The first serial fighter-monoplane aircraft of Japan Imperial Army became the Ki-27. The first of two prototypes built by a Nakajima company was flying in October 1936. Series production was ordered in December 1937 as the Type 97 Fighter Model Ko (Ki-27a). Ki-27a had excellent maneuverability and was serious enemy for Soviet-built I-15bis and I-16 fighters in air battles over China and Mongolia in 1938-1939.
