Definition
Air traffic control is the ground-based service, provided by trained controllers, that directs aircraft on the ground and through controlled airspace to keep them safely separated from one another and to organize the flow of traffic. Controllers issue instructions and clearances to pilots by radio, and pilots are required to comply with those instructions when operating in controlled airspace.
Plain English
ATC is the team of people on the ground who talk to pilots over the radio and tell them where, when, and how to fly so that aircraft don't run into each other and traffic moves in an orderly way.
Context Anchor
Pilots encounter ATC during radio communication, taxi, takeoff, landing, and flight through areas where controller communication is required or available.
Why Pilots Care
ATC keeps aircraft from colliding, helps pilots navigate through busy airspace, and supplies critical information such as weather, runway status, and traffic advisories.
Intuition Check
ATC does not mean the controller flies the airplane for the pilot. The pilot still flies the aircraft; ATC helps organize traffic by giving instructions, permissions, and information.
Example Sentence 1
After starting the engine, the pilot called ATC for taxi clearance to the active runway.
Example Sentence 2
ATC issued a vector to avoid traffic and then handed the flight off to the next sector.