As Japan began to face overwhelming Allied superiority towards the end of WW2 the Imperial Japanese Navy contemplated suicide attacks to stem the allied advance towards the Japanese Home Islands. The "Okha" was the result of studies at Yokosuka's scientific research bureau and an idea by an Imperial Japanese Navy Ensign. Although only a few were used successfully in combat they did cause considerable damage to US Navy warships. Dubbed "Baka" by the Allies - Japanese for "Stupid" or "Idiot", they were none the less hard to stop once launched and the Rocket engines fired in the final approach to an attack on a vessel. Other versions were planned with a Jet Engine but they didn't get past the design or prototype phase before the war ended.
Left to Right - MXY-7 "Okha" replica in the Yakasuni Shrine, Okha captured by the Allies, View showing the Warhead exposed.