'Specimen' was the British use of the pioneering but now wholly obsolete aircraft carrier Pegasus (ex-Ark Royal) to provide a measure of air defence for North Atlantic convoys in the North-Western Approaches (December 1940).

Completed in 1914 as the world’s first ship designed and built as a seaplane carrier, Pegasus was converted into the prototype fighter catapult ship in November 1940, and carried three Fairey Fulmar two-seat fighters of No. 807 Squadron between 1 December and 10 February 1941, when these aircraft were replaced by machines from No. 804 Squadron between 10 February and 23 July. The task of the embarked fighters was the defence convoys against attacks by Focke-Wulf Fw 200 maritime patrol bombers and to prevent them from sending radio location reports to U-boats. If out of range of land, the fighters had to ditch at sea, their crews hoping to be recovered by a ship from their convoy. Pegasus escorted nine convoys between December 1940 and July 1941.