The structure of the American Air Force is complex and confusing. Much of it was formed hurriedly during the Second World War, but elements can be traced back as far as the First World War. At its peak, there were almost 2.5 million people employed within its scope both within the United States and overseas in one of the many theatres of operation.

At the start of the Second World War, there were 4 air forces, (designated by district), which were then renumbered 1 – 4 in early 1941. These stayed based within the U.S. covering the West Coast and some training operations on the East Coast and in the southern U.S. The newly established forces were then formed for overseas service. The Fifth, Seventh, Tenth, Thirteenth, Fourteenth and Twentieth covering the Pacific / Asia campaigns; the Eighth, Ninth, Twelfth and Fifteenth, the European…