Formed on 1 April 1918 from the merger of the Royal Naval Air Service with the Royal Flying Corps, the Royal Air Force was the first fully autonomous military air arm in the world. This book is a comprehensive, single source reference on the RAF and the vital part it played in the Second World War. It opens with a brief history of the service, followed by a chapter that reviews its situation on the outbreak of war. The chapters that follow look at the structure of the RAF, from the Air Ministry and Chief of the Air Staff down to squadron level, to include each of the Commands, including Transport Command (a creation of the war years). The main aircraft types used are listed, as well as a full listing of squadrons and airfields in the British Isles. The training of personnel, and such matters as uniforms, rank insignia, medals and life on a typical airfield, are also covered. The main battles or campaigns in which the service was involved are also described.