Екінші дүниежүзілік соғыстағы британдық "X" кластық шағын суасты қайығы

Midget submarine class built for the Royal Navy during 1943–44

The X class was a World War II midget submarine class built for the Royal Navy during 1943–44. It was substantially larger than the original Chariot manned torpedo. Known individually as X Craft, the vessels were designed to be towed to their intended area of operations by a full size "mother" submarine – usually one of the T class or S class – with a passage crew on board, the operational crew being transferred from the towing submarine to the X Craft by dinghy when the operational area was reached, and the passage crew returning with the dinghy to the towing submarine. Once the attack was over, the X Craft would rendezvous with the towing submarine and then be towed home. Range was limited primarily by the endurance and determination of their crews, but was thought to be up to 14 days in the craft or , after suitable training. Actual range of the X Craft itself was surfaced and at submerged.

The craft was about 51 feet (16 m) long, 5.5 feet (2 m) maximum diameter and displaced surfaced and submerged. Propulsion was by a 4 cylinder Gardner 4LK X10 also penetrated the anchorage but was unable to attack and the crew were picked up by another submarine). Tirpitz was badly damaged, crippled, and out of action until May 1944; it was destroyed on 12 November 1944 by Avro Lancaster bombers during Operation Catechism in Tromsø, Norway. For this action, Cameron and Place were awarded the Victoria Cross, whilst Robert Aitken, Richard Haddon Kendall, and John Thornton Lorimer received the Distinguished Service Order and Edmund Goddard the Conspicuous Gallantry Medal. The commander of X8, John Elliott Smart, was appointed a Member of the Order of the British Empire (MBE). There was a possibility that X5 had also successfully planted explosive side charges before being destroyed, but this was never conclusively proven; its commander Henty Creer was not awarded a medal, but was mentioned in dispatches. X Craft were involved in the preparatory work for Overlord. Operation Postage Able was planned to take surveys of the landing beaches with X20, commanded by Lt KR Hudspeth, spending four days off the French coast. Periscope reconnaissance of the shoreline and echo soundings were performed during daytime. Each night, X20 would approach the beach and 2 divers would swim ashore. Soil samples were collected in condoms. The divers went ashore on two nights to survey the beaches at Vierville sur Mer, Moulins St Laurent and Colleville sur Mer in what became the American Omaha Beach. On the third night, they were due to go ashore off the Orne Estuary (Sword Beach), but by this stage fatigue (the crew and divers had been living on little more than benzedrine tablets) and the worsening weather caused Hudspeth to shorten the operation, returning to Dolphin on 21 January 1944. Hudspeth received a bar to his DSC. X20 and X23, each with a crew of five, acted as navigational beacons to help the D Day invasion fleet land on the correct beaches (Operation Gambit), as part of the Combined Operations Pilotage Parties (COPP). The craft were also equipped with a radio beacon and echo sounder to help direct Canadian and British ships to the suitable positions on Sword and Juno beaches. Oxygen bottles on both craft enabled the crews to remain submerged for extended periods during this operation, 64 hours of the 76 total hours at sea. Operations continued in the Far East with the revised XE class submarines.

X3 – unofficially named Piker 1, was lost on 4 November 1942 in Loch Striven due to a leaking engine valve. All crew escaped by utilizing their Davis Submerged Escape Apparatus. X5 – unofficially named Platypus, commanded by Lt. Henty Creer RNVR (also the operation's commander), crew S Lt. Nelson, Midshipman Malcolm, and ERA Mortiboys; passage crew Lt Terry Lloyd (commanding), L/S Element, Stoker Garrity. Henty Creer, Nelson, Malcolm, and Mortiboys were killed in the attack, though X5's exact fate is unknown. commanded by Lt. Basil C. G. Place, crew S Lt. R. Aitken, Lt. Whittam, and ERA Whitley; passage crew Lt Philip (commanding), Leading Seaman J. Magennis, Stoker Luck. X8 – unofficially named Expectant, commanded by Lt. McFarlane RAN commanded by Lt. EA Kearon RNVR; AH Harte (Able Seaman) and GH Hollet (Stoker). Foundered on 16 September 1942 while under tow from the Syrtis. X10 – unofficially named Excalibur, commanded by Lt. Hudspeth RANVR

This type of midget submarine was portrayed in the 1955 war film, Above Us the Waves, featuring John Mills, which was based on both Operation Source and the earlier Chariot attacks on the Tirpitz. An X class submarine – marked as "X2" – features in the 1959 film The Giant Behemoth (a. k. a. Behemoth the Sea Monster). This class of submarine was later featured in the 1968 movie Submarine X 1 starring James Caan as a Canadian Royal Naval Volunteer Reserve officer who after losing his submarine and fifty crew members in a battle with a German ship during World War II, gets a second chance training crews to take part in a raid using midget subs. A 1976 Douglas Reeman novel, Surface with Daring, features a fictionalized account of X class midget submarines, especially XE 16 and its crew, performing several highly secret operations in occupied Europe. A 2006 Alexander Fullerton novel, The Gatecrashers, features a fictionalized account of X class midget submarines, including X 12 piloted by one of the protagonists, that lays explosive charges to damage the Tirpitz.