Kaiten (回天) “Heaven Shaker” Manned Torpedo

The Kaiten was a manned torpedo employed by the Imperial Japanese Navy during the last months of the Pacific War. It was constructed by using the propulsion section of the successful Type 93 “Long Lance” torpedo, but with an enlarged forward section containing the pilot and a 3,420 pound warhead. The photograph is of a preserved example at the Yasukuni Museum in Japan.

The Kaiten were carried to the target area on the decks of fleet submarines, which could carry between four and six depending on the type. The pilot could enter the Kaiten while the submarine was submerged, but there was no way to recover the Kaiten once lunched. It was intended to be a one-way trip. The photograph shows I-361 with Kaiten aboard on 24MAY45, she was sunk with all hands eight days later.

A pilot poses with two Kaiten on the forward deck of I-36.

Pilots cheer from atop their Kaiten as their last voyage begins. Note the details of the securing arrangements.

Kaiten secured to the deck behind the conning tower as the crew musters on deck for departure. 89 Kaiten pilots were lost in combat, many before they could be launched. Eight IJN fleet submarines were sunk by American forces while transporting Kaiten to their operating areas.

The first employment of Kaiten was against the U.S. Fleet Anchorage at Ulithi Atoll. A total of eight manned torpedoes were launched from I-36 and I-47 on 20NOV44. One of these struck the oiler USS Mississinewa (AO-59) which emitted a column of smoke visible for miles. This was observed by the parent submarines, and assessed by the Japanese as the destruction of three aircraft carriers and two battleships.

The Mississinewa rolled over and sank, extinguishing the fires. One of the more surreal photographs from the war.

The USS Antares (AG-10) is most famous for sighting one of the five Japanese midget submarines attempting to enter Pearl Harbor on 07DEC41, which resulted in the USS Ward (DD-139) sinking the midget with the first shots fired of the Pacific War. Antares’ war with Japanese minisubs was not finished however, on 28JUN45 she was attacked by a Kaiten launched by I-36 off Guam. By this time she had been fitted with defensive armament, and sank the Kaiten herself with gunfire. An escorting destroyer, USS Sproston (DD-577) sank another, but the I-36 escaped. The strange story of the USS Ward here: https://inchhighguy.wordpress.com/2019/01/23/uss-ward-dd-139-apd-16/

The USS Underhill (DE-682) was the last victim of Kaiten. On 24JUL45 while escorting a convoy she detected a swarm of Kaiten launched from I-53. Defending the convoy aggressively, she depth charged the contacts. As she was passing over a Kaiten she had rammed, she was struck by a second and both exploded. She sank almost immediately with heavy losses to her crew.

The Imperial Japanese Navy intended to launch Kaiten from surface vessels to oppose the anticipated invasion of the Home Islands. They began modifying several ships to carry Kaiten, including destroyers of the Minekazi and Matsu classes, and the Kuma-class light cruiser Kitakami. Kitakami could carry up to eight Kaiten in her final configuration.

The Kaiten were carried on deck atop a rail and roller system. This is a launching trial aboard Kitakami.

The Kaiten were deployed by rolling them off the stern. The launching cradles would then separate, and the torpedoes would then attack the American fleet. The surface ships never launched Kaiten in operationally.

While small models, Kaiten kits have been offered by several manufacturers, including this pair from Fine Molds. Finished model here: https://inchhighguy.wordpress.com/2019/02/12/kaiten-japanese-manned-torpedo-in-1-72/