HMS L18


HMS L9 was a L-class submarine built for the Royal Navy during World War I. The boat was completed after the war and was sold for scrap in 1936.

Design and description

L9 and its successors were enlarged to accommodate 21-inch torpedoes and more fuel. The submarine had a length of overall, a beam of and a mean draft of. They displaced on the surface and submerged. The L-class submarines had a crew of 38 officers and ratings.
For surface running, the boats were powered by two 12-cylinder Vickers diesel engines, each driving one propeller shaft. When submerged each propeller was driven by a electric motor. They could reach on the surface and underwater. On the surface, the L class had a range of at.
The boats were armed with four 21-inch torpedo tubes in the bow and two 18-inch 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 deck gun.

Construction and career

HMS L18 was laid down on 22 June 1917 by Vickers at their Barrow-in-Furness shipyard, launched on 21 November 1918, and completed on 15 May 1919. In February 1927, L18 trained with the submarines and her sister. The boat was sold in October 1936 at Pembroke Dock.