Russia says its Sukhoi Su‑57 completed its first flight powered by the new Izdeliye 177 engine on December 22, 2025, a milestone Moscow frames as a key step in maturing the aircraft’s long-delayed propulsion system. 

The flight was announced by the United Aircraft Corporation (UAC) and confirmed by Rostec, which said the test was conducted without incident and in line with the assigned flight profile.

The test used the T-50-2 prototype airframe, part of the original PAK FA development program. 

This aircraft has now flown with four distinct engine configurations, beginning with the Izdeliye 117 (AL-41F1), followed by two iterations of the Izdeliye 30, and now the Izdeliye 177. 

The flight was piloted by Honored Test Pilot of Russia Roman Kondratyev and conducted in overcast winter conditions at an undisclosed test site commonly associated with Su-57 trials.

Incremental Gains, Not a Final Engine

According to the manufacturer, the Izdeliye 177 is an afterburning turbofan producing up to 16,000 kgf of thrust and incorporates efficiency improvements of roughly 7–10% compared with earlier Su-57 engines. 

Service life is stated to exceed 4,000 hours, reflecting a focus on reliability and sustainment rather than a radical redesign. 

The engine uses a two-shaft, low-bypass configuration with thrust-vectoring nozzles and advanced materials such as single-crystal turbine blades and ceramic matrix composites.

While Russian industry presents the engine as enabling improved supercruise and overall performance, the flight marks the beginning, not the completion, of flight testing. 

UAC and engine manufacturer UEC said further trials are underway, with certification and integration expected to take 12–18 months based on current plans.

Production Claims Under Sanctions

UAC linked the engine milestone directly to plans to expand Su-57 production and deliveries. 

Russia currently operates an estimated 20–25 Su-57s, with official targets calling for 76–100 aircraft by 2028 under the state armament program. 

The company said output at its Komsomolsk-on-Amur facility increased in 2025 compared with 2024, with the Izdeliye 177 expected to enter serial production around 2027, potentially supporting annual deliveries of 20–24 aircraft.

Export ambitions were also highlighted. 

UAC has confirmed recent deliveries of Su-57E export variants and says future export aircraft could be offered with the new engine, positioning the Izdeliye 177 as part of Russia’s broader effort to localize production and mitigate sanctions-related supply constraints.