US F-35 Fleet Faces Readiness Crisis Amid Parts Shortage

The U.S. F-35 fighter jet fleet is facing a critical decline in operational readiness, hampered by ongoing maintenance problems, a scarcity of spare parts, and technical challenges, according to a new report from the U.S. Congress's governmental watchdog institution.

The F-35 Lightning II program, developed by Lockheed Martin, stands as the most expensive military project in Pentagon history, with total acquisition and lifetime operating costs estimated to exceed $2 trillion.

The Government Accountability Office (GAO) report reveals a deteriorating combat capability for the F-35s. Mission-ready rates, the percentage of time an aircraft can perform at least one operational mission, fell from 67% in fiscal year 2021 to 44% in 2025. Full mission capable rates, indicating an aircraft's ability to execute all its designed missions, plummeted from 38% to just 25%. This means only one in four F-35s was fully prepared for its entire operational spectrum last year.

Key factors contributing to this decline include delays in spare parts delivery, software issues, and extended maintenance durations, leaving a substantial number of aircraft unavailable for prolonged periods. The Pentagon initiated a $13.7 billion modernization and readiness enhancement plan in 2025, aiming to improve fleet preparedness by the end of the decade. However, GAO auditors caution that the program may require additional funding and faces significant risks, such as heavy reliance on private contractors, limited parts production capacity, and escalating operational expenses.

The GAO also scrutinizes the Defense Department's incentive system for contractors. Despite financial bonuses and incentives for improving fleet performance, the current structure does not guarantee that these payments translate into actual increases in aircraft availability. Auditors warn that companies might receive rewards even if the program's operational objectives are not met.