Kaiten, WWII Japanese Suicide Torpedo

The name "Kaiten" means "to make a radical reverse in the course of events". The Japanese hoped that this new secret weapon would have just such an effect on the course of the Pacific war in 1944. Kaiten was basically an enlarged torpedo with a small cockpit, a periscope, and manual controls for steering, speed, and depth. It has a pure oxygen-fed, kerosene-burning 550 horsepower engine and a huge 3,000-pound explosive warhead, which could be detonated on impact or by an electrical switch controlled by the pilot. At top speed, Kaiten would travel 75 feet in just under one second. Kaiten were transported by submarine to "firing position" (3.5 to 4.5 miles from the target). A telephone line leading into each Kaiten allowed the submarine's captain to provide last minute pre-launch instructions regarding course, depth, and speed to help guide each Kaiten pilot to his target. As the securing cables were released, the telephone line would disconnect, leaving the pilot on his own to start his torpedo's engine and guide it on a collision course with the target. The upper hatch of a Kaiten was intended to be used as an escape device when the pilot was within 150 yards of the target. It is believed to have never been used as such. In all, 96 Kaiten pilots died (16 in training). The only Kaiten known to have suck a US Navy ship was piloted by LTJG Sekio Nishna, who hit the fleet oiler USS Mississinewa (AO-59) at Ulithi on 20 Nov 1944. In his craft he carried the ashes of his friend, Lt Hiroshi Kuroki, who had been killed during Kaiten training. Nishna and Kuroki were the two junior officers who invented Kaiten. One merchant ship, SS Canada Victory, is believed to have been sunk to Kaiten. One other ship, USS Underhill (DE-682), was scuttled after being severely damaged by Kaiten.