HMS D8 was one of eight D-class submarines built for the Royal Navy during the first decade of the 20th century.

Description

The D-class submarines were designed as improved and enlarged versions of the preceding C class, with diesel engines replacing the dangerous petrol engines used earlier. D3 and subsequent boats were slightly larger than the earlier boats. They had a length of 164 ft overall, a beam of 20 ft and a mean draught of 11 ft. They displaced 495 LT on the surface and 620 LT submerged. The D-class submarines had a crew of 25 officers and ratings and were the first to adopt saddle tanks. For surface running, the boats were powered by two 600 bhp diesels, each driving one propeller shaft. When submerged each propeller was driven by a 275 hp electric motor. They could reach 14 kn on the surface and 9 kn underwater. On the surface, the D class had a range of 2500 nmi at 10 kn. The boats were armed with three 18-inch (45 cm) torpedo tubes, two in the bow and one in the stern. They carried one reload for each tube, a total of six torpedoes.

Construction and career

D8 was laid down on 14 February 1910 by Chatham Dockyard. The submarine was launched on 23 September 1911 and was commissioned on 23 March 1912. D8 fought in the Battle of Heligoland Bight on 28 August 1914 along with sister ships HMS D2 and HMS D3. Then on 18 October 1914, D8 shadowed the GERMAN HOSPITAL SHIP Ophelia which was judged to be spying and was interned. D8 was sold on 19 December 1921 to Pounds.