Article Summary: The USS Scorpion, a nuclear-powered U.S. Navy submarine, mysteriously sank on May 22, 1968, killing all 99 crew members. Discovered at a depth of nearly 10,000 feet, the wreckage left more questions than answers.
Key Point #1 – Theories range from mechanical failure and torpedo malfunction to a Cold War confrontation with the Soviet Union. The tragedy underscored the importance of the Navy’s SUBSAFE program, ensuring that no U.S. submarine has been lost since.
Key Point #2 – With nuclear torpedoes still onboard, concerns about contamination persist. The USS Scorpion remains one of naval history’s greatest mysteries, fueling speculation and debate to this day.
USS Scorpion: The Mystery Behind the Lost Nuclear Submarine
The USS Scorpion was a Skipjack-class nuclear-powered submarine of the United States Navy that sank on May 22nd, 1968, with 99 crew members aboard.
None survived. The cause of its sinking is uncertain and still the subject of debate. Several theories have been proposed, though a definitive answer to what exactly went wrong is still unknown.
Background and Events Leading to the Sinking
The USS Scorpion was commissioned in 1960 and was one of the fastest attack submarines in the U.S. Navy at the time.
It was designed for both anti-submarine warfare and intelligence-gathering missions. By the mid-1960s, the sub showed signs of wear and tear — ultimately, its maintenance history likely became a key factor in its loss.
In 1967, the Scorpion entered the Norfolk Naval Shipyard for an abbreviated maintenance cycle that was not in compliance with the U.S. Navy’s SUBSAFE program. SUBSAFE was established after the earlier loss of the USS Thresher in 1963 and was explicitly intended to improve submarine safety by focusing on hull integrity as well as the safety of other onboard systems.
However, the Scorpion received only limited maintenance instead of a full SUBSAFE certification due to operational demands.
While some checks improved certain aspects of the submarines, the USS Scorpion did not undergo a complete structural and system overhaul.
In early 1968, the USS Scorpion was deployed to the Mediterranean with the U.S. Sixth Fleet. The last confirmed message from the submarine was on May 21st, reporting its position approximately 50 miles south of the Azores. The vessel failed to arrive as scheduled on May 27th, prompting an extensive search.
On October 30th, after months of searching, the USS Scorpion’s wreckage was found about 400 miles southwest of the Azores, at a depth of more than 9,800 feet.
The submarine was found broken into several pieces, with its hull severely damaged.
USS Scorpion: Theories About the Cause
The exact reason for the Scorpion’s sinking remains a mystery, although a few theories have been bandied about.
One possibility postulates that a torpedo detonated inside the submarine. A faulty torpedo may have become activated inside the submarine, thanks to a fire control issue or perhaps by a hot-run, when the torpedo’s engine starts while still onboard in its firing tube.
Another theory suggests mechanical failure, possibly related to the submarine’s aging components and the incomplete SUBSAFE work.
Issues with the USS Scorpion’s seawater piping system or other structural weaknesses might have led to flooding, sinking, and eventual implosion deep underwater.
There is another theory, though somewhat less widely accepted, that suggests the USS Scorpion was fired on intentionally.
Given the Cold War tension with the Soviet Union at that time, speculation about a Soviet submarine has been raised, though it is important to note that the U.S. Navy has not officially accepted this theory.
Nuclear Weapons on Board
When it sank, the USS Scorpion was carrying two Mark 45 nuclear torpedoes, each equipped with a nuclear warhead. After the USS Scorpion’s wreckage was found, concerns were raised about potential nuclear contamination caused by the weapons.
However, after several periodic assessments of the surrounding environment, the U.S. Navy concluded that the weapons were unlikely to pose a risk given their extreme depth and probable location within the sunken submarine itself.
USS Scorpion. Image: Creative Commons.
The loss of the USS Scorpion is an enduring mystery, and one with multiple competing theories vying to explain what happened — without a conclusive answer to what exactly went wrong.
Nonetheless, the loss of the USS Scorpion highlighted the importance of the U.S. Navy’s SUBSAFE submarine maintenance and overhaul program.
Importantly, the U.S. Navy has not lost a single submarine since the tragic USS Scorpion disaster.
USS Sunfish SSN-649. Sturgeon-Class Submarine.
About the Author: Caleb Larson
Caleb Larson is an American multiformat journalist based in Berlin, Germany. His work covers the intersection of conflict and society, focusing on American foreign policy and European security. He has reported from Germany, Russia, and the United States. Most recently, he covered the war in Ukraine, reporting extensively on the war’s shifting battle lines from Donbas and writing on the war’s civilian and humanitarian toll. Previously, he worked as a Defense Reporter for POLITICO Europe. You can follow his latest work on X.
