Unit History: 19-01-1917: E36 and E43 left Harwich at 0730 for two patrol areas off Terschelling. A strong north easterly was blowing. At 1126 just before they left the coast, E43 signalled to E36 to proceed independently. At 1330 E36 was on the port beam but was out of sight by 1500. The sea was running fairly high and at 1850 E43, having lost her bridge screen, eased to 5 knots and turned 16 points to fit a new one. This delay must have enabled E36 to overtake her, for at 1950 off the Haaks LV, E43 had just altered course to true north when she suddenly sighted a submarine 3 points on the port bow apparently steering east and only 50 yards off. The helm was put hard to starboard and engines full astern but E43 struck E36 aft from the stern, rode right over her and saw her vanish on the starboard quarter in the darkness. E43 went astern but nothing could be seen in the darkness and heavy sea and nothing more was seen or heard of E36 –until the sighting of this probable wreckage. The site of the wreck is where a lot of people fish and it is likely that unexplored torpedos are still on board, according to a report by War History Online. Slow and fragile British submarines had an ill-fated start in the First World War and their development in the years leading up to the war brought many issues. At the start of the 1900s, submarines were very crude machines and they were slow, fragile and only able to dive for a couple of hours at a time. However, with torpedoes they posed a serious threat to other ships. During World War I, Britain lost 54 submarines with 137 in service. The German Navy had 134 operational U-boats and these managed to sink 192 boats, killing more than 5,400 people. At the start of the war, submarines were supposed to abide by international rules, which attempted to allow the crews of merchant ships to get to safety their vessels sunk. But, this became impractical and unrestricted submarine warfare was adopted by Germany, which, nearly brought Britain down in 1917. Over the following 18 years they did develop technically and the standard design of 1918 remained very similar to those used at the start of World War Two. Such was the success of the E-class design like the one found, that the L-class that was used in the Second World War was near enough a carbon-copy of the E-class, only bigger. British E-class Submarine The E-class submarines were very similar but an improvement to the D-class - Britain’s first overseas submarine with a diesel engine and the ability to carry more torpedos. The E-class subs though, were fitted with a twelve-pounder gun and had additional torpedo tubes. The main submarine used by the Submarine Service in World War One, the E-Class saw action in the Atlantic, Baltic, Dardanelles and the North Sea. In total 58 were built. The E-class went through several modifications as submarine technology improved, and all modifications were installed by the time the final group was under construction. The E-class served in the North Sea and the Baltic and Turkish operations while some served with Russian ships in Russian coastal waters before they moved to avoid capture by the communists who were gradually taking control of Russia. As the backbone of the submarine fleet, the E-class served with the Royal Navy throughout World War I, eventually replaced by the British L class submarine. All the E-class submarines were withdrawn from service by 1922. Source: War History Online Did any of your relatives serve on a Royal Navy submarine during World War I? Search the Forces War Records site and evolve your research. Alternatively, search our ‘historic document library’ where you will find a range of documents relating to World War I and also the Navy, including the Naval Annual 1913.