su-37

The Sukhoi Su-37 (NATO reporting name: Flanker-F) is an experimental single-seat, supermaneuverable multirole jet fighter, designed by Sukhoi.

A further development of the original Su-27 "Flanker", it was modified from the first-generation Su-35 (formerly "T10M") prototypes. The Su-37 features an upgraded avionic suite and fire-control system, but its most notable additions are the thrust-vectoring nozzles. Only two prototypes were converted.

During the Su-35 flight test programme, active controls during dogfighting maneuvers could not be attained. At the same time, Sukhoi was exploring the application of thrust-vectoring nozzles for fighter jets, giving it better dogfighting attributes.

Throughout the entire program, the Su-37 demonstrated its potential to prospective operators at numerous air shows, performing maneuvers which were previously thought as impossible, among which was a 360° somersault. Despite its potential tactical advantage, the Su-37 did not enter production, and instead remained as a technology demonstrator for updated Su-27 family aircraft such as the export Su-30 and the Su-35BM.