submarine tender . On 9 January 1944, she got underway from Truk bound for Rabaul, which she reached on 13 January 1944. She departed Rabaul on 17 January 1944 and proceeded to Gali, New Guinea. She arrived there on 22 January 1944, picked up passengers, and departed the same day for Rabaul, where she arrived on 26 January 1944. On 30 January, she departed Rabaul to make a supply run to the Japanese garrison on Buka Island, carrying rubber supply containers on her deck. Loss On 1 February 1944, the U.S. Navy destroyers and detected I-171 on the surface on radar west of Buka Island at a range of . I-171 submerged, but the two destroyers gained sonar contact on her and both depth charged her, sinking her at . The Japanese last heard from I-171 on 1 February 1944. They attempted to contact her unsuccessfully several times on 3 February 1944, and concern for her grew when she did not return to Rabaul as scheduled at 18:00 on 5 February 1944. On 12 March 1944, the Japanese declared her to be presumed lost off Buka Island with the loss of all 91 men on board. On 14 March 1944, U.S. Navy codebreakers intercepted and decrypted a message from the commander of the Southeastern Area Submarine Force which read, "I-171 departed Rabaul January 30, arrived Buka Feb. 2 [blurred number might be 1 or might be 2]. Completed unloading men and cargo and (continued on special transportation duties). Has not been heard from since February 1. According to report of naval force at Buka, an enemy destroyer was (sighted) to west of Buka that date. It is assumed that Captain and all hands died in battle. -----." I-171 was stricken from the Navy list on 30 April 1944. Notes References 1934 ships Ships built by Kawasaki Heavy Industries World War II submarines of Japan Kaidai-class submarines Attack on Pearl Harbor Ships of the Battle of Midway Ships of the Aleutian Islands campaign Maritime incidents in February 1944 World War II shipwrecks in the Pacific Ocean Japanese submarines lost during World War II Submarines sunk by United States warships Ships lost with all hands