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Memphis air traffic control center

The air traffic control center at Memphis (1965).

Air Traffic Control

Air traffic control involves monitoring the movements of all aircraft, both in the air and on the ground, in the vicinity of an airport. Its main purpose is to keep aircraft safely separated to prevent accidents. Air traffic control is needed so that the risk of collision becomes extremely low. This can be achieved only by strictly following procedures that are set out and monitored by air traffic controllers, individuals who direct air traffic within assigned airspace and control moving aircraft and service vehicles at airports.

In flight, an aircraft follows en route air traffic control instructions as it flies through successive flight information regions. When it approaches an airport for landing, the aircraft enters the terminal control area where it is monitored by controllers using radar and who constantly tell pilots how to navigate within the area. Controllers also monitor the aircraft all the way to the ground and tell the pilot how to maneuver on the ground to avoid collisions on the ground of the airfield and how to reach its final location where passengers can disembark. Departing aircraft go through a reverse procedure. Overall, the degree of control depends greatly on the weather conditions. In general, the better the weather, then the less the control.

The International Civil Aviation Organization (ICAO), defines the objectives of air traffic control as:

  • Preventing collisions between aircraft in flight
  • Preventing collisions between aircraft on the maneuvering area of an airport and obstructions on that area
  • Expediting and maintaining an orderly flow of air traffic
  • Providing advice and information useful for the safe and efficient conduct of flights
  • Notifying appropriate organizations regarding aircraft in need of search and rescue aid, and assisting such organizations as required