L9 and its successors were enlarged to accommodate 21-inch (53.3 cm) torpedoes and more fuel. The submarine had a length of 238feet overall, a beam of 23feet and a mean draft of 13feet.[1] They displaced 914LT on the surface and 1089LT submerged. The L-class submarines had a crew of 38 officers and ratings.[2] They had a diving depth of 150feet.
For surface running, the boats were powered by two 12-cylinder Vickers[3] 12000NaN0 diesel engines, each driving one propeller shaft. When submerged each propeller was driven by a 600hp electric motor.[1] They could reach 17kn on the surface and underwater. On the surface, the L class had a range of 3800nmi at .[4]
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.[5] They were also armed with a 4adj=onNaNadj=on deck gun.[2]
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 during an exercise off Portland Bill in the English Channel on 10 January 1924.[6] A memorial is located in St Ann's Church in HMNB Portsmouth.[7]
The wreck is located at 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.