HMS Swordfish (61S)
 HMS Swordfish (61S) was a group one British S class submarine that was sunk on a combat patrol in the English Channel in November 1940 during the Second World War.Nothing was heard from her following her departure from Portsmouth on 7 November 1940 with 40 crew on board to relieve HMS Usk which was on patrol off the Western Approaches near Brest France. At the time it was thought that she had been sunk by a German destroyer.