More than half of Ukraine's F-16 fighter jets are currently grounded due to maintenance delays, according to a Western source cited by The Wall Street Journal. At the current rate of operations and repairs, the remaining aircraft could be exhausted by the end of 2026. The Ukrainian Air Force has not released official figures on fleet status, but open-source analysis estimates that between 40 and 50 F-16s have been delivered so far, with some held in Europe for training purposes and at least five confirmed lost in combat. A coalition of Belgium, Denmark, the Netherlands, and Norway has pledged approximately 110 additional F-16s, though delivery timelines remain uncertain.

The strain on Ukraine's F-16 fleet stems from multiple overlapping pressures. Heavy use of air-to-air missiles, particularly AIM-9 Sidewinders and AIM-120 AMRAAMs, to intercept Russian cruise missiles and drones has depleted ammunition stocks. Pilots have resorted to firing the aircraft's internal 20mm cannon in some engagements, a less efficient alternative that requires increased ammunition procurement. Concurrently, Ukraine is exploring the use of laser-guided APKWS II rockets as a lower-cost option for countering drones and subsonic cruise missiles, though public evidence of widespread deployment remains limited.

The operational tempo is accelerating as Russia increases its use of jet-powered drones. Open-source reports indicate that approximately 2,000 jet-powered drones were launched against Ukraine in September 2026, up from around 350 in June of the same year. These drones, capable of reaching speeds up to 375 miles per hour, present a more challenging target for Ukraine's interceptor drones and underscore the growing reliance on F-16s for air defense. At the same time, ground-based air defense systems are experiencing shortages in missile stocks, further shifting the burden to fighter aircraft.

Maintenance infrastructure is struggling to keep pace with demand. A contract awarded by the U.S. Pentagon to Belgian firm Sabena Aerospace Engineering for depot-level maintenance of Ukrainian F-16s carries a ceiling of $235.5 million through January 2029, with $69.7 million initially funded. However, maintenance turnaround times in Belgium have stretched to 40 weeks, compared to the typical two to six weeks in the United States. Extended downtime affects the availability of a small fleet, where each grounded aircraft disproportionately reduces combat capacity. The F-16s in service are among the oldest in operational use, having accumulated significant flight hours and requiring increasingly frequent inspections.

Additional challenges include finite airframe lifespan, dependence on a shared supply chain for engines and components, and the need to support both fighter operations and surface-to-air missile systems that also use AMRAAM and Sidewinder missiles. Ukraine continues to receive new F-16s, with Belgium confirming plans to transfer three more before the end of 2026. President Volodymyr Zelenskyy stated that Ukraine is working to expedite these deliveries through an accelerated process, having already received urgent shipments of ammunition from Belgium and Spain.

Alternative Western fighter options remain limited. Ukraine operates aging Soviet-era MiG-29 and Su-27 aircraft, which are easier to maintain in field conditions but are also required for strike missions. A small number of French Mirage 2000-5Fs have been delivered, but in insufficient numbers to offset potential F-16 losses. Sweden has committed to delivering 16 Gripen C/D fighters starting in early 2027, with 16 newer Gripen E models expected from 2029 onward. Until these replacements arrive, the F-16 remains the primary Western fighter capability available to Ukraine, making its sustainment critical as Russian aerial tactics continue to evolve.