The Sukhoi Su-57 (Russian: Сухой Су-57; NATO reporting name: Felon) [5][6] is a twin-engine stealth multirole fighter aircraft developed by Sukhoi. [7] It is the product of the PAK FA (Russian: ПАК ФА, prospective aeronautical complex of front-line aviation) programme, which was initiated in 1999 as a more modern and affordable alternative to the MFI (Mikoyan Project 1.44/1.42). Sukhoi's internal designation for the aircraft is T-50. The Su-57 is the first aircraft in Russian ... The Su-57, known by its NATO designation “Felon,” is Russia’s first aircraft marketed as a fifth-generation fighter, combining stealth shaping with internal weapons carriage. Rostec has stated that upgraded versions will receive improved engines and updated weapons systems, though no delivery timelines have been provided. However, defense analysts and Western observers have repeatedly questioned the jet’s classification as a true fifth-generation platform. Its radar signature, engine ... The Su-57M1 will use a flatter fuselage and internal weapon bays to further improve stealth capabilities. The aircraft will also integrate a new radar, which may bolster stealth capabilities by reducing its radar signature. The Su-57 was previously the only Russian fighter class to integrate an active electronically scanned array (AESA) radar in its nose cone, with a transition to a new generation of such radars potentially providing major improvements to situational awareness. It remains ... Russia’s Su-57 Felon: A Stealth Fighter with Big Questions to Answer Russia’s Felon is a fifth-generation multi-role fighter aircraft intended to compete with Western stealth fighters like the American F-22 Raptor and F-35 Lightning II.