The Kawasaki Ki-61 Hien (Swallow) was a Japanese World War II fighter aircraft used by the Imperial Japanese Army Air Force. The first encounter reports claimed Ki-61s were Messerschmitt Bf 109s: further reports claimed that the new aircraft was an Italian design, which led to the Allied reporting name of "Tony". The Japanese Army designation was "Army Type 3 Fighter". It was the only mass-produced Japanese fighter of the war to use a liquid-cooled inline V engine. Over 2,500 Ki-61s were produced, first seeing action around New Guinea in 1943, and continuing to fly combat missions throughout the war.
This artwork depicts the the "Blue 24" Hien of Maj. Kobayashi. Maj. Teruhiko Kobayashi started his career in the JAAF as a light bomber pilot over China. He rose to fame as a CO of the 244 Sentai defending the skies over Tokyo in 1944/45. Kobayashi's final credit is 14 (20?) kills, most of them B-29s, and although formally not a "shinten" pilot, he scored his 6th victory on January 27, 1945, by ramming a Superfortress. For this merit he received the Bukosho Medal of Honour . He flew several different Hien and the very fact that the many markings of his aircraft are well documented is a confirmation of his popularity.
(Source: Mark Kaiser and Wikipedia)