Russia has revealed a new fifth-generation fighter engine, the 177S turbofan, at the Dubai Airshow 2025, positioning it as the successor to the long-running AL-31 family that powers the Su-27 series. As reported by the European Defence Review, it marks one of Russia’s most significant aerospace upgrades in years.
Developed by United Engine Corporation under Rostec, the 177S is designed to slot directly into any fighter using AL-31 variants, allowing air forces to upgrade existing aircraft without major airframe changes. Despite nearly identical dimensions to the older engine, the 177S delivers a major jump in capability.
It produces 14,500 kgf of thrust in afterburner and 9,000 kgf dry, while weighing about 1,530 kilograms. Internally, the engine features substantial improvements. Fuel burn in cruise has been lowered to under 0.67 kg per kgf per hour, enabling longer range. Service life has doubled and time between overhauls has increased fourfold to 1,500 hours, reducing operating costs and maintenance downtime.
The engine also includes thrust-vectoring nozzles for extreme maneuverability, a full-authority digital engine control system with hydromechanical backup, onboard diagnostics, and a newly designed blisk fan that improves resistance to bird strikes and foreign-object damage.
According to the report, the 177S is entering advanced flight testing and is intended for the Su-35S, the Su-75 Checkmate, and most importantly, the Su-57 Felon. In Russian sources, the engine is widely associated with Izdeliye 30, the second-stage powerplant expected to finally give the Su-57 true supercruise and a better thrust-to-weight ratio.
Serial production is targeted within the next two years. The upgrade is strategically important for Russia as it attempts to keep its aerospace sector competitive despite Western sanctions that have strained access to high-end components. Russia has continued advancing its programs through industrial workarounds and partnerships with countries such as China.
The 177S is meant to strengthen Russia’s fighter export prospects at a time when only the United States and China produce fifth-generation jets at scale. If testing continues on schedule, the new engine could become the core of Russia’s combat aviation lineup well into the 2030s.
