’s planned 

development contract awards in May 2019:

• Independent Technology Readiness Assessment: A Technology 

Readiness Assessment is a systematic, evidence-based process that 

evaluates the maturity of hardware and software technologies critical 

to the performance of a larger system or the fulfillment of the key 

objectives of an acquisition program. The program office plans to 

conduct a partial independent assessment of initial capabilities 

sometime between October and December 2019 with additional 

assessments to follow. A program official stated that technologies will 

not be integrated into the aircraft until they are adequately mature. 

However, without a complete independent Technology Readiness 

Assessment, the program will not have identified potential critical 

technology elements and, as a result, may be at risk of delaying the 

delivery of new capabilities.

• Test and Evaluation Master Plan: Although the F-35 program has 

begun testing Block 4 capabilities, it does not have an approved Test 

and Evaluation Master Plan. The Test and Evaluation Master Plan 

documents the overall structure, strategy, and objectives, as well as 

the associated resources needed for execution. Developmental and 

operational test officials have expressed concerns about the lack of 

an approved test plan, uncertain funding, the number of test aircraft 

available, and the draft test schedule, among other things. An 

approved, properly resourced test plan is essential for planning and 

preparing for adequate testing of the Block 4 capabilities. According to 

these officials, without an approved plan, the F-35 program is 

providing the test authorities with capabilities to be tested without 

 4

GAO, F-35 Joint Strike Fighter: Development Is Nearly Complete, but Deficiencies Found 

in Testing Need to Be Resolved, GAO-18-321 (Washington, D.C.: June 5, 2018).
Page 5 GAO-19-456T Defense Acquisitions

giving them the necessary direction on how to adequately prepare to 

conduct the tests, making it difficult to execute testing. While this is 

still a concern, F-35 program officials explained that over the past 3 

months they have been providing the test authorities with the direction 

needed to conduct testing.

• Independent Cost Estimate: The Block 4 Independent Cost 

Estimate, which details the program’s total estimated life cycle cost, is 

not complete. In August 2017, we reported that DOD estimated the 

development funding needed for the first phase of Block 4 was 

projected to be over $3.9 billion through 2022.5 Since then, the 

program incorporated more fidelity and specific Block 4 efforts that 

were not in the original estimate into its Block 4 cost estimate. Based

on the program office’s latest estimate, the cost of Block 4 capabilities 

is expected to be $10.5 billion through 2024. According to OSD’s Cost 

Assessment and Program Evaluation office, it will provide the 

Independent Cost Estimate between October and December 2019 to 

support the F-35 program’s pending full-rate production decision, but 

this would occur several months after the program plans to award the 

Block 4 development contracts. According to the GAO Cost Guide, an 

Independent Cost Estimate is considered one of the best and most 

reliable estimate validation methods as it provides an independent 

view of expected program costs that tests the program office’s 

estimate for reasonableness.6 Without an Independent Cost Estimate, 

Congress does not have insight into the full potential cost of Block 4.

The expected completion dates for these documents are between 

October and December 2019, at the earliest. Figure 1 shows key Block 4 

dates such as the Block 4 re-plan, which included revising the cost 

estimate for Block 4 that DOD established in 2017, the planned 

development contract awards, and planned completion dates for the three 

remaining critical business case documents.

 5

GAO, F-35 Joint Strike Fighter: DOD’s Proposed Follow-on Modernization Acquisition 

Strategy Reflects an Incremental Approach Although Plans Are Not Yet Finalized, 

GAO-17-690R (Washington, D.C.: Aug. 8, 2017).

6

GAO, GAO Cost Estimating and Assessment Guide: Best Practices for Developing and 

Managing Capital Program Costs, GAO-09-3SP (Washington, D.C.: Mar. 2, 2009).
Page 6 GAO-19-456T Defense Acquisitions

Figure 1: Three Business Case Documents Will Not Be Ready Before the Planned 

Development Contract Awards

As seen in figure 1, the program office plans to award Block 4 

development contracts in May 2019, at least five months before any of 

the critical business case documents will be available. Based on best 

practices identified by GAO, without an independent Technology 

Readiness Assessment, Test and Evaluation Master Plan, or an 

Independent Cost Estimate, program officials cannot have a high level of 

confidence that the requirements are firm and that risk has been 

adequately reduced before beginning efforts estimated to cost $10.5 

billion in funding to develop Block 4.7 If program officials move ahead with 

Block 4 contracts without gaining the knowledge that a full business case 

would provide, Block 4 modernization efforts will be at risk of experiencing 

the same kind of cost and schedule growth the baseline development 

program experienced.

To address this risk, in April 2019, we recommended to the DOD that it 

should ensure the F-35 program office complete its business case, to 

include the three documents discussed above, at least for the initial Block 

4 capabilities under development before initiating additional development 

 7

GAO, Weapon Systems Annual Assessment: Knowledge Gaps Pose Risks to Sustaining 

Recent Positive Trends, GAO-18-360SP (Washington, D.C.: Apr. 25, 2018).
Page 7 GAO-19-456T Defense Acquisitions

work.8 DOD did not concur with this recommendation. In its comments, 

DOD stated that the F-35 program office has adequate knowledge to 

begin Block 4 development. We maintain, however, that completing its 

business case before awarding its Block 4 development contracts would 

put DOD and the program in a better position to effectively and 

successfully develop Block 4 capabilities.

As we reported in April 2019, the program has made slow, consistent 

progress in improving the F-35’s R&M metrics’ performance but half of 

the metrics are not achieving targets.9 All F-35 variants are generally 

performing near or above targets for four of the eight R&M metrics, while 

still falling short for the other four. Each F-35 aircraft variant is measured 

against eight R&M metrics, four of which are in part of the contract. All 

eight R&M metrics are described in the program’s Operational 

Requirements Document (ORD)—the document that outlines the targeted 

performance levels for these metrics that DOD and the military services 

agreed the F-35 should meet in 2000. Based on our analysis, while the 

program is on track to meet half of the targets, the program office has not 

taken adequate steps to ensure the others will be met. Additionally, in 

December 2018, the Director, Operational Test & Evaluation reported 

that, although performance for the four under-performing metrics has 

shown slow growth over the years, none of these metrics are meeting 

interim goals needed to reach requirements at each variant’s maturity.10

Each F-35 variants’ R&M performance against these metrics is shown in 

table 1.

 8

GAO-19-341. 

9

GAO-19-341. 

10Director, Operational Test & Evaluation, Fiscal Year 2018 Annual Report (December 

2019). The F-35 aircraft reach maturity when all variants have flown a combined 200,000 

hours, with each variant flying at least 50,000 hours. The F-35A reached its planned 

maturity in July 2018, but is still not near meeting four of its eight metrics. The F-35B and 

C variants have more time to meet their metrics before they reach their planned maturity 

in 2021 and 2024 respectively.

The F-35 Program Is Still 

Not Meeting All Reliability 

and Maintainability Targets
Page 8 GAO-19-456T Defense Acquisitions

Table 1: The F-35 Reliability & Maintainability Metrics’ Performance as of August 2018

Metrica Contractually required F-35A F-35B F-35C

Mission Reliabilityb—measures the probability of successfully completing 

a mission of average duration ✔ ● ● —

Mean flight hours between failure (design controlled)—measures time 

between failures that are directly attributable to the design of the aircraft 

and are considered fixable with design changes

✔ ● ● ●

Mean time to repair—measures the amount of time it takes a maintainer 

to repair a failed component or device ✔ ◓ ◓ ◓

Maintenance man hours per flight hour—measures the average amount 

of time spent on scheduled and unscheduled maintenance per flight hour ✔ ● ◓ ●

Mean flight hours between maintenance events—also referred to as 

the logistics reliability metric, measures time between maintenance, 

unscheduled inspections, and servicing actions, including consumablesc — ○ ○ ◓

Mean flight hours between removals—measures the time between part 

removals from the aircraft for replacement from the supply chain — ○ ○ ○

Mean flight hours between critical failure—measures the time between 

failures that result in the loss of a capability to perform a mission-critical 

capability

— ○ ○ ○

Mean corrective maintenance time for critical failure—measures the 

amount of time it takes to correct critical failure events — ○ ○ ○

Legend:

●: Metric is at or above current targets

◓: Metric is at or above minimum targets

○: Metric is below minimum targets

✔: Metric is contractually required

—: not available

Source: GAO analysis of contractor data. | GAO-19-456T

a

Each metric is measured using a 3-month average and reported on a monthly basis; this table 

summarizes the Joint Reliability and Maintainability Evaluation Team’s review of reliability growth and 

maintainability improvement data from November 2009 through August 2018.

b

Mission Reliability is a key performance parameter. Mission reliability, as well as performance 

against the targets related to all of these metrics, will be evaluated during initial operational test and 

evaluation.

c

Consumable parts are nonrepairable items or repair parts that can be discarded more economically 

than they can be repaired or that are consumed in use (such as oil filters, screws, nuts, and bolts).

Since the program began tracking R&M performance in 2009, it has seen 

small, annual improvements. Over the past year, all variants showed a 

slight improvement in targeted performance levels for one metric, the 

mean flight hours between failure—design controlled, but saw little or no 

discernable improvement for the four metrics not meeting targets. 

However, based on current performance, the program does not expect to 

meet those targets by full aircraft maturity. According to F-35 program 
Page 9 GAO-19-456T Defense Acquisitions

officials, the ORD R&M metrics should be re-evaluated to determine more 

realistic R&M performance metrics, but the program has not yet taken 

actions to do so. Until the program office does so, it remains accountable 

for ensuring those ORD R&M metrics are achieved.

In June 2018, we recommended that the F-35 program identify steps it 

needs to take to ensure the F-35 aircraft meet R&M requirements before 

each variant reaches maturity and update its R&M Improvement Program 

(RMIP)—DOD’s action plan for improving R&M—with these steps.11 DOD 

concurred with our recommendation but has yet to take substantive 

actions to address it. DOD did, however, complete 16 improvement 

projects since we last reported on this. Despite completing these projects, 

there were not significant gains in the R&M metrics not meeting targets. 

Program officials advised, however, that measurable improvements in 

R&M can take time to manifest. To speed this process, the program is 

accelerating planned upgrades to older aircraft where appropriate, which 

officials stated should translate to an overall improvement in the 

program’s R&M performance.

The F-35 program office has estimated that implementing all of the 

identified improvement projects currently contained in its RMIP could 

result in potential life cycle cost savings of over $9.2 billion by improving 

the F-35’s R&M. However, we found that, as of December 2018, the 

guidance the F-35 program office has used to implement the RMIP does 

not define specific, measurable objectives for what the desired goals for 

the F-35’s R&M performance should be or align improvement projects 

with R&M goals.12 Furthermore, the RMIP has not been a funding priority.

 11GAO-18-321. The F-35 program began tracking its R&M metrics in 2009 and 

documented the RMIP’s approach in April 2014. In June 2018, we found that the F-35 

program did not have a plan to ensure that all R&M targets would be met by each variant’s 

aircraft maturity.

12GAO-19-341. 

The F-35 Program Office’s 

Improvement Plan Does 

Not Address UnderPerforming Targets
Page 10 GAO-19-456T Defense Acquisitions

Federal internal control standards state that programs should define 

objectives when implementing programs such as the RMIP.13 Although 

the F-35 program RMIP’s guidance has a general goal of improving R&M, 

it does not identify achieving the eight R&M targets listed in the ORD as 

an objective. Program officials acknowledged that the RMIP’s guidance 

does not include such an objective. Instead, officials stated they are using 

the RMIP to prioritize and fund projects that will improve aircraft 

availability and mission capability—neither of which are included in the 

eight R&M metrics, but are necessary and important initiatives.14 The 

program is focusing on these two areas in part because a September 

2018 memorandum from the Secretary of Defense to the Secretaries of 

the military departments included a goal for the F-35 fleet to attain a 

mission capable rate of 80 percent by the end of fiscal year 2019. 

According to program officials, improving these two areas will translate 

into improvements in the F-35 overall R&M. However, we found that the 

RMIP’s guidance does not discuss these priorities or align how any 

improvement projects would ensure targets under all eight R&M targets 

will be met.15

In our prior work on weapon system acquisitions, we have identified a 

number of best practices for improving program outcomes if implemented, 

such as clearly establishing well-defined requirements and securing 

stable funding that matches resources to requirements.16 We found that 

the program office has not prioritized or dedicated funding in its budget to 

 13GAO’s Standards for Internal Control in the Federal Government require agencies to 

define measurable objectives when implementing programs. Agencies should also 

consider requirements when defining these objectives. Objectives should be defined in 

measurable terms so that performance toward achieving those objectives can be 

assessed. Measurable objectives are generally free of bias and do not require subjective 

judgments to dominate their measurement. Measurable objectives are also stated in a 

quantitative or qualitative form that permits reasonably consistent measurement. GAO, 

Standards for Internal Control in the Federal Government, GAO-14-704G (Washington, 

D.C.: September 2014). 

14Aircraft availability (also known as air vehicle availability) and mission capability both 

measure the percentage of time during which aircraft are safe to fly, available for use, and 

able to perform at least one tasked mission. The air vehicle availability metric assesses all 

aircraft in the fleet, including those in the possession of the F-35 units and those at the 

depots for modifications. The mission capability metric assesses only aircraft that are in 

the possession of F-35 units.

15GAO-19-341. 

16GAO, Best Practices: Better Matching of Needs and Resources Will Lead to Better 

Weapon System Outcomes, GAO-01-288 (Washington, D.C.: Mar. 8, 2001).
Page 11 GAO-19-456T Defense Acquisitions

improve R&M, in part because program officials explained that they were 

focused on initiatives intended to lower the cost of the aircraft.17 In 

addition, any current funding for R&M improvement projects comes from 

the program’s operation and maintenance funds, which are only available 

for one fiscal year. Officials explained that, if the funding runs out or is 

used by the program for other efforts, then R&M projects will go unfunded 

or be suspended until new funding is available. In fiscal year 2018, for 

example, while some projects were completed, several other projects 

were suspended when that year’s funding ran out. As of December 2018, 

according to a contractor representative, all of the identified improvement 

projects currently unfunded in the program’s RMIP would cost about $30 

million to implement, but were not funded.

Program officials also stated that they are in the process of revising the 

RMIP and have considered including more specific objectives in addition 

to improving aircraft availability and mission capability, such as more

focus on improving R&M performance where ORD R&M targets are not 

currently being met. According to the program, any revisions to the RMIP 

and changes to how it will be funded, however, will not be complete until 

April 2019.

By not defining objectives in its RMIP guidance for meeting all eight R&M 

metrics, aligning which improvement projects will ensure those metrics 

are met, and prioritizing funding for those projects, the program is at risk 

of not fully meeting its R&M targets. As a result, the warfighter may 

accept aircraft that are less reliable than originally planned, and whose 

operation and sustainment costs may raise affordability questions. In 

addition, the military services recently identified the need to cut 

sustainment costs—by 43 percent in the case of the Air Force—to 

improve the F-35’s affordability in sustainment. Increasing costs from less 

reliable aircraft will add strain to an already unaffordable program.

To address these issues, in April 2019, we recommended to DOD that it 

should ensure that the F-35 program office

1. assess whether the ORD R&M targets are still feasible and revise the 

ORD accordingly;

2. as it revises its RMIP, identify specific and measurable R&M 

objectives in its RMIP guidance;

 17GAO-19-341.
Page 12 GAO-19-456T Defense Acquisitions

3. as it revises its RMIP, identify and document which RMIP projects will 

achieve the identified objectives of the RMIP guidance; and

4. prioritize funding for the RMIP.18

DOD concurred with these recommendations and stated that it will take 

actions to address them.

We have previously reported on the F-35 program’s rising estimated 

sustainment costs and challenges maintaining an expanding fleet. In 

October 2017, we reported that estimated F-35 life-cycle sustainment 

costs increased by 24 percent from fiscal years 2012 through 2016 due to 

an increase in projected flying hours and other factors.19 We also reported 

that sustainment costs were not fully transparent to the military services. 

For example, the Marine Corps received an initial funding requirement for 

fiscal year 2017 sustainment of $293 million, which then increased to 

$364 million in the execution without a full explanation from the program 

office. We recommended that DOD take steps to improve communication 

with the services and provide more information about how F-35 

sustainment costs they are being charged relate to the capabilities 

received. DOD concurred with the recommendation and has begun taking 

actions to address it.20

In addition, DOD faces substantial supply chain challenges that are 

lowering F-35 aircraft performance. In April 2019, we reported that F-35 

aircraft performance was falling short of warfighter requirements—that is, 

aircraft could not perform as many missions or fly as often as required.21

Specifically, F-35A aircraft were mission capable only 52 percent of the 

time from May through November 2018—far short of the 80 percent target 

set by the former Secretary of Defense. This lower-than-desired aircraft 

performance is due largely to F-35 spare parts shortages and limited part 

 18GAO-19-341. 

19GAO, F-35 Aircraft Sustainment: DOD Needs to Address Challenges Affecting 

Readiness and Cost Transparency, GAO-18-75 (Washington, D.C.: Oct. 26, 2017).

20In December 2018, DOD provided a report to Congress that discusses the steps that 

DOD is taking to provide increased transparency of F-35 sustainment costs to the U.S. 

services. Office of the Secretary of Defense, Report to Congress on F-35 Joint Strike 

Fighter Sustainment Affordability and Transparency (December 2018).

21GAO-19-321.

Continued Concerns with 

F-35 Sustainment Costs 

and Supply Chain, and 

Logistics System
Page 13 GAO-19-456T Defense Acquisitions

repair capabilities. For example, during this time period, F-35 aircraft were 

unable to fly about 30 percent of the time due to spare parts shortages.

Additionally, DOD’s capabilities to repair F-35 spare parts at its depots 

are years behind schedule, which has resulted in an average of 188 days 

to repair an F-35 part and a backlog of about 4,300 spare parts awaiting 

repair at military depots or manufacturers. We also reported that DOD 

faces challenges managing, moving and maintaining accountability of F35 parts within the supply chain. We made eight recommendations to 

DOD, including that DOD determine what actions are needed to close the 

gap between warfighter requirements for aircraft performance and F-35 

supply chain capabilities. DOD concurred with the recommendations and 

identified actions that it was taking or planned in response.

Finally, the F-35’s Autonomic Logistics Information System (ALIS) has the 

potential to lead to increased costs for the program if key issues are not

addressed. ALIS is the F-35’s central logistics system intended to support 

operations, mission planning, supply-chain management, maintenance, 

and other processes. In April 2016, we identified several risks, including 

that ALIS (1) was not initially designed to be deployable, (2) lacked 

redundant infrastructure, (3) did not communicate well with legacy aircraft 

systems, (4) had data accuracy and accessibility issues, and (5) had 

security risks.22 In addition, DOD had not included certain analyses and 

information, such as historical cost data, to increase the credibility and 

accuracy of ALIS’s estimated costs. Further, a 2013 DOD-commissioned 

study found that schedule slippage and functionality problems with ALIS 

could lead to between $20 billion and $100 billion in additional costs.

We have made several recommendations to DOD to improve ALIS 

planning and cost estimates, and to develop a performance measurement 

process for ALIS to better address problems based on actual system 

performance and user requirements.23 DOD generally concurred with our 

recommendations and has taken some actions, including developing a 

plan that identifies and prioritizes key ALIS risks. However, more work 

remains. We are currently conducting a review examining DOD’s 

progress in implementing our ALIS-related recommendations, addressing 

 22GAO, F-35 Sustainment: DOD Needs a Plan to Address Risks Related to Its Central 

Logistics System, GAO-16-439 (Washington, D.C.: Apr. 14, 2016).

23See GAO-16-439 and GAO, F-35 Sustainment: Need for an Affordable Strategy, 

Greater Attention to Risks, and Improved Costs Estimates, GAO-14-778 (Washington, 

D.C.: Sept. 23, 2014).
Page 14 GAO-19-456T Defense Acquisitions

concerns from ALIS users, identifying emergent financial and operational 

risks associated with ALIS, taking near-term actions to improve ALIS 

functionality, and assessing DOD’s actions regarding the long-term 

viability of ALIS to ensure capable sustainment of the F-35 fleet. We plan 

to issue a report based on our current work later in 2019.

Based on our ongoing work, ABMS is early in the acquisition process, as 

the specific capabilities and overarching acquisition strategy are still to be 

determined by the Air Force. As a result, the Air Force has not yet 

established a cost and technical baseline for ABMS. When ABMS 

planning began in 2017, program officials stated that the intent of the 

program was to replace and modernize the capabilities of the AWACS 

system—which provides the warfighter with the capability to detect, 

identify, and track airborne and maritime threats. But changes in Air Force 

expectations for how it would fight during future conflicts led the 

department to assess options for developing a more robust and 

survivable air, land, and sea battle management system that can operate 

in contested environments. In July 2018, the ABMS Initial Capabilities 

Document—which describes capability needs and associated gaps—was 

approved by the DOD Joint Requirements Oversight Council.

Our ongoing work also found that, in December 2018, the Air Force 

determined it would not continue its planned JSTARS Recapitalization 

program—which was intended to provide surveillance and information on 

moving ground targets—well into the future, as initially expected. As a 

result of a recent study, the Air Force has extended the estimated service 

life of the JSTARS fleet, and will incorporate its capabilities into the ABMS 

in the short term, and retire JSTARS in the 2030s.

Our preliminary observations indicate that the details about ABMS are still 

to be determined. The Air Force expects to fully define ABMS through an 

Analysis of Alternatives (AOA) that it plans to complete by the summer of 

2019, as shown in figure 2.24

 24An Analysis of Alternatives is an analytical comparison of the operational effectiveness, 

suitability, risk, and life-cycle cost of alternatives under consideration to satisfy validated 

capability needs that are typically identified in an Initial Capabilities Document.

Air Force’s Advanced 

Battle Management 

System Acquisition 

Strategy Is in the 

Early Planning 

Stages
Page 15 GAO-19-456T Defense Acquisitions

Figure 2: Preliminary Observations on Key Planning and Development Events for 

the Advanced Battle Management System (ABMS)

The ABMS AOA, led by the Air Force’s Air Combat Command, will assess 

how ABMS will deliver air-centric capabilities, such as those currently 

provided by AWACS. Air Force officials explained that they plan to utilize 

an existing AOA completed for the JSTARS Recapitalization program, 

approved in May 2012, to identify and assess ABMS’s potential ground 

target tracking capabilities. Originally planned as a 9-month study, Air 

Force officials stated that the ABMS AOA was shortened to a 6-month 

effort. As a result, the Air Force received conditional approval to reduce 

the number of alternatives studied from five to three.

Our ongoing work indicates that the Air Force plans to develop ABMS 

over three phases. The first phase began in fiscal year 2018 and goes 

through 2023. In this phase, the Air Force plans to integrate existing 

sensors, improve battle management systems, and upgrade 

communication networks across 10 existing acquisition programs. Table 2 

includes information on three existing programs the Air Force plans to 

enhance during the first phase of ABMS.
Page 16 GAO-19-456T Defense Acquisitions

Table 2: Preliminary Observations on the Advanced Battle Management System Existing Programs’ Missions and Planned 

Enhancements for the First Development Phase

Airborne Early Warning and 

Control System (AWACS)

Joint Surveillance and Target 

Attack Radar System (JSTARS)

Control and Reporting Center 

(CRC)

Mission Provides air operations battle 

management, and air surveillance 

and identification

Provides ground surveillance to 

support attack operations and 

targeting

Provides battle management 

functions of joint operations, using 

data fused from various sources and 

sensors

Planned 

enhancements

Purchase seven legacy aircraft to 

modernize to current configuration

Upgrade to Link 16 system to allow 

communication and data transfer to 

next generation fighter aircrafta

Provide access to multiple levels of 

security data on aircraft

Upgrade Common Data Link 

communication systemb Add ground moving target warning capability

Upgrade to Link 16 systema

Source: GAO analysis of Department of Defense documentation. | GAO-19-456T

a

Link 16 is an anti-jam, high-speed, secure, data and voice communications standard.

b

Common Data Link is a digital communications technology which provides a data link between 

aerial/space platforms and common ground stations.

According to an Air Force acquisition official, the technologies associated 

with the first phase are considered to be mature but there may be risks as 

the Air Force integrates technologies.

Air Force officials explained that their approaches to the second and third 

phases of ABMS are not fully developed, but noted that the phases would 

be informed by the AOA results. That said, the Air Force expects to start 

phase 2 in 2024 by integrating advanced sensors and software into its 

existing battle management command and control platforms while at the 

same time retiring JSTARS. Air Force officials have reported that the third 

phase, planned for the mid-2030s, is expected to provide multi-sensor, 

resilient battle management command and control capability using 

multiple types of communications methods, with an initial operational 

capability planned for 2035. The Air Force estimates that ABMS’s 

acquisition cost through fiscal year 2024 will be $3.8 billion.

Because ABMS is composed of many different defense acquisition 

programs, the Air Force intends to manage it as a family of systems 

directed by a Chief Architect and not a traditional acquisition program 

manager. According to the Air Force, the ABMS Chief Architect is the first 

of its kind, and the Air Force believes the position will be instrumental in 

integrating the various programs and technologies into an overall system. 

Based on our preliminary analysis, the roles and responsibilities of the 
Page 17 GAO-19-456T Defense Acquisitions

Chief Architect have not been fully defined. However, according to the Air 

Force, the Chief Architect is expected to be responsible for (1) leading a 

high-level analysis and determining the overall design of ABMS, (2) 

coordinating with the service-level commands and the acquisition 

programs involved to make sure they are aligned with the ABMS 

development, and (3) identifying the enabling technologies for integration 

into ABMS.

Chairman Norcross, Ranking Member Hartzler, and members of the 

Subcommittee, this completes my prepared statement. I would be 

pleased to respond to any questions you may have. We look forward to 

continuing to work with the Congress as we to continue to monitor and 

report on the progress of the F-35 program and the ABMS.

If you or your staff have any questions about this testimony, please 

contact Michael J. Sullivan at (202) 512-4841 or sullivanm@gao.gov. 

Contact points for our Office of Congressional Relations and Public 

Affairs may be found on the last page of this statement. Individuals 

making key contributions to this statement are Justin Jaynes (Assistant 

Director), Diana Maurer, Jennifer Baker, Desirée E. Cunningham, Alissa 

Czyz, Stephanie Gustafson, Kasea Hamar, Jeff Hubbard, Jessica Karnis, 

Matt Metz, Robin Wilson, and Lauren Wright.

GAO Contact and 

Staff 

Acknowledgments

(103404)
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