USS Thresher (SSN-593)

The location
It sunk with 'all hands aboard' (that is to say all crew 129 died) during some planned deep diving tests, 10 April 1963, 350 km east of Cape Cod and now lies on the sea bead at a depth of 8,400 ft.

Also see

 * The Soviet Submarine K-19 accident

Links

 * https://en.wikipedia.org/wiki/USS_Thresher_(SSN-593)