History

During the 1930s, the Italian Royal Navy developed an innovative underwater assault craft known as the Siluro a Lenta Corsa (SLC), more commonly referred to as a human torpedo or Italian Chariot. Conceived by two Italian naval officers in 1935, the electrically powered vehicle was designed to carry two divers covertly beneath the surface to enemy ships anchored in harbour. The Italians gave it the nickname Maiale, meaning pig, to protect the secrecy of the vessel during its initial development.

The craft measured approximately 4.3 metres (14 feet) in length and 0.75 metres (2.5 feet) in width. Powered by rechargeable batteries driving an electric motor, it could operate for around six hours at a maximum speed of approximately three knots. The crew, equipped with closed-circuit oxygen breathing apparatus, rode astride the vehicle, with one acting as pilot and the other responsible for attaching the detachable explosive warhead beneath an enemy vessel. Once secured, the crew would withdraw before the timed charge detonated.

Specialist Italian naval units employed these craft with considerable success against Allied shipping throughout the Mediterranean during the Second World War. Gibraltar became one of their principal targets. Early operations involved launching teams of three chariots from the submarine Scirè, allowing the crews to approach the Bay of Gibraltar covertly before attempting to penetrate the harbour's anti-submarine defences.

Later missions were conducted from the Italian merchant vessel Olterra, which had been scuttled in Algeciras following Italy's entry into the war before being salvaged and berthed in the Spanish port. Under the appearance of routine repair work, the ship was secretly converted into a concealed operational base. A submerged opening was cut through the hull, enabling assembled chariots to leave the vessel underwater before carrying out attacks against Allied shipping anchored in Gibraltar. After completing their missions, the operators returned to the Olterra, making these operations significantly more effective than the earlier one-way attacks.

Following Italy's surrender in 1943, efforts were made to conceal the vessel's clandestine role. Nevertheless, the Royal Navy eventually gained access to the Olterra, where one operational chariot was recovered and restored. Lieutenant Lionel "Buster" Crabb, serving in Gibraltar as a mine disposal officer, placed the recovered craft back into working order and nicknamed it "Emily."

Crabb had arrived in Gibraltar in 1942 and quickly became involved in underwater defence operations despite having only recently completed his specialist demolition training. Determined to improve his effectiveness, he qualified as a diver and undertook numerous underwater operations using the limited equipment available at the time, including the Davis Submarine Escape Apparatus.
During one of a series of evaluation trials with Emily, the chariot unexpectedly dived to the seabed near the Detached Mole and was lost.

Around 1975, divers located a submerged chariot believed to be Emily resting at a depth of approximately 33 metres. Unfortunately, believing it still contained an unexploded warhead, naval clearance divers destroyed the vehicle. Subsequent examination indicated that this assessment had been incorrect, resulting in the loss of an important piece of Gibraltar's wartime heritage.

Further Reading

Those wishing to learn more about the Italian Chariot operations, the secret base aboard the Olterra, Lieutenant Lionel "Buster" Crabb, and Gibraltar's remarkable underwater wartime heritage are encouraged to read Underwater Gibraltar: A Guide to the Rock’s Submerged Sites, by Phil Smith and Darren Fa. The book provides a comprehensive account of the Rock's submerged archaeological sites, wartime wrecks and underwater military operations, and is highly recommended for anyone interested in Gibraltar's maritime history.Copies are available from the Gibraltar National Museum, and may also be purchased through selected booksellers and online retailers.