Kawasaki Ki-61 is the only liquid-cooled fighter among Japanese fighters that was active in the Pacific War.

As a result of thorough efforts to reduce resistance and weight, it has been completed as a well-balanced aircraft that can maximize both speed and mobility as expressed by the word mid-war.

Although it was officially adopted in 1943, the Ha40 liquid-cooled engine malfunctioned due to poor production and unfamiliar maintenance due to lack of basic industrial power.

Still, he was active in the Philippines, New Guinea, and the mainland air defense battle.

Especially in the mainland air defense battle, parts were properly supplied, the high operating rate was maintained by the work of veteran maintenance personnel, and the high altitude performance was better than other Japanese aircraft, so we are struggling against the B-29 battle.

In particular, in the 244th Air Squadron, the youngest squadron in the history of the Army, Captain Teruhiko Kobayashi, showed a fierce battle and shot down more than 160 B-29s by the end of the war, boasting the best results of the unit.