The Harrow also served in a novel operational role at the height of The Blitz against Britain in the winter of 1940–1941. Six Harrows equipped No. 420 Flight RAF (later No. 93 Squadron RAF) which used lone Harrows to tow Long Aerial Mines (LAM) into the path of enemy bombers. The LAM had an explosive charge on the end of a long cable and the unorthodox tactic was credited with the destruction of 4–6 German bombers. The experiment was judged of poor value and the planned deployment of Douglas Havocs in the LAM role was cancelled. Nine Harrows were also used by 782 Naval Air Squadron, Fleet Air Arm as transports. After flight refuelling trials, three Harrows were operated by Flight Refuelling Limited and refuelled Short Empire Flying Boats on transatlantic services, two from Gander, Newfoundland and one based in Foynes, Ireland. In 1940, the two aircraft based at Gander were pressed into service with the Royal Canadian Air Force.