U.S. Air Force (United States Air Force, the acronym for the USAF) in the United States Air Force part of the armed forces. Its mission is "through the air, space and cyberspace force in the protection of the United States and its interests", which in September 8, 1947 formally established. U.S. Air Force is the world's largest, most advanced technology of the Air Force. U.S. Air Force in 2006 were 348,953 military personnel in service, the Air Force National Guard and Air Force Reserve 235,571 people. As of September 30, 2006, the U.S. Air Force unmanned aerial vehicles equipped with a total of about 160, manned aircraft 4,282 aircraft (including 172 bombers, 1,619 fighter aircraft, 160 helicopters, reconnaissance aircraft, AWACS 137, 103 special operations aircraft aircraft, 278 air refueling aircraft, trainer aircraft 1,284 aircraft, 529 transport aircraft), while the air force of 1,321 National Guard aircraft, as well as the 410 Air Force Reserve; 2,161 pieces of space-based cruise missiles, and 580 intercontinental ballistic missiles