Rapid advancements in unmanned combat aircraft technology raise questions about long-term sustainability of F-35 program ANKARA / ISTANBUL As the US trims its fiscal 2026 F-35 Lightning II purchase from 74 to 47 aircraft, criticism of its soaring costs and concerns over long-term viability amid rapid drone development are gaining renewed attention. Under the Department of Defense’s proposed budget, the F-35 order drops to 47 jets, with funds redirected to fleet upgrades, improved sustainment,