HMS Sterlet (2S)

The second batch of S-class submarines were designed as slightly improved and enlarged versions of the earlier boats of the class and were intended to operate in the North and Baltic Seas.[1] The submarines had a length of 208 feet 8 inches (63.6 m) overall, a beam of 24 feet (7.3 m) and a mean draught of 11 feet 10 inches (3.6 m). They displaced 768 long tons (780 t) on the surface and 960 long tons (980 t) submerged.[2] The S-class submarines had a crew of 40 officers and ratings. They had a diving depth of 300 feet (91.4 m).[3]

For surface running, the boats were powered by two 775-brake-horsepower (578 kW) diesel engines, each driving one propeller shaft. When submerged each propeller was driven by a 650-horsepower (485 kW) electric motor. They could reach 13.75 knots (25.47 km/h; 15.82 mph) on the surface and 10 knots (19 km/h; 12 mph) underwater.[4] On the surface, the second-batch boats had a range of 6,000 nautical miles (11,000 km; 6,900 mi) at 10 knots (19 km/h; 12 mph) and 64 nmi (119 km; 74 mi) at 2 knots (3.7 km/h; 2.3 mph) submerged.[3]

The S-class boats were armed with six 21-inch (533 mm) torpedo tubes in the bow. They carried six reload torpedoes for a total of a dozen torpedoes. They were also armed with a 3-inch (76 mm) deck gun.[2]

Ordered on 2 March 1936, Sterlet was laid down on 14 July 1936 in HM Dockyard, Chatham and was launched on 22 September 1936. The boat was completed on 6 April 1938.[5]

At the onset of the Second World War, Sterlet was a member of the 2nd Submarine Flotilla. From 23–26 August 1939 the 2nd Submarine Flotilla transferred to its war bases at Dundee and Blyth.[6]

On 8 April 1940 Sterlet left for a patrol in the Skagerrak, off Norway under the command of Lt. Gerard Henry Stacpoole Haward. Four days later she unsuccessfully attacked a convoy of three merchant ships and a destroyer. The following day she was assigned a new patrol area and on 14 April torpedoed the German gunnery training ship Brummer, leading to her sinking the following day.[7]

She was possibly sunk by the German anti submarine trawlers UJ-125, UJ-126 and UJ-128 on 18 April. Alternatively, she may have struck a mine whilst returning to port.[8]

• Akermann, Paul (2002). Encyclopaedia of British Submarines 1901–1955 (reprint of the 1989 ed.). Penzance, Cornwall: Periscope Publishing. ISBN 1-904381-05-7.
• Bagnasco, Erminio (1977). Submarines of World War Two. Annapolis, Maryland: Naval Institute Press. ISBN 0-87021-962-6.
• 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.
• Chesneau, Roger, ed. (1980). Conway's All the World's Fighting Ships 1922–1946. Greenwich, UK: Conway Maritime Press. ISBN 0-85177-146-7.
• Harrison, A. N. (January 1979). "The Development of HM Submarines From Holland No. 1 (1901) to Porpoise (1930) (BR3043)". Submariners Association: Barrow in Furness Branch. Archived from the original on 19 May 2015. Retrieved 19 August 2015.
• McCartney, Innes (2006). British Submarines 1939–1945. New Vanguard. 129. Oxford, UK: Osprey. ISBN 1-84603-007-2.
• Rohwer, Jürgen (2005). Chronology of the War at Sea 1939–1945: The Naval History of World War Two (Revised & Expanded ed.). Annapolis, Maryland: Naval Institute Press. ISBN 1-59114-119-2.