AIRPORT ADVISORY AREA
The area within ten miles of an airport without a control tower or where the tower is not in operation, and on which a Flight Service Station is located. (See LOCAL AIRPORT ADVISORY.) (Refer to AIM.)

AIRPORT ARRIVAL RATE (AAR)
A dynamic input parameter specifying the number of arriving aircraft which an airport or airspace can accept from the ARTCC per hour. The AAR is used to calculate the desired interval between successive arrival aircraft.

AIRPORT DEPARTURE RATE (ADR)
A dynamic parameter specifying the number of aircraft which can depart an airport and the airspace can accept per hour.

AIRPORT DIAGRAM
The section of an instrument approach procedure chart that shows a detailed diagram of the airport. This diagram includes surface features and airport configuration information.

AIRPORT ELEVATION
The highest point of an airport’s usable runways measured in feet from mean sea level. (See TOUCHDOWN ZONE ELEVATION.) (See ICAO term AERODROME ELEVATION.)

AIRPORT LIGHTING
Various lighting aids that may be installed on an airport. Types of airport lighting include: a. Approach Light System

AIRPORT MARKING AIDS
Markings used on runway and taxiway surfaces to identify a specific runway, a runway threshold, a centerline, a hold line, etc. A runway should be marked in accordance with its present usage such as: a. Visual. b. Nonprecision instrument. c. Precision instrument. (Refer to AIM.)

AIRPORT REFERENCE POINT (ARP)
The approximate geometric center of all usable runway surfaces.

AIRPORT RESERVATION OFFICE
Office responsible for monitoring the operation of slot controlled airports. It receives and processes requests for unscheduled operations at slot controlled airports.

AIRPORT ROTATING BEACON
A visual NAVAID operated at many airports. At civil airports, Pilot/Controller Glossary 7/24/14 PCG A-9 alternating white and green flashes indicate the location of the airport. At military airports, the beacons flash alternately white and green, but are differentiated from civil beacons by dual peaked (two quick) white flashes between the green flashes. (See INSTRUMENT FLIGHT RULES.) (See SPECIAL VFR OPERATIONS.) (See ICAO term AERODROME BEACON.) (Refer to AIM.)

AIRPORT STREAM FILTER (ASF)
An on/off filter that allows the conflict notification function to be inhibited for arrival streams into single or multiple airports to prevent nuisance alerts.

AIRPORT SURFACE DETECTION EQUIPMENT (ASDE)
Surveillance equipment specifically designed to detect aircraft, vehicular traffic, and other objects, on the surface of an airport, and to present the image on a tower display. Used to augment visual observation by tower personnel of aircraft and/or vehicular movements on runways and taxiways.

AIRPORT SURVEILLANCE RADAR (ASR)
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.

AIRPORT SURVEILLANCE RADAR APPROACH
An instrument approach in which ATC issues instructions for pilot compliance based on aircraft position in relation to the final approach course and the distance from the end of the runway as displayed on the controller’s radar scope.

AIRPORT TAXI CHARTS
Designed to expedite the efficient and safe flow of ground traffic at an airport. These charts are identified by the official airport name; e.g., Ronald Reagan Washington National Airport. (See ICAO term AERONAUTICAL CHART.)

AIRPORT TRAFFIC CONTROL SERVICE
A service provided by a control tower for aircraft operating on the movement area and in the vicinity of an airport. (See MOVEMENT AREA.) (See TOWER.) (See ICAO term AERODROME CONTROL SERVICE.)

AIRPORT TRAFFIC CONTROL TOWER
(See TOWER.)

AIRPORT/FACILITY DIRECTORY
A publication designed primarily as a pilot’s operational manual containing all airports, seaplane bases, and heliports open to the public including communications data, navigational facilities, and certain special notices and procedures. This publication is issued in seven volumes according to geographical area.

AIRSPACE
The space above a certain geographical area.

AIRSPACE CONFLICT
Predicted conflict of an aircraft and active Special Activity Airspace (SAA).

AIRSPACE FLOW PROGRAM (AFP)
AFP is a Traffic Management (TM) process administered by the Air Traffic Control System Command Center (ATCSCC) where aircraft are assigned an Expect Departure Clearance Time (EDCT) in order to manage capacity and demand for a specific area of the National Airspace System (NAS). The purpose of the program is to mitigate the effects of en route constraints. It is a flexible program and may be implemented in various forms depending upon the needs of the air traffic system.

AIRSPACE HIERARCHY
Within the airspace classes, there is a hierarchy and, in the event of an overlap of airspace: Class A preempts Class B, Class B preempts Class C, Class C preempts Class D, Class D preempts Class E, and Class E preempts Class G.

AIRSPEED
The speed of an aircraft relative to its surrounding air mass. The unqualified term airspeed means one of the following: a.

AIRSPEED INDICATOR
A differential pressure gauge that measures the dynamic pressure of the air through which the aircraft is flying. Displays the craft’s airspeed, typically in knots, to the pilot.

AIRSTART
The starting of an aircraft engine while the aircraft is airborne, preceded by engine shutdown during training flights or by actual engine failure.

AIRWAY
A Class E airspace area established in the form of a corridor, the centerline of which is defined by radio navigational aids. (See FEDERAL AIRWAYS.) (See ICAO term AIRWAY.) (Refer to 14 CFR Part 71.) (Refer to AIM.)

AIRWAY [ICAO]
A control area or portion thereof established in the form of corridor equipped with radio navigational aids.

AIRWAY BEACON
Used to mark airway segments in remote mountain areas. The light flashes Morse Code to identify the beacon site. (Refer to AIM.)

AIRWORTHINESS
A state in which an aircraft or component meets the conditions of its type design and is in a condition for safe operation.

AIRWORTHINESS CERTIFICATE
A certificate issued by the FAA to aircraft that have been proven to meet the minimum standards set down by the Code of Federal Regulations.

AIRWORTHINESS DIRECTIVE (AD)
A regulatory notice sent out by the FAA to the registered owner of an aircraft informing the owner of a condition that prevents the aircraft from continuing to meet its conditions for airworthiness. Compliance with AD notes must be within the required time limit, and the fact of compliance, the date of compliance, and the method of compliance must be recorded in the aircraft’s maintenance records.

AIT
(See AUTOMATED INFORMATION TRANSFER.)

ALERFA (ALERT PHASE) [ICAO]
A situation wherein apprehension exists as to the safety of an aircraft and its occupants.

ALERT
An actual situation involving two real safety logic tracks (aircraft/aircraft, aircraft/vehicle, or aircraft/other tangible object) that safety logic has predicted will result in an imminent collision, based upon the current set of Safety Logic parameters. b.

ALERT AREA
(See SPECIAL USE AIRSPACE.)

ALERT NOTICE
A request originated by a flight service station (FSS) or an air route traffic control center (ARTCC) for an extensive communication search for overdue, unreported, or missing aircraft.

ALERTING SERVICE
A service provided to notify appropriate organizations regarding aircraft in need of search and rescue aid and assist such organizations as required.
ALMANAC DATA
Information the global positioning system (GPS) receiver can obtain from one satellite which describes the approximate orbital positioning of all satellites in the constellation. This information is necessary for the GPS receiver to know what satellites to look for in the sky at a given time.

ALNOT
(See ALERT NOTICE.)

ALONG
RACK DISTANCE.)

ALONG TRACK DISTANCE (ATD)
The distance measured from a point-in-space by systems using area navigation reference capabilities that are not subject to slant range errors.

ALPHANUMERIC DISPLAY
Letters and numerals used to show identification, altitude, beacon code, and other information concerning a target on a radar display. (See AUTOMATED RADAR TERMINAL SYSTEMS.)

ALS
See approach lighting system.
ALSF-1
Approach Light System with Sequenced Flashing Lights in ILS Cat-I configuration.
ALSF-2
Approach Light System with Sequenced Flashing Lights in ILS Cat-II configuration. The ALSF-2 may operate as an SSALR when weather conditions permit.

ALTERNATE AERODROME [ICAO]
An aerodrome to which an aircraft may proceed when it becomes either impossible or inadvisable to proceed to or to land at the aerodrome of intended landing. Note: The aerodrome from which a flight departs may also be an en-route or a destination alternate aerodrome for the flight.

ALTERNATE AIRPORT
An airport at which an aircraft may land if a landing at the intended airport becomes inadvisable. (See ICAO term ALTERNATE AERODROME.)

ALTERNATE STATIC SOURCE VALVE
A valve in the instrument static air system that supplies reference air pressure to the altimeter, airspeed indicator, and vertical speed indicator if the normal static pickup should become clogged or iced over.

ALTIMETER
An instrument that indicates flight altitude by sensing pressure changes and displaying alttude in feet or meters.

ALTIMETER SETTING
The barometric pressure reading used to adjust a pressure altimeter for variations in existing atmospheric pressure or to the standard altimeter setting (29.92). (Refer to 14 CFR Part 91.) (Refer to AIM.)

ALTITUDE
The height of a level, point, or object measured in feet Above Ground Level (AGL) or from Mean Sea Level (MSL). (See FLIGHT LEVEL.)

ALTITUDE [ICAO]
The vertical distance of a level, a point or an object considered as a point, measured from mean sea level (MSL).

ALTITUDE ENGINE
A reciprocating aircraft engine having a rated takeoff power that is producible from sea level to an established higher altitude.

ALTITUDE READOUT
An aircraft’s altitude, transmitted via the Mode C transponder feature, that is visually displayed in 100-foot increments on a radar scope having readout capability. (See ALPHANUMERIC DISPLAY.) (See AUTOMATED RADAR TERMINAL SYSTEMS.) (Refer to AIM.)

ALTITUDE RESERVATION
Airspace utilization under prescribed conditions normally employed for the mass movement of aircraft or other special user requirements which cannot otherwise be accomplished. ALTRVs are approved by the appropriate FAA facility. (See AIR TRAFFIC CONTROL SYSTEM COMMAND CENTER.)

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.

ALTITUDE RESTRICTIONS ARE CANCELED
Adherence to previously imposed altitude restrictions is no longer required during a climb or descent.

ALTRV
(See ALTITUDE RESERVATION.)

AMBIENT AIR
Air surrounding the outside of a balloon envelope.

AMBIENT PRESSURE
The pressure in the area immediately surrounding the aircraft.

AMBIENT TEMPERATURE
The temperature in the area immediately surrounding the aircraft.

AME
See aviation medical examiner.

AMENDMENT STATUS
The circulation date and revision number of an instrument approach procedure, printed above the procedure identification.

AMMETER
An instrument installed in series with an electrical load used to measure the amount of current flowing through the load.

AMPHIBIAN
A seaplane with retractable wheel-type landinggear that can be extended to allowlandings to be made on land.

AMPLITUDE
The maximum displacement of a wave.
AMVER
(See AUTOMATED MUTUAL-ASSISTANCE VESSEL RESCUE SYSTEM.)

AN/TPX
2 interrogator system currently installed in fixed RAPCONs. The PIDP detects, tracks, and predicts secondary radar aircraft targets. These are displayed by means of computer-generated symbols and alphanumeric characters depicting flight identification, aircraft altitude, ground speed, and flight plan data. Although primary radar targets are not tracked, they are displayed coincident with the secondary radar targets as well as with the other symbols and alphanumerics. The system has the capability of interfacing with ARTCCs.

ANABATIC WINDS
In weather, a wind that blows up the slope of a hill or mountain due to increased heating along the valley walls.

ANCHOR
A heavy hook connected to the seaplane by a line or cable, intended to dig into the bottom and keep the seaplane from drifting.

ANEROID
The sensitive component in an altimeter or barometer that measures the absolute pressure of the air. It is a sealed, flat capsule made of thin disks of corrugated metal soldered together and evacuated by pumping all of the air out of it.

ANEROID BAROMETER
An instrument that measures the absolute pressure of the atmosphere by balancing the weight of the air above it against the spring action of the aneroid.

ANGLE OF ATTACK
The angle between the airfoil’s chord line andthe relative wind.

ANGLE OF ATTACK (AOA)
The acute angle between the chord line of the airfoil and the direction of the relative wind.

ANGLE OF INCIDENCE
The angle formed by the chord line of the wing at the keel of a WSC and a line parallel to the longitudinal axis of the WSC carriage. The angle of incidence changes in the WSC controlled by the pilot.

ANHEDRAL
A downward slant from root to tip of an aircraft’s wing or horizontal tail surface.

ANNUAL INSPECTION
A complete inspection of an aircraft and engine, required by the Code of Federal Regulations, to be accomplished every 12 calendar months on all certificated aircraft. Only an A&P technician holding an Inspection Authorization can conduct an annual inspection.

ANTI-ICE
Preventing the accumulation of ice on an aircraft structure via a system designed for that purpose.

ANTISERVO TAB
An adjustable tab attached to the trailing edge of a stabilator that moves in the same direction as the primary control. It is used to make the stabilator less sensitive.

ANTITORQUE PEDAL
The pedal used to control the pitch of the tail rotor or air diffuser in a NOTAR® system.

ANTITORQUE ROTOR
See tail rotor.

ANXIETY
Mental discomfort that arises from the fear of anything, real or imagined. May have a potent effect on actions and the ability to learn from perceptions.

AOA
See angle of attack.

AOI
See aircraft operating instructions.

APB
(See AUTOMATED PROBLEM DETECTION BOUNDARY.)

APD
(See AUTOMATED PROBLEM DETECTION.)

APDIA
(See AUTOMATED PROBLEM DETECTION INHIBITED AREA.)

APEX LINE
A line attached to the top of most balloons to assist in inflation or deflation. Also called crown line or top handling line.

APPLICATION
A basic level of learning at which the student puts something to use that has been learned and understood.

APPLICATION STEP
The third step of the teaching process, where the student performs the procedure or demonstrates the knowledge required in the lesson. In the telling-and-doing technique of flight instruction, this step consists of the student doing the procedure while explaining it.

APPROACH
ATC authorization for an aircraft to execute a specific instrument approach procedure to an airport; e.g., “Cleared ILS Runway Three Six Approach.” (See APPROACH CLEARANCE.) (See INSTRUMENT APPROACH PROCEDURE.) (Refer to 14 CFR Part 91.) (Refer to AIM.)

APPROACH CLEARANCE
Authorization by ATC for a pilot to conduct an instrument approach. The type of instrument approach for which a clearance and other pertinent information is provided in the approach clearance when required. (See CLEARED APPROACH.) (See INSTRUMENT APPROACH PROCEDURE.) (Refer to AIM.) (Refer to 14 CFR Part 91.)

APPROACH CONTROL FACILITY
A terminal ATC facility that provides approach control service in a terminal area. (See APPROACH CONTROL SERVICE.) (See RADAR APPROACH CONTROL FACILITY.)

APPROACH CONTROL SERVICE
Air traffic control service provided by an approach control facility for arriving and departing VFR/IFR aircraft and, on occasion, en route aircraft. At some airports not served by an approach control facility, the ARTCC provides limited approach control service. (See ICAO term APPROACH CONTROL SERVICE.) (Refer to AIM.)

APPROACH CONTROL SERVICE [ICAO]
Air traffic control service for arriving or departing controlled flights.

APPROACH GATE
An imaginary point used within ATC as a basis for vectoring aircraft to the final approach course. The gate will be established along the final approach course 1 mile from the final approach fix on the side away from the airport and will be no closer than 5 miles from the landing threshold.

APPROACH HOLD AREA
The locations on taxiways in the approach or departure areas of a runway designated to protect landing or departing aircraft. These locations are identified by signs and markings.

APPROACH LIGHT SYSTEM
(See AIRPORT LIGHTING.)

APPROACH LIGHT SYSTEM (ALS)
An airport lighting facility which provides visual guidance to landing aircraft by radiating light beams in a directional pattern by which the pilot aligns the aircraft with the extended centerline of the runway on his/her final approach for landing. Condenser Discharge Sequential Flashing Lights/Sequenced Flashing Lights may be installed in conjunction with the ALS at some airports.

APPROACH LIGHTING SYSTEM (ALS)
Provides lights that will penetrate the atmosphere far enough from touchdown to give directional, distance, and glidepath information for safe transition from instrument to visual flight.

APPROACH SEQUENCE
The order in which aircraft are positioned while on approach or awaiting approach clearance. (See LANDING SEQUENCE.) (See ICAO term APPROACH SEQUENCE.)

APPROACH SEQUENCE [ICAO]
The order in which two or more aircraft are cleared to approach to land at the aerodrome.

APPROACH SPEED
The recommended speed contained in aircraft manuals used by pilots when making an approach to landing. This speed will vary for different segments of an approach as well as for aircraft weight and configuration.

APPROPRIATE ATS AUTHORITY [ICAO]
The relevant authority designated by the State responsible for providing air traffic services in the airspace concerned. In the United States, the appropriate ATS authority is the Program Director for Air Traffic Planning and Procedures, ATP-1.

APPROPRIATE AUTHORITY
a. Regarding flight over the high seas: the relevant authority is the State of Registry. b. Regarding flight over other than the high seas: the relevant authority is the State having sovereignty over the territory being overflown.

APPROPRIATE OBSTACLE CLEARANCE MINIMUM ALTITUDE
Any of the following: (See MINIMUM EN ROUTE IFR ALTITUDE.) (See MINIMUM IFR ALTITUDE.) (See MINIMUM OBSTRUCTION CLEARANCE ALTITUDE.) (See MINIMUM VECTORING ALTITUDE.)

APPROPRIATE TERRAIN CLEARANCE MINIMUM ALTITUDE
Any of the following: (See MINIMUM EN ROUTE IFR ALTITUDE.) (See MINIMUM IFR ALTITUDE.) (See MINIMUM OBSTRUCTION CLEARANCE ALTITUDE.) (See MINIMUM VECTORING ALTITUDE.)

APPROVED
Approved by the FAA Administrator or person authorized by the Administrator.

APRON
A defined area on an airport or heliport intended to accommodate aircraft for purposes of loading or unloading passengers or cargo, refueling, parking, or maintenance. With regard to seaplanes, a ramp is used for access to the apron from the water. (See ICAO term APRON.)

APRON [ICAO]
A defined area, on a land aerodrome, intended to accommodate aircraft for the purposes of loading or unloading passengers, mail or cargo, refueling, parking or maintenance.

ARC
The track over the ground of an aircraft flying at a constant distance from a navigational aid by reference to distance measuring equipment (DME).

ARCHIMEDES’ PRINCIPLE
The Greek mathematician’s principle of buoyancy, which states that an object (a balloon) immersed in a fluid (the air) loses as much of its own weight as the weight of the fluid it replaces.

AREA
Any water area designatedfor the landing of seaplanes.

AREA CHART
Part of the low-altitude en route chart series, this chart furnishes terminal data at a larger scale for congested areas.

AREA CONTROL CENTER [ICAO]
An air traffic control facility primarily responsible for ATC services being provided IFR aircraft during the en route phase of flight. The U.S. equivalent facility is an air route traffic control center (ARTCC).

AREA FORECAST (FA)
A report that gives a picture of clouds, general weather conditions, and visual meteorological conditions (VMC) expected over a large area encompassing several states.

AREA NAVIGATION (RNAV)
A method of navigation which permits aircraft operation on any desired flight path within the coverage of ground- or space-based navigation aids or within the limits of the capability of self-contained aids, or a combination of these. Note: Area navigation includes performance-based navigation as well as other operations that do not meet the definition of performance-based navigation. AREA NAVIGATION (RNAV) APPROACH CONFIGURATION: a.

AREA NAVIGATION (RNAV) APPROACH CONFIGURATION
See Standard T, Modified T, Standard I and TERMINAL ARRIVAL AREA (TAA)

AREA OF OPERATION
A phase of the practical test within the PTS.

ARINC
An acronym for Aeronautical Radio, Inc., a corporation largely owned by a group of airlines. ARINC is licensed by the FCC as an aeronautical station and contracted by the FAA to provide communications support for air traffic control and meteorological services in portions of international airspace.

ARM
The horizontal distance in inches from the reference datum line to the center of gravity of an item. Used in weight and loading calculations.

ARMY AVIATION FLIGHT INFORMATION BULLETIN
A bulletin that provides air operation data covering Army, National Guard, and Army Reserve aviation activities.

ARO
(See AIRPORT RESERVATION OFFICE.)

AROW
Certificates and documents required to be on board an aircraft to determine airworthiness: Airworthiness certificate, Registration certificate, Operating limitations, Weight and balance data.

ARRESTING SYSTEM
A safety device consisting of two major components, namely, engaging or catching devices and energy absorption devices.

ARRIVAL AIRCRAFT INTERVAL
An internally generated program in hundredths of minutes based upon the AAR. AAI is the desired optimum interval between successive arrival aircraft over the vertex.

ARRIVAL CENTER
The ARTCC having jurisdiction for the impacted airport.
ARRIVAL DELAY
A parameter which specifies a period of time in which no aircraft will be metered for arrival at the specified airport.

ARRIVAL SECTOR
An operational control sector containing one or more meter fixes.

ARRIVAL SECTOR ADVISORY LIST
An ordered list of data on arrivals displayed at the PVD/MDM of the sector which controls the meter fix.

ARRIVAL SEQUENCING PROGRAM
The automated program designed to assist in sequencing aircraft destined for the same airport.

ARRIVAL TIME
The time an aircraft touches down on arrival.

ARSR
(See AIR ROUTE SURVEILLANCE RADAR.)

ARTCC
(See AIR ROUTE TRAFFIC CONTROL CENTER.)

ARTICULATED ROTOR
A rotory stem in which each of the blades is connected to the rotor hub in such away that it is free to change its pitch angle, and move up and down and fore and aft in its plane of rotation.

ARTS
(See AUTOMATED RADAR TERMINAL SYSTEMS.)

ASDA
(See ACCELERATE-STOP DISTANCE AVAILABLE.)

ASDA [ICAO]
(See ICAO Term ACCELERATE-STOP DISTANCE AVAILABLE.)

ASDE
(See AIRPORT SURFACE DETECTION EQUIPMENT.)

ASDE 3
a Surface Movement Radar.

ASDE 3X
an ASDE X system that uses the ASDE 3 Surface Movement Radar.

ASDE X
a system that uses a X-band Surface Movement Radar and multilateration. Data from these two sources are fused and presented on a digital display.

ASF
(See AIRPORT STREAM FILTER.)

ASLAR
(See AIRCRAFT SURGE LAUNCH AND RECOVERY.)

ASOS
See Automated Surface Observing System.

ASOS/AWSS/AWOS ONER
(See OCEANIC NAVIGATIONAL ERROR REPORT.)

ASP
(See ARRIVAL SEQUENCING PROGRAM.)

ASPECT RATIO
Span of a wing divided by its average chord.

ASPECT RATION
The ratio between the wing span and the mean chord of the wing.

ASR
(See AIRPORT SURVEILLANCE RADAR.)

ASR APPROACH
(See SURVEILLANCE APPROACH.)

ASSOCIATED
A radar target displaying a data block with flight identification and altitude information. (See UNASSOCIATED.)

ASYMMETRIC THRUST
Also known as P-factor. A tendency for an aircraft to yaw to the left due to the descending propeller blade on the right producing more thrust than the ascending blade on the left. This occurs when the aircraft’s longitudinal axis is in a climbing attitude in relation to the relative wind. The P-factor would be to the right if the aircraft had a counterclockwise rotating propeller.

ASYMMETRICAL AIRFOIL
An airfoil section that is not the same on both sides of the chord line.

AT (ALTITUDE)
Used by ATC when a specific altitude restriction at a specified fix is required. CROSS (FIX)

AT OR ABOVE (ALTITUDE)
Used by ATC when an altitude restriction at a specified fix is required. It does not prohibit the aircraft from crossing the fix at a higher altitude than specified; however, the higher altitude may not be one that will violate a succeeding altitude restriction or altitude assignment. (See ALTITUDE RESTRICTION.) (Refer to AIM.) CROSS (FIX)

AT OR BELOW (ALTITUDE)
Used by ATC when a maximum crossing altitude at a specific fix is required. It does not prohibit the aircraft from crossing the fix at a lower altitude; however, it must be at or above the minimum IFR altitude. (See ALTITUDE RESTRICTION.) (See MINIMUM IFR ALTITUDES.) (Refer to 14 CFR Part 91.)

ATC
Air traffic control.

ATC ADVISES
Used to prefix a message of noncontrol information when it is relayed to an aircraft by other than an air traffic controller. (See ADVISORY.)

ATC ASSIGNED AIRSPACE
Airspace of defined vertical/lateral limits, assigned by ATC, for the purpose of providing air traffic segregation between the specified activities being conducted within the assigned airspace and other IFR air traffic. (See SPECIAL USE AIRSPACE.)

ATC CLEARANCE
(See AIR TRAFFIC CLEARANCE.)

ATC CLEARS
Used to prefix an ATC clearance when it is relayed to an aircraft by other than an air traffic controller.

ATC FILED EN ROUTE DELAY
Any of the following preplanned delays at points/areas along the route of flight which require special flight plan filing and handling techniques. a. Terminal Area Delay. A delay within a terminal area for touch-and-go, low approach, or other terminal area activity. b. Special Use Airspace Delay. A delay within a Military Operations Area, Restricted Area, Warning Area, or ATC Assigned Airspace. c. Aerial Refueling Delay. A delay within an Aerial Refueling Track or Anchor.

ATC FLY-BY WAYPOINT
A fly-by waypoint requires the use of turn anticipation to avoid overshoot of the next flight segment.

ATC INSTRUCTIONS
Directives issued by air traffic control for the purpose of requiring a pilot to take specific actions; e.g., “Turn left heading two five zero,” “Go around,” “Clear the runway.” (Refer to 14 CFR Part 91.)

ATC PREFERRED ROUTE NOTIFICATION
URET notification to the appropriate controller of the need to determine if an ATC preferred route needs to be applied, based on destination airport. (See ROUTE ACTION NOTIFICATION.) (See USER REQUEST EVALUATION TOOL.)

ATC PREFERRED ROUTES
Preferred routes that are not automatically applied by Host.

ATC REQUESTS
Used to prefix an ATC request when it is relayed to an aircraft by other than an air traffic controller.

ATC SECURITY SERVICES
Communications and security tracking provided by an ATC facility in support of the DHS, the DOD, or other Federal security elements in the interest of national security. Such security services are only applicable within designated areas. ATC security services do not include ATC basic radar services or flight following.

ATC SECURITY SERVICES POSITION
The position responsible for providing ATC security services as defined. This position does not provide ATC, IFR separation, or VFR flight following services, but is responsible for providing security services in an area comprising airspace assigned to one or more ATC operating sectors. This position may be combined with control positions.

ATC SECURITY TRACKING
The continuous tracking of aircraft movement by an ATC facility in support of the DHS, the DOD, or other security elements for national security using radar (i.e., radar tracking) or other means (e.g., manual tracking) without providing basic radar services (including traffic advisories) or other ATC services not defined in this section.

ATC TORA
(See TAKEOFF RUN AVAILABLE.) (See ICAO term TAKEOFF RUN AVAILABLE.)

ATCAA
(See ATC ASSIGNED AIRSPACE.)

ATCRBS
(See RADAR.)

ATCSCC
(See AIR TRAFFIC CONTROL SYSTEM COMMAND CENTER.)

ATCSCC INTERNATIONAL AIRPORT
Relating to international flight, it means: a. An airport of entry which has been designated by the Secretary of Treasury or Commissioner of Customs as an international airport for customs service. b. A landing rights airport at which specific permission to land must be obtained from customs authorities in advance of contemplated use. c. Airports designated under the Convention on International Civil Aviation as an airport for use by international commercial air transport and/or international general aviation. (See ICAO term INTERNATIONAL AIRPORT.) (Refer to AIRPORT/FACILITY DIRECTORY.) (Refer to IFIM.)

ATCT
(See TOWER.)

ATIS
(See AUTOMATIC TERMINAL INFORMATION SERVICE.)

ATIS [ICAO]
(See ICAO Term AUTOMATIC TERMINAL INFORMATION SERVICE.)

ATMOSPHERIC PROPAGATION DELAY
A bending of the electromagnetic (EM) wave from the satellite that creates an error in the GPS system.

ATMOSPHERIC SOUNDING
A measure of atmospheric variables aloft, usually pressure, temperature, humidity, and wind.

ATMOSPHERIC STABILITY
Describes a state in which an air parcel resists vertical displacement or, once displaced (forinstance by flow over a hill), tends to return to its original level.

ATP-1 APPROPRIATE AUTHORITY
a. Regarding flight over the high seas: the relevant authority is the State of Registry. b. Regarding flight over other than the high seas: the relevant authority is the State having sovereignty over the territory being overflown.

ATS ROUTE [ICAO]
A specified route designed for channeling the flow of traffic as necessary for the provision of air traffic services. Note: The term “ATS Route” is used to mean variously, airway, advisory route, controlled or uncontrolled route, arrival or departure, etc. ATTENTION ALL USERS PAGE (AAUP)- The AAUP provides the pilot with additional information relative to conducting a specific operation, for example, PRM approaches and RNAV departures.

ATTITUDE
A personal motivational predisposition to respond to persons, situations, or events in a given manner that can, nevertheless, be changed or modified through training as a sort of mental shortcut to decision-making.

ATTITUDE AND HEADING REFERENCE SYSTEM (AHRS)
A system composed of three-axis sensors that provide heading, attitude, and yaw information for aircraft. AHRS are designed to replace traditional mechanical gyroscopic flight instruments and provide superior reliability and accuracy.

ATTITUDE DIRECTOR INDICATOR (ADI)
An aircraft attitude indicator that incorporates flight command bars to provide pitch and roll commands.

ATTITUDE INDICATOR
The foundation for all instrument flight, this instrument reflects the airplane’s attitude in relation to the horizon.

ATTITUDE INSTRUMENT FLYING
Controlling the aircraft by reference to the instruments rather than by outside visual cues.

ATTITUDE MANAGEMENT
The ability to recognize one’s own hazardous attitudes and the willingness to modify them as necessary through the application of appropriate antidotal thoughts.

ATTITUDE MANAGEMENT OF PILOT
The ability to recognize hazardous attitudes in oneself and the willingness to modify them as necessary through the application of an appropriate antidote thought.

ATTITUDE OF PILOT
A personal motivational predisposition to respond to persons, situations, or events in a given mannerthat can, nevertheless, be changed or modified through training as sort of a mental shortcut to decision-making.

AUTHENTIC ASSESSMENT
An assessment in which the student is asked to perform real-world tasks, and demonstrate a meaningful application of skills and competencies.


                                                                 


                                                                        Click to continue for the letter “A”