In the mid-1990s, a plane from the “new” Russia attracted attention in aeronautical magazines and air shows. The model was the most modern of Russian fighters, and as much as it resembled an old one known from that country, it promised to deliver much more. Its maneuverability shocked spectators and fueled heated discussions among enthusiasts and onlookers. The name of this plane? Sukhoi Su-37.
In the previous decade, the Sukhoi OKB design studio embarked on a mission to improve the then Soviet Union's best fighter, its own Su-27 Flanker (as it is called by NATO). Through the Su-27M project, also called Su-35 Super Flanker (1st generation of the Su-35 that flies today), the Flanker would receive several upgrades, including new engines, avionics, armaments, a new weapons management system, increased maneuverability and a more robust construction, among other new features.
Internally, the jet was called T-10M, since the Su-27 itself was already designated T-10 by Sukhoi since the conception of its project. Together with the Komsomolsk-on-Amur Aircraft Production Association (KnAAPO), Sukhoi began production of the first Su-35 in 1987. Under the command of test pilot Oleg Tsoi, the T-10M-1 made its first flight in June 1988, and more prototypes followed.
At the same time, the USSR was also carrying out studies to improve the maneuverability of planes in a pre-stall regime, that is, at very low speed, where the control surfaces lose authority. Specifically, the research focused on thrust vectoring, which, in short, transforms the engine nozzles into mobile assemblies, directing the thrust and greatly increasing the aircraft's maneuverability, despite its complexity.
During testing of the Su-27M, test pilots observed difficulty maintaining control of the plane at low speeds and higher angles of attack. From this, the engineers began to develop a new improvement to the Super Flanker, where the main improvement would be the addition of Saturn AL-31FP engines, with movable nozzles.
The project went ahead and the 11th T-10M prototype was chosen for conversion. The modifications, however, were not limited to engines with vectored thrust.
Starting with the cockpit, the Su-37 received four color multifunctional displays, manufactured in by Sextant Avionique (today part of the Thales Group), and complemented by a Head-Up Display (HUD).
To follow the change from the analogue to digital fly-by-wire system, the joystick became a sidestick, installed on the right side, similar to that found in fighter jets. like the F-16 Fighting Falcon. In another similarity with the North American jet, the ejection seat was tilted at an angle of 30º, improving the pilot's resistance to G loads.
Moving on to weapons systems, the Su-37 had 12 hard points on the wings and fuselage, to carry air-to-air, air-to-ground and anti-ship missiles, smart or free-fall bombs, rockets and electronic countermeasure systems. On the right side, the now traditional GSh-301 cannon, caliber 30mm, completed the armaments.
The main sensor was the N011M Bars ive electronically scanned array (PESA) radar, capable of tracking 20 aerial targets at around 140 kilometers, and engaging eight at the same time. Later, this same radar was installed on Su-30 series fighters. In addition to Bars, the pilot had the OLS-27K infrared search and track sensor (IRST), a type of ive radar, which detects aircraft without emitting signals, using only their heat signature.
Carrying the registration number 711 blue (later transformed into 711 white), the Su-37 made its first flight on April 02, 1996. The fighter, which was actually a technology demonstrator, received a camouflaged paint job in shades of yellow and brown and began an extensive campaign of test flights.
The great highlight of the Su-37 was its maneuverability, a characteristic that was already recognized in the Su-27 itself and which was expanded in the Terminator. The fighter could perform extremely tight loops, skids in the air and maintain full control in low-speed aerobatics, almost stopping in the air, as in the “Super Cobra”, a variant of Pugachev's Cobra maneuver.
The Flanker-F, as it was designated by NATO, made its debut at an international air show in the 1996 edition of the traditional Farnborough, in England. The Russian jet impressed the public with its bold maneuvers, never seen before. A year later, at the Paris Air Show, the Su-37 stole the show on the last day of the event, performing four exciting demonstrations.
The White 711 was the sensation of Russian aviation in the 1990s, synonymous with combat power and, once again, aerobatics that other fighters could not perform. Some maneuvers could favor the use of weapons or even change the balance in close aerial combat.
In 1998, the Su-37 ed through Brazil, on its way to FIDAE in Chile. Accompanied by a Su-30MK fighter and an Il-76 freighter, the Flanker-F landed in Recife and also made a stop at Anápolis Air Base, where Mirage III pilots from Brazilian air force got to know the powerful Moscow jet up close. At the time, the FAB was looking for a new combat aircraft through the FX Program and Russia offered its planes. The program, however, ended up being canceled years later.
Subsequently, Sukhoi made changes to the Su-37, replacing the thrust-vectored engines with equipment with “normal” nozzles. In the cabin, the four displays went out and three larger liquid crystal screens came in. Even with the change of engines, the Terminator's maneuverability remained virtually unchanged, through updates to the Fly-By-Wire software.
Despite the plane's capabilities and the impact the model had on the public, the Su-35/Su-27M and Su-37 never won over customers. Finally, on December 19, 2002, the story of the Su-37 would come to an end with an accident. During a test flight in the Zhukovsky region, the horizontal stabilizer on the left side ended up breaking in the middle of a maneuver. Out of control, the fighter crashed; test pilot Yuri Vashuk ejected safely.
The investigations pointed to structural fatigue as the cause of the component failure. Fatigue, in turn, was caused by years of test flights with high-load maneuvers, which finally took their toll.
Even with the loss of the Su-37, its story was not in vain. The important data and knowledge learned from the technology demonstrator served as the basis for the development of even better fighters, such as the Su-35S Flanker-E, which today is among the best active fighter aircraft in the world.
