The Kawasaki Ki-100 was a fighter aircraft of the Japanese Imperial Army Air Force, that was used in World War II. Its Army designation was Army Fighter Type 5 (五式戦闘機). Alongside with the Ki-84 Hayate the Ki-100 was one of the best Fighter aircraft in World War II. It was developed from the Kawasaki Ki-61-II-KAI and was powered by a Mitsubishi-Ha112-II-radial engine with a power of 1120 kW. The first flight was on 1st February 1945 and it entered service in March of the same year. The last derivative, the Ki-100-Ib, was used in the last few weeks of the War.