KD-1a Kayaba KA-2 KA

The KD-1A Kayaba KA-2 KA were a pair of autogyros, sisters of each other.

In the late 1930s, the Japanese military became interested in auto-gyros for artillery spotting, so in 1939 Japan imported a KD-1A autogyro from the United States. Shortly thereafter, it was damaged beyond repair in flight training, so the Japanese military delivered it to K.K. Kayaba Seisakusho, a small company working on autogyro research. The Japanese military told them to develop a similar autogyro, specifying they must use the Japanese 240 hp Argus 10c engine.

On 26 May 1941, the autogyro performed very well, demonstrating it could take off after only 30 m (98 feet) in still air by holding its tip at 15°, and showing its ability to fly and hover.