10. The expeditions to the sunken submarines provided information regarding their loss
The higher-resolution images obtained at the wreck of USS Thresher helped the Navy confirm that the investigators had been correct in establishing the cause of that vessel’s loss. A seawater piping joint, silver brazed rather than welded, failed and sprayed seawater on an electrical panel, causing a reactor shutdown and subsequent loss of power. When the crew tried to blow the seawater out of the main ballast tanks, moisture in the released high-pressure air caused valves to freeze, blocking airflow, and the submarine slipped, stern first, below crush depth. Photographs provided by Ballard confirmed the scenario.
Photographs and other information at the Scorpion site were not so informative in revealing the cause of the initial catastrophic event which led to the loss of the ship. But they did reveal that the visible portions of the hull were intact, with no evidence of an explosion either outside or internal to the submarine. The hull had telescoped at implosion, with the narrower stern section thrust deeply into the forward section. The official Navy conclusion remained that the ship was lost due to an unknown catastrophic event, but an attack on it by the Soviets (or anyone else) was not supported by the evidence.
