HMS C20 was a Group 2 C Class submarine built at Chatham. She was ordered as part of the 1907/1908 building program.


She was laid down on No 7 Slip on 1st June 1908. She was launched into the Medway on 27th November 1909 by Lady Drury, wife of the C-in-C Nore, Admiral Sir Charles Drury KCB RN. After fitting out, she commissioned at Chatham on 31st January 1910.


The C Class Submarine:





C20 from the air





In common with her sister-boats, she represented the last British evolution of the original Holland design. Because of a lack of reserve bouyancy, C Class submarines handled poorly on the surface, but their shape, reminiscent of modern submarines, gave them good handling characteristics when dived.


Armed with 2 18" torpedo tubes and carrying a crew of 16 men, C20 was a primitive submarine, even by First World War standards, lacking even a proper toilet for her crew.


Just before the outbreak of WW1, on 10th July 1914, HMS C20 earned her claim to fame when she was visited by the King. Her WW1 career was spent on coastal patrols based out of Leith, transferring to Dover and ending the war at Portsmouth.


The C Class submarines were employed on a curious method of trying to engage German U-Boats which were playing havoc with the Coastal trade. They would be towed submerged behind a bait vessel, usually a trawler, which when challenged by a U-Boat, would transmit instructions to the submarine via a telephone cable. The submarine would then slip it's tow and work itself into a position to torpedo the U-Boat. It did actually work on occasion, but C20 isn't recorded as having any success with it.


Obsolete by the end of the Great War, HMS C20 was sold for scrap on 26th May 1921 at Sunderland.