HMS E12 was a British E class submarine built by HM Dockyard, Chatham. She was laid down on 16 December 1912 and commissioned on 14 October 1914. Her construction costs totalled £101,900. During the Great War, anti-submarine nets in the Dardanelles entangled her forward hydroplanes, forcing her down to a depth of 245 feet. At the time, this was the greatest depth achieved by any British submarine. E12 managed to surface only to come under fire by shore batteries, but avoided further damage. She survived the war and was sold for scrap in Malta on 7 March 1921.

Design

Like all post-E8 British E-class submarines, E12 had a displacement of 662 LT at the surface and 807 LT while submerged. She had a total length of 180 ft and a beam of 22 ft. She was powered by two 800 hp Vickers eight-cylinder two-stroke diesel engines and two 420 hp electric motors. The submarine had a maximum surface speed of 16 kn and a submerged speed of 10 kn. British E-class submarines had fuel capacities of 50 LT of diesel and ranges of 3255 mi when travelling at 10 kn. E12 was capable of operating submerged for five hours when travelling at 5 kn. E12 was armed with a single 4-inch QF gun mounted forward of the conning tower, and five 18 inch (450 mm) torpedo tubes, two in the bow, one either side amidships, and one in the stern; a total of 10 torpedoes were carried. E-Class submarines had wireless systems with 1 kW power ratings; in some submarines, these were later upgraded to 3 kW systems by removing a midship torpedo tube. Their maximum design depth was 100 ft although in service some reached depths of below 200 ft. Some submarines contained Fessenden oscillator systems.

Crew

Her complement was three officers and 28 men.