The
United States Air Force (
USAF) is the
aerial warfare service branch of the
United States Armed Forces and one of the seven
American uniformed services. Initially part of the
United States Army, the USAF was formed as a separate branch of the military on 18 September 1947 under the
National Security Act of 1947. It is the most recent branch of the U.S. military to be formed, and is the largest and one of the world's most technologically advanced
air forces. The USAF articulates its core functions as
Nuclear Deterrence Operations,
Special Operations,
Air Superiority,
Global Integrated ISR,
Space Superiority,
Command and Control,
Cyberspace Superiority,
Personnel Recovery,
Global Precision Attack,
Building Partnerships,
Rapid Global Mobility and
Agile Combat Support.