A number of Swallows were taken on charge during late 1940 by the Royal Air Force's Glider Training Squadron within the Central Landing Establishment based at RAF Ringway near Manchester. Their propellors were removed and tow hooks were attached to each wing leading edge. The Swallows were towed singly, in pairs and in threes by retired Armstrong Whitworth Whitley bombers before being released to glide to their simulated "target" on the airfield. This unusual procedure was adopted to assist the evaluation of the future use of heavy gliders in assaults on enemy positions.