August 15 - the heaviest fighting of the Battle of Britain occurs, with the loss of 46 British and 76 German aircraft.
August 25-26 - Britain makes its first air raid on Berlin of the war.
August 31 - Polish 303 Squadron , the most efficient allied unit of the Battle of Britain, enters action.
September
September 7 - Hermann Göring orders the Luftwaffe to stop targeting British airfields and attack London itself instead.
September 7-September 8 - the largest mass air combat in history takes place over Britain, with 1,200 British and German aircraft operating in an area of only 24 x 48 km (15 x 30 miles).
September 15 - Germany makes its heaviest daylight raid on London
September 30 - the Battle of Britain is said to be over, with Hitler's planned invasion of Britain ("Operation Seelöwe") postponed indefinitely.
October
October 8 - No. 71 Squadron RAF , "Eagle Squadron" is formed, comprising American volunteers.
October 8 - Josef František, the Czech ace (17 victories) - the most efficient allied pilot of the Battle of Britain, died in an aircrash.
November
November 5 - four RAF squadrons are deployed to Greece to support the country against Italian attacks.
November 11 - regular ferry flights of US-built warplanes commence across the Atlantic.
