Air Traffic Control
Air Traffic Control is a service provided through the FAA to direct traffic on the ground and in the air. Observation and communication is provided by ground-based air traffic controllers, whose primary responsibility is to separate aircrafts to prevent collisions, efficiently organize the flow of traffic, and to provide information and support for pilots.
Separation is the term used to describe the prevention of aircraft collision by using lateral, vertical, and longitudinal separation of aircrafts. Secondary functions include providing pilots with relevant information, such as weather updates, navigation information, and Notices to Airmen (NOTAMs).
Airport control is conducted primarily through visual observations from the control tower. As stated earlier, Air Traffic Controllers from this Aerodrome or Tower is responsible for the aircrafts operating on the airport grounds and the surrounding air, frequently 2 to 5 nautical miles in radius. Available at these control towers are radar displays to locate and identify individual aircrafts on a map. From the screen, the aircraft’s identification number, speed, heading, and other information can be obtained. The three general operational categories of airport control are: ground control, air control, and clearance delivery. Ground control is held accountable for the management of aircrafts in the airport “maneuvering” areas. This includes taxiways, inactive runways and holding areas. Any aircraft, vehicle, or person in this area is required to obtain clearance before engaging in any activities. Communication is clearly maintained via VHF radio. Air control is in charge of aircrafts on active runways, as the Air Control function of the Air Traffic Control clears an aircraft for take-off or landing. This function must make sure that runways are clear and that there are no unsafe conditions present. Finally, clearance delivery is the function that oversees the issuing of route clearances. Approach and departure control can also be categorized under airport control, as they handle the traffic within 30 to 50 nautical miles radius from the control tower airport.
Another service provided by Air Traffic Control, other than airport control, is en-route control. This refers to the management of traffic between airports. As pilots fly under either Visual Flight Rules (VFR) or Instrument Flight Rules (IFR), Air Traffic Control must offer different responsibilities depending on the flight rules being utilized. En-route Air Traffic Control issue clearances and instructions to aircrafts in the air, as well as for aircrafts operating from smaller airports under the supervision of the main, controlled airport.