Why did Britain win the Battle of Britain in 1940?

Transcript
Operational aircraft and crews in the Battle of Britain

Catalogue ref: AIR 20/4174

BATTLE OF BRITAIN.
FIGHTER COMMAND-OPERATIONAL AIRCRAFT AND CREWS
AS AT




*As at 16.7.40 (earliest available)
N.B. Orders of Battle for this period did not show I.R.

Air Ministry War Room.
26th October, 1945.