Development of the Su-6 began in 1939, when the Sukhoi design bureau began work on a single-seat armoured ground-attack aircraft. An order for two prototypes was placed on 4 March 1940, and on 1 March 1941 flight testing of the first prototype was begun by test pilot A.I. Kokin. The flight tests indicated that the Su-6 was superior to the
Ilyushin Il-2 in nearly all performance categories, however its engine exceeded its age limit before testing could be completed, and no further
Shvetsov M-71 engines were available. It was armed with two 23 mm cannon, four machine guns and ten rails for aerial rockets. Test results were very favorable, and the
AFRA Scientific Research Institute recommended the acquisition of a small production batch for testing under front-line conditions. A draft resolution for the production of 25 aircraft was prepared, however unfortunately for Sukhoi, it was never officially issued. ==Variants==