Royal Air Force, abbreviation RAF is the Air Force of the United Kingdom. They were originally formed by Royal Warrant in 1912 as the Royal Flying Corps, superceding the air branch of the Royal Engineers. The Royal Navy Air Service was formed shortly after the outbreak of World War I, in which both forces saw service. In April 1918 the RAF was formed by amalgamation of the RFC and the RNAS.
Between the wars the RAF was responsible for mail and armed forces services, but saw little military action. Of particular note was 1928's air evacuation of civilians from Afghanistan, the first operation of its kind. This period also the formation of the major flying schools that still provide its service personnel.
Perhaps the defining moments of the RAF's existence however, came during the Battle Of Britain. Over the summer of 1940 the RAF held off the Luftwaffe in an air war, perhaps the first of its kind, contributing immensely to the delay of Operation Sea Lion, and helping to turn the tide of World War II.
There were also a RCAF (Canadian), RNZAF (New Zealand)...
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