GAO: Pentagon Can’t Account for 17,000 Missing F-35 Parts
More than 17,000 F-35 spare parts were missing from the program’s inventory system as of March 2026, with an estimated value of $1.3 billion, according to a new Government Accountability Office report covered by Breaking Defense on November 9. Officials told GAO that figure could climb to $2.5 billion once missing cost data and other acquisition expenses are factored in.
At the root of the problem is a basic systems failure: the F-35 Joint Program Office’s ELMS inventory system cannot interface with the separate property-management systems run by prime contractor Lockheed Martin and engine maker Pratt & Whitney. GAO first flagged this gap in 2022, and as of August 2026 it still had not been fixed.
The JPO relies on contractors to submit inventory data only quarterly, meaning some records can be more than three months out of date by the time they are reviewed. A December 2025 data submission had serial numbers for just 29% of parts records and National Stock Numbers for only 43%. GAO also flagged records listing parts valued at a penny or less as likely data errors rather than real transactions.
The scale of the supply chain makes the tracking problem harder to fix. The program draws on more than 1,900 domestic and 2,100 global suppliers, moving roughly 26 million parts through more than 700 contractor and government facilities. The JPO has spent at least $17 million on physical inventories since fiscal 2020, but GAO found the most recent count did not fully verify that parts were physically present or that records captured all of them.
The findings update a known prior case: a separate 2023 GAO review found one prime contractor had lost more than 1 million parts worth over $85 million between May 2018 and October 2022. As of March 2026, that contractor had filed roughly $28 million in loss reports covering 2012-2025, but the Defense Contract Audit Agency determined it should be liable for only about $6 million. The JPO told GAO it could not confirm whether those reports covered the losses identified in the earlier review, because it had kept no record of the open cases.
GAO warned the accountability gaps could complicate the Pentagon’s $13.7 billion Global Support Solution Reset, a sustainment strategy that includes buying additional spare parts. Without accurate data in its property system of record, the report said, the Defense Department “will lack the information it needs” for both warfighter readiness and reliable financial reporting.
A JPO spokesperson said the office is “actively working” on the issues through new procedures and training and is modernizing its property-management infrastructure. Lockheed Martin said it is working with the JPO and others to improve parts availability, repair turnaround and supply chain performance, and noted a proposed multiyear procurement and sustainment framework — subject to congressional approval — would give suppliers more predictability.
GAO made four recommendations, all of which the Pentagon accepted: tighter oversight of reported losses, and clearer procedures, training and accountability for staff who track government-owned property. The Defense Contract Audit Agency and the JPO are now working on a full F-35 parts inventory, targeted for completion in March 2027.
The findings matter beyond the US Air Force. The F-35 is the only fifth-generation fighter still in full-rate production and is meant to equip thousands of aircraft across NATO and partner air forces. An inventory system that cannot confirm whether a part physically exists directly complicates maintenance planning and the readiness rates allied fleets depend on.
Sources:
Breaking Defense, “Pentagon can’t track thousands of F-35 parts, GAO finds,” Mikayla Easley, November 9, 2026, link — primary source. GAO Report GAO-27-108713, gao.gov — used to verify the underlying findings.
