Air denial

Air supremacy is a position in war where a side holds complete control of air warfare and air power over opposing forces. It is defined by NATO and the United States Department of Defense as the "degree of air superiority wherein the opposing air force is incapable of effective interference."

There are three levels of control of the air:

The degree of a force's air control is a zero-sum game with its opponent's; increasing control by one corresponds to decreasing control by the other. Air forces unable to contest for air superiority or air parity can strive for air denial, where they maintain an operations level conceding air superiority to the other side, but preventing it from achieving air supremacy.

Air power has increasingly become a powerful element of military campaigns; military planners view having an environment of at least air superiority as a necessity. Air supremacy allows increased bombing efforts, tactical air support for ground forces, paratroop assaults, airdrops and simple cargo plane transfers, which can move ground forces and supplies. Air power is a function of the degree of air superiority and numbers or types of aircraft, but it represents a situation that defies black-and-white characterization. NATO forces in air superiority over Kosovo lost a stealth strike aircraft to an "obsolete"Serbian air defense system, and primitive An-2 biplanes (less visible to radar than metal planes) were considered for some time a serious capability of the Korean People's Air Force in North Korea.

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