United States D-class submarine

The D-class submarines were a class of three United States Navy submarines, built by the Fore River Shipbuilding Company of Quincy, Massachusetts, under a subcontract from the Electric Boat Company of Groton, Connecticut. All three ships served during World War I providing training for crews and officers, before the class was decommissioned, and sold for scrap in 1922.

Ships

 * USS D-1 (SS-17) was launched in 8 September 1909 and was commissioned on 23 November 1909 as Narwhal. It was decommissioned on 8 February 1922 and sold afterwards.
 * USS D-2 (SS-18) was launched in 16 June 1909 and was commissioned on 23 November 1909 as Grayling. It was decommissioned on 18 January 1922 and sold afterwards.
 * USS D-3 (SS-19) was launched in 12 March 1910 and was commissioned on 8 September 1910 as Salmon. It was decommissioned on 20 March 1922 and sold afterwards.