HMS Salmon (N65)

HMS Salmon was a Royal Navy S-class submarine which was launched on 30 April 1934, and fought in the Second World War. Salmon is one of twelve boats named in the song "Twelve Little S-Boats".

On 4 December 1939, while on patrol in the North Sea, Salmon torpedoed and sank GS U-36 (1936).

On 12 December 1939, Salmon sighted the German liner SS Bremen (1929). While challenging Bremen, an escorting Dornier Do 18 seaplane forced Salmon to dive. After diving the Salmon's commander, Lieutenant Commander E. O. Bickford, decided not to torpedo the liner because he believed she was not a legal target. Bickford's decision not to fire on Bremen likely delayed the start of unrestricted submarine warfare in the war.

On 13 December 1939, Salmon sighted a fleet of German warships. She fired a spread of torpedoes which damaged two German cruisers (one was GERMAN CRUISER Leipzig, the other, her younger sister ship, GERMAN CRUISER Nürnberg). Salmon evaded the fleet's destroyers, which hunted her for two hours.

She was lost, probably sunk by a mine, on 9 July 1940.