Kaiten

Kaiten
A Kaiten, Type 1, at the Tokyo Yasukuni War Memorial Museum
Type	Human torpedo
Place of origin	Empire of Japan
Service history
In service	1944–1945
Used by	Imperial Japanese Navy
Wars	World War II
Production history
Number built	approx. 420
Variants	Type 1 Type 1 Mod.1 Type 1 Mod.2 Type 2 (prototype only) Type 3 (only a project) Type 4 (approx. 50 produced) Type 5 (only a project) Type 6 (only a project) Type 10 (1+2 or 1+6 produced)
Specifications
Guidance system	Manually piloted with gyroscopic stabilisation and automatic running.
Launch platform	Submarine, surface ship, and coastal bunker

Kaiten (回天^?, literal translation: "Return to Heaven", commonly rendered as "turn of the Heaven's will", "the heaven shaker") were manned torpedoes and suicide craft, used by the Imperial Japanese Navy in the final stages of World War II.

In recognition of the unfavorable progress of the war, toward the end of 1943 the Japanese high command considered suggestions for various suicide craft. These were initially rejected, but later deemed necessary. Various suicide mission vehicles were developed in the Japanese Special Attack Units.

For the Navy, this meant Kamikaze planes, Shinyo suicide boats, Kaiten submarines, and Fukuryu suicide divers or human mines. The Kamikazes were somewhat successful, and the second most successful were the Kaitens.

Research on the first Kaiten began in February 1944, followed on 25 July of the same year by the first prototype. By 1 August, an order for 100 units had been placed.

The very first Kaiten was nothing much more than a Type 93 torpedo engine compartment attached to a cylinder that would become the pilot's compartment with trimming ballast in place of the warhead and other electronics and hydraulics. The torpedo's pneumatic gyroscope was replaced by an electric model and controls were linked up to give the pilot full control of the weapon.