Barbel-class submarine

Last class of diesel-electric submarine operated by US Navy

The Barbel-class submarines, the last diesel-electric propelled attack submarines built by the United States Navy, incorporated numerous, radical engineering improvements over previous classes. They were the first production warships built with the teardrop-shape hull first tested on the experimental USS Albacore, and the first to combine the control room, attack center, and conning tower in the same space in the hull. They were of double hull design with 1.5-inch thick HY80 steel. This class of submarine became part of the United States Navy's fleet in 1959 and was taken out of service 1988–1990, leaving the Navy with an entirely nuclear-powered submarine fleet.

This keyword could refer to multiple things. Here are some suggestions: