The Fairey Swordfish was a torpedo bomber biplane designed by the Fairey Aviation Company and used by the Fleet Air Arm of the Royal Navy during the Second World War. Originating in the 1930s, the Swordfish, nicknamed "Stringbag", was an outdated design by the start of the war in 1939, but remained in front-line service for years, outliving several types intended to replace it. It was initially operated primarily as a fleet attack aircraft; during its later years it was used as an anti-submarine and training craft. In the anti-submarine role, the Swordfish pioneered the naval use of air to surface vessel (ASV) radar; the aircraft holds the distinction of being the first such implementation upon carrier-borne aircraft, allowing the Swordfish to effectively locate surface ships at night and through clouds.
The Swordfish achieved some spectacular successes, notably the sinking of one and damaging two battleships of the Regia Marina in the Battle of Taranto.