Late in World War II, the Dai-ichi Kaigun Koku Gijitsusho (1st Naval Air Technical Arsenal) at Yokosuka, Japan, designed the MXY7-K1 to teach less experienced pilots to fly the Model 11 "Ohka" (Cherry Blossom) kamikaze suicide rocket bomb. The Ohka was carried to the target under a G4M "Betty" bomber. When the Betty/Ohka combination reaching Allied shipping, the Ohka pilot would detach, ignite the rocket motor, and dive into a ship.
This trainer version was carried aloft and then released for practice flights. Unlike the Ohka, the MXY7-K1 had a landing skid and flaps. In place of the warhead and rocket motors of the Ohka, the MXY7-K1 used water ballast that was expelled before landing. Even so, it challenged novice pilots with its high, 130 mph landing speed.
A total of 45 MXY7-K1 trainers were completed by the end of WWII.
TECHNICAL NOTES (Operational version Model 11 "Ohka"): Armament: 2,646-lb. warhead Engines: Three Type 4 Mk.1 Model 20 rockets with a total of 1,764 lbs. thrust Maximum speed: 615 mph in a powered dive Range: 55 miles (unpowered glide, 8-10 seconds of rocket thrust for final dive)