No. 639 Squadron RAF was an anti aircraft co-operation squadron of the Royal Air Force from 1943 to 1945.
The squadron was formed at RAF Cleave on 1 December 1943, from 1602 Flight, 1603 Flight, 1604 Flight and 1618 Flight for anti-aircraft co-operation duties with the Hawker Henley. The main role was to provide target towing duties over Cornwall. In addition the Hawker Hurricane was used as a radar target and to fly low-level simulated attacks on troops. The squadron was disbanded on 30 April 1945.
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