Su-37 Super Flanker

The Sukhoi Su-37 (NATO reporting name: Flanker-F) was a Russian single-seat, twin-engine technology demonstrator designed by the Sukhoi Design Bureau. Developed to evaluate thrust-vectoring controls and flight systems for the Su-27M, the aircraft did not enter production, with a single prototype constructed. The aircraft was known for demonstrating high-angle-of-attack supermaneuverability at international flight displays.

Development

Sukhoi initiated research into axisymmetrical thrust vectoring in 1983, running parallel to the Soviet government's development mandate for the Su-27M. The sole prototype was converted from the eleventh Su-27M airframe (factory code T10M-11), manufactured by the Komsomolsk-on-Amur Aircraft Production Association. Due to a lack of funding from the Russian Air Force, Sukhoi financed the project using export revenues from Su-27 sales to China and Vietnam. The aircraft made its first flight on 2 April 1996 from Zhukovsky Airfield, piloted by Yevgeni Frolov. T10M-11 remained the only prototype built throughout the flight-test program.

Design

The Su-37 retained the aerodynamic configuration and canards of the Su-27M. Power was initially provided by two Lyulka-Saturn AL-37FU afterburning turbofans equipped with axisymmetrical thrust-vectoring nozzles capable of pitching 15 degrees up or down. The aircraft utilized a digital fly-by-wire flight control system linked directly to the thrust-vectoring system and full-authority digital engine controls. Avionics included an N011M Bars passive electronically scanned array radar capable of tracking twenty aerial targets and engaging eight simultaneously, an N012 rear-facing radar, and an OLS-35 infrared search and track system. The cockpit was configured with four Sextant Avionique liquid crystal multi-function displays and an ejection seat reclined to 30 degrees to improve g-force tolerance.

Armament

Internal armament consisted of one 30 mm GSh-30-1 cannon with 150 rounds. The airframe featured 12 hardpoints—comprising two wingtip rails and ten wing and fuselage stations—with a total ordnance payload capacity of 8,000 kg (17,630 lb).

Operational History

During its flight-test programme, the Su-37 demonstrated low-speed maneuvers including the "Super Cobra" and a 360-degree loop termed the "kulbit." The aircraft made its international debut at the Farnborough Airshow in September 1996, followed by display flights at the Paris Air Show, MAKS, the International Defence Exhibition in Dubai, and the FIDAE air show in Chile. After the AL-37FU engines reached the end of their service lives, they were replaced with standard AL-31F engines lacking vectoring nozzles, and the flight control system was updated to compensate. The aircraft was entered into fighter procurement tenders in Brazil and South Korea but gained no export orders. On 19 December 2002, the prototype crashed near Shatura when its port tailplane broke off during a high-g maneuver due to structural fatigue; test pilot Yuri Vashuk ejected safely. Systems tested on the Su-37 were later integrated into the Su-30 and Su-35 programs.