a sled that could carry up to 15 tons of cargo, usually in the form of three Type 96 howitzers and ammunition for them. While she was at sea on 10 July 1944, I-55 was reassigned to Submarine Division 15 in the Advance Force, and on 13 July she received orders to abort her supply mission to Guam and proceed to Tinian to rescue the staff of the 1st Air Fleet there. She cast the Unpoto container adrift and headed for Tinian. At 00:40 Japan Standard Time on 13 July, she transmitted a message to 6th Fleet Headquarters estimating that she would arrive off Tinian on 15 July. The Japanese never heard from her again. At 21:20 on 13 July 1944, an American patrol plane spotted a Japanese submarine submerging in the Philippine Sea off Saipan′s Rorogattan Point. The submarine′s position was reported to a United States Navy hunter-killer group, which detached the high-speed transport and destroyer escort to hunt it down. The two ships arrived at the submarine′s last reported position at 00:22 on 14 July 1944 and began their search. Seven hours later, William C. Miller picked up a sound contact at a range of and approached the contact at . She began her attack at 07:26 by dropping a pattern of 13 depth charges, followed by a second pattern of 13 depth charges at 07:52. At 0804, her crew observed pieces of wood rising to the surface about ahead on William C. Miller′s starboard bow, then heard a heavy underwater explosion at 08:05 that shook the ship, followed by bubbles rising to the surface that made the water appear to boil. William C. Miller dropped a third pattern of 13 depth charges at 0806, sinking the submarine. An oil slick and debris covered the surface, and William C. Miller steamed into the slick and recovered pieces of cork insulating material, splintered wooden decking, and a seaman's cap at . It remains a matter of dispute as to whether William C. Miller sank I-55 or the submarine . The destroyer escorts and also have received credit for sinking I-55 in an antisubmarine action on 28 July 1944. On 15 July 1944, the Imperial Japanese Navy declared I-55 to be presumed lost with all 112 hands off Tinian. She was stricken from the Navy list on 10 October 1944. Notes References External links Tabular movements of submarine I-55 warsailors.com