During February 1915, she carried out acceptance trials at Kiel,[2] and was attached to the 2d Half-Flotilla in the North Sea in March.[2]
Design
German Type U 31 submarines were double-hulled ocean-going submarines similar to Type 23 and Type 27 subs in dimensions and differed only slightly in propulsion and speed. They were considered very good high sea boats with average manoeuvrability and good surface steering.[3]
U-36 had an overall length of 64.70 m (212 ft 3 in), her pressure hull was 52.36 m (171 ft 9 in) long. The boat's beam was 6.32 m (20 ft 9 in) (o/a), while the pressure hull measured 4.05 m (13 ft 3 in). Type 31s had a draught of 3.56 m (11 ft 8 in) with a total height of 7.68–8.04 m (25 ft 2 in – 26 ft 5 in). The boats displaced a total of 971 tonnes (956 long tons); 685 t (674 long tons) when surfaced and 878 t (864 long tons) when submerged.[3]
U-36 was fitted with two Germania 6-cylinder two-stroke diesel engines with a total of 1,850 metric horsepower (1,361 kW; 1,825 bhp) for use on the surface and two Siemens-Schuckert double-acting electric motors with a total of 1,200 PS (883 kW; 1,184 shp) for underwater use. These engines powered two shafts each with a 1.60 m (5 ft 3 in) propeller, which gave the boat a top surface speed of 16.4 knots (30.4 km/h; 18.9 mph), and 9.7 knots (18.0 km/h; 11.2 mph) when submerged. Cruising range was 8,790 nautical miles (16,280 km; 10,120 mi) at 8 knots (15 km/h; 9.2 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).[3]
SM U-36's movements and operations were monitored and reported by British Naval Intelligence, better known as "Room 40".[2] Her first war patrol was in Heligoland Bight from 29 to 30 March 1915; she reported no sinkings during this time.[2] On 23 April, she returned to Heligoland Bight, apparently from a North Sea patrol.[2][Note 2]
She departed on 29 April, bound again for the North Sea, where she sank the 1,966-ton DanishsteamerLilian Drost on 8 May, captured the 1,241-ton Swedish steamer Björn on 10 May as a prize, while capturing and releasing the 654-ton Dutch steamer Niobe the same day.[2]
U-36 returned to her North Sea station on 17 July. Operating off the north and northwest coast of Scotland, she sank three steamers and almost a dozen smaller vessels. On 22 July, the 3,644-ton RussianRubonia fell victim. That same day, U-36 also attacked a group of fishing vessels west of the Orkney Islands, sinking nine small trawlers and two sailing vessels, while taking one prize. The following day, the 1,505-ton FrenchmanDanae was stopped according to prize rules and sunk, and the 3,819-ton NorwegianFimreite was sunk as well.[2]
On the day she was sunk, U-36 intercepted and captured the AmericanwindjammerPass of Balmaha, bearing a cargo of cotton intended for Russia and en route to Kirkwall to be inspected by British authorities. An ensign from U-36 was left aboard the windjammer to ensure her successful passage to Cuxhaven. Pass was refitted as a merchant raider and re-christened Seeadler, commanded by Count Felix von Luckner,[4] soon to become famous for her naval exploits in the Atlantic and Pacific.
Fate
U-36 was sunk in the afternoon of 24 July 1915 in combat off the coast of North Rona in the Outer Hebrides with the British Q-ship[2][Note 3]Prince Charles, commanded by Lieutenant Mark Wardlaw, Royal Navy. The submarine had just stopped and boarded the Danish vessel SS Luise and a boarding party was in the process of dumping her cargo when a lookout sighted an approaching steamer. U-36 sailed towards the disguised Prince Charles and ordered her to stop while firing at her. The Q-ship complied, swinging out her boats. The unsuspecting submarine came within about 600 m (660 yd) of the ship when Prince Charles hoisted the British flag of war and commenced firing. Taken completely by surprise, U-36 took several direct hits and heavy damage, and sank. When Luise moved to pick up the survivors floating in the water, Prince Charles fired into her, believing her to be a German resupply vessel. Forty-five minutes after U-36 sank, the remaining survivors were picked up by the Q-ship. Kptlt. Graeff and 15 crewmen were saved, but 18 others were lost. U-36 was the first U-boat sunk by Q-ship, and one of only a handful to fall victim. Lieutenant Wardlaw received a Distinguished Service Order for the action, and two of his crew received Distinguished Service Medals. The merchant crew of the Q-ship was awarded a prize sum of £1,000, to be divided amongst themselves.[5]
Summary of raiding history
Artist's rendition of the captured American windjammer Pass of Balmaha reoutfitted as the merchant raider SMS Seeadler
^Helgason, Guðmundur. "WWI U-boat commanders: Ernst Graeff". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 11 January 2015.
^Pardoe, Blaine (2005). The Cruise of the Sea Eagle: The Amazing True Story of Germany's Gentleman Pirate. Cuilford, CT: The Lyons Press. p. 19. ISBN1592286941.
^Chatterton, E. Keble (1922). "Chapter II: The Beginning of Success". Q-ships and their story. London: Sidgwick and Jackson, Ltd. pp. 13–16.
^Helgason, Guðmundur. "Ships hit by U 36". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 11 January 2015.
Bibliography
Beesly, Patrick (1982). Room 40: British Naval Intelligence 1914–1918. London: H Hamilton. ISBN978-0-241-10864-2.
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. Vol. 2. Translated by Thomas, Keith; Magowan, Rachel. London: Conway Maritime Press. ISBN0-85177-593-4.*Halpern, Paul G. (1995). A Naval History of World War I. New York: Routledge. ISBN978-1-85728-498-0.
Bodo Herzog: Deutsche U-Boote 1906-1966. Manfred Pawlak Verlags GmbH, Herrschingen 1990, ISBN3-88199-687-7
Paul Kemp: Die deutschen und österreichischen U-Boot Verluste in beiden Weltkriegen. Urbes Verlag Hans Jürgen Hansen, Gräfelfing vor München 1998, ISBN3-924896-43-7
Koerver, Hans Joachim (2008). Room 40: German Naval Warfare 1914–1918. Vol I., The Fleet in Action. Steinbach: LIS Reinisch. ISBN978-3-902433-76-3.
Koerver, Hans Joachim (2009). Room 40: German Naval Warfare 1914–1918. Vol II., The Fleet in Being. Steinbach: LIS Reinisch. ISBN978-3-902433-77-0.
Roessler, Eberhard (1997). Die Unterseeboote der Kaiserlichen Marine. Bonn: Bernard & Graefe. ISBN978-3-7637-5963-7.
Schroeder, Joachim (2002). Die U-Boote des Kaisers. Bonn: Bernard & Graefe. ISBN978-3-7637-6235-4.
Spindler, Arno (1966) [1932]. 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.
External links
[1] Information on British Q-ships like Prince Charles.
Helgason, Guðmundur. "WWI U-boat Types: Type U 31". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net.
Helgason, Guðmundur. "WWI U-boats: U 36". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net.
German Empire
