***INFO FROM BOOKS AND WIKI *****
Guns: 2 × 20 mm fuselage-mounted Ho-5 cannons, and 2 × 12.7 mm (.50 in) wing-mounted Ho-103 machine guns
580 km/h (313 kn, 360 mph) at 6,000 m (19,700 ft)
On 25 July 1945, 18 Ki-100 fighters from 244th Sentai encountered 10 Hellcats of the light aircraft carrier USS Belleau Wood's Fighter Squadron 31 (VF-31) in an air battle where the Ki-100 pilots claimed 12 victories with only two losses. Claims and counter-claims regarding the "true" results still arise around this action. The American claims were two Hellcats and two Ki-100s, including Major Tsutae Obara's Ki-100 and Ensign Edwin White's Hellcat which collided, killing both pilots.
The last loss of a Ki-100 occurred on 14 August 1945, a day before the surrender of Japan, when Sergeant Major Fumihiko Tamagake of the 244th Sentai was shot down by a Mustang.