http://en.wikipedia.org/wiki/USS_Indianapolis_(CA-35)
Wikipedia
USS Indianapolis (CA-35)
USS Indianapolis (CA-35) was a Portland-class cruiser of the United States Navy. She holds a place in history due to the circumstances of her sinking, which led to the greatest single loss of life at sea in the history of the U.S. Navy. On 30 July 1945, shortly after delivering critical parts for the first atomic bomb to be used in combat to the United States air base at Tinian, the ship was torpedoed by the Imperial Japanese Navy submarine I-58, sinking in 12 minutes. Of 1,196 crewmen aboard, approximately 300 went down with the ship.
The remaining crew of 880 men faced exposure, dehydration and shark attacks as they waited for assistance while floating with few lifeboats and almost no food or water. The Navy learned of the sinking when survivors were spotted four days later by the crew of a PV-1 Ventura on routine patrol. Only 316 sailors survived. Indianapolis was the last major U.S. Navy ship sunk by enemy action in World War II.
Loss
After major repairs and an overhaul, Indianapolis received orders to proceed to Tinian island, carrying parts and the enriched uranium for the atomic bomb Little Boy, which would later be dropped on Hiroshima.
Navy failure to learn of the sinking
Operations plotting boards were kept at the Headquarters of Commander Marianas on Guam and of the Commander Philippine Sea Frontier on Leyte. On these boards, the positions of all vessels of which the headquarters was concerned were plotted. However, for ships as large as the Indianapolis, it was assumed that they would reach their destinations on time, unless reported otherwise. Therefore, their positions were based on predictions, and not on reports. On 31 July, when she should have arrived at Leyte, Indianapolis was removed from the board in the headquarters of Commander Marianas. She was also recorded as having arrived at Leyte by the headquarters of Commander Philippine Sea Frontier. Lieutenant Stuart B. Gibson, the Operations Officer under the Port Director, Tacloban, was the officer responsible for tracking the movements of Indianapolis. The non-arrival of that vessel on schedule was known at once to Lieutenant Gibson who failed to investigate the matter and made no immediate report of the fact to his superiors.
The Indianapolis sent distress calls before sinking. Three stations received the signals; however, none acted upon the call. One commander was drunk, another had ordered his men not to disturb him and a third thought it was a Japanese prank. For a long time the Navy denied that a distress call had been sent. The receipt of the call came to light only after the release of declassified records.
Immediately prior to the attack, the seas had been moderate, the visibility fluctuating but poor in general, and Indianapolis had been steaming at 17 kn (20 mph; 31 km/h). When the ship did not reach Leyte on the 31st, as scheduled, no report was made that she was overdue. This omission was due to a misunderstanding of the Movement Report System. Captain Charles Butler McVay III, who had commanded Indianapolis since November 1944, survived the sinking, and was with those rescued days later. In November 1945, he was court-martialed and convicted of "hazarding his ship by failing to zigzag." Several things about the court-martial were controversial. There was evidence that the Navy itself had placed the ship in harm's way, in that McVay's orders were to "zigzag at his discretion, weather permitting." Further, Mochitsura Hashimoto, commander of I-58, testified that zigzagging would have made no difference.
