To understand how air traffic control works, the airspace must be imagined as if divided in precise sectors. Terminal Radar Approach Control (TRACON) sections handle the flow of departing and approaching aircraft, whereas Air Route Traffic Control Centers (ARTCC) controls larger areas of enroute traffic.
Pilots prepare a flight plan containing information, such as intended airspeed, cruising altitude and route. A controller, known as a ''flight data person,'' reviews the flight plan and gives clearance to depart. Afterward, a ground controller gives the pilot radio instructions for taxiing from the gate to the takeoff runway.
Once deemed safe, the local controller in the tower gives the pilot clearance for takeoff. Once in the air, the pilot enters in communication with the departure controller at the TRACON facility. The departure controller uses radar to monitor the aircraft and guides the pilot to follow specific ascent corridors through the TRACON airspace
The departure controller monitors the flight during ascent until the en route portion. Once out of TRACON airspace, ARTCC airspace takes over where a radar associate controller provides updated weather and air-traffic information, and reviews the flight-plan.
Once nearing destination, the approach controller directs approaching planes to lower altitudes merging them into a single line towards the airport. Once again within TRACON airspace, the pilot is instructed to align the plane with the runway. A local controller in the airport tower gives clearance to land. The ground controller finally gives details for taxiing from the runway to the gate.
