 Now the flagship of the Second Carrier Division under Rear Admiral Munetaka Sakamaki, Hiyō and her sister Junyō departed Yokosuka on 7 June en route for Truk. Later that evening, the ship was torpedoed by the submarine USS Trigger off Miyakejima. Hits in the starboard bow and boiler room knocked out all power, but she managed to return to Japan the following day after restoring power. Hiyō's fighters were flown to Truk by 15 July and assigned to the light carrier Ryūhō. The ship was under repair at Yokosuka until 15 September. On 1 November, Hiyō's air group was reconstituted with 24 Zeros, 18 D3As and 9 B5Ns and the ship departed Japan for Singapore on 24 November. She arrived on 3 December and was almost immediately assigned duties as an aircraft ferry. On 9 December, Hiyō left Singapore en route for Truk with several deliveries on the way. The ship arrived there on 22 December and disembarked her own air group before proceeding on to Saipan to deliver more aircraft. The air group was transferred to Kavieng and later Rabaul to provide air cover for Japanese operations there.
