Taihō was formally commissioned on 7 March 1944. After several weeks of service trials in Japan's Inland Sea, she was deployed to Singapore, arriving there on 5 April. Taihō was then moved to Lingga Roads, a naval anchorage off Sumatra, where she joined veteran carriers and in the First Carrier Division, First Mobile Force. All three carriers engaged in working up new air groups by practicing launch and recovery operations and acting as targets for mock aerial attacks staged from Singapore airfields by their own planes. On 15 April, Vice-Admiral Jisaburo Ozawa officially transferred his flag from Shōkaku to Taihō to take advantage of the carrier's extensive command facilities. Shortly thereafter, the First Mobile Force departed Lingga and arrived on 14 May at Tawi-Tawi off Borneo, where the fleet could directly refuel with unrefined Tarakan Island crude oil and await execution of the planned Kantai Kessen ("decisive battle") known as Operation A-GO. When American carrier strikes against the Marianas indicated an invasion of Saipan was imminent, the Japanese Combined Fleet staff initiated Operation A-GO on 11 June. Taihō and the rest of Ozawa's First Mobile Force departed Tawi-Tawi on 13 June, threading their way through the Philippine Islands and setting course for Saipan to attack American carrier forces operating in the vicinity. Fate On 19 June 1944, Taihō was one of nine Japanese aircraft carriers involved in the Battle of the Philippine Sea. At 07:45 she turned into the wind to launch her contribution (16 Zeros, 17 "Judy" dive bombers and 9 "Jill" torpedo bombers) to Ozawa's second attack wave. As Taihōs planes circled overhead to form up, American submarine , which had spotted Ozawa's carriers earlier that morning, reached an ideal attack position and fired a spread of six torpedoes at the carrier. One of Taihōs strike pilots, Warrant Officer Sakio Komatsu, saw the torpedo wakes, broke formation and deliberately dived his plane into the path of one torpedo; the weapon detonated short of its target and four of the remaining five missed. The sixth torpedo, however, found its mark and the resulting explosion holed the carrier's hull on the starboard side, just ahead of the island. The impact also fractured the aviation fuel tanks and jammed the forward elevator between the flight deck and upper hangar deck. With the ship down 1.5 m (5 ft) by the bows due to flooding, the forward elevator pit filled with a