An air force in the broadest sense is the national military branch that primarily conducts aerial warfare. More specifically, it is the branch of a nation's armed services that is responsible for aerial warfare as distinct from an army aviation or naval aviation units. Typically, air forces are responsible for gaining control of the air, carrying out strategic and tactical bombing missions, and providing support to land and naval forces often in the form of aerial reconnaissance and close air support.
Four fighters and a KC-135 of the USAF
USAF B-2 Spirit stealth strategic bomber
Refuelling a Jaguar GR1 of the Royal Air Force (1991)
RAF Supermarine Spitfire played a vital role in British victory during the Battle of Britain.
Aerial warfare is the use of military aircraft and other flying machines in warfare. Aerial warfare includes bombers attacking enemy installations or a concentration of enemy troops or strategic targets; fighter aircraft battling for control of airspace; attack aircraft engaging in close air support against ground targets; naval aviation flying against sea and nearby land targets; gliders, helicopters and other aircraft to carry airborne forces such as paratroopers; aerial refueling tankers to extend operation time or range; and military transport aircraft to move cargo and personnel.
A United States Air Force F-4 Phantom II releasing aerial bombs over a bombing range in Bardenas Reales, Spain in 1986
World War I fighter planes over Europe, 1915–1918