Roon - class cruiser The " Roon " class was a pair of armored cruiser s built for the German Imperial Navy after the turn of the 20th century . The class comprised and , which closely resembled the earlier ships , but incorporated slight incremental improvements . The ships were easily distinguished from their predecessors by the addition of a fourth funnel . Like all of the armored cruisers built by Germany , they were intended to serve as station ships in Germany ' s overseas possessions . The ships did not compare well with their British rivals . The two ships served with the High Seas Fleet in the reconnaissance squadrons after they joined the fleet in 1905 – 1906 . At the outbreak of World War I in 1914 , the ships served alongside the more powerful battlecruiser s of the I Scouting Group . While returning to port after a raid of the English coast on 16 December 1914 , " Yorck " struck German mines and sank with heavy loss of life . " Roon " was disarmed in 1916 and intended to be converted into a seaplane carrier , though this was never carried out . The ship was eventually broken up for scrap in 1921 . Design . Design work on " Roon " and her sister ship " Yorck " was completed in 1901 . The design for the " Roon " class can be traced back to the first German armored cruiser , , built between 1896 – 1900 , and the preceding of protected cruiser s that came before it . The German armored cruisers were designed for overseas service , specifically to serve as station ships in the German colonies in Africa , Asia , and the Pacific . " Roon " and her sister " Yorck " were improved versions of the preceding " Prinz Adalbert " class . The two ships were slightly larger and faster than the " Prinz Adalbert " class and had a slightly different armor layout ; the " Roon " class ships had thinner armor on the turret faces , and slightly thinner armored decks . They shared many of the same layout characteristics as the contemporary German pre - dreadnought battleship s , including a smaller main armament but heavier secondary battery than their foreign equivalents . As a result , they compared unfavorably with their British contemporaries . Taylor describes the ships as " poorly protected and not a successful class in service . " General characteristics . The ships of the " Roon " class were long at the waterline and overall . They had a beam of and a draft of . " Roon " and " Yorck " displaced normally , and at full load . Their hulls were constructed from transverse and longitudinal steel frames that formed a structure over which the steel hull plates were riveted . The hulls contained 12 watertight compartments and a double bottom that ran for 60 percent of the length of the ship . Like the preceding " Prinz Adalbert " - class ships , " Roon " and " Yorck " were good sea boats ; when the fuel bunkers were full they had a gentle motion . They also maneuvered well and were responsive to the helm . With the rudder hard over , the ships lost up to 60 percent speed . The ships ' casemate s were placed too low , and as a result they were exceedingly wet ; the casemate guns were impossible to use in heavy seas . They had a metacentric height of . The ships ' standard complements numbered some 35 officers and 598 enlisted men . While serving as a squadron flagship the crew was augmented by 13 officers and 62 men , and as a second command ship by 9 officers and 44 sailors . Propulsion . " Roon " and " Yorck " were powered by the same engine system as the preceding class , three 3 - cylinder vertical triple expansion engines , each of which drove one of the ships ' three screws . The central screw was in diameter , and the outer screws were . Steam was provided to the engines by 16 boilers built by Düsseldorf - Ratinger Röhrenkesselfabrik ( Dürr ) . Each boiler had 4 fireboxes apiece for a total of 48 . The propulsion system produced , which delivered a top speed of . The ships had four turbo generators , which provided 260 kilowatts at 110 volts . The ships had a single rudder . Armament . The ships ' primary armament consisted of four SK L / 40 guns mounted in two twin turrets , one fore and one aft . These guns fired a armored - piercing shell at a muzzle velocity of per second , for a maximum range of with their original maximum elevation of 16 degrees . The guns were later improved to 30 degrees , which extended the maximum range to . Secondary armament included ten SK L / 40 guns in single turrets and casemates and fourteen SK L / 35 guns , also casemated . The 15 cm guns fired a shell at a muzzle velocity of per second . The guns could be elevated to 30 degrees , which provided a maximum range of . The 8 . 8 cm guns fired a shell at a muzzle velocity of per second . These guns had a maximum elevation of 25 degrees and a range of . The ships were also equipped with four torpedo tubes . This armament was identical to that on the preceding , with the exception of ammunition stores . The " Roon " - class ships carried 380 shells for the main battery , 1 , 600 rounds for the 15 cm guns , and 2 , 100 shells for the 8 . 8 cm guns . The planned conversion for " Roon " to a seaplane carrier called for six 15 cm L / 45 guns and six 8 . 8 cm Flak guns , with 2 , 400 rounds , though this was never carried out . Armor . " Roon " and " Yorck " were protected by Krupp cemented steel armor . At the waterline , their armored belt was thick amidships were the ships ' vitals were located . This was decreased slightly to on either end of the central section of the belt . The belt was backed by of teak planking . At the casemate deck the side armor was also 100 mm thick . The armored deck ranged in thickness from and was connected to the belt by sloped armor that was thick . The forward conning tower had thick sides and a thick roof . The rear conning tower was less well - protected ; its sides were only 80 mm thick and its roof was thick . The main battery gun turrets were armored with 150 mm thick steel plates on the sides and 30 mm thick roofs . The 15 cm turrets were protected by 100 mm thick sides and 80 mm thick gun shields . Construction . " Roon " was laid down in 1902 at the Kiel Navy dockyard . She was launched on 27 June 1903 and completed on 5 April 1906 , at the cost of 15 , 345 , 000 marks . " Yorck " was laid down in February 1903 , at Blohm & Voss shipyard . " Yorck " was launched on 14 May 1904 and completed on 21 November 1905 at a cost of 16 , 241 , 000 marks . " Roon " was laid down as " Ersatz Kaiser " , as a replacement for the old armored frigate , which had been renamed " Uranus " and used as a harbor ship . " Yorck " was ordered as " Ersatz Deutschland " to replace , the sistership to " Kaiser " , which had renamed " Jupiter " and converted into a target ship . Service history . SMS " Roon " . After commissioning into the fleet , was assigned to the I Scouting Group . In 1908 , she served as the flagship for Rear Admiral Jacobsen in the second division . " Roon " served here until 1912 when she was replaced by the new battlecruiser . At the start of World War I , " Roon " was serving as the flagship of the III Scouting Group . The ship participated in several actions during World War I , including the raid on Scarborough , Hartlepool and Whitby , during which she served in the cruiser screen for the dreadnought s of the High Seas Fleet . " Roon " also conducted operations against Russian forces in the Baltic Sea , including bombardments against the Russian positions at Libau in support of the army in May 1915 . The Battle of the Åland Islands took place between " Roon " and several other German cruisers and Russian forces led by the powerful cruiser " Rurik " . in July 1915 . In August " Roon " and bombarded Russian positions in the Baltic and briefly engaged several Russian destroyer s . After 1916 , " Roon " was disarmed and used as a guard ship and floating barracks in Kiel until the end of the war . Design work commenced in 1916 to convert the ship into a seaplane carrier ; work was planned to last from 1917 to 1918 during a period of 20 months . The ship was struck from the naval register on 25 November 1920 and scrapped the following year at Kiel - Nordmole . SMS " Yorck " . also served in the I Scouting Group with her sister ship , in the second division . In 1908 , the ship won the annual " Kaiser ' s Challenge Cups for Prize Firing " for the reconnaissance squadron . In 1911 , the ship came under the command of Franz von Hipper , who would go on to command the I Scouting Group during the war . Hipper held this position aboard " Yorck " from 1 October 1911 to 26 January 1912 . In early 1912 the ship was decommissioned and her crew was transferred to the new battlecruiser . The ship had a short career during World War I . At the outbreak of war , " Yorck " was brought out of the reserve fleet and joined her sistership " Roon " in the III Scouting Group . After the raid on Scarborough , Hartlepool and Whitby , the ship made a navigational error upon returning to the Jadebusen , and accidentally sailed into a German defensive minefield . The ship sank quickly and only 127 men of her complement of 629 were rescued . The wreck was cleared over several periods between 1929 and the mid - 1980s . The first period of work lasted from 1929 – 30 ; work commenced briefly in 1965 . The final work on removing the ship began in 1982 .