HMS L24 was a L-class submarine built for the Royal Navy during World War I. The boat was not completed before the end of the war and was sunk in an accidental collision in 1924.

Design and description

L9 and its successors were enlarged to accommodate 21-inch (53.3 cm) torpedoes and more fuel. The submarine had a length of 238 ft overall, a beam of 23 ft and a mean draft of 13 ft. They displaced 914 LT on the surface and 1089 LT submerged. The L-class submarines had a crew of 38 officers and ratings. They had a diving depth of 150 ft. For surface running, the boats were powered by two 12-cylinder Vickers 1200 bhp diesel engines, each driving one propeller shaft. When submerged each propeller was driven by a 600 hp electric motor. They could reach 17 kn on the surface and 10.5 kn underwater. On the surface, the L class had a range of 3800 nmi at 10 kn. The boats were armed with four 21-inch torpedo tubes in the bow and two 18-inch (45 cm) in broadside mounts. They carried four reload torpedoes for the 21-inch tubes for a grand total of ten torpedoes of all sizes. They were also armed with a 4 in deck gun.

Construction and career

HMS L24 was built by Vickers at their Barrow-in-Furness shipyard, launched on 19 February 1919, and completed at an unknown date. The boat was sunk with all hands lost in a collision with the battleship HMS Resolution (09) during an exercise off Portland Bill in the English Channel on 10 January 1924. A memorial is located in St Ann's Church in HMNB Portsmouth. The wreck is located at 50.375°N, -2.62983°W at a depth of 52 metres. Her hydroplanes remain set to hard dive, indicating that she was trying to take evasive action. A hatch is open and there is obvious damage where Resolution sliced into her hull. The wreck is designated as a protected place under the Protection of Military Remains Act 1986.