The history of the Royal Air Force, the air force of the United Kingdom, spans nearly a century of British military aviation. The RAF was founded in 1918, toward the end of World War I by merging the Royal Flying Corps and the Royal Naval Air Service.After the war, the RAF was greatly reduced in size and during the inter-war years it was used to police the British Empire.he newly created RAF was the most powerful air force in the world on its creation, with over 20,000 aircraft and over 300,000 personnel (including the Women's Royal Air Force). The squadrons of the RFC kept their numerals while those of the RNAS were renumbered from 201 onwards.