Russia tests new engine on Su-57 fighter jet

Russia’s state defense conglomerate Rostec says its Su-57 Felon fifth-generation fighter has completed its first flight using a new fifth-generation engine, known as “izdeliye 177,” marking what the company describes as a new phase in testing for the aircraft.

According to a statement from Rostec, the United Aircraft Corporation and United Engine Corporation have begun flight testing of the “izdeliye 177” engine as part of the Su-57 fifth-generation aviation complex. The company said the flight was conducted in a standard manner and in line with the assigned flight mission.

Rostec said the new engine delivers a maximum afterburner thrust of 16,000 kilogram-force. The company also stated that the engine has reduced fuel consumption across all operating modes and increased service life indicators. According to Rostec, the use of new technologies, materials, and design solutions allowed United Engine Corporation to create a powerplant with more advanced technical characteristics compared with engines from the previous generation.

The Su-57 is described by Russian officials as a multirole fighter designed to carry out a wide range of combat missions. According to Rostec, the aircraft is capable of engaging aerial, ground, and maritime targets and can operate around the clock, including in difficult weather conditions and in complex electronic warfare environments. The company said the aircraft’s low observable features allow it to strike targets even when facing modern air defense systems.

In a statement, Rostec said: “The Su-57 has performed well in real combat conditions and confirmed that it meets the requirements applied to fifth-generation aviation complexes, including in terms of stealth characteristics. The aircraft naturally generates high interest among foreign customers, and export deliveries are already being carried out. At the same time, the Su-57 continues to be modernized taking into account experience from use in the SVO zone: the capabilities of weapons and onboard systems are being expanded. The new engine – ‘izdeliye 177’ – with increased thrust will further improve flight characteristics and provide a large reserve for the further development of the aircraft.”

The Su-57, developed by Russia’s aerospace industry and operated by the Russian Aerospace Forces, has been presented by Moscow as the cornerstone of its future tactical aviation fleet. Russian officials have previously said the aircraft is intended to replace older fighter platforms while offering improved range, maneuverability, and sensor integration.

Rostec’s announcement comes as Russia continues to emphasize modernization of its military aviation programs. The company said flight testing of the new engine will continue as part of the Su-57 development process, though it did not provide a timeline for certification or series production of the “izdeliye 177.”

The introduction of a new engine variant has long been presented by Russian industry as a key milestone for achieving the fighter’s intended performance profile.

Rostec did not disclose how many test flights are planned or whether the new engine will be retrofitted to aircraft already in service. It also did not provide updated figures on current fleet size or export customers beyond confirming that deliveries are underway.