SM U-33 (Germany)

German Type U 31 submarines were double-hulled ocean-going craft similar to Type 23 and Type 27 boats in dimensions, differing only slightly in propulsion and speed. They were considered very good high sea boats with average manoeuvrability and good surface steering.[2]

U-33 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.[2]

U-33 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).[2]

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 six torpedoes. Additionally U-33 was equipped in 1915 with one 8.8 cm (3.5 in) Uk L/30 deck gun, which was later replaced with a 10.5 cm (4.1 in) gun. The boat's complement was four officers and 31 enlisted.[2]

SM U-33 Kptlt. Gausser till Autumn 1917, then to U-156; next C.O. probably Kptlt. Siess. Came off the stocks at Kiel about the end of November 1914, and joined the Kiel School for trials, proceeding to Emden on 12 January 1915. She was attached to the 4th Half Flotilla.[7]

24–25 January 1915. On Bight patrol to an area where enemy battle cruisers were reported.[7]

30 January 1915 ? Special anti-submarine patrol. Returned owing to engine trouble.[7]

? 18–20 February 1915. Bight patrol.[7]

21–22 February 1915. Bight patrol.[7]

27 February – 10 April 1915. Through Channel to Atlantic. 2 S.S., 2 sailing vessels sunk.[7]

29–30 May 1915. North Sea returned owing to defective W/T.[7]

4–24 June 1915. Northabout to west coast of Scotland. Sank 2 S.S., 1 prize.[7]

14–17 August 1915. Bight Anti-air raid patrol.[7]

28 August – 15 September 1915. To Mediterranean northabout. Sank 5 S.S. Arrived Cattaro about 15 September and joined the Constantinople Half Flot.[7]

28 September – 9 October 1915. Cruise in eastern Mediterranean. Sank 10 S.S.[7]

16 November – 6 December 1915. Cruise in central Mediterranean. Sank 13 S.S. On 5 December was in action with drifter HOLLIBANK in the Straits of Otranto. Took prisoner Capt Wilson, King's messenger.[7]

April 1916 – November 1916. U-33 was operating chiefly in the eastern Black Sea and was based on Constantinople or Varna. By April 1917 she was back in the Adriatic.[7]

12 January – 10 February 1918. Left Cattaro and operated in eastern Mediterranean. Sank 2. S.S., 2 sailing vessels, and damaged but did not sink 2 S.S.[7]

1–17 May 1918. Left Cattaro for the east, and on 7 May was in area off Port Said. Sank 1 S.S., 1 sailing vessel, and attacked 2 ships and a convoy unsuccessfully. On May 8 was in action, and on 15 May broke off undertaking owing to defects.[7]

2 September to about 26 September. Left Cattaro for the east. Sank 1 S.S., 12 sailing vessels.[7]

On 19 October 1918. U-33 left Cattaro for Kiel. The only incident of the voyage was that she was attacked by a trawler on 1 November in about 36°35'E. She steered northabout and by the Sound, at some time with UB-51 and UB-105.[7]

Surrendered at Harwich January 16, 1919.[7]

• Room 40

• 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.
• 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.
• Beesly, Patrick (1982). Room 40: British Naval Intelligence 1914-1918. London: H Hamilton. ISBN 978-0-241-10864-2.
• Halpern, Paul G. (1933). A Naval History of World War I. New York: Routledge. ISBN 978-1-85728-498-0.
• 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.
• 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.

• Photos of cruises of German submarine U-54 in 1916-1918. Great photo quality, comments in German.
• A 44 min. film from 1917 about a cruise of the German submarine U-35. A German propaganda film without dead or wounded; many details about submarine warfare in World War I.
• Helgason, Guðmundur. "WWI U-boats: U 33". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net.
• 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.