2. USS Scorpion, another nuclear submarine, was lost in May, 1968
USS Scorpion was a Skipjack class nuclear submarine due to return to its homeport of Norfolk in May, 1968. When the Navy announced that the submarine was overdue, and that its last transmission had been received on May 21, speculation over its disappearance ran rampant. On June 5 the Navy announced Scorpion was presumed lost, and on June 30 the vessel was stricken from the Navy’s registry of ships. A search began, which used the sounds of explosions recorded by undersea sonar. By October it was agreed that Scorpion had been sunk on May 22, 1968, and its final resting place was known to the Navy.
By 1969 the official Navy findings were that Scorpion was destroyed when it passed its designed crush depth, due to uncontrolled flooding. The cause of the flooding was undetermined. This led to the development of numerous theories within and outside the Navy, including speculation that the submarine had been sunk by Soviet ships it had been tasked with observing, an underwater torpedo battle, a shipboard torpedo accident, and several others. The Navy took extensive photographs of the wreck site, which in 1985 remained classified. The Navy did point out that the sounds recorded by the undersea sonar (SOSUS) were not those of explosions, but of implosions as the hull was crushed.