F-35 Missing Parts: GAO Faults Records on $31B Spares Pool

The U.S. Department of Defense remains unable to reliably account for the global pool of spare parts that sustains the F-35 Lightning II fleet, with the Government Accountability Office having concluded in a report released on November 9 that records covering approximately 26 million parts valued at around $31 billion are inaccurate, incomplete and fail to reflect changes in real time. The parts are held at more than 700 facilities run by contractors and the government, and serve the U.S. Air Force, Navy and Marine Corps alongside the program’s foreign partners and export customers. The Department of Defense has concurred with all four of the auditors’ recommendations, which centre on tracking lost parts and on the officials who manage government property. The findings highlight how far the world’s largest fighter program remains from basic asset accountability more than a decade after the F-35 entered service, with weaknesses that auditors flagged in 2022 and 2023 having remained largely unresolved.

The report found that the F-35 Joint Program Office had still not fully developed procedures to validate the data entering its accountable property system of record, the Enterprise Logistics Management System, which cannot connect directly to the property systems of prime contractor Lockheed Martin and engine maker Pratt & Whitney. Contractor data for the shared spare parts pool arrives only quarterly, which means that some records can be more than three months out of date by the time officials read them. Physical inventories, on which the office has spent at least $17 million since fiscal year 2020, did not adequately verify that the parts existed or that the records were complete. Most significantly, as of March 2026 the office did not know the status of lost parts valued at more than $85 million which the auditors had reported in 2023, when they found that over one million spare parts had gone missing in roughly five years.

The auditors warned that the office had no effective procedures for reviewing losses reported at government managed facilities, which considerably limits its ability to detect fraud, waste or theft, while the unreliable records have also kept the parts off the department’s financial statements, a gap it has begun to address by drafting procedures to value parts that lack cost information. The findings come as the cost of keeping each jet flying remains one of the most closely scrutinised aspects of the program, and as the pool is expected to grow considerably under the 850-jet framework negotiated with Lockheed Martin for Lots 21 to 30. The U.S. Air Force alone has told Congress that F-35s should make up 40 percent of its fighters by 2035.

A Joint Program Office spokesperson stated that the office was developing program specific procedures and training for its accountable property officers, and was building direct, real time data interfaces between government and prime contractor systems. Concerns over the security of the F-35 supply chain had already been raised in September, when Australian Defence Minister Richard Marles confirmed that Australia was investigating with the United States and Lockheed Martin how a consignment of F-35 components shipped from Australia had been diverted to Hong Kong, although he stated that his understanding was that no sensitive parts were involved. The recommendation on validating contractor data that the auditors first issued in 2022 remains open.