HMS Pegasus ( 1917 ) HMS " Pegasus " was an aircraft carrier / seaplane carrier bought by the Royal Navy in 1917 during the First World War . She was laid down in 1914 by John Brown & Company of Clydebank , Scotland as SS " Stockholm " for the Great Eastern Railway Company , but construction was suspended by the start of the war . The ship was converted to operate a mix of wheeled aircraft from her forward flying - off deck and floatplanes that were lowered into the water . " Pegasus " spent the last year of the war supporting the Grand Fleet in the North Sea , but saw no combat . She spent most of 1919 and 1920 supporting British intervention against the Bolsheviks in North Russia and the Black Sea . The ship remained with the Mediterranean Fleet until 1924 , but was placed in reserve in 1925 after a brief deployment to Singapore . " Pegasus " was sold for scrap in 1931 . Design and description . The ship had an overall length of , a beam of , and a draught of at deep load . She displaced . Her two direct - drive steam turbines , each driving a propeller shaft , were designed to produce a total of and a speed of . On sea trials in December 1914 , " Pegasus " made and reached . The ship was converted from coal to fuel oil at the suggestion of her builders . She carried of oil which meant that she could steam for at her maximum speed . Her crew numbered 258 , including 100 aviation personnel . " Pegasus " s main armament consisted of four 40 - calibre , 12 - pounder 12 cwt guns . Two of these were mounted on the forecastle as low - angle guns , but the other two were mounted aft as anti - aircraft guns . They fired projectiles at a muzzle velocity of ; this gave a maximum range of against surface targets and an anti - aircraft range of . They had a rate of fire of 15 rounds per minute . HMS " Pegasus " was fitted with a flying - off deck forward , intended for aircraft with wheeled undercarriages , and a prominent hangar aft . Two electric cranes were fitted aft and a twin - boom derrick forward to handle her aircraft . The smaller forward hangar was built under the ship ' s bridge and the aircraft were raised to the flight deck overhead by one of the first lifts in the Royal Navy . The forward hangar could fit five single - seat fighters and the rear hangar had a capacity of four floatplane s . The ship could lower them into the water while steaming at and recover the floatplanes at . When " Pegasus " commissioned in 1917 she was assigned four Short Type 184 torpedo bomber s and four Beardmore W . B . III fighters . In late 1918 she carried four Sopwith Camel 2F . 1 , one Type 184 and three Fairey Campania reconnaissance aircraft . In 1919 she began to operate various models of the Fairey III . " Pegasus " carried of petrol for her aircraft . Her magazine s had the capacity for eight torpedo s , 72 , 108 , and 68 , later 84 , bombs . Career . HMS " Pegasus " was laid down in 1914 by the John Brown & Company of Clydebank , Scotland as SS " Stockholm " for the Great Eastern Railway Company , but her construction was suspended by the beginning of the First World War . The ship was purchased by the Royal Navy on 27 February 1917 and was launched on 9 June 1917 . She was commissioned on 14 August 1917 and completed on 28 August 1917 . She joined the Grand Fleet on completion and was assigned to support the Battle Cruiser Force . She participated in a few uneventful operations in the North Sea , but was mostly occupied with pilot training and ferrying aircraft to ships equipped with flying - off platforms . " Pegasus " supported the British intervention in the Russian Civil War between May to September 1919 and was based at Archangel . The ship returned to Rosyth and was briefly decommissioned . She recommissioned on 2 December 1919 and was transferred to the Mediterranean Fleet in March 1920 . " Pegasus " ran aground on 9 March off Kerch , but was pulled off without suffering any significant damage . She supported the evacuation of Novorossiysk by the Whites later that month and remained with the fleet until 1924 . In 1923 the forward flying - off deck was removed and the ship was re - rated as an aircraft tender . She was stationed at Singapore in 1924 – 25 . On 5 July 1925 she was placed in reserve at Devonport , but was briefly recommissioned in 1929 . On 22 August 1931 the ship was sold for scrap at Morecambe .