HMS C11

HMS C38 – a typical C-class submarine
History
United Kingdom
Name	HMS C11
Builder	Vickers, Barrow
Laid down	6 April 1906
Launched	27 March 1907
Commissioned	3 September 1907
Fate	Sunk in collision 14 July 1909
General characteristics
Class and type	C-class submarine
Displacement	287 long tons (292 t) surfaced 316 long tons (321 t) submerged
Length	142 ft 3 in (43.4 m)
Beam	13 ft 7 in (4.1 m)
Draught	11 ft 6 in (3.5 m)
Installed power	600 bhp (450 kW) petrol 300 hp (220 kW) electric
Propulsion	1 × 16-cylinder Vickers petrol engine 1 × electric motor
Speed	12 kn (22 km/h; 14 mph) surfaced 7 kn (13 km/h; 8.1 mph) submerged
Range	910 nmi (1,690 km; 1,050 mi) at 12 kn (22 km/h; 14 mph) on the surface
Test depth	100 feet (30.5 m)
Complement	2 officers and 14 ratings
Armament	2 × 18 in (450 mm) bow torpedo tubes

HMS C11 was one of 38 C-class submarines built for the Royal Navy in the first decade of the 20th century. The boat was lost after being rammed in 1909.

The C class was essentially a repeat of the preceding B class, albeit with better performance underwater. The submarine had a length of 142 feet 3 inches (43.4 m) overall, a beam of 13 feet 7 inches (4.1 m) and a mean draft of 11 feet 6 inches (3.5 m). They displaced 287 long tons (292 t) on the surface and 316 long tons (321 t) submerged. The C-class submarines had a crew of two officers and fourteen ratings.^[1]

For surface running, the boats were powered by a single 16-cylinder 600-brake-horsepower (447 kW) Vickers petrol engine that drove one propeller shaft. When submerged the propeller was driven by a 300-horsepower (224 kW) electric motor.^[1] They could reach 12 knots (22 km/h; 14 mph) on the surface and 7 knots (13 km/h; 8.1 mph) underwater. On the surface, the C class had a range of 910 nautical miles (1,690 km; 1,050 mi) at 12 knots (22 km/h; 14 mph).^[2]

The boats were armed with two 18-inch (45 cm) torpedo tubes in the bow. They could carry a pair of reload torpedoes, but generally did not as they would have to remove an equal weight of fuel in compensation.^[3]

C11 was built by Vickers at their Barrow-in-Furness shipyard, laid down on 6 April 1906 and was commissioned on 3 September 1907. The boat was sunk in a collision with the collier Eddystone in the North Sea south of Cromer, Norfolk on 14 July 1909.^[4] There were only three survivors.^[4] Attempts were made to salvage the stricken submarine but they were abandoned in September 1909, after only a single body had been recovered.^[5] The wreck was rediscovered in the late 1990s.

• 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 (Rev. ed.). London: Chatham Publishing. ISBN 978-1-86176-281-8.
• 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. Retrieved 27 September 2022.

• HMS C11 Roll of Honour
• 'Submarine losses 1904 to present day' – Royal Navy Submarine Museum Archived 7 January 2018 at the Wayback Machine