air traffic control unit
A generic term meaning variously, area control center, approach control office, or aerodrome control tower. As the circumstances require, an ATC (air traffic control) unit may be (i) an area control center (ACC) established to provide ATC services to IFR (instrument flight rules) and VFR (visual flight rules) aircraft; (ii) a terminal control unit established to provide ATC services to IFR and VFR aircraft arriving at, or departing from, one or more airports; or (iii) an airport control tower unit established to provide ATC services to airport traffic. Also called an ATC unit.
An Illustrated Dictionary of Aviation Copyright © 2005 by The McGraw-Hill Companies, Inc. All rights reserved