'Early Window' was the designation of British 'Window' (chaff) raids by de Havilland Mosquito twin-engined light bombers of Air Chief Marshal Sir Arthur Harris’s RAF Bomber Command with the object of disrupting the German radar and control networks before the arrival of major air raids, which would therefore receive less and/or more disorganised attention from night-fighters and anti-aircraft artillery (August 1943/May 1945).