Britain's commando frogman force is now the Special Boat Service (SBS), whose members are drawn largely from the Royal Marines. They perform various operations on land as well as in the water. Until the late 1990s, all members of the Special Air Service (SAS) Boat Troop were trained as commando frogmen.
In 1909 the British designer Commander Godfrey Herbert received a patent for a manned torpedo. During World War I, it was rejected by the War Office as impracticable and unsafe. Instead, in the inter-war period the Italian Navy successfully trained the special frogmen corps Decima Flottiglia MAS equipped with a new and powerful craft: a slow speed human torpedo (SLC: siluro a lenta corsa, best known as maiale). Italian manned torpedoes were first used against Britain in 1941 when Italian commando frogmen, some riding manned torpedoes, attacked British naval bases at Malta, Gibraltar and Alexandria. In the last operation six Italian frogmen rode three SLC's into the harbour and damaged the British battleships Queen Elizabeth and Valiant, and the tanker Sagona (the six frogmen were then captured). After these operations had shown how powerful and effective this weapon was the Royal Navy was convinced to create their own programme. This was also fictionalised in the 1958 film The Silent Enemy .
By the end of the war, the British human torpedo operations had earned their participants 20 medals and 16 men had been killed.
Clearance Diving Teams were formed to clear unexploded ordnance and other military hazards left over from the war.
A frogman is someone who is trained in scuba diving or swimming underwater in a tactical capacity that includes military, and in some European countries, police work. Such personnel are also known by the more formal names of combat diver, combatant diver, or combat swimmer. The word frogman first arose in the stage name the "Fearless Frogman" of Paul Boyton in the 1870s and later was claimed by John Spence, an enlisted member of the U.S. Navy and member of the OSS Maritime Unit, to have been applied to him while he was training in a green waterproof suit.
A midget submarine is any submarine under 150 tons, typically operated by a crew of one or two but sometimes up to six or nine, with little or no on-board living accommodation. They normally work with mother ships, from which they are launched and recovered and which provide living accommodation for the crew and support staff.
HMS Sceptre (P215) was a third-batch S-class submarine built for the Royal Navy during World War II. Completed in April 1943, she spent the majority of her career in the North Sea, off Norway. After an uneventful patrol, the submarine participated in Operation Source, an attack on German battleships in Norway using small midget submarines to penetrate their anchorages and place explosive charges. However, the midget submarine that she was assigned to tow experienced technical difficulties and the mission was aborted. During her next four patrols, Sceptre attacked several ships, but only succeeded in severely damaging one. She was then ordered to tow the submarine X24, which was to attack a floating dry dock in Bergen. The operation, codenamed Guidance, encountered difficulties with the attacking submarine's charts, and the explosives were laid on a merchant ship close to the dock instead. The dock was damaged and the ship sunk, and X24 was towed back to England. Sceptre then conducted a patrol in the Bay of Biscay, sinking two German merchant ships, before being reassigned to tow X24 to Bergen again. The operation was a success, and the dry dock was sunk.
Human torpedoes or manned torpedoes are a type of diver propulsion vehicle on which the diver rides, generally in a seated position behind a fairing. They were used as secret naval weapons in World War II. The basic concept is still in use.
The Shetland Bus was the nickname of a clandestine special operations group that made a permanent link between Mainland Shetland in Scotland and German-occupied Norway from 1941 until the surrender of Nazi Germany on 8 May 1945. This link transferred agents in and out of Norway and provided them with weapons, radios and other supplies. From mid-1942, the group's official name was the Norwegian Naval Independent Unit (NNIU). In October 1943, it became an official part of the Royal Norwegian Navy and was renamed the Royal Norwegian Naval Special Unit (RNNSU). The unit was operated initially by a large number of small fishing boats and later augmented by three fast and well-armed submarine chasers – Vigra, Hessa and Hitra.
The Decima Flottiglia MAS was an Italian flotilla, with marines and commando frogman unit, of the Regia Marina. The acronym MAS also refers to various light torpedo boats used by the Regia Marina during World War I and World War II.
HMS P311 was a T-class submarine of the Royal Navy, the only boat of her class never to be given a name. She was to have received the name Tutankhamen but was lost before this was formally done. P311 was a Group 3 T-class boat built by Vickers-Armstrong at Barrow-in-Furness and commissioned on 5 March 1942 under the command of Lieutenant R.D. Cayley. She was one of only two T-class submarines completed without an Oerlikon 20 mm anti-aircraft gun, the other being HMS Trespasser.
The Welman submarine was a Second World War one-man British midget submarine developed by the Special Operations Executive. It only saw action once and was not particularly successful.
HMS Safari was a third batch S-class submarine built for the Royal Navy during World War II. Commissioned in 1942, she was assigned to operate in the Mediterranean Sea. During the course of the war, Safari sank twenty-five ships, most of which were Italian.
Above Us the Waves is a 1955 British war film about human torpedo and midget submarine attacks in Norwegian fjords against the German battleship Tirpitz. Directed by Ralph Thomas, it is based on two true-life attacks by British commando frogmen, first using Chariot manned torpedoes in Operation Title in 1942, and then X-Craft midget submarines in Operation Source in 1943. Filmed at Pinewood Studios, England, with outdoor scenes in Guernsey, some of the original war equipment was used in the film.
Teseo Tesei was an Italian naval officer, who invented the human torpedo used by the Regia Marina during World War II.
HMS Sickle was a third-batch S-class submarine built for the Royal Navy during World War II. Completed in 1942, she made her initial war patrol off the Norwegian coast. Sickle then sailed to Gibraltar, from where she conducted one patrol, then to Algiers, French North Africa. From 10 May to 10 October, the boat patrolled the Gulf of Genoa five times and sank a German submarine as well as three minesweepers and an escort ship. She then moved to Beirut, French Lebanon, and conducted two patrols in the Aegean Sea, sinking three caïques and a merchant ship, in addition to landing resistance operatives in Greece.
HMS Saracen was a third-batch S-class submarine built for the Royal Navy during the Second World War. Completed in 1942, Saracen conducted a patrol in the North Sea where she sank a German U-boat. She was then assigned to the 10th Submarine Flotilla in Malta, from where she made three patrols; on her second, she sank an Italian submarine. Saracen was then reassigned to the 8th Submarine Flotilla, based in Algiers, French North Africa.
HMS Sahib was a third-batch S-class submarine built for the Royal Navy during the Second World War. She was launched on 19 January 1942 and commissioned on 13 May 1942. She was the only British naval vessel to bear the name Sahib.
HMS Sportsman was a third-batch S-class submarine built for the Royal Navy during World War II. Completed in 1942, she spent most of the war serving in the Mediterranean Sea. After an initial patrol off Norway, she sank the heavy transport Général Bonaparte in the Mediterranean in 1943 and missed a French oil tanker. She was heavily damaged after a mistaken attack by an Allied bomber, and was sent east after repairs to participate in operations in the Black Sea. After the operation was cancelled, Sportsman patrolled the Aegean Sea, sending several Greek and German ships to the bottom. She sank the German transport SS Petrella in early 1944 despite it being clearly marked as a prisoner-of-war ship, killing 2,670 out of 3,173 Italians aboard. Sportsman sank several more ships, and suffered minor damage when she was detected and sighted while attempting to attack a convoy.
Vice-Admiral Sir Arthur Richard Hezlet, nicknamed Baldy Hezlet, was a decorated Royal Navy submariner. He became the Royal Navy's youngest captain at the time – aged 36 – and its youngest admiral, aged 45. In retirement he became a military historian.
The Raid on Alexandria was carried out on 19 December 1941 by Italian Navy divers of the Decima Flottiglia MAS, who attacked and sank two Royal Navy battleships at their moorings and damaged an oil tanker and a destroyer in the harbour of Alexandria, Egypt, using manned torpedoes.
The Raid on Algiers took place on 11 December 1942, in the Algiers harbour. Italian manned torpedoes and commando frogmen from the Decima Flottiglia MAS were brought to Algiers aboard the Perla-class submarine Ambra. The participating commandos were captured after setting limpet mines which sank two Allied ships and damaged two more.
The Chariot was a British manned torpedo used in World War II. The Chariot was inspired by the operations of Italian naval commandos, in particular the raid on 19 December 1941 by members of the Decima Flottiglia MAS who rode "Maiali" manned torpedoes into the port of Alexandria and there placed limpet mines on or near the battleships HMS Valiant and HMS Queen Elizabeth as well as an 8,000-ton tanker, causing serious damage which put both battleships out of operational use until 1943.
Operation Title was an unsuccessful Allied attack on the German battleship Tirpitz during the Battle of the Atlantic in World War II. It involved two British Chariot manned torpedoes that were transported close to the battleship's anchorage in Trondheimsfjorden in occupied Norway, by a Norwegian-crewed boat between 26 and 31 October 1942. The attack was abandoned following the accidental loss of both Chariots during the evening of 31 October.