After over a year of night Zeppelin raids, on the night of 2–3 September 1916, a BE2c flown by Captain William Leefe Robinson downed the SL 11, the first German airship to be shot down over Britain. This action won the pilot a Victoria Cross and cash prizes totaling £3,500 put up by a number of individuals. This downing was not an isolated victory; five more German airships were similarly destroyed between October and December 1916, and caused the airship campaign to gradually be diminished over the next year with fewer raids mounted.[N 2]
Because of airships' limitations, the Luftstreitkräfte began to introduce long-range heavy bombers, starting with the Gotha G.IV aircraft that gradually took over the offensive. While their early daylight raids in May 1917 were able to easily evade the weak defenses of London, the strengthening of the home defence fighter force led to the Germans switching to night raids from 3 September 1917. To counter night attacks, Sopwith Camel day fighters were deployed in the night fighter role. The Camels' Vickers guns were replaced by Lewis guns mounted over the wings, as the flash from the Vickers tended to dazzle the pilot when they were fired, and synchronised guns were considered unsafe for firing incendiary ammunition. Further modification led to the cockpit being moved rearwards. The modified aircraft were nicknamed the "Sopwith Comic". To provide suitable equipment for Home Defence squadrons in the north of the UK, Avro 504K trainers were converted to night fighters by removing the front cockpit and mounting a Lewis gun on the top wing.