kaiten (weapon)

The "Kaiten" (回天, literally "heaven shaker"), was a large manned suicide torpedo based of the infamous Type 93 "Long Lance" employed by the Imperial Japanese Navy for suicide attacks. It is similar to kamikaze pilots, as both were conceptualized during the late stage of World War II in a desperate attempt to slow down Allied force's advance to the Japanese home island.

It was of questionable use and exceptionally dangerous to both those handling them and the pilots; around 200 kaiten trainees, mechanics and hosts (the kaiten were fired from other ships or submarines) were killed while attempting to employ kaitens. Meanwhile, only 3 ships were sunk by the weapon.