was the name ship of her class of two aircraft carriers of the Imperial Japanese Navy (IJN). Originally planned as the ocean liner in 1939, she was purchased by the Navy Ministry in 1941 for conversion to an aircraft carrier. Completed shortly after the Battle of Midway in June 1942, she participated in the Guadalcanal campaign, but missed the Battle of the Santa Cruz Islands in October because of an electrical generator fire. The carrier's aircraft were disembarked several times and used from land bases in battles in the South West Pacific. Hiyō was torpedoed in mid-1943 and spent three months under repair. She spent most of the next six months training and ferrying aircraft before returning to combat. She was sunk by a gasoline-vapour explosion caused by an American torpedo hit during the Battle of the Philippine Sea on 20 June 1944 with the loss of 247 officers and ratings, about a fifth of her complement. Design and description The ship was ordered as the fast luxury passenger liner Izumo Maru by Nippon Yusen Kaisha (Japan Mail Steamship Company) in late 1938. In exchange for a 60 per cent subsidy of her building costs by the Navy Ministry, she was designed to be converted to an aircraft carrier in the event of war. The designs of Izumo Maru and her sister ship Kashiwara Maru were based on the German ocean liner , although they were only about half that ship's size at . If completed as designed, they would have been the largest ocean liners in Japan. The ships were designed to carry a total of 890 passengers; 220 first class, 120 second class and 550 third class. After her conversion, Hiyō had a length of overall. She had a beam of and a draught of . She displaced at standard load. Her crew ranged from 1,187 to 1,224 officers and ratings. The ship was fitted with a pair of Mitsubishi-Curtis geared steam turbine sets with a total of , each driving one propeller, using steam provided by six Kawasaki-LaMont boilers. Hiyō had a designed speed of and slightly exceeded that during sea trials. The ship carried enough fuel oil to give her a range of at . Flight deck arrangements Hiyōs flight deck was long and had a maximum width of . The ship was designed with two superimposed hangars, each approximately long, wide and high. Each hangar