Hiyō was a Junyo-class aircraft carrier of the Imperial Japanese Navy. Begun as an 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 in October and missed the Battle of the Santa Cruz Islands later that month because of an electrical generator fire. Her aircraft were disembarked several times and used from land bases in a number of 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 vapor explosion caused by an American torpedo hit during the Battle of the Philippine Sea in mid-1944.