ATC glossary

Acronym Meaning
AAR Airport Acceptance Rate or Airport Arrival Rate. The number of arrivals an airport is capable of accepting each hour.
AC or A/C Aircraft
ADZY Advisory
ARPT Airport
ARSR Air Route Surveillance Radar. Air Route Traffic Control Centre (ARTCC) radar used primarily to detect and display an aircraft's position while en route between terminal areas. The ARSR enables controllers to provide radar air traffic control service when aircraft are within the ARSR coverage. In some instances, ARSR may enable an ARTCC to provide terminal radar services similar to but usually more limited than those provided by a radar approach control.
ARTCC Air Route Traffic Control Centre. A facility established to provide air traffic control service to aircraft operating on IFR flight plans within controlled airspace and principally during the en route phase of flight. When equipment capabilities and controller workload permit, certain advisory/assistance services may be provided to VFR aircraft. There are 20 ARTCCs in the continental U.S.
ASR Airport Surveillance Radar. Approach control radar used to detect and display an aircraft's position in the terminal area. ASR provides range and azimuth information but does not provide elevation data. Coverage of the ASR can extend up to 60 miles.
ATC Air Traffic Control. A service operated by appropriate authority to promote the safe, orderly and expeditious flow of air traffic.
ATCSCC Air Traffic Control System Command Centre
ATCT

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Airport Traffic Control Tower. A terminal facility that uses air/ground communications, visual signalling, and other devices to provide ATC services to aircraft operating in the vicinity of an airport or on the movement area. Authorizes aircraft to land or takeoff at the airport controlled by the tower or to transit the Class D airspace area regardless of flight plan or weather conditions (IFR or VFR). A tower may also provide approach control services (radar or nonradar).

 

CDM Collaborative Decision Making. Cooperative effort between the various components of aviation transportation, both government and industry, to exchange information for better decision making.
CDR Coded Departure Routes. Predefined routes used to route air traffic around areas of severe weather.
CIGS Ceilings. The height above the ground of the base of the lowest layer of clouds when over half of the sky is obscured.
CLSD

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Closed

 

EDCT Expected Departure Clearance Time. Time issued to a flight to indicate when it can expect to receive departure clearance. EDCTs are issued as part of Traffic Management Programs, such as a Ground Delay Program (GDP).
EMERG Emergency
EQUIP

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Equipment

 

FSM Flight Schedule Monitor. A tool used by Air Traffic Management Specialists to monitor air traffic demand at airports.
FSS

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Flight Service Station. Air traffic facilities which provide pilot briefing, en route communications and VFR search and rescue services, assist lost aircraft and aircraft in emergency situations, relay ATC clearances, originate Notices to Airmen, broadcast aviation weather and NAS information, receive and process IFR flight plans, and monitor NAVAIDs. In addition, at selected locations, FSSs provide En Route Flight Advisory Service (Flight Watch), take weather observations, issue airport advisories, and advise Customs and Immigration of transborder flights.

 

GDP Ground Delay Program. Ground Delay Programs are implemented to control air traffic volume to airports where the projected traffic demand is expected to exceed the airport's acceptance rate for a lengthy period of time. Lengthy periods of demand exceeding acceptance rate are normally a result of the airport's acceptance rate being reduced for some reason. The most common reason for a reduction in acceptance rate is adverse weather such as low ceilings and visibility.

How it works:
Flights that are destined to the affected airport are issued Expected Departure Clearance Times (EDCT) at their point of departure. Flights that have been issued EDCTs are not permitted to depart until their Expected Departure Clearance Time. These ECDTs are calculated in such a way as to meter the rate that traffic arrives at the affected airport; ensuring that demand is equal to acceptance rate. The length of delays that result from the implementation of a Ground Delay Program depends upon two factors: how much greater than the acceptance rate the original demand was, and for what length of time the original demand was expected to exceed the acceptance rate.

GPS Global Positioning System
GS

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Ground Stop. Ground Stops are implemented for a number of reasons. The most common reasons are:
 
  • To control air traffic volume to airports when the projected traffic demand is expected to exceed the airport's acceptance rate for a short period of time.
  • To temporarily stop traffic allowing for the implementation of a longer-term solution, such as a Ground Delay Program.
  • The affected airport's acceptance rate has been reduced to zero.

How it works:
Flights that are destined to the affected airport are held at their departure point for the duration of the Ground Stop.

 

IFR Instrument Flight Rules. A set of rules governing the conduct of flight under instrument meteorological conditions.
ILS

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Instrument Landing System. A ground based precision approach system that provides course and vertical guidance to landing aircraft.

 

LAADR Low Altitude Airway Departure Route.
LAHSO Land and Hold Short Operations. Operations which include simultaneous takeoffs and landings and/or simultaneous landings when a landing aircraft is able and is instructed by the controller to hold short of the intersecting runway/taxiway or designated hold-short point. Pilots are expected to promptly inform the controller if the hold short clearance cannot be accepted.
LO CIGS Low Ceilings. Low clouds.
LOC

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Localizer. The component of an ILS that provides course guidance to the runway.

 

MINIT Minutes in Trail. A specified interval between aircraft expressed in time.
MIT Miles in Trail. A specified interval between aircraft expressed in nautical miles.
MULTI-TAXI

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Many aircraft trying to taxi at once, creating congestion.

 

N90 New York TRACON
NAS National Airspace System. The common network of U.S. airspace; air navigation facilities, equipment and services, airports or landing areas.
NAVAID Navigational Aid. Any visual or electronic device, airborne or on the surface, which provides point-to-point guidance information or position data to aircraft in flight.
NM Nautical Mile. International unit equal to 6076.115 feet (1852 meters).
NOTAM Notice to Airmen. A notice containing information (not known sufficiently in advance to publicize by other means) concerning the establishment, condition, or change in any component (facility, service, or procedure of, or hazard in the National Airspace System) the timely knowledge of which is essential to personnel concerned with flight operations.
NRP

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National Route Plan. The NRP is a set of rules and procedures which are designed to increase the flexibility of user flight planning within published guidelines.

 

OTS

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Out of service

 

RLSD Released
RRTES Reroutes
RWY Runway
RWY CONFIG Runway Configuration
RY

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Runway

 

SPO Strategic Plan of Operation. See SPT.
SPT Strategic Planning Team. The Strategic Planning Team acts as a focal point for the development of collaborative Strategic Plans of Operation. Their goal is to provide advanced planning information for system users and air traffic facilities in order to maximize the utilization of the NAS in an organized and equitable manner.
STMP Special Traffic Management Program. Reservation program implemented to regulate arrivals and/or departures at airports that are in areas hosting special events such as the Masters Golf Tournament and Indianapolis 500.
SVRWX Severe Weather
SWAP

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Severe Weather Avoidance Plan. An approved plan to minimize the effect of severe weather on traffic flows in impacted terminal and/or ARTCC areas. SWAP is normally implemented to provide the least disruption to the ATC system when flight through portions of airspace is difficult or impossible due to severe weather.

 

TACAN Tactical Air Navigation Aid. An ultra-high frequency electronic rho-theta air navigation aid which provides suitably equipped aircraft a continuous indication of bearing and distance to the TACAN station.
TFC Traffic
TRACON Terminal Radar Control Facility. A terminal ATC facility that uses radar and nonradar capabilities to provide approach control services to aircraft arriving, departing, or transiting airspace controlled by the facility.
TSD Traffic Situation Display. A tool used by Traffic Management Specialists to monitor the position of air traffic and to determine the traffic demand on airports and sectors.
TSTMS

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Thunderstorms

 

UTC

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Coordinated Universal Time (abbreviated as UTC, and therefore often spelled out as Universal Time Coordinated and sometimes as Universal Coordinated Time) is the standard time common to every place in the world. Formerly and still widely called Greenwich Mean Time (GMT) and also World Time, UTC nominally reflects the mean solar time along the Earth's prime meridian.

 

VAPS Visual Approaches. An approach conducted under Instrument Flight Rules that authorizes the pilot to proceed visually and clear of clouds to the airport. Usually this will be used in conjunction with Visual Separation. When using Visual Separation, a pilot sees the other aircraft involved, and upon instructions from the controller, provides his own separation by manoeuvring his aircraft as necessary to avoid it. Visual Separation requires less spacing between aircraft than radar separation allowing more aircraft to land in a given period of time.
VFR Visual Flight Rules. Rules that govern the procedures for conducting flight under visual conditions. The term "VFR" is also used in the United States to indicate weather conditions that are equal to or greater than minimum VFR requirements. In addition, it is used by pilots and controllers to indicate a type of flight plan.
VOL Volume. Usually used to indicate that the volume of aircraft exceeds the airport's capacity.
VOR Very High Frequency Omni Directional Range. A ground-based electronic navigation aid transmitting very high frequency navigation signals, 360 degrees in azimuth, oriented from magnetic north. Used as the basis for navigation in the National Airspace System. The VOR periodically identifies itself by Morse Code and may have an additional voice identification feature. Voice features may be used by ATC or FSS for transmitting instructions/information to pilots.
VORTAC A navigation aid providing VOR azimuth, TACAN azimuth, and TACAN distance measuring equipment (DME) at one site.
VSBY

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Visibility. The ability, as determined by atmospheric conditions and expressed in units of distance, to see and identify prominent unlighted objects by day and prominent lighted objects by night.

 

WND Wind
WX Weather
WX DEV

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Weather Deviation

 

Z Zulu Time. Another term used to designate Coordinated Universal Time (UTC), the standard time common to every place in the world. Formerly and still widely called Greenwich Mean Time (GMT) and also World Time, UTC nominally reflects the mean solar time along the Earth's prime meridian.
ZAB Albuquerque Air Route Traffic Control Centre (ARTCC)
ZAU Chicago Air Route Traffic Control Centre (ARTCC)
ZBW Boston Air Route Traffic Control Centre (ARTCC)
ZDC Washington Air Route Traffic Control Centre (ARTCC)
ZFW Dallas-Ft Worth Air Route Traffic Control Center (ARTCC)
ZHU Houston Air Route Traffic Control Center (ARTCC)
ZID Indianapolis Air Route Traffic Control Centre (ARTCC)
ZJX Jacksonville Air Route Traffic Control Centre (ARTCC)
ZKC Kansas City Air Route Traffic Control Centre (ARTCC)
ZLA Los Angeles Air Route Traffic Control Centre (ARTCC)
ZLC Salt Lake City Air Route Traffic Control Centre (ARTCC)
ZMA Miami Air Route Traffic Control Centre (ARTCC)
ZME Memphis Air Route Traffic Control Centre (ARTCC)
ZMP Minneapolis Air Route Traffic Control Centre (ARTCC)
ZNY New York Air Route Traffic Control Centre (ARTCC)
ZOA Oakland Air Route Traffic Control Centre (ARTCC)
ZOB Cleveland Air Route Traffic Control Centre (ARTCC)
ZSE Seattle Air Route Traffic Control Centre (ARTCC)
ZTL Atlanta Air Route Traffic Control Centre (ARTCC)