Coordinates air traffic over regions.

The air traffic control radar beacon system is a system used in air traffic control to enhance surveillance radar monitoring and separation of air traffic.

an Area Control Center operated by the Federal Aviation Administration and located at Lawson Rd SE, Leesburg, Virginia, United States.

(radio communications: "Chicago Center") one of 22 Air Route Traffic Control Centers (ARTCCs) operated by the United States Federal Aviation Administration.

(ZBW; in radio communications, "Boston Center") one of 22 Air Route Traffic Control Centers in the United States, located in Nashua, New Hampshire.