The Sukhoi Su-35 (Russian: Сухой Су-35; NATO reporting name: Flanker-E/M, occasionally nicknamed "Super Flanker" is the designation for two improved derivatives of the Su-27 air-defence fighter. They are single-seat, twin-engine, supermaneuverable, 4.5 generation air superiority fighters, designed by the Sukhoi Design Bureau and built by Sukhoi.