The Record
Heavy cruiser. Delivered components of the Hiroshima bomb to Tinian, then torpedoed four days later by Japanese submarine I-58 in the Philippine Sea on 30 July 1945. Of 890 men who went into the water, only 316 were alive four days later when the silence was finally noticed; the sharks had taken an estimated 150 to 300 of the rest. Captain Charles McVay became the only U.S. commander court-martialed for losing his ship in combat, and Congress exonerated him posthumously in 2000.
The Vessel
USS Indianapolis (CA-35) was a Portland-class heavy cruiser of the United States Navy, commissioned at the Philadelphia Navy Yard on 15 November 1932. She was 185 metres long, 9,950 tons standard displacement, with nine 8-inch guns in three triple turrets and a designed speed of 32 knots on four shafts. Her class had been designed to the limits of the Washington Naval Treaty as the American answer to the Japanese Myōkō class, sharing a hull form with the preceding Northampton-class.
She served as the flagship of Scouting Force 1 through the 1930s and as the Pacific Fleet's flagship under Admiral Raymond Spruance from August 1943. By July 1945 she had ten Pacific War battle stars, had taken a kamikaze hit at Okinawa on 31 March that put her into San Francisco for repairs, and had emerged from the Mare Island Naval Shipyard refit on 14 July 1945. Her master was Captain Charles Butler McVay III, a 46-year-old career officer, son of an admiral, holder of the Silver Star from Solomons action two years earlier.
Her assignment on 16 July 1945 was a secret: to transport from Hunter's Point, California, to Tinian, Marianas, the U-235 enriched uranium core and the casing components of Little Boy, the atomic bomb to be dropped on Hiroshima three weeks later. The cargo was delivered on 26 July. Her delivery was the last significant operational act of her career.
The Voyage
She departed Tinian on 28 July 1945 for Guam, and on 30 July resumed her independent passage north-westward toward Leyte, in the Philippines, to join Admiral Oldendorf's training group for the forthcoming invasion of the Japanese home islands. She was routed along the Peddie Route, a standard unescorted transit route for heavy units in the Philippine Sea. She had no escort because the Pacific Fleet by late July 1945 no longer considered Japanese submarine threats serious enough to warrant destroyer attachment for a single cruiser.
The Japanese fleet submarine I-58, commanded by Lieutenant Commander Mochitsura Hashimoto, was on patrol in the Peddie Route approaches. Hashimoto had received a pre-war generation of submariner training, had commanded submarines since 1942, and had already sunk three Allied ships in this patrol. He sighted Indianapolis at 23:00 on 29 July, closed, manoeuvred to an ideal firing position on her port bow, and at 00:14 on 30 July 1945 launched a full salvo of six Type 95 torpedoes from a range of 1,500 metres. Two struck.
The first struck her starboard bow at 00:15, detonating a forward magazine and blowing the bow off the ship. The second struck amidships at frame 58, entering her starboard side below the waterline. She listed to starboard, flooded forward, and settled by the bow. Twelve minutes after the first torpedo strike, at 00:27, she rolled onto her starboard side and sank stern last. 300 men had died in the explosions and sinking. 880 had entered the water alive.
The Disaster
The distress message that McVay's chief radio officer had ordered transmitted in the moments before the sinking had gone out, but was not received. The Navy's communications procedures for unescorted ships in transit were under-developed; the Indianapolis's arrival at Leyte was not logged as overdue, and her non-arrival was not noticed. She had simply vanished.
The 880 men in the water entered an environment for which they had almost no preparation. Many had life jackets; most had no life rafts. The water temperature was 28 degrees Celsius and the weather fair, which meant that drowning was slower than it would have been in the North Atlantic but that exposure would take longer to act. The principal killers through the following days were dehydration from saltwater ingestion, drowning from exhaustion, and oceanic whitetip shark attacks.
Over four days an estimated 150 to 300 men died from shark attack, the largest known incidence of shark-inflicted deaths in human history; most historians have settled on the figure of approximately 200, from an initial survivor population of 880 reduced to 316 by the time rescue arrived on the morning of 2 August. The rescue itself was by accident: a patrol plane on a routine Japanese-submarine search sighted the men at 11:00 on 2 August, 83 hours after the sinking. The pilot, Lieutenant Wilbur Gwinn, reported survivors and diverted the nearest rescue ship.
Of the 1,195 aboard at Tinian's departure, 316 survived. 879 died. The shark figure of 150-300 is, as every historian of the event has noted, the best documented mass-shark-attack toll in any identified location.
The Legacy
The court-martial of Captain McVay in December 1945 remains the most controversial single prosecution in American naval history. McVay was charged with "hazarding the ship" by failing to zigzag; Mochitsura Hashimoto was flown to Washington from Japan to testify and stated on the stand that zigzagging would have made no difference to his attack. The court found McVay guilty. He was the only captain in the history of the United States Navy to be court-martialled for losing a ship in combat. Admiral Nimitz remitted the sentence immediately; McVay returned to service, retired in 1949 as a Rear Admiral, and killed himself in 1968, a toy sailor from his boyhood still in his hand.
The surviving crew campaigned for McVay's exoneration for five decades. On 30 October 2000 Congress passed, and President Clinton signed, a joint resolution exonerating McVay and directing the Navy to modify his service record to reflect that he had been "not at fault" for the loss of Indianapolis. The resolution was supported by every living surviving crew member and by Hashimoto, who had written to the Senate ten years earlier urging McVay's exoneration and who died shortly after the resolution was adopted.
The wreck of Indianapolis was located on 19 August 2017 by an expedition sponsored by Paul Allen's Research Vessel Petrel, at a depth of 5,500 metres in the Philippine Sea. She lies broken into two sections, her bow section missing forward of the bridge, upright, relatively intact for a ship lost at her depth. The location is a protected United States war grave and has not been disturbed.
Her name is preserved on a memorial on the Canal Walk in Indianapolis, Indiana, listing her 879 dead. Survivor reunions continued until the last reunion at Indianapolis in 2017, when the last four aboard were present. The last survivor, Harold Bray, died in January 2023, and with him the living memory of the longest survival in open water in modern maritime history.