PILOT/CONTROLLER GLOSSARY
PURPOSE

a..
This Glossary was compiled to promote a common understanding of the terms used in the Air Traffic Control system. It includes those terms which are intended for pilot/controller communications. Those terms most frequently used in pilot/controller communications are printed in bold italics. The definitions are primarily defined in an operational sense applicable to both users and operators of the National Airspace System. Use of the Glossary will preclude any misunderstandings concerning the system's design, function, and purpose.

b..
Because of the international nature of flying, terms used in the Lexicon, published by the International Civil Aviation Organization (ICAO), are included when they differ from FAA definitions. These terms are followed by “[ICAO].” For the reader's convenience, there are also cross references to related terms in other parts of the Glossary and to other documents, such as the Code of Federal Regulations (CFR) and the Aeronautical Information Manual (AIM).

c..This Glossary will be revised, as necessary, to maintain a common understanding of the system.

EXPLANATION OF CHANGES

a.. Terms Added:
AUTOMATIC FLIGHT INFORMATION SERVICE (AFIS) - ALASKA FSS ONLY

b..Editorial/format changes were made where necessary. Revision bars were not used due to the insignificant nature of the changes.
A

AAI-
(See ARRIVAL AIRCRAFT INTERVAL.)
AAR-
(See AIRPORT ARRIVAL RATE.)
ABBREVIATED IFR FLIGHT PLANS-An authorization by ATC requiring pilots to submit only that information needed for the purpose of ATC. It includes only a small portion of the usual IFR flight plan information. In certain instances, this may be only aircraft identification, location, and pilot request. Other information may be requested if needed by ATC for separation/control purposes. It is frequently used by aircraft which are airborne and desire an instrument approach or by aircraft which are on the ground and desire a climb to VFR‐on‐top.
(See VFR‐ON‐TOP.)
(Refer to AIM.)
ABEAM-An aircraft is “abeam” a fix, point, or object when that fix, point, or object is approximately 90 degrees to the right or left of the aircraft track. Abeam indicates a general position rather than a precise point.
ABORT-To terminate a preplanned aircraft maneuver; e.g., an aborted takeoff.
ACC [ICAO]-
(See ICAO term AREA CONTROL CENTER.)
ACCELERATE‐STOP DISTANCE AVAILABLE-The runway plus stopway length declared available and suitable for the acceleration and deceleration of an airplane aborting a takeoff.
ACCELERATE‐STOP DISTANCE AVAILABLE [ICAO]-The length of the take‐off run available plus the length of the stopway if provided.
ACDO-
(See AIR CARRIER DISTRICT OFFICE.)
ACKNOWLEDGE-Let me know that you have received my message.
(See ICAO term ACKNOWLEDGE.)
ACKNOWLEDGE [ICAO]- Let me know that you have received and understood this message.