SM U-33 (Germany)

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]

On 28 March 1915, U-33 ordered the Great Eastern Railway's SS Brussels to stop.^[3] Instead of doing so, her captain, Charles Fryatt, ordered full steam ahead and attempted to ram U-33, which only just managed to dive in time.^[4]

On 30 March,^[5] 1916 the Russian hospital ship Portugal was towing a string of small flat-bottomed boats to ferry wounded from the shore to the ship. Off Rizeh, on the Turkish coast of the Black Sea she had stopped as one of the small boats was sinking and repairs were being made. The ship was not carrying wounded at the time, but had a staff of Red Cross workers on board, as well as her usual crew.^[6] | The ship's crew saw a periscope approaching the vessel but as the ship was a hospital ship and protected by the Hague conventions no evasive actions were taken. Without warning SM U-33 fired a torpedo which missed. The submarine came around again fired a torpedo from a depth of 30 feet, which hit near the engine room, breaking the ship into two pieces.^[6] Of 273 persons on board, 158 were rescued.^[5]

SM U-33 Kptlt. Gausser until Autumn 1917, then to U-156; next C.O. probably Kptlt. Siess.

U-33 came off the stocks at Kiel about the end of November 1914, and joined the Kiel School for trials before proceeding to Emden on 12 January 1915. She was attached to the 4th Half Flotilla.^[7] 24–25 January 1915, it was on patrol in the Bight, an area where enemy battlecruisers were reported.^[7] On 30 January 1915, departed on "Special anti-submarine patrol" but returned owing to engine trouble.^[7]

Further patrols in Bight were made on 18–20 February and 21-22 February 1915l.^[7]

From 27 February – 10 April 1915 U-33 passed through the English Channel and into the 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 Flotilla.^[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. Intercepted a neutral Greek ship between Piraeus and Messina and took as prisoner Stanley Wilson, a 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 en route attacked by a naval trawler on 1 November at about 36°35'E. She steered northabout and by the Sound, at some time with UB-51 and UB-105.^[7] At the end of the war, U-33 was surrendered to British 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. Vol. 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: Archived 15 October 2018 at the Wayback Machine original documents, photos and maps about World War I German submarine warfare and British Room 40 Intelligence from The National Archives, Kew, Richmond, UK.