Introducing project “Military Insignia”, featuring top quality military heraldry designs. Here you will find designer apparel, accessories, custom postage and gifts decorated with Seal of the Department of the Air Force (USAF). The United States Air Force (USAF) is the aerial warfare service branch of the United States Armed Forces and one of the American uniformed services. Initially part of the United States the USAF was formed as a separate branch of the military on September 18, 1947 under the National Security Act of 1947. It is the most recent branch of the U.S. military to be formed, as well as the world's most technologically sophisticated air force. The USAF articulates its core functions in its 2010 Posture Statement 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.