HMS A12

HMS A12 was an A-class submarine (1903) submarine built for the Royal Navy in the first decade of the 20th century. After surviving World War I, she was sold for scrap in 1920.

Design and description
A12 was a member of the first British class of submarines, although slightly larger, faster and more heavily armed than the lead ship, HMS A1. The submarine had a length of 105 ft overall, a beam of 12 ft and a mean draft of 10 ft. They displaced 190 LT on the surface and 206 LT submerged. The A-class submarines had a crew of 2 officers and 9 ratings.

For surface running, the boats were powered by a single 16-cylinder 600 bhp Wolseley petrol engine that drove one propeller shaft. When submerged the propeller was driven by a 150 hp electric motor. They could reach 11 kn on the surface and 6 kn underwater. On the surface, A12 had a range of 500 nmi at 10 kn; submerged the boat had a range of 30 nmi at 5 kn.

The boats were armed with two 18-inch (45 cm) torpedo tubes in the bow. They could carry a pair of reload torpedoes, but generally did not as they would have to remove an equal weight of fuel in compensation.

Construction and career
A12 was ordered as part of the 1903–04 Naval Programme from at Vickers. She was laid down at the shipyard in Barrow-in-Furness in 1903, launched on 3 March 1905 and completed on 23 September.