SM U-41 (Germany)

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.[2]

U-41 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-41 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 6 torpedoes. Additionally U-41 was equipped in 1915 with one 8.8 cm (3.5 in) Uk L/30 deck gun. The boat's complement was 4 officers and 31 enlisted.[2]

U-41 was sunk by British Q-ship on 24 September 1915 in the Second Baralong Incident. At this stage in the war, U-boat commanders were under orders to scrupulously observe the rules of war (the "cruiser rules"). After spotting merchant targets, submarines surfaced nearby, boarded the ships, and searched for contraband. This prevented the sinking of neutral vessels, but exposed the submarines to great risk.

After stopping 6,651 gross register tons (GRT) merchantman Urbino, U-41 sent a boarding party aboard to inspect the cargo. After finding war material on board, the Germans put the merchant crew off the ship in the lifeboats. U-41 was in the process of sinking Urbino with gunfire when HMS Wyandra (in the guise of the American-flagged merchantman Baralong) arrived on the scene, flying an American flag. When U-41 approached, Wyandra, fired on and sank the U-boat without striking the American flag. This was a violation of the rules of war; while the use of a False Flag was allowed,[3] it was required that a belligerent identify itself before initiating hostilities.

The event generated widespread outrage in Germany, especially among Kriegsmarine officers. The sinking was also commemorated in a propaganda medal designed by the German medallist Karl Goetz.

• 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.

• Helgason, Guðmundur. "WWI U-boats: U 41". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net.
• Historic England project to research First World War Submarine wrecks
• Howell, D; Croce, P (2014) 'UB-41 and UB 75, off Robin Hood's bay: Marine Geophysical Survey Report', Wessex Archaeology
• SS Urbino Wreck Site