The Sukhoi Su-37 was an experimental technology demonstrator developed by the Sukhoi Design Bureau (OKB Sukhoi) in Moscow. Rather than a series production aircraft, the Su-37 was a heavily modified Su-27M (Su-35) airframe, specifically factory number 711. The aircraft was designed to explore the capabilities of super-maneuverability, allowing for rapid pitch and yaw changes and post-stall maneuvers that exceeded conventional aerodynamic limits. This was achieved by combining a digital fly-by-wire flight control system with 2D thrust-vectoring nozzles on both engines.
The airframe was constructed and assembled at the Komsomolsk-on-Amur Aircraft Plant, also known as the Komsomolsk-on-Amur Aircraft Production Association (KnAAPO) or the Yuri Gagarin Aircraft Plant. Located at 1 Sovetskaya Street in Komsomolsk-on-Amur, Khabarovsk Krai, Russia, the plant has been a primary site for Su-27 family derivatives since its founding in 1927. The conversion of airframe 711 into the Su-37 standard took place in the mid-1990s, culminating in the aircraft's first flight on April 2, 1996, departing from Zhukovsky.
Technically, the Su-37 featured a canard-delta configuration with leading-edge root extensions (LERX) to optimize high-alpha maneuvering. It was powered by two Lyulka/Saturn AL-31F-series afterburning turbofans equipped with thrust-vectoring capabilities. While specific thrust ratings for the prototype variant were not documented, the aircraft was designed as a multirole air-superiority fighter concept. Performance estimates, inferred from the Su-27M family, suggest a maximum speed exceeding Mach 2 (approximately 2,400–2,500 km/h), a service ceiling of roughly 17,000–18,000 meters, and a maximum takeoff weight in the range of 34–35 tonnes.
Despite its technical achievements, the Su-37 never entered series production and was never adopted for operational service by the Russian Air Force or any other military entity. It remained a testbed operated exclusively by Sukhoi OKB and associated flight-test organizations. Consequently, the aircraft saw no combat service. The single prototype is no longer airworthy, and there are no known operational Su-37s remaining today. Its legacy persists through its influence on subsequent Russian fighter programs, including the Su-30, Su-35, and Su-57.