X-Craft file photo [29102]

X-class Midget Submarine

CountryUnited Kingdom
Displacement27 tons standard; 30 tons full
Length51 feet
Beam6 feet
Draft5 feet
MachineryOne Gardner 4cyl Diesel engine, one Blackman electric motor
Power Output42 shaft horsepower
Speed6 knots
Range1,200 miles
ArmamentTwo large detachable explosive charges
Submerged Speed5 knots submerged


This article refers to the entire X-class; it is not about an individual vessel.

ww2dbaseRenowned ex-submariner Admiral Sir Max Horton provided the inspiration for the X-Craft midget submarines, but development work led by Commander (Retired) Cromwell Hanford Varley, D.S.C. proceeded somewhat slowly until there arose the strategic need to develop a means of striking at German heavy surface units located in Norwegian fjords. Following successful prototype trials during 1942 the Admiralty ordered the building of six boats (designated X5-X10).

ww2dbaseX-Craft were about fifty-one feet long, a one-compartment midget submarine weighing some thirty-five tons with no pretence of comfort for the crew of four who were squeezed into a cramped cabin that was only five feet eight inches high, five feet wide and barely eight feet long. Hot and stuffy the cabin had hardly room for the crew to stand up or sit down. The crew usually consisted of three officers and an engine room artificer. They were all volunteers who received special training in diving and the arcane techniques of penetrating booms and net defences. With a theoretically range of 1,200 miles possible at four knots, the crew (it was hoped) might be expected to stay at sea for at least ten days although, in practice, they were usually towed on the surface by a parent submarine with a passage crew before switching to an operational crew for the attack.

ww2dbaseA little vessel with a mighty punch, these midget submarines could make six and a half knots on the surface, could dive to 300 feet and propel themselves at five knots when submerged. The weapon of the X-Craft submarine was not the torpedo but a pair of large neutrally buoyant explosive charges, containing four tons (4,400 pounds each) of amatol strapped to the sides of the hull, which could be jettisoned from the interior beneath the intended target on a time–delay fuse. No forward hydroplanes were installed and control at low speed was often hit and miss. A second improved group (designated XE–craft) were built later in the war to replace losses.

ww2dbaseOn 11 Sep 1943, the six X-Craft set out from their depot ship HMS Bonaventure (F139)1 in Loch Cairnbawn, Scotland, United Kingdom on Operation Source with the intention of delivering a knock-out blow on one of the Royal Navy's most feared opponent, battleship Tirpitz, which had just returned to her safe haven after a successful raid on Spitsbergen, Norway. For most of their ten day journey across the North Sea, the X-Craft were towed by conventional submarines. Three of them were lost on the way. X8 (Lieutenant B. M. McFarlane RAN) had to be scuttled because of mechanical defects. X9 (Sub-Lieutenant E. W. Kearon RNVR) was lost with all hands on passage. X10 (Lieutenant Ken Hudspeth RANVR) which had intended to attack the battlecruiser Scharnhorst, thought to be in a fjord, was also beset with mechanical problems, finally abandoned the mission and limped back home. Despite this setback the three remaining X-Craft homed in on the Tirpitz, anchored in Altenfjord. At 0200 hours Lieutenant Donald Cameron RNR in X6 approached the Tirpitz but was stopped by a torpedo net. Taking a gamble Cameron came to the surface to pass through a gap in the wake of a small coaster. They were spotted, by look-outs on Tirpitz who thought X6 to be a porpoise and did not open fire.

ww2dbaseTo make matters worse X6's periscope stopped working. Lieutenant Cameron was forced to proceed blindly. He came to the surface again but this time they came under fire from the Tirpitz (although they were now so close that the battleship could not use her bigger guns). Cameron decided to lay his explosive charges as close as he could and then scuttle his midget submarine. Setting the time fuses and releasing the charges the crew of X6 indicated that they wished to surrender and were duly taken as prisoners aboard the German warship.

ww2dbaseIt now fell to Lieutenant B. C. Godfrey Place RN in X7 to strike at the Tirpitz. Members of the crew, using diving gear, cut their way through the anti-submarine nets allowing their X-Craft to reach their target. Proceeding, undetected, he managed to release one charge directly beneath the battleship's forward turrets and the second under her stern turrets, before making a rapid bid to escape back through the hole in the defensive net that they had broken through. At 0812 hours the charges detonated causing serious damage to the German battleship's main turbines and fire control. Unfortunately, the shock wave jolted X7 to the surface where it became entangled and damaged on the net. Place and one crewman managed to get clear but his two other crewmen were trapped inside and sank with the boat. Although most of the crew of the X7 and X6 had survived the mission, the third craft, Lieutenant H. Henry-Creer's X5 had mysteriously disappeared with all hands. The damage to the Tirpitz would take the Germans six months to repair. Both Lieutenants Place and Cameron would eventually be awarded the Victoria Cross. This action was immortalised in the 1955 film "Above us the waves".

ww2dbaseThe X-Craft boats lost during the attack on the Tirpitz would be replaced early in 1944 with six new boats, designated X20 to X25 (plus six more for training purposes). In Norway on 15 Apr 1944, X24 2 penetrated Bergen harbour to attack the Laksevåg floating dock in Puddefjord. Although X24 did manage to plant the explosive charges these only managed to sink the large freighter Bärenfels and did little damage to the actual dock. On 11 Sep 1944, the attack (Operation Heckle) was repeated when Lieutenant H. P. Westmacott RN took X24 back again to finally succeed in sinking the dock.

ww2dbaseTwo X-Craft would play a vital role in the Normandy, France landings in Jun 1944. X23 (Lieutenant George Honour RNVR) and, twenty miles away, X20 (Lieutenant Hudspeth) were tasked to mark both ends of the British and Canadian invasion beaches, Sword, Juno and Gold. Their mission was to set up a mast with a flashing light plus a radio beacon and echo sounder to aid the invasion fleet to home in on the correct landing beaches. They left Portsmouth, England, United Kingdom with crews of five (which included two navigation experts) on 2 Jun 1944 and sailed across the channel to submerge off the Normandy coast. Then, from dawn on 4 Jun 1944, they used village church steeples to position themselves ready to guide in the invasion fleet. On 5 Jun 1944 a message was received notifying that the invasion had been postponed for 24 hours because of bad weather. They submerged to the seabed to sit out the delay. When they resurfaced on 6 Jun 1944 the submariners finally got the go-ahead to commence their important mission. At the end of that first day of the invasion, and with Allied troops already beginning to move off the beaches, the exhausted crews of the two X-Craft, their task completed, could head out to the transport area in search of their tow-ships for the trip back home.

ww2dbaseThe midget submarines would also participate in missions on the far side of the world. The depot ship HMS Bonaventure (Captain "Tiny" Fell RN) arrived at Victoria harbour, Crown Colony of Labuan, in Jul 1945 with six XE-craft and their crews. Although at first it seemed that no operational use would be found for them, these craft actually distinguished themselves in several memorable exploits before the war ended; XE4 (Lieutenant Max Shean RANVR) cut submarine telegraph cable at Cape St Jacques, Saigon, Cochinchina, French Indochina on 31 Jul 1944, and XE5 (Lieutenant Herbert Westmacott RN) did the same in Lamma Channel, off Hong Kong, on 1 Aug 1944. Meanwhile XE1 (Lieutenant "Jack" Smart RNVR) and XE3 (Lieutenant Ian Fraser RNR) would attack shipping in Singapore harbour.

ww2dbaseXE1 and XE3 departed Brunei Bay near Labuan on 31 Jul 1944, towed by the submarines HMS Spark and HMS Stygian respectively. XE3's target was the 9,850-ton Japanese cruiser Takao, at present lying in the Jahore Straits after being damaged in Oct 1944 by US Submarine Darter during the Battle of Leyte Gulf. In the strait where the cruiser was moored the water is shallow, with depths of from eleven to seventeen feet which dropped to under three feet at low tide. But there was a depression in the seabed here which amounts to a hole, 500 feet across, 1,500 feet long and a little over five feet deeper than the surrounding sea bed. The Takao lay across this depression so that a hundred feet of her length at the bow and stern lay on the shallower patch and the rest of her keel over the hole. It was planned that XE3, (manned by Lieutenant Ian Fraser, Sub-Lieutenant William J. L. Smith RNZNVR, Engine Room Artificer Charles Reid and Belfast-born diver Leading Seaman J. Joseph "Mick" Magennis) should pass over the shallow patch and descend into the hole beneath the cruiser where Magennis would attach limpet mines under the enemy vessel.

ww2dbaseAt 0208 hours Lieutenant Fraser commenced the attack from 2,000 yards but his course took them too far forward of the target and they almost ran into a Japanese liberty boat full of sailors going ashore. At 0303 hours he tried again with more success; the submarine sliding down the hole under the Takao. Magennis, the diver, exited through the diving chamber, collected six limpet mines and began the difficult task of attaching them to the cruiser. After thirty minutes he returned and Fraser prepared to commence their escape. The final task before departing would be to drop the explosive charges on either side of the submarine but, unfortunately, only the port-side charge fell away cleanly. Magennis, although exhausted from his earlier exertions, volunteered to go outside again and, equipped with a very large spanner managed to prise the starboard charge free. The delay now presented a more serious problem. As the tide went down the weight of the cruiser nearly crushed the midget. Magennis had to make several underwater attempts to free the submarine before XE3 could, at last, begin its way back to the Stygian.

ww2dbaseXE1's target was to have been the cruiser Myoko lying some two miles further up the straits. But XE1 became delayed by Japanese patrol boats and, with time running out, added her charges to XE3's burden under the Takao.

ww2dbaseThe resultant explosions would blow a 66-foot by 33-foot wide hole in the Takao which flooded several compartments below the lower deck; including two (empty) ammunition magazines, the main gun plotting room and the lower communication room. The damage was so significant that the Takao would never again be able to play a part in the war. Both XE-craft returned safely to Brunei Bay on 4 Aug 1944. Both Lieutenant Fraser and Leading Seaman Magennis would ultimately be awarded the Victoria Cross 3 for their gallantry during this operation.

ww2dbaseXE8 is now an exhibit at the Chatham Historic Dockyard.

1. Not to be confused with the Dido-Class Light Cruiser HMS Bonaventure sunk in 1941
2. X24 is now an exhibit at the Royal Navy Submarine Museum at Gosport.
3. In 1986 Lord Ashcroft, the former deputy chairman of the Conservative Party, paid £29,000 at a Sotherby's sale for the Victoria Cross awarded to Leading Seaman Magennis. Since then, Ashcroft's collection of Victoria Crosses now numbers 213, the largest in the world, and is on public display at the Imperial War Museum.

Bernard Ireland: Warships of World War II (Collins/Janes, 1996)
Peter Marriot: Midget Submarines at War (Military Illustrated, Sept 2007)
John Winton: The War at Sea (Book Club Associates 1974)
Cornelius Ryan: The Longest Day (New English Library Edition, 1982)
Kim Lockwood: D-Day Landings - 70th Anniversary Edition (Wilkinson Publishing, 2014)
Medals of Honour (Lincolnshire Echo, 25 April 2019)

Last Major Revision: Oct 2019


X-Craft underway, 1943-1944

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Visitor Submitted Comments

1. Anonymous says:
8 Jun 2021 12:10:48 PM

Did the x craft on D day carry external bombs?

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