USS Thornback, a Tench-class submarine, was the only ship of the United States Navy to be named for the thornback, a slender member of the shark family with a long pointed snout and a sharp spine at the end of each dorsal fin, native to northern Atlantic waters ranging from the temperate to the Arctic.
Her keel was laid down on 5 April 1944 by the Portsmouth Navy Yard. She was launched on 7 July 1944 sponsored by Mrs. Peter K. Fischler, and commissioned on 13 October 1944 with Commander Ernest P. Abrahamson in command.
Official Website http://www.rmk-museum.org.tr/rmk_denizalti.htm
Coordinates 41°2'29.028" N 28°56'51.561" E