At on 6 September 1939, a radar fault led to a false alarm that unidentified aircraft were approaching from the east at high altitude over West Mersea, on the Essex coast. No. 11 Group RAF ordered six Hawker Hurricanes to be scrambled from 56 Squadron, based at North Weald Airfield in Essex. The sector controller, Group Captain David Frederick Lucking, sent up the entire unit of 14 aircraft. Unbeknown to the rest of the pilots, two pilot officers took up a pair of reserve aircraft and followed at a distance.