History
United Kingdom
Name	HMSL23
Builder	Chatham Dockyard
Laid down	29 August 1917
Launched	1 July 1919
Commissioned	5 August 1924
Decommissioned	May 1946
Fate	Sank in tow to breakers May 1946
General characteristics
Class & type	L-class submarine
Displacement	914 long tons (929 t) surfaced 1,089 long tons (1,106 t) submerged
Length	238 ft 7 in (72.7 m)
Beam	23 ft 6 in (7.2 m)
Draught	13 ft 3 in (4.0 m)
Installed power	2,400 bhp (1,800 kW) (diesel) 1,600 hp (1,200 kW) (electric)
Propulsion	2 ×diesel engines 2 ×electric motors
Speed	17 kn (31 km/h; 20 mph) surfaced 10.5 kn (19.4 km/h; 12.1 mph) submerged
Range	3,800 nmi (7,000 km; 4,400 mi) at 10 kn (19 km/h; 12 mph) on the surface
Test depth	150 feet (45.7 m)
Complement	38
Armament	4 × bow21 in (533 mm)torpedo tubes 2 × beam18 in (457 mm) torpedo tubes 1 ×4-inchdeck gun

HMSL23 was aL-class submarine built for the Royal Navy during World War I. The boat was not completed before the end of the war and was one of the three L-class boats to serve during World War II.L23 was sold forscrap in 1946, but sank in tow in May 1946.

L9 and its successors were enlarged to accommodate21-inch (53.3 cm) torpedoes and more fuel. The submarine had a length of 238 feet 7 inches (72.7 m)overall, abeam of 23 feet 6 inches (7.2 m) and a meandraft of 13 feet 3 inches (4.0 m).^[1] Theydisplaced 914 long tons (929 t) on the surface and 1,089 long tons (1,106 t) submerged. The L-class submarines had a crew of 35 officers andratings.^[2] They had a diving depth of 150 feet (45.7 m).^[3]

For surface running, the boats were powered by two 12-cylinderVickers^[4] 1,200-brake-horsepower (895 kW)diesel engines, each driving onepropeller shaft. When submerged each propeller was driven by a 600-horsepower (447 kW)electric motor.^[1] They could reach 17knots (31 km/h; 20 mph) on the surface and 10.5 knots (19.4 km/h; 12.1 mph) underwater. On the surface, the L class had a range of 3,800nautical miles (7,000 km; 4,400 mi) at 10 knots (19 km/h; 12 mph).^[3]

The boats were armed with four 21-inchtorpedo tubes in the bow and two18-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 4-inch (102 mm)deck gun.^[2]

HMSL23 waslaid down on 26 July 1917 byVickers at theirBarrow-in-Furnessshipyard,launched on 1 July 1919. The boat was then towed toChatham Royal Dockyard and finished on 31 October 1924. She served on the China Station in the 1920s. HMSL23 survived a heavydepth charge attack by twoGermandestroyers in February 1940. An oil leak occurred, which lead the Germans to believe that the submarine was destroyed.L23 was sold for scrap in May 1946.

• Akermann, Paul (2002).Encyclopaedia of British Submarines 1901–1955 (reprint of the 1989 ed.). Penzance, Cornwall: Periscope Publishing.ISBN 1-904381-05-7.
• Colledge, J. J.; Warlow, Ben (2006) [1969].Ships of the Royal Navy: The Complete Record of All Fighting Ships of the Royal Navy from the 15th Century to the Present (Rev. ed.). London: Chatham Publishing.ISBN 978-1-86176-281-8.OCLC 67375475.
• Gardiner, Robert & Gray, Randal, eds. (1985).Conway's All the World's Fighting Ships 1906–1921. Annapolis, Maryland: Naval Institute Press.ISBN 0-85177-245-5.
• Harrison, A. N. (January 1979)."The Development of HM Submarines From Holland No. 1 (1901) to Porpoise (1930) (BR3043)". RN Subs. Retrieved27 September 2022.

• British L-class submarines
• Ships built in Barrow-in-Furness
• 1919 ships
• World War I submarines of the United Kingdom
• Royal Navy ship names

• Use dmy dates from December 2016
• Use British English from December 2016
• All Wikipedia articles written in British English
• Ship infoboxes without an image