The Sukhoi Su57 (Russian: Сухой Су57; NATO reporting name: Felon) is a stealth, singleseat, twinengine multirole fifthgeneration jet fighter being developed since 2002 for air superiority and attack operations.[13] The aircraft is the product of the PAK FA (Russian: ПАК ФА, short for: Перспективный авиационный комплекс фронтовой авиации, romanized: Perspektivny Aviatsionny Kompleks Frontovoy Aviatsii, lit. ''prospective aeronautical complex of frontline air forces''), a fifthgeneration fighter programme of the Russian Air Force. Sukhoi's internal name for the aircraft is T50. The Su57 is planned to be the first aircraft in Russian military service to use stealth technology. Its maiden flight took place on 29 January 2010 and the first production aircraft are planned to be delivered in 2020.

The fighter is designed to have supercruise, supermaneuverability, stealth, and advanced avionics to overcome the prior generation fighter aircraft as well as ground and naval defences. The Su57 is intended to succeed the MiG29 and Su27 in the Russian Air Force.

The prototypes and initial production batch are to be delivered with a highly upgraded Lyulka AL31 variant, the AL41F1, as an interim powerplant while an advanced cleansheet design engine, currently designated the izdeliye 30, currently in final stages of development and expected to be available after 2020. The aircraft is expected to have a service life of up to 35 years