Description
The D-class submarines were enlarged versions of the preceding United States C-class submarine, C class, the first American submarines armed with four torpedo tubes. They were built by the Fore River Shipbuilding Company of Quincy, Massachusetts, under a subcontract from the Electric Boat Company of Groton, Connecticut. They had a length of length overall, overall, a beam (nautical), beam of and a mean draft (ship), draft of . They displacement (ship), displaced on the surface and submerged. The D-class boats had a crew of 1 officer and 14 enlisted men. They had a diving depth of .Friedman, p. 306 For surface running, they were powered by two New London Ship and Engine Company, NELSECO gasoline engines, each driving one propeller shaft.Gardiner and Gray, p. 127 When submerged each shaft was driven by a electric motor. Two 60-electrochemical cell, cell battery (electrical), batteries provided power when submerged. They could reach on the surface and underwater. On the surface, the boats had a range of at and at submerged. The boats were armed with four 18-inch (45.7 cm) torpedo tubes in the bow. They did not carry reloads for them. They were the first US submarines to have four forward torpedo tubes which was standard until the Tambor-class submarine, ''Tambor'' class which joined the fleet in 1940. These vessels included some features intended to increase underwater speed that were standard on US submarines of this era, including a small sail and a rotating cap over the torpedo tube muzzles. For extended surface runs, the small sail was augmented with a temporary piping-and-canvas structure. Apparently the "crash dive" concept had not yet been thought of, as this would take considerable time to deploy and dismantle. This remained standard through the United States L-class submarine, L class, commissioned 1916-1917. The streamlined, rotating torpedo tube muzzle cap eliminated the drag that muzzle holes would otherwise cause. In the stowed position, the submarine appears to have no torpedo tubes, as the holes in the cap are covered by the bow stem. This feature remained standard through the United States K-class submarine, K class, after which it was replaced with shutters that were standard through the 1950s.Ships
* was laid down on 16 April 1908, launched on 8 April 1909 and was commissioned on 23 November 1909 as ''Narwhal''. Renamed ''D-1'' on 17 November 1911, the submarine was decommissioned on 8 February 1922 and sold afterwards. * was laid down on 16 April 1908, launched on 16 June 1909 and was commissioned on 23 November 1909 as ''Grayling''. Renamed ''D-2'' on 17 November 1911, the submarine was decommissioned on 18 January 1922 and sold afterwards. * was laid down on 16 April 1908, launched on 12 March 1910 and was commissioned on 8 September 1910 as ''Salmon''. Renamed ''D-3'' on 17 November 1911, the submarine was decommissioned on 20 March 1922 and sold afterwards.Notes
References
* * * Silverstone, Paul H., ''U.S. Warships of World War I'' (Ian Allan, 1970), . *External links