Appendix A Glossary

APPENDIX A

GLOSSARY

NOTE

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.

NOTE

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."

GLOSSARY A-1