Russia announced that its Su-57 stealth fighter has completed a maiden flight powered by a new fifth-generation engine, marking a significant milestone in the aircraft’s long-running development program.

The flight, conducted on December 22, 2025, tested the new engine as part of efforts to move beyond the interim powerplant previously used on the aircraft. According to state-owned United Aircraft Corporation, the engine is designed to improve thrust performance, reduce fuel consumption, and enhance overall combat efficiency compared to earlier configurations.

Video released from the test shows ground preparations, takeoff, and in-flight footage, confirming the successful completion of the trial. Russian officials described the flight as a key step toward serial production and wider deployment of the upgraded fighter.

United Aircraft Corporation also signaled plans to ramp up Su-57 deliveries, aiming to increase annual output well beyond current levels. The move reflects Moscow’s push to modernize its air force amid sustained operational demands and ongoing competition with Western fifth-generation aircraft.

While questions remain among analysts about production capacity and battlefield effectiveness, the successful engine test underscores Russia’s determination to advance its flagship stealth fighter program and accelerate its integration into frontline service.