Duke of Edinburgh - class cruiser The " Duke of Edinburgh " - class cruiser was a class of two armoured cruiser s built for the Royal Navy in the first decade of the 20th Century . They were the first British armoured cruisers designed to work with the battlefleet rather than protect merchant shipping . After commissioning , they were assigned to the Atlantic , Channel and Home Fleet s until 1913 when they were transferred to the Mediterranean Fleet . After the start of World War I in August 1914 , the sister ships participated in the pursuit of the German battlecruiser and light cruiser . After the German ships reached their refuge in Ottoman Turkey , the ships were ordered to the Red Sea for convoy escort duties . They captured three German merchant ships before they returned to home at the end of the year . The sisters participated in the Battle of Jutland in May 1916 where was sunk with all hands . spent the next year on blockade duties in the North Sea before she was transferred to the Atlantic Ocean on convoy escort duties for the rest of the war . She was sold for scrap in 1920 . Design and description . After the preceding " Devonshire " class , the Royal Navy rethought how it planned to use its armoured cruisers . It decided that they were going to form a fast wing of the battlefleet which meant that they required heavier armour and armament to fight their counterparts in opposing fleets and thus larger and more expensive . Two armoured cruisers were planned for the 1902 – 1903 Naval Programme and the newly appointed Director of Naval Construction , Philip Watts designed what naval historian Oscar Parkes called : " cruiser editions of the s " . In these , his first design , he perpetuated the worst feature of the designs by his predecessor , Sir William White , by placing the secondary armament of guns in embrasure s a deck below the main armament which meant that the guns were inoperable in anything more than a dead calm sea . A solution for this problem was offered after construction began when Watts learned that the ships would be lighter than expected and that weight would be available to replace the six - inch guns with guns raised to the same deck as the main armament . The change would cost a total of £398 , 000 for the two ships , far too expensive for the Board of Admiralty , so it was rejected on 30 March 1904 . The " Duke of Edinburgh " - class ships were designed to displace , but they proved to be significantly lighter as built , displacing at normal load and fully loaded . The ships had an overall length of and a length between perpendiculars of . They had a beam of and a deep draught of forward and aft . The class was over longer overall than the " Devonshire " s and displaced over more . The ships ' complement was 769 officers and enlisted men . They roll ed quickly with a metacentric height of at deep load and their six - inch guns were as wet as predicted . The cruisers were powered by two 4 - cylinder triple - expansion steam engines , each driving one shaft , which produced a total of and gave a maximum speed of . The engines were powered by 20 Babcock & Wilcox water - tube boilers and six cylindrical boilers . The ships carried a maximum of of coal and an additional of fuel oil that was sprayed on the coal to increase its burn rate . At full capacity , they could steam for at a speed of . Armament . The " Duke of Edinburgh " s main armament consisted of six 45 - calibre BL 9 . 2 - inch Mk X guns in single - gun turret s , a much more powerful gun than used in the " Devonshire " s . The guns were distributed in two centreline turrets , one each fore and one aft of the superstructure , and four wing turret s disposed in the corners about the funnels . The centreline turrets could traverse a total of 285° while the wing turrets were limited to about 120° on the broadside due to muzzle blast . The gun had an elevation range of −5° to + 15° . The shell weighed and was fired at a maximum muzzle velocity of . This gave it a range of at maximum elevation . The gun ' s rate of fire was about three rounds per minute and the ships carried 100 rounds for each gun . Their secondary armament of ten 50 - calibre BL 6 - inch Mk XI guns was arranged in single embrasures . They were mounted amidships on the main deck and were only usable in calm weather . The guns could only traverse about 120° on the broadside . They initially had a maximum elevation of + 13° , but this was later increased to + 20° . This gave them a range of at an elevation of + 15° with their shell . Each gun was provided with 150 rounds . Twenty Vickers quick - firing ( QF ) 3 - pounder guns were fitted for defence against torpedo boat s , six on turret roofs and fourteen in the superstructure , all on pivot mounts . These guns were too small to be useful against the torpedo boats before they got within torpedo range . They fired a shell that weighed and was fired at a maximum muzzle velocity of . This gave it a range of at an elevation of + 20° . 250 rounds were carried for each gun . The ships also mounted three submerged 18 - inch torpedo tube s . They carried a total of eighteen torpedoes in addition to the six torpedoes that could be used by the two steam pinnace s . Armour . The " Duke of Edinburgh " - class ships had a waterline armour belt of Krupp cemented armour that covered of the hull amidships . It covered the side of the ship up to the upper deck , a height of above the waterline and reached below it . Between the central citadel and the bow , the belt armour was thick and it extended to the stern with a thickness of . Transverse bulkheads six inches thick protected the citadel from raking fire . The faces of the gun turrets were 7 . 5 inches thick with sides and a roof . The barbette s were protected by six inches of armour as were the ammunition hoists , although the armour for those thinned to three inches between the armour belt . Two - inch armour screens separated each of the six - inch guns . The thickness of the lower deck was only except for a patch of armour over the steering gear and another thick over the engine cylinders . The sides of the conning tower were thick . Modifications . The funnels proved to be too short in service and they were raised about four years after completion to keep the superstructure smoke - free in a following wind . In March 1916 , both ships had all their six - inch guns removed , the embrasures plated over , and six of the guns were remounted on the upper deck . In May 1917 , two more were added to " Duke of Edinburgh " on the forecastle . The ship ' s foremast was converted to a tripod mast to support the weight of the fire - control director probably added in 1917 . Service . " Duke of Edinburgh " and " Black Prince " served in the Channel , Atlantic and Home Fleets before World War I . They were stationed in the Mediterranean when World War I began and participated in the pursuit of the " Goeben " and " Breslau " as part of the 1st Cruiser Squadron , but was ordered not to engage . After the German ships reached Ottoman waters , the ships were sent to the Red Sea in mid - August to protect troop convoys arriving from India . While on escort duty they captured three German merchantmen . The two sisters rejoined the 1st Cruiser Squadron in December 1914 , which had transferred to the Grand Fleet and participated in the Battle of Jutland in May 1916 . " Black Prince " became separated from the fleet when darkness fell and was sunk with all hands by German battleships later that night . " Duke of Edinburgh " was not damaged during the battle and was the only ship of her squadron to survive . After Jutland " Duke of Edinburgh " was ordered to reinforce the patrols north of the Shetland Islands against German blockade runner s and commerce raiders . She was eventually transferred to the Atlantic in August 1917 for convoy escort duties . The ship was sold for scrap in 1920 .