Fukuryu

Suicide divers (Japanese:伏龍, "Fukuryu" "Crouching dragons") were a part of the Special Attack Units prepared to resist the invasion of the Home islands by Allied forces. They were armed with a mine containing 15 kilograms of explosive, fitted to a 5 meter bamboo pole. They would dive and stick the pole into the hull of an enemy ship, destroying themselves in the process. They were equipped with a diving jacket and trousers, diving shoes, and a diving helmet fixed by four bolts. They were typically weighed down with 9 kg of lead, and had two bottles of compressed air at 150 bars. They were expected to be able to walk at a depth of 5 to 7 meters, for about 6 hours. Since the invasion of Japan mainland did not occur, this weapon was never used in actual fights.

Several deaths occurred during training due to malfunctions.