SM U-18 (second row, second from the right)
Career (Germany)
Name:	U-18
Ordered:	May 6, 1910
Builder:	Kaiserliche Werft Danzig
Cost:	2,333,000 Goldmark
Laid down:	27 October 1910
Launched:	25 April 1912
Commissioned:	17 November 1912
General characteristics
Class and type:	German Type U 17 submarine
Displacement:	564 t (622 short tons) surfaced 691 t (762 short tons) submerged
Length:	62.35 m (204 ft 7 in)
Beam:	6 m (19 ft 8 in)
Height:	7.30 m (23 ft 11 in)
Draught:	3.40 m (11 ft 2 in)
Propulsion:	2 shafts 2 × 2 Körting 8-cylinder two stroke paraffin motors with 1,400 PS (1,400 hp) 2 × AEG electric motors with 1,120 PS (1,100 hp) 550 rpm surfaced 425 rpm submerged
Speed:	14.9 knots (27.6 km/h; 17.1 mph) surfaced 9.5 knots (17.6 km/h; 10.9 mph) submerged
Range:	6,700 nautical miles (7,700 mi; 12,400 km) at 8 kn surfaced 75 nautical miles (86 mi; 139 km) at 5 kn submerged
Test depth:	50 m (164 ft 1 in)
Boats and landing craft carried:	1 dingi
Complement:	4 officers, 25 men
Armament:	4 x 45 cm (17.7 in) torpedo tubes (2 each bow and stern) with 6 torpedoes
Service record
Part of:	German Imperial Navy: II Flotilla 1 Aug 1914 – 23 Nov 1914
Commanders:	Kptlt Heinrich von Henning[1] 1 Aug 1914 – 23 Nov 1914
Operations:	3 patrols
Victories:	None

SM U-18 was one of 329 submarines serving in the Imperial German Navy in World War I. U-18 engaged in the commerce warfare in the First Battle of the Atlantic.

Launched in October 1914, she was commanded by Kaptlt. von Hennig.^[2]

On her third mission, on 23 November U-18 penetrated the fleet anchorage of Scapa Flow via Hoxa Sound, following a steamer through the boom and entering the anchorage with little difficulty. However, the fleet was absent, being dispersed in anchorages on the west coast of Scotland and Ireland. As U-18 was making her way back out through Hoxa Sound to the open sea, her periscope was spotted by a guard boat. The trawler Dorothy Gray altered course and rammed the periscope, rendering it unserviceable. U-18 then suffered a failure of her diving plane motor and the boat became unable to maintain her depth, at one point even impacting the seabed. She was rammed a second time by the Dorothy Gray and eventually, her captain was forced to surface and scuttle his command just outside the Hoxa Gate, and all crew members, except one, were picked up by British boats.^[3][4] 58°41′N 02°55′W / 58.683°N 2.917°W / 58.683; -2.917. One man died and 22 were captured.^[5]

The wreck lies 75 m (246 ft) below the surface just outside the Hoxa Gate, at 58°41′N 02°55′W / 58.683°N 2.917°W / 58.683; -2.917Coordinates: 58°41′N 02°55′W / 58.683°N 2.917°W / 58.683; -2.917.^[6]

Notes[edit]

References[edit]

• Spindler, Arno (1932,1933,1934,1941/1964,1966). Der Handelskrieg mit U-Booten. 5 Vols. Berlin: Mittler & Sohn. Vols. 4+5, dealing with 1917+18, are very hard to find: Guildhall Library, London, has them all, also Vol. 1-3 in an English translation: The submarine war against commerce.  Check date values in: |date= (help)
• Beesly, Patrick (1982). Room 40: British Naval Intelligence 1914-1918. London: H Hamilton. ISBN 978-0241108642. 
• Halpern, Paul G. (1918). A Naval History of World War I. New York: Routledge. ISBN 978-1857284980. 
• Roessler, Eberhard (1997). Die Unterseeboote der Kaiserlichen Marine. Bonn: Bernard & Graefe. ISBN 978-3763759637. 
• Schroeder, Joachim (2002). Die U-Boote des Kaisers. Bonn: Bernard & Graefe. ISBN 978-3763762354. 
• Koerver, Hans Joachim (2008). Room 40: German Naval Warfare 1914-1918. Vol I., The Fleet in Action. Steinbach: LIS Reinisch. ISBN 978-3-902433-76-3. 
• Koerver, Hans Joachim (2009). Room 40: German Naval Warfare 1914-1918. Vol II., The Fleet in Being. Steinbach: LIS Reinisch. ISBN 978-3-902433-77-0. 

External links[edit]

• Uboat.net: More detailed information about U-18.
• Room 40: original documents, photos and maps about World War I German submarine warfare and British Room 40 Intelligence from The National Archives, Kew, Richmond, UK.