THIS LIST IS NOT INTENDED TO BE ALL-INCLUSIVE.
Refer to the current version of the AIM, GP, Chapter 2 or the
7110.65 ATC Manual.
AIRPORT SURVEILLANCE RADAR APPROACH - Radar providing position of aircraft by
azimuth and range data without elevation data. It is designed for a maximum range of 60 miles.
Used for terminal approach control. Also used for surveillance approaches. The ASR approach
is conducted in accordance with directions issued by a controller referring only to the
surveillance display. Also see GCA.
AIR ROUTE TRAFFIC CONTROL CENTER - A facility established to provide traffic
control service to IFR flights operating within controlled airspace and principally during the
enroute phase of flight.
ATC CLEARANCE - Authorization by ATC facilities for an aircraft to proceed under specified
traffic conditions within controlled airspace.
ALTITUDE RESTRICTION - An altitude or altitudes, stated in the order flown, which are to
be maintained until reaching a specific point or time. Altitude restrictions may be issued by
ATC due to traffic, terrain, or other airspace considerations.
APPROACH CONTROL FACILITY - A terminal ATC facility that provides approach
control service in a terminal area.
Approach Control service is provided by an Approach Control
facility for arriving and departing aircraft. At some airports not
serviced by an Approach Control facility, the ARTCC provides
limited Approach Control service.)
AUTOMATIC TERMINAL INFORMATION SERVICE - The continuous broadcast of
recorded non-control information in selected terminal areas. Its purpose is to improve controller
effectiveness and to relieve frequency congestion by automating the repetitive transmission of
essential but routine information.
CEILING - The height above the earth's surface of the lowest layer of clouds or obscuring
phenomena that is reported as "broken", "overcast", or "obscuration."