Su-47 Berkut

The Sukhoi Su-47 Berkut (Russian: ????? ??-47 ??????, lit.?'Golden Eagle') (NATO reporting name Firkin[1]), also designated S-32 and S-37 (not to be confused with the twin-engined delta canard design[2] offered by Sukhoi in the early 1990s under the designation Su-37) during initial development, was an experimental supersonic jet fighter developed by the JSC Sukhoi Company. A distinguishing feature of the aircraft was its forward-swept wing[3] that gave the aircraft excellent agility and maneuverability. While serial production of the type never materialized, the sole aircraft produced served as a technology demonstrator prototype for a number of advanced technologies later used in the 4.5 generation fighter Su-35 and current fifth-generation jet fighter Su-57