Anti-aircraft warfare
Measures to combat enemy aerial forces
Anti-aircraft warfare (AAW) or air defence (air defense in American English) is the counter to aerial warfare and includes "all measures designed to nullify or reduce the effectiveness of hostile air action". It encompasses surface-based, subsurface (submarine-launched), and air-based weapon systems, in addition to associated sensor systems, command and control arrangements, and passive measures (e.g. barrage balloons).
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