GAO Finds Pentagon Cannot Account for 17,000 F-35 Parts Worth $1.3 Billion

The F-35 program includes about 26 million parts, valued at roughly $31 billion and held at more than 700 contractor- and government-managed facilities worldwide, according to the report, numbered GAO-27-108713. The Department of Defense owns the parts but does not keep complete records of them.

The Government Accountability Office said records in the program’s accountable property system, the Enterprise Logistics Management System, are outdated, inaccurate and incomplete. As of March 2026, the F-35 Joint Program Office had not entered about 17,000 parts that were in maintenance or repair into that system. Officials put their value at about $1.3 billion, and said the figure may be as high as $2.5 billion once missing cost data and acquisition expenses such as transportation and overhead are included.

The F-35 is the Pentagon’s most expensive weapons program, with life-cycle costs estimated at more than $1.9 trillion.

Inventory Records Remain Unreliable

The office cannot use the system’s real-time tracking because it still does not interface with the property systems run by the program’s prime contractors, Lockheed Martin and Pratt & Whitney, a gap GAO first flagged in 2022 and said persisted as of August 2026.

Instead, the office updates records of parts in the joint spares pool from contractor data submissions that arrive quarterly, leaving some entries more than three months old. It also lacks full procedures to check the accuracy of that data before it is entered.

A December 2025 contractor submission included serial numbers for only 29% of part records and National Stock Numbers for 43%. Almost 6% of the records showed an acquisition cost of one cent or less, which GAO said pointed to possible data errors.

Physical inventories have not closed the gap. The program office has spent at least $17 million since fiscal 2020 counting parts at contractor- and government-managed sites, but the most recent effort did not fully verify that listed parts were present or that every part on hand was recorded.

GAO said some prime contractor data may be inaccurate, the locations of some sub-subcontractor facilities holding F-35 parts remain unknown, and parts sent for repair or moving through commercial shippers may be left out of inventory records. About 70% of the parts are held at government sites and 30% at contractor-managed facilities.

“Without accurate data in its APSR and properly executed inventory procedures for F-35 parts, DOD management will not have the information it needs to support warfighter readiness and reliable financial reporting,” the report said.

Tracking failures in the wider supply chain have already drawn scrutiny. Clash Report previously reported that F-35 components being sent from Australia to the United States for repair were diverted to Hong Kong, prompting a joint investigation. The new GAO report does not link that incident to the inventory gaps.

Earlier Losses Remain Unresolved

As of March 2026, the program office still did not know the status of lost parts valued at more than $85 million that GAO identified in 2023. That earlier review found that one prime contractor had recorded losses of more than 1 million parts, worth over $85 million, between May 2018 and October 2022, including about 940,000 parts worth more than $66 million that had not been submitted for government review.

By March 2026, the contractor had submitted about $28 million in loss reports covering 2012 through 2025. The Defense Contract Management Agency held the contractor financially liable for about $6 million of that total. Because the program office had not kept records of outstanding cases, it could not determine whether those reports included any of the earlier $85 million, GAO said.

Newer reports showed similar delays. Of 57 loss cases entered into a spreadsheet by April 2026, 24, worth almost $400,000, were filed more than a year after they were discovered, despite a requirement to submit documentation within 30 days.

The office has not established procedures for effectively reviewing losses at government-managed facilities or for analyzing trends that could help prevent future losses, including fraud, waste or theft, the watchdog said.

Readiness Risk and Official Response

GAO warned that weak inventory records could undermine the Pentagon’s $13.7 billion Global Support Solution Reset, a plan to improve F-35 performance that includes raising the supply of spare parts. Without a reliable baseline, the department may be unable to identify what parts it needs, or to account for additional parts bought under the strategy.

Spare-parts accounting has been a recurring weakness in the program. Clash Report has previously reported that Pentagon audits cited F-35 inventory management as a material weakness for a sixth straight year, and that cost disputes have separately led Switzerland to consider cutting its F-35 order.

GAO made four recommendations, including that the Defense Department develop procedures to monitor and analyze losses of F-35 parts, and that it create F-35-specific procedures, training and a clearer structure for accountable property officers. The department concurred with all four and cited actions it is taking to address them.

A Joint Program Office spokesperson told Breaking Defense that the office was “actively working” to address the findings, including new procedures and training, and was “establishing direct, real-time data interfaces between government and prime contractor systems.”

Lockheed Martin referred questions on the report to the program office. A company spokesperson said it was working with the office, the U.S. services and international customers “to improve parts availability, repair turnaround times and supply chain performance,” and pointed to a proposed multiyear procurement and sustainment framework that would still require congressional approval.

The Defense Contract Audit Agency is working with the program office on a full inventory of F-35 parts, with a target completion date of March 2027.