USS Indianapolis: Secret Mission, Sinking & Survival

The Quiz Question

Which US Navy heavy cruiser, having just delivered components for the atomic bomb to Tinian Island, was torpedoed by a Japanese submarine in July 1945, leaving survivors adrift for days and suffering some of the worst shark attacks in recorded history?

A. USS Indianapolis
B. USS Houston
C. USS Franklin
D. USS Bunker Hill

The answer is A. USS Indianapolis. Here is the full story.

In the final weeks of the Second World War, with Allied victory almost certain, 1,195 American sailors sailed into the Philippine Sea aboard a heavy cruiser carrying one of the most important secrets in history. Within days, all but 316 of them would be dead — and the United States Navy wouldn't even know the ship was missing. The story of USS Indianapolis is one of extraordinary bravery, catastrophic institutional failure, and suffering almost beyond imagination.

A Proud Ship With a Distinguished Record

USS Indianapolis (CA-35) was a Portland-class heavy cruiser commissioned in November 1932. She was fast, powerful, and well-regarded — the kind of ship officers fought to serve aboard. For much of the Pacific War, she carried Admiral Raymond Spruance's flag as the flagship of the 5th Fleet, placing her at the heart of America's island-hopping campaign.

She earned her battle scars honestly. Indianapolis participated in major operations at Tarawa, the Marshall Islands, the Marianas, Iwo Jima, and Okinawa. On 31 March 1945, a kamikaze strike off Okinawa killed nine of her crew and caused serious enough damage to send her back to the Mare Island Naval Shipyard in San Francisco for repairs. She emerged from those repairs in July 1945 with a crew of roughly 1,195 men — a mix of hardened veterans and sailors newly assigned to the ship, many of whom had never served together before.

The Secret Mission: Delivering the Bomb

On 16 July 1945 — the very same day that the United States detonated the world's first nuclear device at the Trinity test site in New Mexico — Indianapolis quietly departed San Francisco on a mission her crew knew almost nothing about. She carried components of "Little Boy," the uranium bomb being prepared for use against Japan: enriched uranium-235, a uranium target insert, and associated assembly parts, packed into specially constructed canisters and a wooden crate bolted to the hangar deck.

The cargo was so sensitive that Captain Charles Butler McVay III was given only the barest details about what he was carrying. He knew it was important. He knew it was secret. He did not know it would help end the war. Indianapolis made the approximately 5,000-mile run to Tinian Island in a record ten days, arriving on 26 July 1945. The components she delivered were loaded into the Boeing B-29 Enola Gay and dropped on Hiroshima on 6 August 1945.

Having completed her mission, Indianapolis received orders to proceed to Guam and then to Leyte Gulf in the Philippines, where she was to join Task Force 95 and begin training for the planned invasion of Japan. She sailed unescorted — a routine arrangement at that stage of the war, when Japanese surface power had been effectively destroyed. But the seas were not free of danger.

Midnight Attack: Japanese Submarine I-58 Strikes

Commander Mochitsura Hashimoto commanded the Japanese submarine I-58, one of the Imperial Navy's more capable late-war boats. On the night of 29–30 July 1945, I-58 was patrolling the Philippine Sea when her crew spotted the silhouette of a large vessel moving without escort. Hashimoto had his crew at action stations within minutes.

Just after midnight on 30 July 1945, I-58 fired six Type 95 torpedoes. At least two struck Indianapolis amidships in rapid succession. The first detonation obliterated the bow area and ignited the aviation fuel stores. The second destroyed the midship area near the powder magazines. The combination was catastrophic. Indianapolis sank in approximately twelve minutes — so fast that no coherent distress signal was transmitted, no proper lifeboat launch was completed, and many men below decks had no chance at all. Around 300 men went down with the ship. Roughly 900 made it into the water — many without life jackets, many already wounded, all of them plunged suddenly into the dark Philippine Sea with no rescue in sight.

Days in the Water: Thirst, Madness, and the Sharks

The survivors scattered across miles of open ocean in the darkness. Some found floater nets, kapok life jackets, or small rafts. Others had nothing but their own buoyancy. Groups formed in the night and called out to each other, but the sea was vast and communications were impossible. Some groups never located the others at all.

The oceanic whitetip shark, one of the most aggressive open-water species, was drawn almost immediately to the blood and frantic movement in the water. Attacks began in the early hours and continued throughout the days that followed — individual men taken at the edges of groups, sometimes in terrifying feeding frenzies that survivors described as the ocean itself turning violent. The precise number of men killed by sharks remains unknown and is a matter of ongoing historical debate, but the attacks were sustained, repeated, and witnessed by hundreds of survivors.

By the second day, thirst had become as deadly as the sea itself. Men began drinking seawater. This accelerated dehydration dramatically, driving victims into a cycle of increasing salt poisoning, paranoid delusions, and death. Hallucinations set in across the groups: men became convinced they could see land, a rescue ship, or a hotel just below the surface. Some attacked their shipmates, believing them to be Japanese. Others simply swam away from the group and were never seen again. The psychological toll was devastating and total.

Of the roughly 900 men who entered the water, the combination of exposure, dehydration, salt poisoning, injuries sustained in the sinking, and shark attacks reduced that number to 316 by the time rescue arrived.

Four Days Ignored: The Navy's Catastrophic Failure

Here is where the story becomes a scandal as well as a tragedy. Indianapolis was due at Leyte Gulf on 31 July 1945. She did not arrive. No search was ordered. Lieutenant Commander George Watkins, the port director at Leyte, noted the non-arrival but assumed the ship had been diverted — a not uncommon occurrence. The assumption was wrong, and the consequences were fatal.

A tangle of administrative failures, conflicting routing instructions, and the simple assumption that no news meant good news left nearly a thousand men dying in the Philippine Sea while the Navy went about its business. Ships were not always reported upon arrival; the system had gaps that had never been exposed so brutally before. For nearly four days, no one in the United States Navy officially knew that Indianapolis was missing.

The survivors were found by pure chance. On 2 August 1945, Lieutenant Wilbur "Chuck" Gwinn was flying a PV-1 Ventura patrol bomber on a routine anti-submarine patrol when he spotted an oil slick and then, impossibly, men floating in the open ocean. He immediately radioed for help. Lieutenant Adrian Marks flew a PBY Catalina to the scene and, in a decision that broke naval regulations but saved lives, landed his aircraft on open ocean swells to begin pulling men aboard — packing them onto the wings and fuselage when the cabin was full. The destroyer USS Cecil J. Doyle arrived at 23:00 on 2 August and began the main rescue operation. Other vessels followed through the night and into the following days.

Captain McVay: The Court Martial That Divided America

In December 1945, Captain Charles Butler McVay III was court-martialled — the only US Navy captain to face such proceedings for losing his ship in combat during the Second World War. The charge was "hazarding his vessel by failing to zigzag," a manoeuvre intended to make a ship harder to target by submarine. McVay was convicted, though the Navy's own evidence and testimony made clear that zigzagging would likely not have prevented Hashimoto's attack under the conditions that night.

In one of the more remarkable and controversial decisions of the post-war period, Commander Hashimoto himself was brought to Washington to testify against McVay. He told the court that he could have sunk Indianapolis whether she was zigzagging or not. McVay was convicted regardless.

The punishment followed McVay for the rest of his life. He received hate mail from the families of the dead — sometimes from schoolchildren who had been told about the disaster — blaming him for their losses. He carried that weight for over two decades. In November 1968, Charles McVay took his own life at his home in Connecticut. He was holding a toy sailor in his hand when he was found.

In October 2000, the United States Congress passed a resolution stating that McVay's record should reflect that he was exonerated for the loss of Indianapolis. The US Navy subsequently amended his official record. It was long overdue, and it came too late for the man himself.

The Survivors: Men Who Carried the Ocean Home

Dr. Lewis Haynes, the ship's chief medical officer, is one of the great human stories of the ordeal. Without a single piece of medical equipment, he moved through the water for days, keeping men calm, stopping them from drinking seawater, talking to the dying. His efforts are credited with saving a number of lives that might otherwise have been lost to despair alone.

Giles McCoy, a Marine private and one of the youngest survivors, became one of the most prominent voices for the crew's story in the decades that followed. Edgar Harrell, a Marine corporal who endured more than four days in the water, later wrote a memoir and spoke widely about the role of his Christian faith in sustaining him through the ordeal. Many others never spoke of it at all — PTSD was unrecognised and untreated in 1945, and survivor guilt ran deep and silent through the lives of men who came home when so many did not.

The Indianapolis Survivors Organisation held annual reunions in Indianapolis, Indiana — the city that shared the ship's name and embraced its legacy — for decades after the war, until the advancing age of the last survivors made continuation impossible.

Legacy: Why the Indianapolis Story Still Matters

The disaster prompted significant reform in US Navy ship-tracking and reporting procedures. The specific failures that allowed Indianapolis to go missing for nearly four days — poor arrival reporting, ambiguous routing orders, and a culture of assumption over verification — were formally examined and addressed in the aftermath.

The story entered mainstream popular culture in 1975, when actor Robert Shaw delivered a haunting monologue about the Indianapolis sinking in the film Jaws. Shaw's character, Quint, is fictional, but the monologue was developed with input from actual survivors and brought the tragedy to millions of people who had never heard of it. It remains one of the most powerful pieces of film dialogue about the Second World War.

On 19 August 2017, a research team funded by Microsoft co-founder Paul Allen located the wreck of USS Indianapolis lying approximately 5,500 metres below the surface of the Philippine Sea. The discovery renewed global interest in the ship's story and provided a measure of closure for surviving family members.

In more recent years, the state of Indiana and the city of Indianapolis have continued to honour the ship and her crew with memorials and civic recognition. The connection between a Midwestern city and a warship lost in a distant ocean speaks to something enduring: the way a community absorbs its grief and refuses to let the dead be forgotten.

The story of USS Indianapolis is, at its heart, a story about two kinds of failure — the failure of an enemy to be merciful, which is war, and the failure of an institution to protect its own people, which is something else entirely. In the final weeks of a war already won in everything but paperwork, 880 American sailors died in the Philippine Sea because the Navy did not notice they were missing. Their story deserves to be told, and retold, until the lessons it carries are truly learned.

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