Pentagon can’t track millions of F-35 spare parts, watchdog finds

The Pentagon is still struggling to track millions of F-35 spare parts worth billions of dollars years after government watchdogs first exposed problems with its tracking system, a new report states.

The Government Accountability Office said Monday that while the DoD’s F-35 program “is the costliest in its history,” the department “struggles to account” for its parts.

The government watchdog described the DoD’s records for F-35 parts as “outdated, inaccurate, and incomplete” and said “DoD has made minimal progress in attaining and maintaining accountability for F-35 parts” since issues were first brought to light seven years ago.

The report follows several audits since 2019 by the GAO and the Department of Defense Inspector General, which revealed numerous problems.

Unlike most aircraft, the F-35 program largely relies on a joint pool of spares – such as engines and tires – for the U.S. Air Force, Navy and Marine Corps, as well as international customers.

As of March 2026, this pool comprised approximately 26 million spare parts valued at around $31 billion, the GAO reported. 17,000 parts – worth up to $2.5 billion – were not recorded in the Pentagon’s property and logistics management platform, the Enterprise Logistics Management System.

In 2023, the GAO reported that one prime contractor lost more than 1 million F-35 spare parts worth more than $85 million from 2018 to 2022. As of March 2026, the F-35 Joint Program Office still did not know the status of the items.

The F-35 has two prime contractors: Lockheed Martin for the airframe, and Pratt & Whitney for the engines. The U.S. Air Force awarded Lockheed Martin a $1.6 billion contract for more spare parts in July.

Issues still plague inventory tracking systems used by the F-35 Joint Program Office.

“For instance, records of F-35 parts in the F-35 program’s accountable property system of record remain unreliable, since they do not reflect real-time changes and are inaccurate and incomplete,” the GAO report states.

Nor can the Enterprise Logistics Management System track joint spare parts in real-time “because ELMS does not currently interface with the two prime contractors’ property management systems.”

“DoD does not have its own complete records of F-35 parts, and, as a result, does not know when a part is lost unless staff at the contractor-managed or government-managed facility identifies and reports the loss,” Asif Khan, director of GAO’s financial management and assurance team, told Defense News.

For joint spares, the F-35 Joint Program Office relies on data supplied quarterly by the prime contractors, which means that “joint spares pool data in ELMS may be more than 3 months old.” Whether some F-35 spares are actually located where they should be isn’t always clear, in part because the prime contractors aren’t always aware of inventories held by their subcontractors.

Some parts were also valued quite cheaply in the contract data requirements lists, which are submitted by the prime contractors quarterly.

“Almost 6 percent of records of F-35 parts, also from the December 2025 CDRL, showed an acquisition cost of $0.01 or less, also indicating a possible data quality error,” the GAO noted.

“Neither records of F-35 parts in ELMS nor F-35 JPO’s inventory results are reliable for the purpose of asset accountability or financial reporting,” the report states.

Even estimating how many of the 26 million F-35 parts are missing is difficult.

“Because the F-35 JPO has not established and implemented effective procedures for monitoring losses, we are unable to provide an aggregate estimate of how many of the 26 million parts are lost,” Khan said.

The F-35 Joint Program Office should improve its procedures for recording lost parts, “including procedures for performing trend analyses that would enable mitigation of future losses,” the GAO recommended. The office should also make more use of accountable property officers who maintain records of parts, including specific training focused on the F-35 program.

Questions remain whether an inability to track spare parts is hampering F-35 operations.

The GAO warned earlier this year that poor parts accountability is complicating efforts to improve the F-35 program. Customers have also been asking for greater transparency into the supply chain so they can properly allocate resources, Khan noted.

“For several years, we’ve been reporting that DoD cannot ensure that the prime contractor is providing sufficient readiness at a reasonable cost without an understanding of the parts it owns and how the prime contractor manages those parts,” Khan said.