SMS S31 (1913)

History
German Empire
Name	S31
Ordered	1913
Builder	Schichau-Werke, Elbing
Launched	20 December 1913
Commissioned	9 August 1914
Fate	Sunk by mine 19 August 1915
General characteristics
Displacement	971 tonnes (956 long tons)
Length	79.6 m (261 ft 2 in)
Beam	8.3 m (27 ft 3 in)
Draft	2.8 m (9 ft 2 in)
Installed power	23,500 shp (17,500 kW)
Propulsion	3 × water-tube boilers 2× Steam turbines 2 shafts
Speed	33.5 knots (62.0 km/h; 38.6 mph)
Range	1,100 nmi (2,000 km; 1,300 mi) at 20 knots (37 km/h; 23 mph)
Complement	83 officers and sailors
Armament	3 × 8.8 cm (3.5 in) SK L/45 guns 6 × 500 mm torpedo tubes 24 mines

SMS S31^[a][b] was a 1913 Type Large Torpedo Boat (Großes Torpedoboot ) of the Imperial German Navy. Commissioning in August 1914, she served during World War I and was sunk by a mine during the Battle of the Gulf of Riga on 19 August 1915.

In 1913, the Imperial German Navy placed orders for 12 high-seas torpedo boats, with a half-flotilla of six ordered from AG Vulcan (V25–V30) and Schichau-Werke (S31–S36). While the designs built by each shipyard were broadly similar, they differed from each other in detail, and were significantly larger and more capable than the small torpedo boats built for the German Navy in the last two years. S31 was the first of the six torpedo-boats ordered from the Schichau-Werke.^[2]

S31 was launched at Schichau's Elbing shipyard on 20 December 1913 and commissioned on 8 August 1914.^[3]

S31 was 79.6 metres (261 ft 2 in) long overall and 79.0 metres (259 ft 2 in) at the waterline, with a beam of 8.3 metres (27 ft 3 in) and a draft of 2.8 metres (9 ft 2 in).^[2] Displacement was 802 tonnes (789 long tons) normal and 971 tonnes (956 long tons) deep load.^[4] Three oil-fired water-tube boilers fed steam to 2 sets of Schichau steam turbines rated at 23,500 shaft horsepower (17,500 kW), giving a speed of 33.5 knots (62.0 km/h; 38.6 mph). 220 tonnes (220 long tons) of fuel oil was carried, giving a range of 1,100 nautical miles (2,000 km; 1,300 mi) at 20 knots (37 km/h; 23 mph).^[2]

Armament consisted of three 8.8 cm SK L/45 naval guns in single mounts, together with six 50 cm (19.7 in) torpedo tubes with two fixed single tubes forward and 2 twin mounts aft. Up to 24 mines could be carried.^[2][4] The ship had a complement of 83 officers and men.^[2]

In October 1914 S31 was a member of the 17th Half-Flotilla and took part in operations in the Baltic Sea.^[5] During August 1915 S31, as part of the 9th Torpedo Boat Flotilla, took part in the Battle of the Gulf of Riga. She struck a mine near the island of Ruhnu on 19 August, sinking with the loss of 11 men. The survivors were rescued by V184 and S35.^[3][6][7]

• Firle, Rudolph (1921). Der Krieg in der Ostsee: Erster Band: Von Kriegsbeginn bis Mitte März 1915. Der Krieg zur See: 1914–1918 (in German). Berlin: Verlag von E. S. Mittler und Sohn.
• Halpern, Pail G. (1994). A Naval History of World War I. London: UCL Press. ISBN 1-85728-498-4.
• Gardiner, Robert; Gray, Randal, eds. (1985). Conway's All The World's Fighting Ships 1906–1921. London: Conway Maritime Press. ISBN 0-85177-245-5.
• Gröner, Erich (1983). Die deutschen Kriegsschiffe 1815–1945: Band 2: Torpedoboote, Zerstörer, Schnelleboote, Minensuchboote, Minenräumboote. Koblenz, Germany: Bernard & Graefe Verlag. ISBN 3-7637-4801-6.
• Rollmann, Heinrich (1929). Der Krieg in der Ostsee: Zweiter Band: Das Kreigjahr 1915. Der Krieg zur See: 1914–1918 (in German). Berlin: Verlag von E. S. Mittler und Sohn.