German Type U 31 submarine


Type U 31 was a class of U-boats built during World War I by the Kaiserliche Marine.
Between 1912 and 1915 eleven were built on Germaniawerft in Kiel, amongst these top-three-scoring with the famous Lothar von Arnauld de la Perière as commander, with Walter Forstmann and with Max Valentiner. Together these U-boats sunk more than.
Later admiral and head of the Abwehr from 1935 to 1944 Wilhelm Canaris also served as commander on two different Type U 31 U-boats. He first took over from Max Valentiner on U-38 and later on.

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.
Type U-31s had an overall length of, their pressure hulls were long. The boats' beam was , while the pressure hull measured. Type 31s had a draught of with a total height of. The boats displaced a total of ; when surfaced and when submerged.
Type U-31s were fitted with two Germania 6-cylinder two-stroke diesel engines with a total of for use on the surface and two Siemens-Schuckert double-acting electric motors with a total of for underwater use. These engines powered two shafts each with a propeller, which gave the boats a top surface speed of, and when submerged. Cruising range was at on the surface, and at under water. Diving depth was.
The U-boats were armed with four torpedo tubes, two fitted in the bow and two in the stern, and carried 6 torpedoes. Most boats received one or two SK L/30 deck guns, which were later replaced with SK L/45 guns on some. The boats' complement was 4 officers and 31 enlisted.

List of Type U 31 submarines

There were eleven Type U 31 submarines commissioned into the Kaiserliche Marine.
BoatArmamentFate
no deck gunlost in January 1915 in the North Sea - Discovered 2012 off the East Anglia Coast and identified September 2015
two 8.8 cm guns, from 1916/17 one 10.5 cm gunsunk 5 May 1918 north-west of Malta
one 8.8 cm gun, from 1916/17 one 10.5 cm gunsurrendered 1919, scrapped
one 8.8 cm gun, from 1916/17 one 10.5 cm gunsunk October 1918 in the Mediterranean Sea
one 7.5 cm gun, one 10.5 cm gun surrendered 1918, scrapped
two 8.8 cm guns, from 1916/17 one 10.5 cm gunsunk 24 July 1915 west of Rona, Hebrides
two 8.8 cm guns, from 1916/17 one 10.5 cm gunsunk by mine in April 1915 in the English Channel
one 8.8 cm gun, from 1916/17 one 10.5 cm gunsurrendered 1919, scrapped
one 8.8 cm gun, from 1916/17 one 10.5 cm gunsunk 18 May 1918 off El Ferrol
one 8.8 cm gunsunk 23 June 1915 in the North Sea
one 8.8 cm gunsunk 24 September 1915 in the English Channel