U-9 ready for patrol.
|Ordered:||15 July 1908|
|Builder:||Kaiserliche Werft, Danzig|
|Launched:||22 February 1910|
|Commissioned:||18 April 1910|
|Fate:||Surrendered 26 November 1918. Broken up at Morecambe in 1919.|
|Class and type:||German Type U 9 submarine|
|Height:||7.05 m (23.1 ft)|
|Draught:||3.13 m (10 ft 3 in)|
|Test depth:||50 m (160 ft)|
|Boats & landing
|Complement:||4 officers, 25 enlisted|
U-9 had an overall length of 57.38 m (188 ft 3 in), her pressure hull was 48 m (157 ft 6 in) long. The boat's beam was 6 m (19 ft 8 in) (o/a), while the pressure hull measured 3.65 m (12 ft 0 in). She had a draught of 3.13 m (10 ft 3 in) with a total height of 7.05 m (23 ft 2 in). The boat displaced 493 t (485 long tons) when surfaced and 611 t (601 long tons) when submerged.
U-9 was fitted with two Körting 8-cylinder plus two Körting 6-cylinder two-stroke petrol engines with a total of 1,000 metric horsepower (735 kW; 986 bhp) for use on the surface and two Siemens-Schuckert double-acting electric motors plus two electric motors with a total of 1,160 PS (853 kW; 1,144 shp) for underwater use. These engines powered two shafts each with a 1.45 m (4.8 ft) propeller, which gave the boat a top surface speed of 14.2 knots (26.3 km/h; 16.3 mph), and 8.1 knots (15.0 km/h; 9.3 mph) when submerged. Cruising range was 1,800 nautical miles (3,300 km; 2,100 mi) at 14 knots (26 km/h; 16 mph) on the surface, and 80 nmi (150 km; 92 mi) at 5 knots (9.3 km/h; 5.8 mph) under water. Diving depth was 50 m (164 ft 1 in).
The U-boat was armed with four 50 cm (20 in) torpedo tubes, two fitted in the bow and two in the stern, and carried 6 torpedoes. Originally, the boat was equipped with a machine gun, which was augmented with a 3.7 cm (1.5 in) Hotchkiss gun when war broke out in 1914. In 1915, an additional 5 cm (2.0 in) gun was fitted. When U-9 underwent a major refit in 1916, two mine-laying rails were added, which were later removed again. The boat's complement was 4 officers and 31 enlisted.
On 16 July 1914, the crew of U-9 reloaded her torpedo tubes while submerged, the first time any submarine had succeeded in doing so. On 1 August 1914, Kapitänleutnant Otto Weddigen took command. On 22 September, while patrolling the Broad Fourteens, a region of the southern North Sea, U-9 found a squadron of three obsolescent British Cressy-class armoured cruisers (HMS Aboukir, HMS Hogue, and HMS Cressy), (sardonically nicknamed the "Live Bait Squadron") which had been assigned to prevent German surface vessels from entering the eastern end of the English Channel. She fired four of her torpedoes, reloading while submerged, and sank all three in less than an hour. 1,459 British sailors died. It was one of the most notable submarine actions of all time. Members of the Admiralty who had considered submarines mere toys no longer expressed that opinion after this event.
On 15 October, U-9 sank the protected cruiser HMS Hawke. On 12 January 1915, Johannes Spieß relieved Weddigen, and commanded U-9 until 19 April 1916. During this period, she sank 13 ships totalling 8,635 GRT: 10 small fishing vessels and three British steamers (Don, Queen Wilhelmina and Serbino).
After April 1916, she was withdrawn from front-line duties to be used for training.
Summary of raiding history
|Date||Ship Name||Nationality||Tonnage[Note 1]||Fate|
|22 September 1914||HMS Aboukir||Royal Navy||12,000||Sunk|
|22 September 1914||HMS Cressy||Royal Navy||12,000||Sunk|
|22 September 1914||HMS Hogue||Royal Navy||12,000||Sunk|
|15 October 1914||HMS Hawke||Royal Navy||7,350||Sunk|
|3 May 1915||Bob White||United Kingdom||191||Sunk|
|3 May 1915||Coquet||United Kingdom||176||Sunk|
|3 May 1915||Hector||United Kingdom||179||Sunk|
|3 May 1915||Hero||United Kingdom||173||Sunk|
|3 May 1915||Iolanthe||United Kingdom||179||Sunk|
|3 May 1915||Northward Ho||United Kingdom||180||Sunk|
|3 May 1915||Progress||United Kingdom||273||Sunk|
|4 May 1915||Rugby||United Kingdom||205||Sunk|
|5 May 1915||Straton||United Kingdom||198||Sunk|
|6 May 1915||Merrie Islington||United Kingdom||147||Sunk|
|8 May 1915||Don||United Kingdom||939||Sunk|
|8 May 1915||Queen Wilhelmina||United Kingdom||3,590||Sunk|
|16 August 1915||Serbino||United Kingdom||2,205||Sunk|
|5 November 1915||Dagö (n.4)||Imperial Russian Navy||1,080||Sunk|
- Helgason, Guðmundur. "WWI U-boat commanders: Otto Weddigen (Pour le Mérite)". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 13 March 2015.
- Helgason, Guðmundur. "WWI U-boat commanders: Johannes Spieß (Royal House Order of Hohenzollern)". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 13 March 2015.
- Gröner 1991, pp. 4-5.
- "Sinking of HMS Aboukir, Cressy and Hogue by U-9". World War 1 Naval Combat. Retrieved 2007-05-27.
- Farquharson-Roberts, Mike (2014). A History of the Royal Navy: World War I. I.B.Tauris. p. 8. ISBN 9781780768380. Retrieved 2014-12-01.
- Helgason, Guðmundur. "Ships hit by U 9". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 19 February 2014.
- Beesly, Patrick (1982). Room 40: British Naval Intelligence 1914–1918. London: H Hamilton. ISBN 978-0-241-10864-2.
- Fitzsimons, Bernard, ed. The Illustrated Encyclopedia of 20th Century Weapons and Warfare, "U-Boats (1905–18), Volume 23, p. 2534. London: Phoebus Publishing, 1978.
- Gröner, Erich; Jung, Dieter; Maass, Martin (1991). U-boats and Mine Warfare Vessels. German Warships 1815–1945 2. Translated by Thomas, Keith; Magowan, Rachel (London: Conway Maritime Press). ISBN 0-85177-593-4.*Halpern, Paul G. (1995). A Naval History of World War I. New York: Routledge. ISBN 978-1-85728-498-0.
- 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.
- Rössler, Eberhard (1985). U-Bootbau bis Ende des 1. Weltkriegs, Konstruktionen für das Ausland und die Jahre 1935–1945. Die deutschen U-Boote und ihre Werften (in German) I (Koblenz: Bernard & Graefe). ISBN 3-7637-5213-7.
- Roessler, Eberhard (1997). Die Unterseeboote der Kaiserlichen Marine. Bonn: Bernard & Graefe. ISBN 978-3-7637-5963-7.
- Schroeder, Joachim (2002). Die U-Boote des Kaisers. Bonn: Bernard & Graefe. ISBN 978-3-7637-6235-4.
- Spindler, Arno (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.
- Photos of cruises of German submarine U-54 in 1916–1918.
- A 44 min. German film from 1917 about a cruise of the German submarine U-35.
- 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.
- Helgason, Guðmundur. "WWI U-boats: U 9". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 2007-05-27.