HMS E55 was a British E-class submarine built by William Denny, Dumbarton as Yard No.1032. She was launched on 5 February 1916 and was delivered on 25 March 1916. E55 was sold for scrap at Newcastle on 6 September 1922.

Design

Like all post-E8 British E-class submarines, E55 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 eight-cylinder two-stroke diesel engines and two 420 hp electric motors made by Bellis & Marcom. 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. E55 was capable of operating submerged for five hours when travelling at 5 kn. E55 was constructed with a 12-pounder 76 mm QF gun mounted forward of the conning tower, although this was later removed. She had 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.

Service

E55 joined the 8th Submarine Flotilla, part of the Harwich Force, following commissioning. In mid-April 1916, E55 was fitted with knife-edged hydroplanes and bow for experiments in net cutting, which allowed the effectiveness of different types of anti-submarine net to be evaluated. On 3 May, E55 left Harwich to patrol off Terschelling as part of Operation XX, a large scale operation in which a seaplane attack on Tondern would be carried out in an attempt to lure the German High Seas Fleet out to sea where it could be attacked. E55 saw nothing of interest during the operation. On 30 May 1916, the eve of the Battle of Jutland, E55, together with HMS E26 and HMS D1, set out from Harwich to patrol off the Vyl Lightvessel. E55 arrived near Horns Rev on 31 May, and after sighting a German airship, settled to the bottom to save her batteries, and although several explosions were heard, nothing was seen during daylight on 1 June. On the afternoon of 2 June, E55 spotted the German submarine SMU U-64, and fired a single torpedo which missed. On 29 July 1916, E55 attacked a German submarine off the Schouwen Bank, but two torpedoes missed while a third stuck in the torpedo tube and could not be launched. In August 1916, the Royal Navy reorganised its submarine flotillas, with the Harwich based submarines, including E55, joining the newly established 9th Submarine Flotilla. E55 remained part of the 9th Flotilla until the end of the war. In May 1919, E55 was listed as part of the 3rd Submarine Flotilla, part of the Atlantic Fleet. E55 was sold for scrap on 6 September 1922.