The Imperial Japanese Army (IJA) developed the Ka-1 autogyro for reconnaissance, artillery-spotting, and anti-submarine (ASW) uses.

The Ka-1 was based on an American design, the Kellett KD-1A, which had been imported to Japan in 1939 but which was damaged beyond repair shortly after arrival.

From 17 January 1945, ASW patrols were resumed from an airstrip on Iki Island with a maintenance base located at Gannosu Airfield in Fukuoka prefecture.

Eventually, U.S. carrier-based aircraft began to appear even in the Tsushima Strait, so, in June 1945, the Ka-1/Ka-2 units were relocated to Nanao base on the Noto Peninsula in the Sea of Japan, operating from there until the end of the war.

[citation needed] Data from Japanese Aircraft of the Pacific War[1]General characteristics Performance Armament 2x 60 kg (130 lb) depth-charges