The squadron served at first in the army cooperation role, and later during the Second World War became a tactical bomber unit.

The Hectors and Lysanders were used to dive-bomb German positions and drop supplies to friendly troops near Calais during the late May 1940 Dunkirk evacuation.

[8][9] In August 1941 the squadron became a tactical reconnaissance unit and it began re-equipping with the faster Curtiss Tomahawk.

It re-equipped with the early Allison V-1710 powered Mark I version of the North American Mustang in April 1942, continuing to operate within RAF Army Cooperation Command.

[10] On 15 October 1943 the squadron moved to RAF Lasham, Hampshire and began to equip with the de Havilland Mosquito when it joined No.

[13] The unit's home was in Ringway's Hangar No.7, which had been completed for the squadron in spring 1940, a few months after leaving the airport for wartime service elsewhere.

Initial training with the new jet aircraft was carried out at Avros nearby Woodford Aerodrome, with its longer runway, by courtesy of the squadron's honorary air commodore, Sir Roy Dobson, 613's commanding officer, Squadron Leader Jack Wales DFC, a test pilot for Avros, flew the unit's only Vampire FB.9, WR257 'A' between June 1954 and his death in December 1956 when flight testing the prototype Avro Shackleton MR.3.