What is the abbreviation for Britain's air force?

Answer 1

RAF - Royal Air Force.

Military flying started in the British Army in its "Royal Flying Corps". Known as "RFC" for short.

Later, the RFC was separated from the Army to form a new military entity called the Royal Air Force or "RAF" for short.

(The answer below is just a little joke!)

Another answer

In the First World War, The British Air Force were known as the "Royal Flying Club", which in a way, was what they were, as the RFC was formed from all the little English flying Clubs that were scattered around England.

In WW2 they became the RAF, [The Royal Air-Force].

The abbreviation RAF is contained in their brass cap badge and is embroidered on their pilot's wings.