ARTCC

In air traffic control, an Area Control Center (ACC), also known as a Center, is a facility responsible for controlling instrument flight rules aircraft en route in a particular volume of airspace (a Flight Information Region) at high altitudes between airport approaches and departures. In the United States, such a Center is referred to as an Air Route Traffic Control Center (ARTCC).
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A facility established to provide air traffic control service to aircraft operating on an Instrument Flight Rules (IFR) flight plan within controlled airspace and principally during the en route phase of flight. When equipment capabilities and controller workload permit, certain advisory and assistance services may be provided to Visual Flight Rules (VFR) aircraft. (FAA2) (FAA13) (FAA14)

Air Route Traffic Control Center
  

Air Route Traffic Control Center
  

(See AIR ROUTE TRAFFIC CONTROL CENTER.)