Fukuryu

Fukuryu (Japanese: 伏龍, Hepburn: Fukuryū^?) were a part of the Japanese Special Attack Units prepared to resist the invasion of the Home islands by Allied forces. The name literally means "crouching dragon," and has also been called "suicide divers" or "kamikaze frogmen" in English texts.

Six thousand men were to be trained and equipped with self-contained diving gear including a diving jacket and trousers, diving shoes, and a diving helmet fixed by four bolts. They would be weighed down with 9 kg (20 lb) of lead and be sustained by liquid food and an air purification system with two 3.5-liter bottles of oxygen at 150 bar (2,200 psi). They were expected to be able to walk at a depth of 5–7 m (16–23 ft), for a period of up to ten hours. Personnel were organized into six-man squads with five squads to a platoon, five platoons plus a maintenance platoon to a company, and three companies to a battalion of approximately 650 men. The 71st Arashi was headquartered at Yokosuka with two trained battalions and four battalions in training. The 81st Arashi at Kure was planned for 1000 men to be trained by 250 men from Yokosuka. A similar 1000-man Kawatana unit was planned for Sasebo.

Men were to be armed with a Type-5 attack mine containing 15 kg (33 lb) of explosive, fitted to a 5 m (16 ft) bamboo pole. While concealed underwater, men expecting to be killed by the resulting explosion would use the pole to push the contact-fuzed explosive against the hull of a landing craft passing overhead. Off each potential invasion beach, an inventory of mines was anchored to the bottom for use by the submerged men. Three strings of mines were fifty meters apart, and men would be stationed sixty meters apart, staggered so there would be a man for each 20-meter length of beach.

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