airborne early warning and control

An Airborne Early Warning (AEW) system is a radar system carried by an aircraft which is designed to detect other aircraft. Used at a high altitude, the radars allow the operators to distinguish between friendly and hostile aircraft hundreds of miles away.AEW aircraft are used for defensive and offensive air operations. The system is used offensively to direct fighters to their target locations, and defensively to counter attacks. Many countries have their own AEW systems, although the E-3 Sentry and Grumman E-2C Hawkeye are the popular systems worldwide. The Sentry was built by the Boeing Defense and Space Group (now Integrated Defense Systems) and is widely considered to be an international benchmark for AEW systems. It is based on the Boeing 707 aircraft. The E-2 Hawkeye, which entered service in 1965, is arguably the most widely used AEW system. The E-3 Sentry is not strictly an AEW system, as it has far more functionality—see Airborne Warning and Control System. For the Japan Air Self-Defense Force, the E-3 technology has been fitted into the Boeing E-767.
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Air surveillance and control provided by airborne early warning aircraft which are equipped with search and height-finding radar and communications equipment for controlling weapon systems. See also air picket. 1/2/73

Surveillance aérienne et contrôle fournis par aéronefs d'alerte lointaine en vol, équipés d'un radar de veille et d'altimétrie ainsi que d'appareils de transmissions en vue d'assurer le contrôle des moyens de défense aérienne. Voir aussi avion piquet radar. 1/2/73