Pentagon watchdog blames Lockheed for poor F-35 maintenance

The U.S. fleet of F-35s, the most sophisticated stealth fighter jet in the world, was only available to fly half of the time because of poor maintenance by Lockheed Martin Corp., a government watchdog said.

The average availability rate of F-35s throughout fiscal year 2024 was just 50% partly because the Pentagon “did not consistently hold Lockheed Martin accountable for poor performance related to F-35 sustainment,” according to a report from the Defense Department’s Office of the Inspector General.

While “the aircraft were not available to fly half of the time” and the maintenance meant the jets didn’t meet “minimum military service requirements,” the Pentagon still paid Lockheed $1.7 billion without any economic adjustment, according to the report, issued on Dec. 19.

The audit is only the latest negative assessment of the F-35, a $2 trillion program that is the costliest Pentagon acquisition effort and has been beset by quality defects, engine issues and concerns around reliability.

In June, the Air Force slashed in half the number of F-35s it was requesting for 2026 as a result of the rising cost of upgrades to avionics and computing power. A blistering report from the Government Accountability Office in September highlighted that the Pentagon still paid Lockheed on-time payment bonuses when it delivered planes as much as two months late, with many jets beset by flaws that would take years to fix.

Defense Secretary Pete Hegseth has ramped up scrutiny of the F-35 program. President Donald Trump has also raised pressure on major defense contractors to invest more in innovation rather than stock buybacks and executive compensation.