HMS Minotaur ( 1863 ) HMS " Minotaur " was the lead ship of the armoured frigate s built for the Royal Navy during the 1860s . They were the longest single - screw warships ever built . " Minotaur " took nearly four years between her launching and commissioning because she was used for evaluations of her armament and different sailing rigs . The ship spent the bulk of her active career as flagship of the Channel Fleet , including during Queen Victoria ' s Golden Jubilee Fleet Review in 1887 . She became a training ship in 1893 and was then hulked in 1905 when she became part of the training school at Harwich . " Minotaur " was renamed several times before being sold for scrap in 1922 and broken up the following year . Design and description . The " Minotaur " - class armoured frigates were essentially enlarged versions of the ironclad with heavier armament , armour , and more powerful engines . They retained the broadside ironclad layout of their predecessor , but their sides were fully armoured to protect the 50 guns they were designed to carry . Their plough - shaped ram was also more prominent than that of " Achilles " . The " Minotaur " - class ships were long between perpendiculars and long overall . They had a beam of and a draft of . The ships displaced . The hull was subdivided by 15 watertight transverse bulkheads and had a double bottom underneath the engine and boiler rooms . " Minotaur " was considered " an excellent sea - boat and a steady gun platform , but unhandy under steam and practically unmanageable under sail " as built . Steam - powered steering improved her maneouvring qualities significantly when it was installed in 1875 and she was judged " one of our very best manoeuvrers we have in the Navy " by Vice Admiral Philip Colomb in 1890 . The ship ' s steadiness was partially a result of her metacentric height of . Propulsion . " Minotaur " had a two - cylinder trunk steam engine , made by John Penn and Sons , that drove a single propeller . Ten rectangular fire - tube boiler s provided steam to the engine at a working pressure of . The engine produced a total of during the ship ' s sea trials on 10 May 1867 and " Minotaur " had a maximum speed of . The ships carried of coal , enough to steam at . " Minotaur " was reboilered in 1893 and reached with . The ship had five masts and a sail area of . Because her propeller could only be disconnected and not hoisted up into the stern of the ship to reduce drag , " Minotaur " only made under sail . Both funnels were semi - retractable to reduce wind resistance while under sail . Admiral George A . Ballard described " Minotaur " and her sisters as " the dullest performers under canvas of the whole masted fleet of their day , and no ships ever carried so much dress to so little purpose . " In 1893 – 4 , after her withdrawal from active service , " Minotaur " had two masts removed and was re - rigged as a barque . Armament . The armament of the " Minotaur " - class ships was intended to be 40 rifled 110 - pounder breech - loading guns on the main deck and 10 more on the upper deck on pivot mounts . The gun was a new design from Armstrong , but proved a failure a few years after its introduction . The gun was withdrawn before any were received by any of the " Minotaur " - class ships . They were armed , instead , with a mix of and rifled muzzle - loading guns . All four nine - inch and 20 seven - inch guns were mounted on the main deck while four seven - inch guns were fitted on the upper deck as chase gun s . The ship also received eight brass howitzers for use as . The gun ports were wide which allowed each gun to fire 30° fore and aft of the beam . The shell of the 14 - calibre 9 - inch gun weighed while the gun itself weighed . It had a muzzle velocity of and was credited with the ability to penetrate a of wrought iron armour at the muzzle . The 16 - calibre 7 - inch gun weighed and fired a shell . It was credited with the ability to penetrate armour . " Minotaur " was rearmed in 1875 with a uniform armament of 17 nine - inch guns , 14 on the main deck , two forward chase guns and one rear chase gun . The gun ports had be enlarged to accommodate the larger guns by hand , at a cost of £250 each . About 1883 two breech - loading guns replaced two 9 - inch muzzle - loading guns . Four quick - firing ( QF ) 4 . 7 - inch ( 120 - mm ) guns , eight QF 3 - pounder Hotchkiss guns , eight machine gun s and two torpedo tube s were installed in 1891 – 2 . Armour . The entire side of the " Minotaur " - class ships was protected by wrought iron armour that tapered from at the ends to amidships , except for a section of the bow between the upper and main decks . The armour extended below the waterline . A single 5 . 5 - inch transverse bulkhead protected the forward chase guns on the upper deck . The armour was backed by of teak . Construction and service . HMS " Minotaur " was originally ordered on 2 September 1861 as HMS " Elephant " , in honour of the ship once commanded by Nelson seventy years before , but her name was changed to " Minotaur " during construction . She was laid down on 12 September 1861 by the Thames Ironworks in Blackwall , London . She was launched on 12 December 1863 , commissioned in April 1867 and completed on 1 June 1867 . The lengthy delay in completion was due to frequent changes in design details , and experiments with her armament and with her sailing rig . The ship cost a total of £478 , 855 . " Minotaur " finally commissioned in Portsmouth as the flagship of the Channel Fleet , a position which she retained until 1873 . In 1868 the ship nearly rammed the ironclad as they were leaving Belfast Lough . " Minotaur " lost her bowsprit and fore topgallant mast , but " Bellerophon " only suffered some minor flooding . She paid off for a long refit in 1873 and resumed her position in 1875 when she rejoined the Channel Fleet . " Minotaur " became the first ship in the Royal Navy to receive a permanent installation of an electric searchlight in 1876 . The ship was the flagship of Vice Admiral Sir William Hewett , who had earned the Victoria Cross in the Siege of Sevastopol in 1854 , during Queen Victoria ' s Golden Jubilee Fleet Review on 23 July 1887 . " Minotaur " was paid off at the end of 1887 in Portsmouth and assigned to the Reserve until 1893 when she became a training ship at Portland . She was renamed HMS " Boscawen II " in March 1904 and transferred in 1905 to Harwich as part of the HMS " Ganges " training school . The ship was renamed 11 June 1906 as HMS " Ganges " and then to " Ganges II " on 25 April 1908 . She was sold on 30 January 1922 for scrap .