1947: Today marks the 78th anniversary of the establishment of the USAF as a separate military service.
The predecessor organizations leading up to today’s U.S. Air Force are:
Aeronautical Division, Signal Corps (1 August 1907 – 18 July 1914)
Aviation Section, Signal Corps (18 July 1914 – 20 May 1918)
Division of Military Aeronautics (20 May 1918 – 24 May 1918)
Air Service, U.S. Army (24 May 1918 – 2 July 1926)
U.S. Army Air Corps (2 July 1926 – 20 June 1941)
U.S. Army Air Forces (20 June 1941 – 17 September 1947)