Japanese called it Hien (飛燕), U.S. called it "Tony"
Ki61-I Tei = キ61 飛燕一型丁 (fuselage mounted Japanese 20 mm Ho-5 cannon x 2 & wing mounted 12.7 mm (.50 in) Ho-103 machine guns x 2)
Tony was the only mass-produced Japanese fighter of the war to use a liquid-cooled inline V engine.
244th Sentai is one the most famous squadron (fighter regiment), based at Chofu Airbase (東京, 調布) in 1945, leading by Major Teruhiko Kobayashi 小林照彥(JAAF's youngest Sentai commander). 244th Sentai protected Tokyo from bombing by ramming the U.S. B-29 Super Flying Fortress. 244th Sentai claimed 73 B-29s shot down plus 92 damaged.
Captain Kobayashi Teruhiko's Tony from 244th Sentai
This Tony maybe Hei version. Ki61-I Hei = キ61 飛燕一型丙
(fuselage mounted 12.7 mm (.50 in) Ho-103 machine guns x 2 & wing mounted German Mauser MG 151/20 20mm cannons x 2)
(Photo from Wiki)