USS INDIANAPOLIS: The Shark Attack That Followed a Torpedo (1945)

Category|Deep Sea & Underwater

Year|1945

Credibility Grade|CLASS CORROBORATED

Last updated: 19 Apr 2026

Quick Summary

On 30 July 1945, the heavy cruiser USS Indianapolis (CA-35) was torpedoed by the Japanese submarine I-58 in the Philippine Sea, sinking in just 12 minutes. Of the 1,195 crew members aboard, approximately 300 went down with the ship. The remaining 890 men were cast into the open Pacific with minimal supplies—no distress signal was received, and no one came looking for them. Over the next four days and five nights, the survivors endured exposure, dehydration, saltwater poisoning, hallucinations, and what is now considered the deadliest mass shark attack in recorded history. By the time rescue arrived on 2 August, only 316 men remained alive. The disaster was compounded by a series of catastrophic communication failures within the U.S. Navy, and the subsequent court-martial of Captain Charles B. McVay III became one of the most controversial military proceedings of the 20th century.

Key Facts

CountryPhilippine Sea — approximately 12°02′N, 134°48′E; midway between Guam and Leyte Gulf, Philippines

Year30 July 1945 (torpedoed at 00:15); rescued 2 August 1945

TypeWartime Disaster / Deadliest Shark Attack in History / Naval Communication Failure

Overview

The USS Indianapolis occupies a singular place in both military and natural history. It is
simultaneously the story of a warship that changed the course of World War II by delivering the
components of the first nuclear weapon used in combat, and the story of the worst shark attack
ever inflicted on human beings.
The Indianapolis was a Portland-class heavy cruiser that served as the flagship of Admiral
Raymond Spruance’s Fifth Fleet from 1943 to 1945, participating in major engagements across
the Central Pacific including the Battles of the Philippine Sea and Iwo Jima. In March 1945, the
ship was severely damaged by a kamikaze strike off Okinawa and sent to California for repairs.
It was during this repair period that the Navy selected Indianapolis for one of the most
consequential missions of the war: the secret delivery of enriched uranium and other
components for the atomic bomb to the island of Tinian.
The ship completed the delivery in record time, traveling from San Francisco to Tinian in just ten
days. What no one aboard knew was that the cargo they had carried would, eleven days later,
level the city of Hiroshima and effectively end the war in the Pacific.
But for the crew of the Indianapolis, the war would end in a different way entirely.

Listen to Case File

~9 min

Timeline

16 July 1945

Indianapolis departs San Francisco carrying secret atomic bomb components under maximum security.

26 July 1945

Arrives at Tinian Island; cargo delivered to scientists assembling “Little Boy.”

28 July 1945

Departs Guam for Leyte Gulf, Philippines, unescorted. Captain McVay requests but is denied a destroyer escort. The Navy fails to warn him of known Japanese submarine activity in the area.

30 July 1945 — 00:15

Two torpedoes from submarine I-58, commanded by Mochitsura Hashimoto, strike the Indianapolis. The first blows off the bow; the second hits amidships near the powder magazine, splitting the ship to the keel. All power is lost instantly.

00:27

Indianapolis sinks. Approximately 300 men go down with the ship. ~890 survivors enter the water, many injured, burned, or covered in fuel oil. Distress signals are sent but not received or acted upon.

31 July 1945

Indianapolis fails to arrive at Leyte Gulf as scheduled. No search is initiated. Three separate shore stations received distress signals but failed to act: one commander was drunk, another had ordered his men not to disturb him, and a third believed it was a Japanese trap.

30 July – 2 August

For four days and five nights, survivors float in groups in the open Pacific. They face: dehydration, saltwater poisoning (hypernatremia), hypothermia at night, severe sunburn by day, hallucinations and psychosis, shark attacks (primarily oceanic whitetips), and violence between delusional survivors. The dead are cut loose and pushed away to avoid attracting more sharks.

2 August 1945 — 11:00

Lieutenant Wilbur Gwinn, flying a routine patrol in a PV-1 Ventura, spots a large oil slick. Investigating, he discovers hundreds of men floating in the water. He radios the sighting.

2 August — afternoon

A PBY Catalina flying boat, piloted by Lieutenant Adrian Marks, lands on the open sea despite 12-foot swells to begin pulling survivors from the water. USS Cecil Doyle (DD-368) arrives and begins coordinated rescue.

2–3 August 1945

Seven ships participate in the rescue operation. 316 survivors are recovered. The rest—879 men—are dead.

6 August 1945

The atomic bomb “Little Boy,” assembled using the components delivered by Indianapolis, is dropped on Hiroshima.

November 1945

Captain McVay is court-martialed on charges of “hazarding his ship by failing to zigzag” and “failing to order abandon ship.” He is convicted of the former despite testimony from Commander Hashimoto himself that zigzagging would not have prevented the attack.

1968

Captain McVay dies by suicide at age 70, reportedly found holding a toy sailor given to him by his father as a boy.

2000–2001

U.S. Congress passes a resolution exonerating McVay. The Navy places a memorandum in his file clearing him of all wrongdoing.

August 2017

A research expedition funded by Paul Allen locates the wreckage of Indianapolis at a depth of 5,500 meters (18,000 feet) on the floor of the Philippine Sea.

Witness Accounts

Survivor Loel Dean Cox described the shark attacks to the BBC: every now and then, a shark
would come straight up and take a sailor straight down. The man next to him was taken—just
screaming, yelling, or getting bit. Cox said the sharks were drawn to blood and to the
movements of the struggling men.
Harlan Twible, a young ensign who organized “shark watches” among his group, recalled that
the sharks generally stayed away from larger clusters of men but picked off individuals who
drifted from the group. He described cutting the dead from debris to push them away, so that
the living would not have to see what the sharks did to the corpses.
Harold Bray, the last living survivor, said decades later that the experience was the worst thing
he had ever known. He confirmed that the sharks took young sailors from his group and said he
could never speak fully of what he saw.
Multiple survivors described the terror of the nights as worse than the days. The sharks were
more active in darkness. Men could hear splashing and screaming but could see nothing. By the
third and fourth day, hallucinations began. Delirious men imagined they saw land, hotels, or
enemy ships. Some attacked their own companions. Others swam away from the group toward
phantom islands and were never seen again.

▶ CINEMATIC SECTIONNarrative Reconstruction

It is just after midnight on 30 July 1945. The Philippine Sea is calm, the sky overcast. The
Indianapolis is making 17 knots, alone and unescorted, cutting through moderate swells. Below
decks, most of the 1,195 men are asleep. They do not know that eleven days from now, a bomb
assembled from the cargo they delivered will end the bloodiest war in human history. They do
not know that six hundred miles to the north, a Japanese submarine is tracking the moonlight on
their hull.\nAt 00:15, two torpedoes strike. The first rips the bow apart. The second detonates near the
ammunition magazine and the ship’s fuel bunkers. A column of flame erupts amidships. The
explosion is so violent that the ship is split to the keel. Power fails instantly. The Indianapolis
begins to roll.\nTwelve minutes. That is all the time there is. Men scramble through dark, flooding corridors.\nSome never make it to the deck. Some jump into water already burning with fuel. Some are
sucked into the vortex as the ship goes under, bow first, at 00:27.\nAnd then silence. Nine hundred men floating in the Pacific, many without life rafts, clinging to
debris and each other. No one on shore knows they are there. No one is coming.\nThe first day is survivable. The men organize into groups. They share the few life vests and
rafts. Officers take charge. They wait for rescue. Rescue does not come.\nThe sharks arrive with the first light. Oceanic whitetips—open-ocean predators with rounded
white-tipped fins and a reputation for bold, investigative approaches to floating objects. They
circle. They bump. Then they begin to feed. First the dead. Then the wounded. Then anyone
who drifts too far from the group.\nBy the second day, thirst is unbearable. The tropical sun burns exposed skin through the fuel
oil. Men begin to drink seawater, which accelerates dehydration and triggers hallucinations.\nFights break out. Some men drown their own companions, convinced they are enemy agents.\nBy the third night, the groups are smaller. The sharks are constant. The living push the dead
away and form tighter circles, kicking at anything that approaches from below. The water is
dark. The screams are constant. No one sleeps.\nOn the morning of 2 August, Lieutenant Gwinn spots an oil slick from his patrol plane and
changes course to investigate. He sees hundreds of tiny dots in the water. It takes him a
moment to understand what he is seeing. Then he radios the most important message of these
men’s lives.\nBy nightfall, the first ships arrive. Men weep. Some are too far gone to be saved. 316 are pulled
from the water alive. The other 879 are already gone—taken by the ship, by the sea, by the sun,
by their own minds, or by the sharks that circled them for four days and five nights.

Evidence

**Physical Evidence**
Wreckage located at 5,500 meters depth in August 2017 by the Paul Allen
expedition using the research vessel R/V Petrel. The wreck confirmed the violence of the
torpedo strikes and the rapid nature of the sinking.

**Documentary Evidence**
Extensive U.S. Navy records, court-martial transcripts, after-action
reports, and communication logs. Reuters and Associated Press dispatches from August 1945.
Declassified intelligence showing the Navy knew of Japanese submarine activity in
Indianapolis’s path.

**Testimonial Evidence**
Hundreds of survivor accounts collected over 80 years. Key testimonies
include Harlan Twible, Loel Dean Cox, Edgar Harrell, Harold Bray, and many others.
Commander Hashimoto’s own testimony at McVay’s court-martial.

**Scientific Evidence**
Discovery Channel’s 2007 documentary “Ocean of Fear” employed shark
attack researcher George Burgess to analyze the predation patterns. Oceanic whitetip sharks
confirmed as the primary species involved, consistent with their known behavior of investigating
shipwrecks and floating debris in open ocean.

**Cultural Evidence**
The 1975 film Jaws featured a famous monologue by the character Quint
(Robert Shaw) describing the Indianapolis sinking, which brought the incident to global public
awareness for the first time.