The Kawasaki Ki-61 is a Japanese fighter aircraft developed during World War II. It was designed by Kawasaki Heavy Industries and first flew in 1941. The Ki-61 is notable for its distinctive inline engine, which gave it a sleek appearance similar to European fighters. It was primarily used by the Imperial Japanese Army Air Service. Equipped with a combination of machine guns and cannons, the Ki-61 was effective in dogfights and ground attack missions. It served in various roles throughout the war, including as a bomber escort and interceptor. The aircraft was well-regarded for its performance and agility in combat.