Is Russia’s Long Awaited Su-57M Fighter Now Flying? Behind Reports of an Enhanced Variant in Testing

An enhanced version of Russia’s Su-57 next generation fighter was confirmed to have performed its maiden flight on October 21, with this reported by the state owned United Aircraft Corporation days later. Details regarding the new variant were scarce, except for that it flew at the Gromov Flight Testing Institute’s airfield, was piloted by Sukhoi Design Bureau test pilot Sergey Bogdan, and that the aircraft “offers a possibility to install a second-stage engine.” Although Russian sources previously reported that Su-57s would begin to integrate Saturn 30 engines with next generation capabilities in 2022, which itself was a much delayed date with the powerplant initially expected to become operational in the 2010s, this is now not expected to occur before 2025. 2025 is also the year when the Su-57M, an enhanced variant if the fighter, is expected to enter service, with the Saturn 30 expected to be a key feature which separates the ‘M’ variant from the standard one currently in service, potentially indicating that the new aircraft which flew may well be the first Su-57M.

Although initially expected to enter service in 2015, a full decade before the anticipated date, the Saturn 30 first flew only in December 2017, and according to some official statements is expected to be the most powerful fighter engine in the world. While expected to comfortably surpass the American F-22’s F119 engines, however, which existing Russian engines such s the AL-41F1 already come very close to, whether the Saturn 30 will be able to offer a similar performance to the newer F135 powering the American F-35, or the WS-15 now in flight testing for China’s J-20 stealth fighter, remains highly uncertain. The new Russian engine’s reported performance is similar to that of the Soviet AL-41F which reached advanced prototype stages in the 1990s before being cancelled, leading some analysts to conclude that Russia’s indigenous development of engines has made only conservative progress since then with its current powerplants still heavily reliant on Soviet era technologies – which had a strong lead before the state’s disintegration. When integrated onto the Su-57, the Saturn 30 is nevertheless expected to provide the fighter with an unrivalled flight performance and potentially the ability to cruise at speeds exceeding Mach 2 without using afterburners, while also lowering maintenance requirements and operational costs and increasing the aircraft’s endurance considerably. 

Only six Su-57s are currently in service in the Russian Air Force, although the Russian-Ukrainian War has provided several opportunities to test the aircraft in combat against a state adversary – opportunities which America and China’s larger stealth fighter programs have not had. This has included testing the Su-57’s sensors, using it for air defence suppression, and conducting standoff strike missions, as well as a possible unconfirmed incident of air to air combat at extreme ranges against one of Ukraine’s ageing Soviet built Su-27 fighters. The strike operations alone, which official sources have confirmed several times, make the Su-57 the only aircraft of its generation to have completed such missions – while serving to highlight that its American counterpart the F-22 notably lacks any standoff strike capabilities whatsoever. The fleet is expected to exceed 50 fighters in 2026 and reach 76 by the end of 2027, with investments in expanding production ongoing and foreign orders from Algeria in particular having been widely speculated. 

Although formidable, the Su-57 lacks some of the key technologies used on the J-20 and F-35, and its entry into service in meaningful numbers only the mid 2020s leaves Russia behind the industry leaders China and the U.S. It is nevertheless still comfortably ahead of the rest of the world, with the closest other competitor to develop an indigenous post fourth generation fighter being South Korea with its KF-21 program. As China and the U.S. are expected to being fielding their first sixth generation fighters around 2030, Russia is expected to invest heavily in developing the Su-57 into a ‘5++ generation’ fighter with sixth generation technologies. This would mirror its reliance on the ‘4++ generation’ Su-35 to counter the F-22 and F-35. Development of the Su-57M would be a key step towards this goal, with a ‘Su-57M2’ and other successors, possibly even redesigned ‘Su-60,’ expected to emerge by the early 2030s.