Design
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.
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.
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).
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.
Operations
SM U-33Kptlt. 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]
German Empire 
