By James Donahue

There have only been two U.S. submarines lost at sea with all hands since the end of World War II. These were the USS Thresher in 1963 with the loss of 129 lives, and the USS Scorpion in 1968 with 99 crewmen. Both were nuclear submarines commissioned in 1960 and 1961, within months of each other.

The Thresher was the first to go, and some believe political budget decisions surrounding the disaster may have played a role in the loss of Scorpion. America was locked in the midst of the Cold War with Russia in those years and there was a race between the two “superpowers” for submarine naval superiority. It was not then known that Russia was winning the race.

After the Thresher disaster, the Navy launched a “Submarine Safety Program,” a massive and costly retrofit of submarine safety systems. But the program was keeping the nation’s submarine fleet tied-up in dry dock for months at a time. There developed great political embarrassment about our inability to keep our submarine fleet at sea. Thus the Scorpion got what was described as a superficial “overhaul,” the planned revamping slashed to no more than emergency repairs so the ship could return to sea duty.

Consequently, Scorpion did not receive a new central valve control system, a fix for the problem believed to have caused the Thresher to sink. In the event of a shutdown of the submarine’s nuclear reactor, it was believed the Emergency Main Ballast Tank blow system also failed.

It is interesting to note that two crew members. EM2 Daniel Rogers and Radioman Chief Daniel Pettey took drastic measures to be released from duty aboard Scorpion. They cited bad morale problems but they may have had a premonition. Rogers sought and was granted disqualification from submarine duty. Pettey was so anxious to get off the sub he tried to transfer into the U.S. Army and was released from Scorpion just weeks before Scorpion was lost.

On her final duty, Scorpion, Commander Francis A. Slattery at the helm, called at Rota, Spain and then was ordered to observe Soviet naval activities in the Atlantic off the Azores. She then began a trip back to the Naval Base at Norfolk and disappeared on route. She was last heard from while attempting to send radio messages to Naval Station Rota late on May 20 through May 21. The messages were received by a navy communication station in Nea Makri, Greece, which forwarded them on. Six days later she was reported overdue and Norfolk and a search was launched.

Recently uncovered documents suggest that the Navy knew Scorpion was lost at least three days before the boat was declared “overdue.” A large and secret search had been conducted before the public was made aware that something was wrong.

It wasn’t until late October that the Navy’s oceanographic research ship Mizar located sections of the hull in more than 10,000 feet of water about 400 miles southwest of the Azores. The bathyscaphe Trieste was sent to the site to collect deep water images and other data to help determine what had happened.

Also Gordon Hamilton, an acoustics expert who pioneered the use of hydroacoustics and was operating a listening station in the Canary Islands, produced a clear signal of what is believed to have been the sound of Scorpion’s pressure hull imploding as the boat sank into the crushing depth of the Atlantic.

From evidence and images obtained, it appeared that Scorpion struck the seafloor bow first, digging a deep trench as the wreck settled. The operations department was blown apart forming a debris field, and the sail, which had been part of the hull over the operations department, was found lying on its port side. Oddly, one of the ship’s running lights was locked in the open position as if Scorpion had been operating on the surface at the time of the disaster. The engine room in the aft section was telescoped forward into the larger-diameter hull section.

Peter Palermo, head of a submarine structure analysis group, said he could not rule out sabotage or collision as plausible causes of the Scorpion disaster. He said the position of the masts, the open running light and “other evidence” indicated the sub may have been on or near the surface when it got into trouble. He said a precursor signal that occurred 22 minutes before the “acoustic train” left by the sinking might have been caused by an internal explosion.

For a while Navy researchers considered the possibility of a torpedo explosion within the submarine as the cause of the wreck, but examination of the wreckage eventually allowed them to rule this out.

In the end the official ruling by a board of inquiry could only be that “some unknown incident or chain of incidents caused the Scorpion to sink out of control.”