The *third world* United States Navy operated Diesel boats until the retirement of the USS Dolphin AGSS 555, first laid down in 1962, commissioned on August 17, 1968, until its retirement in 2007. Last I heard, it held the records for both the deepest dive by a U.S. sub and the deepest underwater firing of a torpedo, as well as racking up over 1500 dives during its career.
I don't reckon you know what these are.
