Human torpedo
The human torpedo (originally known in Italian as the Siluro a Lenta Corsa - "Slow-running torpedo") was an electrically propelled torpedo with two crew sitting astride the device and provided with instruments to control and navigated. The warhead was detachable and was used as a limpet mine. The crew wore diving suits while operating the device.
In operation the torpedo was carried to the approximate location of the target by another vessel, typically a normal submarine and then launched. It made its way to the target and the crew attached the warhead. They then used the remainder of the chariot to escape.
The idea was first successfully applied by the Regia Marina early in World War II. Its operators nicknamed it maiale ("pig") because its first model was difficult to steer, while the British nicknamed it the "underwater chariot". The idea was not new, a British inventor - Commander Godfrey Herbert - had patented a manned torpedo design in 1909. It had been rejected as dangerous and unworkable by the War Office during World War I.
Italian Operations
The first attack of the Decima Flottiglia Mas under Ernesto Forza was on elements of the Royal Navy at Alexandria on 19th December 1941. The battleships HMS Valiant and HMS Queen Elizabeth were both severly damaged and out of operation for months. The Italians also carried out raids against shipping at Gibraltar using the merchant ship Olterra anchored at Algeciras with an underwater door to get within range of the harbour, and against shipping in Algiers Bay after the Allied North African landings.
British Operations
The British human torpedo was developed in a direct response to the Italian successes.
Men were recruited in secrecy by Commnders G. M. Sladen and W. R. "Tiny" Fell. The first group was gathered in April 1942 as the Experimental Submarine Flotilla at 'Fort Blockhouse'. A working chariot had not been built although Italian models, more-or-less damaged, had been recovered at Gibraltar. Initially the men had to be trained on a towed wooden dummy called Cassidy.
The men were first trained at Portsmouth in helmet diving and shallow water diving dress before going on to a variant of the DSEA (Davis Submarine Escape Apparatus), an oxygen rebreather which was developed almost in parallel by the Admiralty Experimental Diving Unit.
In June 1942 the sixty strong group was moved to a permanent base, Port D, on Loch Erisort with the submarine HMS Titania. This was to coincide with the arrival of the first powered chariot. Built around a 21-in torpedo and fitted with a 600 lb warhead the 'Mark I Chariot' was capable of 2.9 knots for six hours and could safely operate at a depth of around twenty feet. The training was tough, the stresses of diving and the unknown qualities of the chariots meant many men experienced unconsciousness and convulsions during their stint, the toxic depth of their oxygen based kit was around thirty feet. Lesser complaints such as burst eardrums and sinus problems were common. Training began with simple operation, moved on to navigation and endurance, then to cutting through anti-submarine and anti-torpedo nets set up by the Boom Defence Department, and finally target approach and attack. Setting and attaching the warhead proved specially troublesome.
In August the charioteers were moved to Base HHZ on Loch Cairnbawn, for training on larger, deeper and more heavily defended targets. One charioteer died during these exercises.
First Operation
The first attack operation was initiated by the Norwegian naval officer Leif Larsen in September 1942. He was seeking an attack on the Tirpitz, then in Asenfjord off Trondhiemdfjord. A fishing boat, Arthur, was prepared with mooring gear beneath the hull for towing two chariots and a concealed compartment onboard. After practise attacks on HMS Rodney in early October the fishing boat set out on October 26, 1942 with seven charioteers and three Norweigans.
Arthur reached the Norwegian coast on the 28th, near Edøy, and proceeded up the coast. On the morning of the 30th the chariots were put under tow, despite engine problems the ship reached Hestvik that night and, after repairs, continued. On the 31st, in poor weather, the vessel lost both chariots when the holding bolts sheared.
The mission abandoned, the crew proceeded to Breivik, sinking the Arthur on November 1. Spliting into two groups they made for Sweden. Nine made it, one was wounded in a clash with German troops, captured and hospitalized, he was later shot as a spy.
First Success
In late November 1942 twenty-six charioteers were sent to Malta to be part of the Tenth Submarine Flotilla. Three submarines were fitted with external containers to hold chariots.
The loaded submarines departed from Malta on December 28-29 as Operation Principle. One was sunk but the remaining two, and five chariot teams, reached the Sicilian coast near Palermo in rough weather on January 3, 1943.
One team attacked the recently launched 13.5-mm cruiser Ulpio Traiano, successfully attaching their charge they placed smaller charges on four other vessels. They tried to escape but a failing compass left them lost in the harbour and they had to abandon the chariot. Another chariot successfully attached to the Viminale a 8,500 ton cargo vessel, had to abandon their craft and were captured. The remaing three suffered mechanical, electrical, or human failures and did not complete their attacks. One charioteer was lost and six were captured.
The Ulpio Traiano was sunk and the other vessels attacked suffered varying degrees of damage. Viminale was later torpedoed and sunk while being towed out of the harbour.
Tripoli
Eight charioteers and two chariots remained on Malta. On January 18-19 they were dispatched to immobilize the 'blockships' being prepared for Tripoli in the face of the advancing British Eighth Army.
Carried by submarine the two chariots launched under cover of a RAF raid. One chariot suffered damaged hydroplanes on launch and was abandoned to the south of Tripoli and the two crew later captured. The second craft arrived to find the 'blockships' already in place and after attacking a small merchantship they abandoned their chariot and were soon taken prisoner.
The first Malta operations were ended and new recruits were taken on in January 1943 for training at Loch Corrie and Loch Cairnbawn. In April a new complement of fourteen was sent to Malta. Lacking offensive operations the crews were used in a number of reconnaissance approaches to the beaches of Sicily in May-June. The crews then took on other diving responsibilities.
The Malta group was boosted by a further six teams in late June. An attack on Taranto was planned. It was cancelled a few days before the start date. With the surrender of the Italian fleet all chariot teams were returned to Scotland.
La Spezia
The only other chariot operation in the Mediterranean was on June 21-22 1944. The men attacked the Italian cruisers Bolzano and Gorizia in German hands at La Spezia. Two crews were transported to near the harbour by the destroyer Grecale and then modified MTBs took the chariot to within three miles. One chariot was found to be leaking from her trim tanks and was abandoned. The other made the harbour, passed through three damaged torpedo nets and successfully attacked the 10,000-ton Bolzano. Both teams successfully left the area and joined up with a partisan group, one man made it through to the Allied lines and the other three were captured.
Phuket
In May 1944 the active chariot teams were transferred to the Far East. They were equipped with the Mark II Chariot, the 'Terry'. These were capable of 4.5 knots and had a range of around 30 miles, the warhead was upgraded to hold 1100 lb of Torpex.
The charioteers' targets were two 6,000-ton merchant vessels in Phuket Harbour. Two chariots made the attack run on October 27-28, carried to within six miles of the harbour by a submarine. With little harbour defences both chariots made successful runs and returned safely.
This was the last chariot operation. See this link for technical details about the chariots and the men's diving gear.
Source: Above Us The Waves, C. Warren and J. Benson (Harrap 1953).
A film, Above Us the Waves, was released in 1955, it concentrates on the midget submarine attack on Tirpitz.
The film The Silent Enemy (released in 1958) does not represent real events accurately. In particular, in the real world there was no attack on the Olterra, and no underwater hand-to-hand battle between Italian and British frogmen. The breathing sets used by the film actors representing the Italian frogmen seem to be British naval type rebreathers and not authentic Italian rebreathers.
After 1945
Some nations including Italy have continued to make and keep chariots after 1945.
There are three chariots on public view in Eden Camp Museum near Malton in North Yorkshire in England.
- One is a captured Italian maiale.
- One is an original British Mark II which was found derelict in a scrapyard near a navy base and restored. In that make its two riders sat back to back.
- One is a working chariot that was made recently with the outside appearance of a British wartime Mark I, but its internal working parts are different. It has been filmed in action for the television.
The chariot seen in the James Bond film "On Her Majesty's Secret Service" was a realistic-looking but non-functioning film prop.