HMS Subtle (P251)

HMS Subtle was a S-class submarine of the third batch built for the Royal Navy during World War II. She survived the war and was scrapped in 1959.

Design and description
The last 17 boats of the third batch were significantly modified from the earlier boats. They had a stronger hull, carried more fuel and their armament was revised. The submarines had a length of 217 ft overall, a beam of 23 ft and a draft of 14 ft. They displaced 842 LT on the surface and 990 LT submerged. The S-class submarines had a crew of 48 officers and ratings. They had a diving depth of 350 ft.

For surface running, the boats were powered by two 950 bhp diesel engines, each driving one propeller shaft. When submerged each propeller was driven by a 650 hp electric motor. They could reach 14.75 kn on the surface and 9 kn underwater. On the surface, the third batch boats had a range of 7500 nmi at 10 kn and 120 nmi at 3 kn submerged.

The boats were armed with seven 21-inch (533 mm) torpedo tubes. A half-dozen of these were in the bow and there was one external tube in the stern. They carried six reload torpedoes for the bow tubes for a grand total of thirteen torpedoes. Twelve mines could be carried in lieu of the internally stowed torpedoes. They were also armed with a 3-inch (76 mm) deck gun.

Construction and career
HMS Subtle was constructed by Cammell Laird and launched on 27 January 1944. She survived the Second World War, spending the period between December 1944 and May 1945 with the Eastern Fleet. Here, she sank a Japanese coaster and six sailing vessels. Together with her sister, HMS Statesman (P246), she helped in the tracking and sinking of the Japanese heavy cruiser Haguro. Subtle was finally sold off to be broken up in July 1959 in Charlestown.