Polikarpov I-16

The Soviet Union’s I-16 Ishak (“Little Donkey”) was the world’s first single-seat, low-wing cantilever monoplane fighter with a retractable undercarriage – the formula that was to dominate the remainder of the piston-engine era. Remarkably, its designer, Nikolai Polikarpov, worked as a prisoner in Stalin’s Gulag, having been denounced for
“sabotage” over alleged slow progress in aircraft development. The I-16 was one of the aeroplanes that earned his rehabilitation.
First flown in 1933, the I-16 had a metal wing, a wooden monocoque fuselage, and a radial engine. One of the aircraft’s advanced features, a forward-sliding cockpit canopy, was soon discarded because pilots preferred an open cockpit with a fixed windscreen. Armed with two wing-mounted 7.62mm machine-guns, later supplemented by two
more in the fuselage, the I-16 fought on the Republican side in the Spanish Civil War of 1936-39. It was also supplied to the Chinese,
resisting Japanese invaders from 1937.
Late in the 1930s the aircraft was adapted to take a two-stage supercharged engine, thereby creating a second-generation I-16 that entered production in 1939. At the time of the German invasion of the Soviet Union in June 1941, I -16s comprised over 65 per cent
of the Soviet fighter inventory. Although obsolete, the fighter remained in frontline service until 1943.