The Sukhoi Su-57 (Russian: Сухой Су-57; NATO reporting name: Felon) is a single-seat, twin-engine stealth multirole fighter developed by Sukhoi. The aircraft is the product of the PAK FA (Russian: ПАК ФА, short for: Перспективный авиационный комплекс фронтовой авиации, romanized: Perspektivnyy Aviatsionnyy Kompleks Frontovoy Aviatsii, lit. ''prospective aeronautical complex of front-line air forces'') fighter programme, while Sukhoi's internal designation for the aircraft is T-50. The Su-57 is the first combat aircraft in Russian military service designed with stealth technology.
A multirole fighter capable of aerial combat as well as ground and maritime strike, the design incorporates stealth, supermaneuverability, supercruise, integrated avionics, and substantial internal payload capacity. The Su-57 is intended to succeed the MiG-29 and Su-27 in the Russian military aviation arms and form the basis for a family of stealth combat aircraft that would replace those of earlier generations. After a protracted development due to various issues that emerged during trials, including the destruction of the first production aircraft in a crash before its delivery, the first aircraft entered service with the Russian Aerospace Forces (VKS) in December 2020. The fighter is expected to have a service life of up to 35 years.