The Mitsubishi J2M was a Japanese Interceptor aircraft that was used during World War II. It was designed and developed by Jiro Horikoshi. The first flight was on 20th March 1942. Production of the J2M2 began in October 1942. Because of technical problems, service entry was delayed to December 1943; at this time, development of the J2M3, a derivative with upgraded armament, had already begun. All in all 476 (including prototypes) aircraft were produced.