Why a U.S. Navy Spy Submarine Is Flying the Jolly Roger

USS Jimmy Carter was the last of three Seawolf-class submarines built through 1990s and 2000s. Designed to fight the latest Soviet submarines during the Cold War, the Seawolf class is an astonishing 70 times quieter than the previous class of attack submarines, the Los Angeles class. The Seawolf subs were also built with HY-100 steel hulls, giving them a diving depth of up to 2,000 feet—more than three times the diving depth of her predecessors.

http://www.popularmechanics.com/military/weapons/news/a28209/navy-spy-sub-jolly-roger-uss-jimmy-carter/