The H-class submarines had a length of 150 feet 4 inches (45.8 m) overall, a beam of 15 feet 10 inches (4.8 m) and a mean draft of 12 feet 5 inches (3.8 m). They displaced 358 long tons (364 t) on the surface and 467 long tons (474 t) submerged. The boats had a crew of 2 officers and 23 enlisted men. They had a diving depth of 200 feet (61.0 m).[1]
For surface running, they were powered by two New London Ship & Engine Co. 475-brake-horsepower (354 kW) diesel engines, each driving one propeller shaft. When submerged each propeller was driven by a 170-horsepower (127 kW) Electro Dynamic Co. electric motor. They could reach 14 knots (26 km/h; 16 mph) on the surface and 10.5 knots (19.4 km/h; 12.1 mph) underwater.[1] On the surface, the boats had a range of 2,300 nautical miles (4,300 km; 2,600 mi) at 11 knots (20 km/h; 13 mph) and 100 nmi (190 km; 120 mi) at 5 knots (9.3 km/h; 5.8 mph) submerged.[2]
The boats were armed with four 18-inch (450 mm)torpedo tubes in the bow. They carried four reloads, for a total of eight torpedoes.[2]
Construction and career
H-4 was launched on 9 October 1918, and commissioned on 24 October 1918. Stationed at San Pedro, California — first with Submarine Division 6 (SubDiv 6) and then SubDiv 7 — H-4 participated in various battle and training exercises along the West Coast with her sister H-boats. These exercises were interrupted by occasional patrol duty off Santa Catalina Island and periodic overhauls at Mare Island.
In company with the two sub divisions and tenderBeaver, H-4 sailed from San Pedro on 25 July 1922 and reached Norfolk, Virginia on 14 September via Magdalena Bay, Corinto, and Coco Solo. She decommissioned there on 25 October. H-4 was struck from the Naval Vessel Register on 26 February 1931 and sold for scrap on 14 September.
Friedman, Norman (1995). U.S. Submarines Through 1945: An Illustrated Design History. Annapolis, Maryland: Naval Institute Press. ISBN1-55750-263-3.
Gardiner, Robert & Gray, Randal, eds. (1985). Conway's All the World's Fighting Ships 1906–1921. Annapolis, Maryland: Naval Institute Press. ISBN0-85177-245-5.