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Under Water Warfare The Struggle Against the Submarine Menace 1939 -1945
Human Torpedos

Human Torpedoes, X-Craft, and Midget Submarines
Under water craft, or weapons that fall outside the parameters of the conventional Submarine will be discussed in this section, under their country of origin.

Human Torpedoes

(d) Italy
The Italian 2 man Torpedo was carried on the deck of a Submarine, and was 21 inches in diameter, 22 feet long with a 500 pound explosive detachable head.

The 2 propellers were battery driven, and compressed air tanks were fitted to control the depth keeping mechanism. The device was maneuvered below the target ship's keel, the warhead being attached by lines fastened to a clamp attached to each side of the ship under attack Dangling below the keel line, this warhead was usually set to explode in about 2.5 hours time.

Italy used 2 man Human torpedoes in September 1941, when they slipped into Gibraltar harbor and blew up the Tanker "Denbydale," the Cargo ship "Durham," and the Tanker "Fionashell".

The Italian Frogmen manning their human Torpedoes named their craft "Pigs." They were ridden astride by the two man crew, at a speed of only 3 knots over a range of 16 miles.

On the 18th of December 1941, three two-man Torpedoes were launched from the Italian Submarine "Sure," off Alexandria. The Royal Navy Battleships "Valiant," and "Queen Elizabeth," and a Tanker were all damaged. All the Italian Frogmen were captured. Admiral Cunningham commented "One cannot but admire the cold blooded bravery of these Italians."

The "Queen Elizabeth" was attacked a second time in May 1942, whilst she was in a floating dock at Alexandria, but all three crews were forced to abandon their craft and they were all captured.

In all, Italian attacks numbered 7. The results were 14 Allied Ships sunk or damaged.

(b) Japan
By the Spring of 1943, the Japanese had designed a Human Torpedo "Kaiten," or "Heaven Shaker." It had a speed of 40 knots and carried an enormous 3,000 pound warhead. This weapon was successfully tested in July 1944. Although it was easily detected whilst on the surface, and after submerging it left behind a most discernable wake Crews found it hard to steer, and at most, six hours was the ultimate operational time.

Kaiten submarine


The Navy had no difficulty in obtaining volunteers to man this Suicide weapon. They exceeded the supply of "Kaitens." In November, 1944, three Submarines, I36, I37, and I47, each with 4 "Kaitens" carried on deck, strapped in racks, two forward, and two aft, prepared to attack U.S. ships. I37, in the Palaus, and I36, and I47 at Ulithi.

At Ulithi 3 "Kaiten" left I47, the U S Destroyer "Case" was outside the lagoon with 3 heavy Cruisers and a further 3 Destroyers enroute to Saipan.

A periscope was sighted from "Case" and it was assumed that it belonged to a Midget Submarine, this new "Kaiten" weapon still unknown to Allied forces.

"Case" was able to ram the "Midget" breaking it into two pieces. Within the lagoon chaos reigned, as the Cruiser "Mobile" made contact with what they believed to be "Midget" Submarines. Many ships opened fire, and at 0545, (5 45A.M.) the Tanker "Mississinewa" carrying fuel oil, diesel oil and a large quantity of aviation gas blew up with a tremendous roar. Later, her 5 inch magazine exploded, and she finally sank. 50 Officers and Men died. The "Kaiten" had claimed it's first victim.


[ click for enlarged photograph ]

I36, had no such success. Three of her four "Kaiten" jammed within their racks, and could not be released. The fourth departed never to be heard from again.

Other attacks at Guam and Hollandia were inconclusive.

In July 1945, the U.S. Destroyer "Underhill" was despatched by a "Kaiten" killing 113 of her crew.

I58 which sank the Cruiser "Indianapolis" carried "Kaiten" on board, but her Captain, Lieutenant Commander Hasimoto reported at the courtmartial of the Commander of "lndianapolis," Captain McVay, U.S.N. that he had used conventional Torpedoes to sink her. This fact was disputed by some U.S. authorities who strongly believed that "Kaitens" were used to sink this U.S. Cruiser.

The dropping of the Atomic bombs prevented implementation of the Japanese plans to use all their "Suicide" weapons, including "Kaitens" in the final defence of their Homeland. All in all, a great deal of effort, planning, designing, building, and training "Kaiten" crews brought but a small return for their limited use.

(c) Britain
`operational training for a two man Torpedo, known as a "Chariot or "Jeep," the intrepid crew were "Charioteers" and dressed in Frogman outfits.

Their name indicating that they rode the Torpedo sitting astride, one behind the other. A later version of the "Chariot" had recessed seats in tandem but the crew were still exposed to the open sea.

The torpedo rudder was controlled by means of a short joy stick which moved left or right for turning, and fore and aft to control diving or rising through the hydroplanes. A combined starter and throttle had four positions, three to move ahead and one for astern. Top speed was but a slow 3.5 knots.

Two pump levers pumped water in or out of ballast tanks, or moved water from the forward tank to the aft tank or vice versa. A final lever could open or shut the main ballast tank, and compressed air would expel this water via a valve.

The two crew, the front one known as Number 1, controlled the "Chariot." His Number 2 sitting behind him became operational on arrival at the target. Powerful hand magnets were used to position the "Chariot" after coming alongside the target submerged, and then used by the Number 2 to secure the detachable warhead to the ship's bottom.

It was planned to use "Chariots" to attack the "Tirpitz" in October 1942, whilst she was located at Trondhjemfjord in Norway. It was then reported that she had moved further South.

A fishing boat "Arthur" with a Norwegian Skipper was prepared. She would stow two "Chariots" on deck until they reached the proximity of the Norwegian coast. The "Chariots" would then be placed on tow, and "Arthur" would sail through German controls with the "Charioteers" concealed in a hollowed out "Hidey hole" in the peat cargo.

With the "Chariots" under tow and submerged, "Arthur" came alongside the German examination boat, a Control Ofticer came aboard, but the vessel passed his scrutiny. When the party was within striking distance of their objective, both "Chariots" broke away from their tow, and were lost. The "Arthur" was holed and sunk, and the crew and the "Charioteers" all landed and managed to pass into Sweden, but one of the "Chariot" team, Able Seaman Evans was badly wounded in a shoot out near the frontier. On Hitler's orders, he was later shot.

Further "Chariot" operations were undertaken in the Mediterranean, including reconnaissance of the coast of Sicily prior to the invasion, and the sinking of an Italian Cruiser at Palermo. The final operation was an attack in the harbour of La Spezia, ironically, the actual birth place of the Italian two man Torpedo.

Lieutenant Causer and Seaman Harry Smith managed to sink the 10,000 ton Italian Cruiser "Bolzano," but had to abandon their craft, and they then scrambled ashore having been at sea for over 7 hours. The two British sailors joined up with Italian guerillas, with whom they fought for 6 weeks, finally being captured by a German patrol.

It was suspected that they both were responsible for the sinking of the "Bolzano," however they both denied any involvement in that affair, maintaining they were survivors from a large British Submarine. Smith was sent to prison camps in Germany, at first to Bremen, and then to Lubeck, where he was kept in solitary confinement, whilst the Germans tried to break him down to admit that he was involved in the sinking of the "Bolzano", but he managed to stick to his claim that he survived the sinking of a large British Submarine. Smith survived the war, to be finally rescued by the invading British troops.

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