F-35 Mission Capable Rates Reported at 44 Percent in Fiscal 2025

A Government Accountability Office report released in June 2026 examined F-35 aircraft availability across the Air Force, Marine Corps, and Navy fleets. The report found that 44 percent of F-35s met the mission capable standard during fiscal 2025, down from 67 percent in fiscal 2021. The full mission capable rate stood at 25 percent in fiscal 2025, compared with 38 percent in fiscal 2021.

The GAO attributed the declines to spare parts shortages, software issues, maintenance backlogs, and corrosion. The report also noted that the F-35 fleet size and total flight hours have both increased substantially since 2021. The program office stated that sustainment capacity has not expanded at the same pace as aircraft deliveries and operating tempo.

The Department of Defense sustainment strategy sets targets of 80 percent mission capable and 65 percent full mission capable by 2030. The GAO estimated that achieving those targets would require approximately $14 billion in additional funding above current projections. The F-35 program's total estimated lifecycle cost exceeds $2 trillion.

The Pentagon's fiscal 2027 budget request includes funding for 85 F-35 aircraft plus associated support costs, totaling more than $21 billion. The GAO report examined whether current sustainment funding levels align with projected fleet growth through the end of the decade.