F-35 Joint Strike Fighter:
Actions Needed to Address Manufacturing and Modernization Risks
GAO-20-339: Published: May 12, 2020. Publicly Released: May 12, 2020.
Multimedia:
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PODCAST: F-35 Annual Program Review
Jon Ludwigson joins the Watchdog Report to discuss issues with the F-35 Joint Strike Fighter program.
Additional Materials:
- Highlights Page:
- Full Report:
- Accessible Version:
Contact:
(202) 512-4841
ludwigsonj@gao.gov
Office of Public Affairs
(202) 512-4800
youngc1@gao.gov
The F-35 program produced more aircraft and negotiated lower prices in 2019. However, the program is not meeting standards aimed at ensuring consistent, high-quality products, and fielded aircraft do not meet reliability goals.
Also, the cost to modernize aircraft systems went up about $1.5 billion (14%) since the program’s May 2019 annual report to Congress. Due to development delays, this reporting requirement will expire before the effort is complete. We suggest Congress consider extending it.
We made 5 recommendations, including some to help the Defense Department make its modernization cost estimate more comprehensive and credible.
An F-35B Exercising Its Short Takeoff and Vertical Landing Capability on the USS America

Fighter jet
Multimedia:
-
PODCAST: F-35 Annual Program Review
Jon Ludwigson joins the Watchdog Report to discuss issues with the F-35 Joint Strike Fighter program.
Additional Materials:
- Highlights Page:
- Full Report:
- Accessible Version:
Contact:
(202) 512-4841
ludwigsonj@gao.gov
Office of Public Affairs
(202) 512-4800
youngc1@gao.gov
What GAO Found
The F-35 program is at risk of missing its test schedule and not meeting manufacturing leading practices. In 2019, the F-35 program conducted much of its planned operational testing but extended the schedule by 9 months, which delays the program's full-rate production decision to between September 2020 and March 2021. Over that time, the program will continue to deliver aircraft.
In addition, while the F-35 program has increased the production rate and negotiated lower aircraft prices, it is not meeting manufacturing leading practices identified by GAO. Specifically, only about 3,000 of the over 10,000 airframe contractor's manufacturing key processes meet predefined design standards for ensuring product quality. Also, the fielded aircraft, over 500 so far, do not meet the program's reliability and maintainability goals. Although the contractor is changing manufacturing processes to address problems and improve efficiency, more remains to be done. Unless the program office evaluates the risks of not meeting these leading practices, the military services and international partners are at risk of not receiving the quality aircraft they purchased.
An F-35 in Flight over Edwards Air Force Base

In addition, the July 2019 suspension of Turkey from the F-35 program—due to security concerns after its acquisition of Russian defense equipment—is likely to compound production risks. The program has identified new sources for 1,005 parts produced by Turkish suppliers, but the program is assessing the effect of 15 key parts not currently being produced at the needed production rate.
In 2019, estimated development costs to modernize the F-35's hardware and software systems—known as Block 4—increased by over $1.5 billion. The cost increase puts estimated Block 4 development costs at $12.1 billion. However, the cost estimate did not fully adhere to leading practices, such as including all life cycle costs. In addition, while development will continue through 2026, reports on Block 4 that the program submits to Congress are slated to end in 2023. Without continued Block 4 reporting through the development phase, Congress will lack important oversight information.
Why GAO Did This Study
The acquisition cost for the F-35 program increased substantially in 2019, partially due to the program's addition of estimated costs for modernization of hardware and software systems, referred to as its Block 4 efforts.
This is the fifth report under the provision that Congress included in statute for GAO to review the F-35 program annually until the program reaches full-rate production. This is also the first report under another provision in statute to review the program's production and Block 4 progress annually through 2024. Among other objectives, this report assesses (1) the program's production performance and (2) the program's modernization cost estimate and development progress. GAO reviewed Department of Defense (DOD) and contractor documentation and interviewed DOD officials and contractor representatives.
What GAO Recommends
Congress should consider extending DOD's reporting requirement for Block 4 modernization beyond 2023. GAO is also making five recommendations to DOD. While DOD did not concur with two of these recommendations—including to evaluate production risks and update its Block 4 cost estimate with a program-level plan, it identified actions that, if implemented, will meet the intent of these recommendations. DOD concurred with GAO's three other recommendations.
For more information, contact Jon Ludwigson at (202) 512-4841 or ludwigsonj@gao.gov.
Matter for Congressional Consideration
Status: Open

Comments: Congress has not extended the Block 4 reporting requirement in Section 224(d) of the National Defense Authorization Act for Fiscal Year 2017. We will continue to monitor any action the Congress may take in this regard.
Matter: Congress should consider revising Section 224(d) of the National Defense Authorization Act for Fiscal Year 2017, Pub. L. No. 114-328, to extend DOD's Block 4 reporting requirement until all Block 4 capabilities are fielded to ensure that Congress is aware of cost and schedule growth beyond 2023. (Matter for Consideration 1)
Recommendations for Executive Action
Status: Open

Comments: DOD did not concur with this recommendation, citing updates the F-35 program office provides to oversight entities within DOD. We maintain that the program office should provide these same updates to Congress as well. Without a substantive assessment highlighting specific production risks, as well as the steps DOD will take to mitigate them, Congress may not have key insights into the risks that remain with the program and to the overall effort to deliver F-35s to the warfighter. DOD has agreed to keep the Congress apprised of these matters in its quarterly briefings to the defense committees.
Recommendation: The OUSD (A&S) should direct the F-35 program office to provide information that is similar to that which is statutorily required after the milestone C review to Congress ahead of the milestone C review (full-rate production decision). This submission should include an evaluation of the production risks associated with critical production processes that are not in control, reliability and maintainability (R&M) targets that are not met, and supplier readinessparticularly for those replacing Turkish suppliers, along with the steps it is taking to address those risks. (Recommendation 1)
Agency Affected: Department of Defense
Status: Open

Comments: DOD concurred with this recommendation. In response to our report, DOD stated that future reports to Congress will include prior and future costs, outside of the Future Years Defense Program costs. As of September 15, 2020, DOD has not yet issued an updated report to Congress. We will monitor DOD's efforts to address this recommendation once it releases its next report.
Recommendation: The OUSD (A&S) should direct the F-35 program office to establish a Block 4 cost estimate baseline that includes all Block 4 costs, including incurred costs and future costs in its reports to Congress as required by the NDAA for Fiscal Year 2017, so that Congress has a complete understanding of all Block 4 costs and can compare this baseline to future cost estimates and performance. (Recommendation 2)
Agency Affected: Department of Defense
Status: Open

Comments: Though DOD did not concur with this recommendation, in response to this report, DOD agreed to evaluate moving to a program-level, product-oriented work breakdown structure in 2021. We will continue to monitor DOD's efforts to address this recommendation.
Recommendation: The OUSD (A&S) should direct the F-35 program office to complete a program office level, product-oriented work breakdown structure for the next update to its Block 4 cost estimate to ensure that the estimate meets the comprehensive leading practices. (Recommendation 3)
Agency Affected: Department of Defense
Status: Open

Comments: DOD concurred with this recommendation. In response to this report, DOD stated that the F-35 program office estimate is aligned with the DOD's Cost Assessment and Program Evaluation's approach and methodology for performing development cost estimates. However, DOD did not identify specific actions it plans to take to include risk and uncertainty into its next Block 4 cost estimate update. We will continue to monitor any actions DOD takes in this regard.
Recommendation: The OUSD (A&S) should direct the F-35 program office to conduct risk and uncertainty analyses for the next update to its Block 4 cost estimate to ensure that the estimate meets the credible leading practices. (Recommendation 4)
Agency Affected: Department of Defense
Status: Open

Comments: DOD concurred with this recommendation. In response to this report, DOD stated that it continues to evaluate technology readiness levels for Block 4. It noted that Office of the Under Secretary of Defense for Research and Engineering would conduct and independent technology readiness assessment of the Block 4 effort, which the program would use to inform future cost estimates. In May 2020, the F-35 Program Office issued a Technology Readiness Assessment Plan for Block 4. This plan outlines an incremental assessment approach aligned with Block 4 capability drops beginning with the drop scheduled for April 2021. We will continue to monitor DOD's efforts to address this recommendation.
Recommendation: The OUSD (A&S) should direct the F-35 program office to consider the results of its future technology readiness assessment of all Block 4 technologies and incorporate the cost and schedule risks of developing those technologies in the next update to its Block 4 cost estimate to ensure that the estimate meets the comprehensive leading practices. (Recommendation 5)
Agency Affected: Department of Defense
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