Yokosuka MXY-7 Ohka

By the summer of 1944 the Imperial Japanese Navy could no longer stop American carrier forces by conventional attack, and a transport pilot, Ensign Mitsuo Ohta, proposed a small piloted glide bomb that a bomber would carry most of the way to the target and release within range. The Navy approved the idea in August 1944 and the Yokosuka Naval Air Technical Arsenal, Kugisho, drew it up in a matter of weeks. The Ohka, ‘cherry blossom’, was little more than a 1,200 kg warhead in the nose with a cockpit, short wooden wings and a twin-finned tail behind it, and three solid-fuel rockets in the tail to drive it into a ship in the final dive. It had no undercarriage: it was never meant to land.

Unpowered and powered trials began at Sagami in October 1944, and the Model 11 went into production at Yokosuka and Kasumigaura; about 850 of all versions were built, nearly all of them Model 11s. Each was slung under a Mitsubishi G4M bomber, whose crew carried it towards the target with the pilot climbing down into the cockpit before release. The pilots belonged to the 721st Kokutai, the Jinrai Butai or ‘Thunder Gods’. The heavily laden bombers were slow and vulnerable, and on the first mission, on 21 March 1945, the whole formation was shot down before any Ohka could be released.

The first success came on 12 April 1945 off Okinawa, when an Ohka sank the destroyer USS Mannert L. Abele; a handful of other ships were hit or damaged before the war ended. Once released, an Ohka was very hard to stop, diving at over 550 mph, but few ever came close enough to try. American forces found intact examples when they overran Yontan airfield on Okinawa in April 1945, and their intelligence code name for the type, ‘Baka’, meaning fool, stuck in Allied usage. Several captured Ohkas were brought to Britain after the war, and Model 11s survive in British museums including RAF Museum London and the Fleet Air Arm Museum at Yeovilton.