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AIR FORCE

Capitalize when preceded by name of country or when name is well established:
  United States Air Force
Royal Air Force (RAF)

French Air Force
Soviet Air Force, etc.
Capitalize the Air Force in subsequent references to the U.S. Air Force (which was preceded by:
  the Air Force (USAF)

the United States Army Air Forces
but lowercase such references to any foreign air force.

Spell out and capitalize units of the U.S. Air Force through Tenth:
 
Fifth Air Force
11th Air Force

474th Fighter Wing
For Army ranks and abbreviations see MILITARY RANKS.

See also:      ARMY, COAST GUARD, MARINE CORPS, NAVY
                        armed forces, armed services, special forces
                        MILITARY UNITS
                        Ranger, Rangers, SEAL, SEALs
                       TITLES OF PERSONS.