A surveillance aircraft is an aircraft used for surveillance—collecting information over time. They are operated by military forces and other government agencies in roles such as intelligence gathering, battlefield surveillance, airspace surveillance, observation (e.g. artillery spotting), border patrol and fishery protection. This article concentrates on aircraft used in those roles, rather than for traffic monitoring, law enforcement and similar activities.
Surveillance aircraft usually carry no armament, or only limited defensive armament. A surveillance aircraft does not necessarily require high-performance capability or stealth characteristics. It may be a modified civilian aircraft. Surveillance aircraft have also included moored balloons (e.g. TARS) and Unmanned Aerial Vehicles (UAVs).
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