On 15 February 1968, USS SCORPION (SSN-589) departed Norfolk, Virginia, for a Mediterranean deployment. The boat was fresh off an overhaul, but only emergency repairs had been made during that period so the boat could deploy again as soon as possible. (Because of the extensive requirements of the SUBSAFE program that had been implemented after the loss of USS THRESHER (SSN-593) in 1963, a full overhaul now took 36 months, four times longer than it had previously.) By May, SCORPION was on her way home. On the twenty-first, the boat, which had been unable to reach Naval Station Rota in Spain, her normal contact, for at least 24 hours, radioed her position to a Navy communications station in Greece. At that point she was about fifty miles south of the Azores. It was the last time anyone would communicate with the sub.
On 27 May 1968, SCORPION was reported as overdue. A search was launched immediately, but nothing was found. On 5 June the boat was presumed lost; she was struck from the Naval Vessel Register twenty-five days later. Meanwhile, an expanded search was launched. Using data collected from a listening station in the Canary Islands, acoustics expert Gordon Hamilton was able to identify what was believed to be the sound of SCORPION’s pressure hull imploding as she sank below crush depth. After analyzing that information, he recommended the Navy search in a specific area. Finally, at the end of October, searchers aboard Mizar, an oceanographic research ship belonging to the Navy, located the boat within the search area Hamilton had recommended. She had gone down about 460 miles southwest of the Azores in nearly 10,000 feet of water. SCORPION had broken in half; her sail had loosed itself from the main body of the sub and lay on the seafloor on its port side. The speed at which the wreckage had plowed into the bottom had caused the after-most portion of the stern section to telescope into the larger-diameter section of hull just forward of it.
The exact cause of SCORPION’s loss is still unknown and widely debated. Theories range from, among others, a “hot-run” torpedo detonating inside one of the boat’s torpedo tubes, to the overheating of a faulty battery inside a torpedo which may have led to a fire in the torpedo room, to a malfunction of the trash disposal unit.
What we know for sure is that 99 Sailors went down with SCORPION and that they remain with their boat, largely undisturbed, in the same spot where she came to rest more than four decades ago.
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