JEPPESEN GENERAL AIRWAY MANUAL (Issue Date 1 JUL 21)

NEAR-PARALLEL RUNWAYS — Non-intersecting runways whose extended centre lines have
an angle of convergence/divergence of 15 degrees or less.
NON PRECISION APPROACH (NPA) PROCEDURE — [see INSTRUMENT APPROACH PRO-
CEDURE (IAP)]
NO PROCEDURE TURN (NoPT) — No procedure turn is required nor authorized.
NORMAL OPERATING ZONE (NOZ) — Airspace of defined dimensions extending to either side
of an ILS localizer course and/or MLS final approach track. Only the inner half of the normal oper-
ating zone is taken into account in independent parallel approaches.
NOTAM (ICAO) — A notice distributed by means of telecommunication containing information
concerning the establishment, condition or change in any aeronautical facility, service, procedure
or hazard, the timely knowledge of which is essential to personnel concerned with flight opera-
tions.
NO-TRANSGRESSION ZONE (NTZ) — In the context of independent parallel approaches, a cor-
ridor of airspace of defined dimensions located centrally between the two extended runway centre
lines, where a penetration by an aircraft requires a controller intervention to manoeuvre any
threatened aircraft on the adjacent approach.
OBSERVATION (METEOROLOGICAL) — The evaluation of one or more meteorological ele-
ments.
OBSTACLE ASSESSMENT SURFACE (OAS) — A defined surface intended for the purpose of
determining those obstacles to be considered in the calculation of obstacle clearance altitude/
height for a specific APV or precision approach procedure.
OBSTACLE CLEARANCE ALTITUDE (OCA) OR OBSTACLE CLEARANCE HEIGHT (OCH) —
The lowest altitude or the lowest height above the elevation of the relevant runway threshold or
the aerodrome elevation as applicable, used in establishing compliance with appropriate obstacle
clearance criteria.
NOTE 1: Obstacle clearance altitude is referenced to mean sea level and obstacle clearance
height is referenced to the threshold elevation or in the case of non-precision approaches to the
aerodrome elevation or the threshold elevation if that is more than 7ft (2m) below the aerodrome
elevation. An obstacle clearance height for a circling approach is referenced to the aerodrome
elevation.
NOTE 2: For convenience when both expressions are used they may be written in the form
“obstacle clearance altitude/height” and abbreviated “OCA/H.”
OBSTACLE FREE ZONE (OFZ) (ICAO) — The airspace above the inner approach surface, inner
transitional surfaces, and balked landing surface and that portion of the strip bounded by these
surfaces, which is not penetrated by any fixed obstacle other than a low-mass and frangibly
mounted one required for air navigation purposes.
OBSTRUCTION CLEARANCE LIMIT (OCL) — The height above aerodrome elevation below
which the minimum prescribed vertical clearance cannot be maintained either on approach or in
the event of a missed approach.

DEFINITIONS AND ABBREVIATIONS

GLOSSARY

OPERATIONAL CONTROL — The exercise of authority over the initiation, continuation, diver-
sion or termination of a flight in the interest of the safety of the aircraft and the regularity and effi-
ciency of the flight.
OPERATOR — A person, organization or enterprise engaged in or offering to engage in an air-
craft operation.
PILOT CONTROLLED LIGHTING (PCL) (USA) — (For other states see Air Traffic Control Rules
and Procedures.)
Radio control of lighting is available at selected airports to provide airborne control of lights by
keying the aircraft’s microphone. The control system consists of a 3-step control responsive to 7,
5, and/or 3 microphone clicks. The 3-step and 2-step lighting facilities can be altered in intensity.
All lighting is illuminated for a period of 15min (except for 1-step and 2-step REILs which may be
turned off by keying the mike 5 or 3 times, respectively).
Suggested use is to always initially key the mike 7 times; this assures that all controlled lights are
turned on to the maximum available intensity. If desired, adjustment can then be made, where the
capability is provided, to a lower intensity (or the REIL turned off) by keying the mike 5 and/or
three times. Approved lighting systems may be activated by keying the mike as indicated below:

KEY MIKE

FUNCTION

7 times within 5 seconds

Highest intensity available

5 times within 5 seconds

Medium or lower intensity (Lower REIL or REIL Off)

3 times within 5 seconds

Lowest intensity available (Lower REIL or REIL Off)

Due to the close proximity of airports using the same frequency, radio controlled lighting receivers
may be set at a low sensitivity requiring the aircraft to be relatively close to activate the system.
Consequently, even when lights are on, always key mike as directed when overflying an airport of
intended landing or just prior to entering the final segment of an approach. This will assure the
aircraft is close enough to activate the system and a full 15min lighting duration is available.
PILOT-IN-COMMAND (PIC) — The pilot responsible for the operation and safety of the aircraft
during flight time.
PITCH POINT — A fix/waypoint that serves as a transition point from a departure procedure or
the low altitude ground-based navigation structure into the high altitude waypoint system.
POINT-IN-SPACE APPROACH (PinS) — The point-in-space approach is based on a basic
GNSS non-precision approach procedure designed for helicopters only. It is aligned with a refer-
ence point located to permit subsequent flight manoeuvring or approach and landing using visual
manoeuvring in adequate visual conditions to see and avoid obstacles.
POINT-IN-SPACE REFERENCE POINT (PRP) — Reference point for the point-in-space
approach as identified by the latitude and longitude of the MAPt.
PRECISION APPROACH (PA) PROCEDURE — [see INSTRUMENT APPROACH PROCE-
DURE (IAP)].

DEFINITIONS AND ABBREVIATIONS

GLOSSARY

PRECISION APPROACH RADAR (PAR) — Primary radar equipment used to determine the
position of an aircraft during final approach, in terms of lateral and vertical deviations relative to a
nominal approach path, and in range relative to touchdown.
NOTE: Precision approach radars are designated to enable pilots of aircraft to be given guidance
by radio communication during the final stages of the approach to land.
PRECISION OBJECT FREE ZONE (POFZ) (FAA) — A volume of airspace above an area begin-
ning at the runway threshold, at the threshold elevation, and entered on the extended runway
centerline. The standard POFZ is 200ft (60m) long and 800ft (240m) wide. The POFZ must be
kept clear when an aircraft on a vertically guided final approach is within two nautical miles (NM)
of the runway threshold and the reported ceiling is below 250ft and/or visibility less than ¾ statute
miles (SM) (or runway visual range below 4000ft). The POFZ is considered clear even if the wing
of the aircraft holding on a taxiway waiting for runway clearance penetrates the POFZ; however,
neither the fuselage nor the tail may infringe on the POFZ. For approaching aircraft, in the event
that a taxiing/parked aircraft or vehicle is not clear of the POFZ, air traffic control will provide advi-
sories to the approaching aircraft regarding the position of the offending aircraft/vehicle. In this
case the pilot of the approaching aircraft must decide to continue or abort the approach. When the
reported ceiling is below 800ft or visibility less than 2SM, departing aircraft must do the following.
When there is an air traffic control tower (ATCT) in operation, plan to hold at the ILS hold line and
hold as directed by air traffic control. When there is no operating ATCT, honor the ILS hold line
and do not taxi into position and take-off if there is an approaching aircraft within 2NM of the
runway threshold.
PRE-DEPARTURE CLEARANCE (PDC) — An automated Clearance Delivery system relaying
ATC departure clearances from the FAA to the user network computer for subsequent delivery to
the cockpit via ACARS (Airline/Aviation VHF data link) where aircraft are appropriately equipped,
or to gate printers for pilot pickup.
PRESSURE ALTITUDE — An atmospheric pressure expressed in terms of altitude which corre-
sponds to that pressure in the Standard Atmosphere.
PREVAILING VISIBILITY — The greatest visibility value, observed in accordance with the defini-
tion “visibility”, which is reached within at least half the horizon circle or within at least half of the
surface of the aerodrome. These areas could comprise contiguous or non-contiguous sectors.
NOTE: This value may be assessed by human observation and/or instrumented systems. When
instruments are installed, they are used to obtain the best estimate of the prevailing visibility.
PRIMARY AREA — A defined area symmetrically disposed about the nominal flight track in
which full obstacle clearance is provided. (See also

SECONDARY AREA.)

PRIMARY RADAR — A radar system which uses reflected radio signals.
PRIMARY SURVEILLANCE RADAR (PSR) — A surveillance radar system which uses reflected
radio signals.
PROCEDURE ALTITUDE/HEIGHT — Are recommended altitudes/heights developed in coordi-
nation with Air Traffic Control requirements flown operationally at or above the minimum altitude/
height and established to accommodate a stabilized descent at a prescribed descent gradient/

DEFINITIONS AND ABBREVIATIONS

GLOSSARY

angle in the intermediate/final approach segment. Procedure altitudes/heights are never below
the Segment Minimum Altitude (SMA) or Segment Minimum Safe Altitude (SMSA).
PROCEDURE TURN (PT) (ICAO) — A maneuver in which a turn is made away from a designa-
ted track followed by a turn in the opposite direction to permit the aircraft to intercept and proceed
along the reciprocal of the designated track.
NOTE 1: Procedure turns are designated “left” or “right” according to the direction of the initial
turn.
NOTE 2: Procedure turns may be designated as being made either in level flight or while
descending, according to the circumstances of each individual procedure.
PROCEDURE TURN (PT) (USA) — The maneuver prescribed when it is necessary to reverse
direction to establish an aircraft on the intermediate approach segment or final approach course.
The outbound course, direction of turn, distance within which the turn must be completed, and
minimum altitude are specified in the procedure. However, unless otherwise restricted, the point
at which the turn may be commenced and the type and rate of turn are at the discretion of the
pilot.
PROCEDURE TURN INBOUND — That point of a procedure turn maneuver where course rever-
sal has been completed and an aircraft is established inbound on the intermediate approach seg-
ment or final approach course. A report of “procedure turn inbound” is normally used by ATC as a
position report for separation purposes.
PROFILE — The orthogonal projection of a flight path or portion thereof on the vertical surface
containing the nominal track.
PROGNOSTIC CHART — A forecast of a specified meteorological element(s) for a specified time
or period and a specified surface or portion of airspace, depicted graphically on a chart.
PROHIBITED AREA (ICAO) (USA) — [see SPECIAL USE AIRSPACE (SUA)].
QFE — [see ALTIMETER SETTING]
QNE — [see ALTIMETER SETTING]
QNH — [see ALTIMETER SETTING]
RACETRACK PROCEDURE (ICAO) — A procedure designed to enable the aircraft to reduce
altitude during the initial approach segment and/or establish the aircraft inbound when the entry
into a reversal procedure is not practical.
RADAR — A radio detection device which provides information on range, azimuth and/or eleva-
tion of objects.
RADAR APPROACH — An approach, executed by an aircraft, under the direction of a radar con-
troller.
RADAR CONTACT — The situation which exists when the radar position of a particular aircraft is
seen and identified on a radar display.

DEFINITIONS AND ABBREVIATIONS

100

GLOSSARY

RADAR SEPARATION — The separation used when aircraft position information is derived from
radar sources.
RADAR WEATHER ECHO INTENSITY LEVELS — Existing radar systems cannot detect turbu-
lence. However, there is a direct correlation between the degree of turbulence and other weather
features associated with thunderstorms and the radar weather echo intensity. The National
Weather Service has categorized radar weather echo intensity for precipitation into six levels.
These levels are sometimes expressed during communications as “VIP LEVEL” 1 through 6
(derived from the component of the radar that produces the information — Video Integrator and
Processor). The following list gives the “VIP LEVELS” in relation to the precipitation intensity
within a thunderstorm:

Level 1.
Level 2.
Level 3.
Level 4.
Level 5.
Level 6.

WEAK
MODERATE
STRONG
VERY STRONG
INTENSE
EXTREME

RADIO ALTIMETER / RADAR ALTIMETER — Aircraft equipment which makes use of the reflec-
tion of radio waves from the ground to determine the height of the aircraft above the surface.
RADIOTELEPHONY — A form of radio communication primarily intended for the exchange of
information in the form of speech.
RADIOTELEPHONY NETWORK — A group of radiotelephony aeronautical stations which oper-
ate on and guard frequencies from the same family and which support each other in a defined
manner to ensure maximum dependability of air-ground communications and dissemination of air-
ground traffic.
REDUCED VERTICAL SEPARATION MINIMUMS (RVSM) — A reduction in the vertical separa-
tion between FL290 – FL410 from 2000ft to 1000ft.
REGIONAL AIR NAVIGATION AGREEMENT — Agreement approved by the Council of ICAO
normally on the advice of a regional air navigation meeting.
REPETITIVE FLIGHT PLAN (RPL) — A flight plan related to a series of frequently recurring, reg-
ularly operated individual flights with identical basic features, submitted by an operator for reten-
tion and repetitive use by ATS units.
REPORTING POINT — A specified geographical location in relation to which the position of an
aircraft can be reported.
REQUIRED NAVIGATION PERFORMANCE (RNP) — A statement of navigation position accu-
racy necessary for operation within a defined airspace. RNP is performance-based and not
dependent on a specific piece of equipment. RNP includes a descriptive number, the value being
an indicator of the size of the containment area (e.g., RNP-0.3, RNP-1, RNP-3, etc.). The different

DEFINITIONS AND ABBREVIATIONS

101

GLOSSARY

values are assigned to terminal, departure, and enroute operations. Some aircraft have RNP
approval in their AFM without a GPS sensor. The lowest level of sensors that the FAA will support
for RNP service is DME/DME. However, necessary DME signal may not be available at the air-
port of intended operations. For those locations having an RNAV chart published with LNAV/
VNAV minimums, a procedure note may be provided such as "DME/DME RNP-0.3 NA." This
means that RNP aircraft dependent on DME/DME to achieve RNP-0.3 are not authorized to con-
duct this approach. Where DME facility availability is a factor, the note may read "DME/DME
RNP-0.3 authorized; ABC and XYZ required." This means that ABC and XYZ facilities have been
determined by flight inspection to be required in the navigation solution to assure RNP-0.3.
VOR/DME updating must not be used for approach procedures.
RESCUE COORDINATION CENTER — A unit responsible for promoting efficient organization of
search and rescue service and for coordinating the conduct of search and rescue operations
within a search and rescue region.
RESCUE UNIT — A unit composed of trained personnel and provided with equipment suitable for
the expeditious conduct of search and rescue.
RESTRICTED AREA (ICAO) (USA) — [see SPECIAL USE AIRSPACE (SUA)].
REVERSAL PROCEDURE — A procedure designed to enable aircraft to reverse direction during
the initial approach segment of an instrument approach procedure. The sequence may include
procedure turns or base turns.
REVISION DATE — Charts revisions are issued on Fridays. Charts are considered effective
(usable) upon receipt. With regard to the coverages, charts are issued weekly or bi-weekly.
RNAV APPROACH — An instrument approach procedure which relies on aircraft area navigation
equipment for navigation guidance.
RNP TYPE — A containment value expressed as a distance in nautical miles from the intended
position within which flights would be for at least 95 percent of the total flying time.
EXAMPLE: RNP 4 represents a navigation accuracy of plus or minus 7.4km (4NM) on a 95 per-
cent containment basis.
ROUTE MINIMUM OFF-ROUTE ALTITUDE (Route MORA) — This is an altitude derived by Jep-
pesen. The Route MORA altitude provides reference point clearance within 10NM of the route
centerline (regardless of the route width) and end fixes. Route MORA values clear all reference
points by 1000ft in areas where the highest reference points are 5000ft MSL or lower. Route
MORA values clear all reference points by 2000ft in areas where the highest reference points are
5001ft MSL or higher. When a Route MORA is shown along a route as “unknown” it is due to
incomplete or insufficient information.
RUNWAY — A defined rectangular area on a land aerodrome prepared for the landing and take-
off of aircraft.
RUNWAY EDGE LIGHTS (ICAO) — Are provided for a runway intended for use at night or for a
precision approach runway intended for use by day or night. Runway edge lights shall be fixed
lights showing variable white, except that:

DEFINITIONS AND ABBREVIATIONS

102

GLOSSARY

a. in the case of a displaced threshold, the lights between the beginning of the runway and the

displaced threshold shall show red in the approach direction; and

b. a section of the lights 600m or one-third of the runway length, whichever is the less, at the

remote end of the runway from the end at which the take-off run is started, may show yellow.

RUNWAY EDGE LIGHTS (USA) — Lights used to outline the edges of runways during periods of
darkness or restricted visibility conditions. The light systems are classified according to the inten-
sity or brightness they are capable of producing: they are the High Intensity Runway Lights
(HIRL), Medium Intensity Runway Lights (MIRL), and the Low Intensity Runway Lights (RL). The
HIRL and MIRL systems have variable intensity controls, where the RLs normally have one inten-
sity setting.

a. The runway edge lights are white, except on instrument runways amber replaces white on

the last 2000ft or half of the runway length, whichever is less, to form a caution zone for
landings.

b. The lights marking the ends of the runway emit red light toward the runway to indicate the

end of runway to a departing aircraft and emit green outward from the runway end to indicate
the threshold to landing aircraft.

RUNWAY HOLDING POSITION — A designated position intended to protect a runway, an obsta-
cle limitation surface, or an ILS/MLS critical/sensitive area at which taxiing aircraft and vehicles
shall stop and hold, unless otherwise authorized by the aerodrome control tower.
NOTE: In radiotelephony phraseologies, the expression “holding point” is used to designate the
runway holding position.
RUNWAY INCURSION — Any occurrence at an aerodrome involving the incorrect presence of
an aircraft, vehicle or person on the protected area of a surface designated for the landing and
take-off of aircraft.
RUNWAY MARKINGS —

a. Basic marking — Markings on runways used for operations under visual flight rules consist-

ing of centerline markings and runway direction numbers and, if required, letters.

b. Instrument marking — Markings on runways served by nonvisual navigation aids and inten-

ded for landings under instrument weather conditions, consisting of basic marking plus
threshold markings.

c. All-weather (precision instrument) marking — Marking on runways served by nonvisual preci-

sion approach aids and on runways having special operational requirements, consisting of
instrument markings plus landing zone markings and side strips.

RUNWAY STRIP — A defined area including the runway and stopway, if provided, intended:

a. to reduce the risk of damage to aircraft running off a runway; and
b. to protect aircraft flying over it during take-off or landing operations.

DEFINITIONS AND ABBREVIATIONS

103

GLOSSARY

RUNWAY VISUAL RANGE (RVR) — The range over which the pilot of an aircraft on the centre
line of a runway can see the runway surface markings or the lights delineating the runway or iden-
tifying its centre line.
SAFETY-SENSITIVE PERSONNEL — Persons who might endanger aviation safety if they per-
form their duties and functions improperly including, but not limited to, crew members, aircraft
maintenance personnel and air traffic controllers.
SEARCH AND RESCUE SERVICES UNIT — A generic term meaning, as the case may be,
rescue coordination center, rescue subcenter or alerting post.
SECONDARY AREA — A defined area on each side of the primary area located along the nomi-
nal flight track in which decreasing obstacle clearance is provided. (See also

PRIMARY AREA).

SECONDARY RADAR — A radar system wherein a radio signal transmitted from a radar station
initiates the transmission of a radio signal from another station.
SECONDARY SURVEILLANCE RADAR (SSR) — A surveillance radar system which uses trans-
mitters/receivers (interrogators) and transponders.
SEGMENT MINIMUM ALTITUDE (SMA), or SEGMENT MINIMUM SAFE ALTITUDE (SMSA) —
An altitude that provides minimum obstacle clearance in each segment of a non-precision
approach. Segment minimum (safe) altitudes can be considered “do not descend below” altitudes
and can be lower than procedure altitudes which are specifically developed to facilitate a constant
rate or stabilized descent.
SEGMENTS OF AN INSTRUMENT APPROACH PROCEDURE — An instrument approach pro-
cedure may have as many as four separate segments depending on how the approach procedure
is structured.
ICAO —

a. Initial Approach — That segment of an instrument approach procedure between the initial

approach fix and the intermediate approach fix or, where applicable, the final approach fix or
point.

b. Intermediate Approach — That segment of an instrument approach procedure between

either the intermediate approach fix and the final approach fix or point, or between the end of
a reversal, race track or dead reckoning track procedure and the final approach fix or point,
as appropriate.

c. Final Approach — That segment of an instrument approach procedure in which alignment

and descent for landing are accomplished.

d. Missed Approach Procedure — The procedure to be followed if the approach cannot be con-

tinued.

USA —

a. Initial Approach — The segment between the initial approach fix and the intermediate fix or

the point where the aircraft is established on the intermediate course or final course.

DEFINITIONS AND ABBREVIATIONS

104

GLOSSARY

b. Intermediate Approach — The segment between the intermediate fix or point and the final

approach fix.

c. Final Approach — The segment between the final approach fix or point and the runway, air-

port or missed approach point.

d. Missed Approach — The segment between the missed approach point, or point of arrival at

decision height, and the missed approach fix at the prescribed altitude.

SEGREGATED PARALLEL OPERATIONS — Simultaneous operations on parallel or near-paral-
lel instrument runways in which one runway is used exclusively for approaches and the other
runway is used exclusively for departures.
SELECTIVE CALL SYSTEM (SELCAL) — A system which permits the selective calling of indi-
vidual aircraft over radiotelephone channels linking a ground station with the aircraft.
SHORELINE — A line following the general contour of the shore, except that in cases of inlets or
bays less than 30NM in width, the line shall pass directly across the inlet or bay to intersect the
general contour on the opposite side.
SIDESTEP MANEUVER — A visual maneuver accomplished by a pilot at the completion of an
instrument approach to permit a straight-in landing on a parallel runway not more than 1200ft to
either side of the runway to which the instrument approach was conducted.
SIGMET INFORMATION — Information issued by a meteorological watch office concerning the
occurrence or expected occurrence of specified en route weather phenomena which may affect
the safety of aircraft operations.
SIGNAL AREA — An area on an aerodrome used for the display of ground signals.
SIGNIFICANT POINT — A specified geographical location used in defining an ATS route or the
flight path of an aircraft and for other navigation and ATS purposes.
NOTE: There are three categories of significant points: ground-based navigation aid, intersection
and waypoint. In the context of this definition, intersection is a significant point expressed as radi-
als, bearings and/or distances from ground-based navigation aids.
SLUSH — Water-saturated snow which with a heel-and-toe slap-down motion against the ground
will be displaced with a splatter; specific gravity: 0.5 up to 0.8.
NOTE: Combinations of ice, snow and/or standing water may, especially when rain, rain and
snow, or snow is falling, produce substances with specific gravities in excess of 0.8. These sub-
stances, due to their high water/ice content, will have a transparent rather than a cloudy appear-
ance and, at the higher specific gravities, will be readily distinguishable from slush.
SNOW (on the ground) —

a. Dry snow. Snow which can be blown if loose or, if compacted by hand, will fall apart upon

release; specific gravity: up to but not including 0.35.

b. Wet snow. Snow which, if compacted by hand, will stick together and tend to or form a snow-

ball; specific gravity: 0.35 up to but not including 0.5.

DEFINITIONS AND ABBREVIATIONS

105

GLOSSARY

c. Compacted snow. Snow which has been compressed into a solid mass that resists further

compression and will hold together or break up into lumps if picked up; specific gravity: 0.5
and over.

SPECIAL USE AIRSPACE — Airspace of defined dimensions identified by an area on the sur-
face of the earth wherein activities must be confined because of their nature and/or wherein limi-
tations may be imposed upon aircraft operations that are not a part of those activities. Types of
special use airspace are:

a. Alert Area (USA) — Airspace which may contain a high volume of pilot training activities or

an unusual type of aerial activity, neither of which is hazardous to aircraft. Alert Areas are
depicted on aeronautical charts for the information of nonparticipating pilots. All activities
within an Alert Area are conducted in accordance with Federal Aviation Regulations, and
pilots of participating aircraft as well as pilots transiting the area are equally responsible for
collision avoidance.

b. Controlled Firing Area (USA) — Airspace wherein activities are conducted under conditions

so controlled as to eliminate hazards to non participating aircraft and to ensure the safety of
persons and property on the ground.

c. Danger Area (ICAO) — An airspace of defined dimensions within which activities dangerous

to the flight of aircraft may exist at specified times.

d. Military Operations Area (MOA) (USA) — A MOA is airspace established outside of a Class

“A” airspace area to separate or segregate certain nonhazardous military activities from IFR
traffic and to identify for VFR traffic where these activities are conducted.

e. Prohibited Area (ICAO) — An airspace of defined dimensions, above the land areas or terri-

torial waters of a State, within which the flight of aircraft is prohibited.
Prohibited Area (USA) — Airspace designated under FAR Part 73 within which no person
may operate an aircraft without the permission of the using agency.

f. Restricted Area (ICAO) — An airspace of defined dimensions, above the land areas or terri-

torial waters of a State, within which the flight of aircraft is restricted in accordance with cer-
tain specified conditions.
Restricted Area (USA) — Airspace designated under Part 73, within which the flight of air-
craft, while not wholly prohibited, is subject to restriction. Most restricted areas are designa-
ted joint use and IFR/VFR operations in the area may be authorized by the controlling ATC
facility when it is not being utilized by the using agency. Restricted areas are depicted on
enroute charts. Where joint use is authorized, the name of the ATC controlling facility is also
shown.

g. Warning Area (USA) — A warning area is airspace of defined dimensions from 3NM outward

from the coast of the United States, that contains activity that may be hazardous to nonparti-
cipating aircraft. The purpose of such warning areas is to warn nonparticipating pilots of the
potential danger. A warning area may be located over domestic or international waters or
both.

DEFINITIONS AND ABBREVIATIONS

106

GLOSSARY

SPECIAL VFR FLIGHT — A VFR flight cleared by air traffic control to operate within a control
zone in meteorological conditions below VMC.
STANDARD INSTRUMENT ARRIVAL (STAR) (ICAO) — A designated instrument flight rule
(IFR) arrival route linking a significant point, normally on an ATS route, with a point from which a
published instrument approach procedure can be commenced.
STANDARD INSTRUMENT DEPARTURE (SID) (ICAO) — A designated instrument flight rule
(IFR) departure route linking the aerodrome or a specified runway of the aerodrome with a speci-
fied point, normally on a designated ATS route, at which the enroute phase of a flight commen-
ces.
STANDARD INSTRUMENT DEPARTURE (SID) (USA) — A preplanned instrument flight rule
(IFR) air traffic control departure procedure printed for pilot use in graphic and/or textual form.
SIDs provide transition from the terminal to the appropriate enroute structure.
STANDARD ISOBARIC SURFACE — An isobaric surface used on a world-wide basis for repre-
senting and analyzing the conditions in the atmosphere.
STANDARD TERMINAL ARRIVAL ROUTE (STAR) (USA) — A preplanned instrument flight rule
(IFR) air traffic control arrival procedure published for pilot use in graphic and/or textual form.
STARs provide transition from the enroute structure to an outer fix or an instrument approach fix/
arrival waypoint in the terminal area.
STATION DECLINATION — The orientation with respect to true north of VHF transmitted signals.
The orientation is originally made to agree with the magnetic variation (an uncontrollable global
phenomenon) at the site. Hence station declination (fixed by man) may differ from changed mag-
netic variation until the station is reoriented.
STOPWAY — A defined rectangular area on the ground at the end of take-off run available pre-
pared as a suitable area in which an aircraft can be stopped in the case of an abandoned take-off.
SUBSTITUTE ROUTE — A route assigned to pilots when any part of an airway or route is unusa-
ble because of navaid status.
SUNSET AND SUNRISE — The mean solar times of sunset and sunrise as published in the
Nautical Almanac, converted to local standard time for the locality concerned. Within Alaska, the
end of evening civil twilight and the beginning of morning civil twilight, as defined for each locality.
SURFACE MOVEMENT GUIDANCE AND CONTROL SYSTEM (SMGCS) (USA) — Provisions
for guidance and control or regulation for facilities, information, and advice necessary for pilots of
aircraft and drivers of ground vehicles to find their way on the airport during low visibility opera-
tions and to keep the aircraft or vehicles on the surfaces or within the areas intended for their use.
Low visibility operations for this system means reported conditions of RVR 1200 or less.
SURVEILLANCE APPROACH (ASR) — An instrument approach wherein the air traffic controller
issues instructions, for pilot compliance, based on aircraft position in relation to the final approach
course (azimuth), and the distance (range) from the end of the runway as displayed on the con-
troller’s radar scope. The controller will provide recommended altitudes on final approach if
requested by the pilot.

DEFINITIONS AND ABBREVIATIONS

107

GLOSSARY

SURVEILLANCE RADAR — Radar equipment used to determine the position of an aircraft in
range and azimuth.
TAKE-OFF DISTANCE AVAILABLE (TODA) (ICAO) — The length of the take-off run available
plus the length of the clearway, if provided.
TAKE-OFF RUN AVAILABLE (TORA) (ICAO) — The length of runway declared available and
suitable for the ground run of an airplane taking off.
TAXIING — Movement of an aircraft on the surface of an aerodrome under its own power,
excluding take-off and landing.
TAXIWAY — A defined path on a land aerodrome established for the taxiing of aircraft and inten-
ded to provide a link between one part of the aerodrome and another, including:

Aircraft Stand Taxilane — A portion of an apron designated as a taxiway and intended to pro-
vide access to aircraft stands only.
Apron Taxiway — A portion of a taxiway system located on an apron and intended to provide
a through taxi route across the apron.
Rapid Exit Taxiway — A taxiway connected to a runway at an acute angle and designed to
allow landing aeroplanes to turn off at higher speeds than are achieved on other exit taxi-ways
and thereby minimizing runway occupancy times.

TERMINAL CONTROL AREA (ICAO) — A control area normally established at the confluence of
ATS routes in the vicinity of one or more major aerodromes.
TERMINAL ARRIVAL AREA (FAA) / TERMINAL AREA ALTITUDE (TAA) (ICAO) — Provides a
seamless and efficient transition from the enroute structure to the terminal environment to an
underlying RNAV instrument approach procedure for FMS and/or GPS equipped aircraft. Mini-
mum altitudes depict standard obstacle clearances compatible with the associated instrument
approach procedure. TAAs will not be found on all RNAV procedures, particularly in areas with a
heavy concentration of air traffic. When the TAA is published, it replaces the MSA for that
approach procedure. A standard racetrack holding pattern may be provided at the center IAF, and
if present may be necessary for course reversal and for altitude adjustment for entry into the pro-
cedure. In the latter case, the pattern provides an extended distance for the descent as required
by the procedure. The published procedure will be annotated to indicate when the course reversal
is not necessary when flying within a particular TAA (e.g., "NoPT"). Otherwise, the pilot is expec-
ted to execute the course reversal under the provisions of 14 CFR Section 91.175 (USA). The
pilot may elect to use the course reversal pattern when it is not required by the procedure, but
must inform air traffic control and receive clearance to do so.
TERMINAL VFR RADAR SERVICE (USA) — A national program instituted to extend the terminal
radar services provided instrument flight rules (IFR) aircraft to visual flight rules (VFR) aircraft.
The program is divided into four types of service referred to as basic radar service, terminal radar
service area (TRSA) service, Class “B” service and Class “C” service.

a. Basic Radar Service — These services are provided for VFR aircraft by all commissioned

terminal radar facilities. Basic radar service includes safety alerts, traffic advisories, limited

DEFINITIONS AND ABBREVIATIONS

108

GLOSSARY

radar vectoring when requested by the pilot, and sequencing at locations where procedures
have been established for this purpose and/or when covered by a letter of agreement. The
purpose of this service is to adjust the flow of arriving IFR and VFR aircraft into the traffic
pattern in a safe and orderly manner and to provide traffic advisories to departing VFR air-
craft.

b. TRSA Service — This service provides, in addition to basic radar service, sequencing of all

IFR and participating VFR aircraft to the primary airport and separation between all partici-
pating VFR aircraft. The purpose of this service is to provide separation between all partici-
pating VFR aircraft and all IFR aircraft operating within the area defined as a TRSA.

c. Class “B” Service — This service provides, in addition to basic radar service, approved sepa-

ration of aircraft based on IFR, VFR, and/or weight, and sequencing of VFR arrivals to the
primary airport(s).

d. Class “C” Service — This service provides, in addition to basic radar service, approved sepa-

ration between IFR and VFR aircraft, and sequencing of VFR aircraft, and sequencing of
VFR arrivals to the primary airport.

TERMINAL RADAR SERVICE AREA (TRSA) (USA) — Airspace surrounding designated air-
ports wherein ATC provides radar vectoring, sequencing and separation on a full-time basis for all
IFR and participating VFR aircraft. Service provided in a TRSA is called Stage III Service. Pilots’
participation is urged but is not mandatory.
THRESHOLD (THR) — The beginning of that portion of the runway usable for landing.
THRESHOLD CROSSING HEIGHT (TCH) — The theoretical height above the runway threshold
at which the aircraft's glide slope antenna (or equivalent position) would be if the aircraft maintains
the trajectory of the ILS glide slope, MLS glide path or charted descent angle.
TOTAL ESTIMATED ELAPSED TIME — For IFR flights, the estimated time required from take-
off to arrive over that designated point, defined by reference to navigation aids, from which it is
intended that an instrument approach procedure will be commenced, or, if no navigation aid is
associated with the destination aerodrome, to arrive over the destination aerodrome. For VFR
flights, the estimated time required from take-off to arrive over the destination aerodrome.
TOUCHDOWN — The point where the nominal glide path intercepts the runway.
NOTE: “Touchdown” as defined above is only a datum and is not necessarily the actual point at
which the aircraft will touch the runway.
TOUCHDOWN ZONE ELEVATION (TDZE) — The highest elevation in the first 3000ft of the
landing surface.
TRACK — The projection on the earth’s surface of the path of an aircraft, the direction of which
path at any point is usually expressed in degrees from North (true, magnetic or grid).
TRAFFIC ALERT AND COLLISION AVOIDANCE SYSTEM (TCAS) — An airborne collision
avoidance system based on radar beacon signals which operates independent of ground-based
equipment.
TCAS-I generates traffic advisory only;

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GLOSSARY

TCAS-II generates traffic advisories, and resolution (collision avoidance) advisories in the vertical
plane.
TRAFFIC AVOIDANCE ADVICE — Advice provided by an air traffic services unit specifying
manoeuvres to assist a pilot to avoid a collision.
TRAFFIC INFORMATION — Information issued by an air traffic services unit to alert a pilot to
other known or observed air traffic which may be in proximity to the position or intended route of
flight and to help the pilot avoid a collision.
TRANSITION ALTITUDE (TA) — The altitude in the vicinity of an airport at or below which the
vertical position of an aircraft is controlled by reference to altitudes (MSL).
TRANSITION HEIGHT — The height in the vicinity of an airport at or below which the vertical
position of an aircraft is expressed in height above the airport reference datum.
TRANSITION LAYER — The airspace between the transition altitude and the transition level. Air-
craft descending through the transition layer will use altimeters set to local station pressure, while
departing aircraft climbing through the layer will be using standard altimeter setting (QNE) of
29.92 inches of Mercury, 1013.2 millibars, or 1013.2 hectopascals.
TRANSITION LEVEL (TL) — The lowest flight level available for use above the transition altitude.
TROPICAL CYCLONE — Generic term for a non-frontal synoptic-scale cyclone originating over
tropical or sub-tropical waters with organized convection and definite cyclonic surface wind circu-
lation.
TROPICAL CYCLONE ADVISORY CENTRE (TCAC) — A meteorological centre designated by
regional air navigation agreement to provide advisory information to meteorological watch offices,
world area forecast centres and international OPMET databanks regarding the position, forecast
direction and speed of movement, central pressure and maximum surface wind of tropical cyclo-
nes.
TURN ANTICIPATION — Turning maneuver initiated prior to reaching the actual airspace fix or
turn point that is intended to keep the aircraft within established airway or route boundaries.
UNCERTAINTY PHASE — A situation wherein uncertainty exists as to the safety of an aircraft
and its occupants.
UNMANNED FREE BALLOON — A non-powerdriven, unmanned, lighter-than-air aircraft in free
flight.
NOTE: Unmanned free balloons are classified as heavy, medium or light in accordance with spec-
ifications contained in ICAO Rules of the Air, Annex 2, Appendix 4.
UPPER-AIR CHART — A meteorological chart relating to a specified upper-air surface or layer of
the atmosphere.
URGENCY — A condition concerning the safety of an aircraft or other vehicle, or of some person
on board or within sight, but which does not require immediate assistance.
VECTORING — Provision of navigational guidance to aircraft in the form of specific headings,
based on the use of an ATS surveillance system.

DEFINITIONS AND ABBREVIATIONS

110

GLOSSARY

VERTICAL NAVIGATION (VNAV) — That function of RNAV equipment which provides guidance
in the vertical plane.
VERTICAL PATH ANGLE (VPA) (ICAO) — Angle of the published final approach descent in
Baro-VNAV procedures.
VERTICAL PATH ANGLE (VPA) (USA) — The descent angle shown on some non-precision
approaches describing the geometric descent path from the Final approach fix (FAF), or on occa-
sion from an intervening stepdown fix, to the Threshold Crossing Height (TCH). This angle may or
may not coincide with the angle projected by a Visual Glide Slope Indicator (VASI, PAPI, PLASI,
etc.)
VERY HIGH FREQUENCY (VHF) — The frequencies between 30MHz and 300MHz (200MHz –
3GHz is considered as UHF in the Aviation).
VFR FLIGHT — A flight conducted in accordance with the visual flight rules.
VIBAL — (Visibilité Balise) Is the method whereby a human observer (or pilot in take-off position)
determines the RVR by counting specific markers adjacent to the runway or by counting runway
edge lights.
VISIBILITY (ICAO) — 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.

a. Flight Visibility — The visibility forward from the cockpit of an aircraft in flight.
b. Ground Visibility — The visibility at an aerodrome as reported by an accredited observer.

c. Runway Visual Range (RVR) — The range over which the pilot of an aircraft on the center-

line of a runway can see the runway surface markings or the lights delineating the runway or
identifying its centerline.

VISIBILITY (USA) — 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. Visibility is reported as statute or nautical miles, hundreds of feet or meters.

a. Flight Visibility — The average forward horizontal distance, from the cockpit of an aircraft in

flight, at which prominent unlighted objects may be seen and identified by day and prominent
lighted objects may be seen and identified by night.

b. Ground Visibility — Prevailing horizontal visibility near the earth’s surface as reported by the

United States National Weather Service or an accredited observer.

c. Prevailing Visibility — The greatest horizontal visibility equaled or exceeded throughout at

least half the horizon circle which need not necessarily be continuous.

d. Runway Visibility Value (RVV) — The visibility determined for a particular runway by a trans-

missometer. A meter provides a continuous indication of the visibility (reported in miles or
fractions of miles) for the runway. RVV is used in lieu of prevailing visibility in determining
minimums for a particular runway.

DEFINITIONS AND ABBREVIATIONS

111

GLOSSARY

e. Runway Visual Range (RVR) — An instrumentally derived value, based on standard calibra-

tions, that represents the horizontal distance a pilot will see down the runway from the
approach end; it is based on the sighting of either high intensity runway lights or on the
visual contrast of other targets whichever yields the greater visual range. RVR, in contrast to
prevailing or runway visibility, is based on what a pilot in a moving aircraft should see looking
down the runway. RVR is horizontal visual range, not slant visual range. It is based on the
measurement of a transmissometer made near the touchdown point of the instrument
runway and is reported in hundreds of feet. RVR is used in lieu of RVV and/or prevailing visi-
bility in determining minimums for a particular runway.

1. Touchdown RVR — The RVR visibility readout values obtained from RVR equipment

serving the runway touchdown zone.

2. Mid-RVR — The RVR readout values obtained from RVR equipment located midfield of

the runway.

3. Rollout RVR — The RVR readout values obtained from RVR equipment located nearest

the rollout end of the runway.

VISUAL APPROACH (ICAO) — An approach by an IFR flight when either part or all of an instru-
ment approach procedure is not completed and the approach is executed in visual reference to
terrain.
VISUAL APPROACH (USA) — An approach conducted on an instrument flight rules (IFR) flight
plan which authorizes the pilot to proceed visually and clear of clouds to the airport. The pilot
must, at all times, have either the airport or the preceding aircraft in sight. This approach must be
authorized and under the control of the appropriate air traffic control facility. Reported weather at
the airport must be ceiling at or above 1000ft and visibility of 3 miles or greater.
VISUAL DESCENT POINT (VDP) — A defined point on the final approach course of a non-preci-
sion straight-in approach procedure from which normal descent from the MDA to the runway
touchdown point may be commenced, provided the approach threshold of that runway, or
approach lights, or other markings identifiable with the approach end of that runway are clearly
visible to the pilot.
VISUAL MANOEUVRING (CIRCLING) AREA — The area in which obstacle clearance should be
taken into consideration for aircraft carrying out a circling approach.
VISUAL METEOROLOGICAL CONDITIONS (VMC) — Meteorological conditions expressed in
terms of visibility, distance from cloud, and ceiling equal to or better than specified minima.
NOTE: The specified minima are contained in ICAO Rules of the Air, Annex 2, Chapter 4.
VOLMET BROADCAST — Routine broadcast of meteorological information for aircraft in flight.
VOLCANIC ASH ADVISORY CENTRE (VAAC) — A meteorological centre designated by
regional air navigation agreement to provide advisory information to meteorological watch offices,
area control centres, flight information centres, world area forecast centres, relevant regional area
forecast centres and international OPMET data banks regarding the lateral and vertical extent and
forecast movement of volcanic ash in the atmosphere following volcanic eruptions.

DEFINITIONS AND ABBREVIATIONS

112

GLOSSARY

VOLMET BROADCAST — Provision of current aerodrome meteorological reports (METAR) and
special meteorological reports (SPECI), aerodrome forecasts (TAF), SIGMET by means of contin-
uous and repetitive voice broadcasts for aircraft in flight.
VOLMET DATA LINK SERVICE (D-VOLMET) — Provision of current METAR, SPECI, TAF,
SIGMET, special air-reports not covered by SIGMET and, where available, AIRMET via data link.
WARNING AREA (USA) — [see SPECIAL USE AIRSPACE (SUA)].
WAYPOINT — A specified geographical location used to define an area navigation route or the
flight path of an aircraft employing area navigation. Waypoints are identified as either:

Fly-by waypoint — A fly-by waypoint requires the use of turn anticipation to avoid overshoot of
the next flight segment; or
Fly-over waypoint — A fly-over waypoint precludes any turn until the waypoint is overflown
and is followed by an intercept maneuver of the next flight segment.

WEATHER SYSTEMS PROCESSOR (WSP) — An add-on weather processor to selected Airport
Surveillance Radar (ASR)-9 facilities that adds Doppler weather radar capability and provides
wind shear and microburst warnings. The system gives controllers timely and accurate warnings
for relaying to pilots via radio communications. The WSP also provides controllers with thunder-
storm cell locations and movement as well as the predicted future position and intensity of wind
shifts that may affect airport operations. The system can also process precipitation data to reduce
false severe weather reports caused by anomalous propagation.
WIDE AREA AUGMENTATION SYSTEM (WAAS) — WAAS is a navigation system developed
for civil aviation that provides extremely accurate horizontal and vertical navigation for all classes
of aircraft in all phases of flight - including enroute navigation, airport departures, and airport arriv-
als. This includes vertically-guided landing approaches in instrument meteorological conditions at
all qualified locations.
WORLD AREA FORECAST CENTRE (WAFC) — A meteorological centre designated to prepare
and issue significant weather forecasts and upper-air forecasts in digital and/or pictorial form on a
global basis direct States by appropriate means as part of the aeronautical fixed service.
WORLD AREA FORECAST SYSTEM (WAFS) — A world-wide system by which world area fore-
cast centres provide aeronautical meteorological en-route forecasts in uniform standardized for-
mats.

DEFINITIONS AND ABBREVIATIONS

113

GLOSSARY

DEFINITIONS

A/A

Air to Air

AAF

Army Air Field

AAIM

Aircraft Autonomous Integrity Monitoring

AAIS

Automated Aerodrome Information Service

AAL

Above Aerodrome Level

AAS

Airport Advisory Service

AAU

Authorized Approach UNICOM

Air Base

ABM

Abeam

ABN

Aerodrome Beacon

Air Carrier

ACA

Arctic Control Area

ACA

Approach Control Area

ACAS

Airborne Collision Avoidance System

ACARS

Airborne Communications Addressing and Reporting System

ACC

Area Control Center

ACFT

Aircraft

ACN

Aircraft Classification Number

Aerodrome

ADA

Advisory Area

ADF

Automatic Direction Finding

ADIZ

Air Defense Identification Zone

ADNL

Additional

ADR

Advisory Route

ADS

Automatic Dependent Surveillance

ADS-B

Automatic Dependent Surveillance-Broadcast

ADV

Advisory Area

AEIS

Aeronautical Enroute Information Service

AER

Approach End of Runway

AERADIO

Air Radio

DEFINITIONS AND ABBREVIATIONS

114

ABBREVIATIONS USED IN AIRWAY MANUAL

AERO

Aerodrome

AF Aux

Air Force Auxiliary Field

AFB

Air Force Base

AFIS

Aerodrome Flight Information Service

AFIS

Automatic Flight Information Services (FAA)

AFLD

Airfield

AFN

American Forces Network

AFRS

Armed Forces Radio Stations

AFRU

Aerodrome Frequency Response Unit

AFS

Air Force Station

AFSS

Automated Flight Service Station

A/G

Air-to-Ground

AGL

Above Ground Level

AGNIS

Azimuth Guidance Nose-in-Stand

Alert Height

AHP

Army Heliport

AIRAC

Aeronautical Information Regulation and Control

AIREP

Air-Report

AIS

Aeronautical Information Services

ALA

Aircraft Landing Area

ALF

Auxiliary Landing Field

ALS

Approach Light System

ALS

Low Intensity Approach Lights

ALT

Altitude

ALTN

Alternate

AMA

Area Minimum Altitude

AMSL

Above Mean Sea Level

ANGB

Air National Guard Base

AOC

Aircraft Operator Certificate

AOE

Airport/Aerodrome of Entry

AOM

Airport Operating Minimums

DEFINITIONS AND ABBREVIATIONS

115

ABBREVIATIONS USED IN AIRWAY MANUAL

AOR

Area of Responsibility

APAPI

Abbreviated Precision Approach Path Indicator

APC

Area Positive Control

APCH

Approach

APP

Approach Control

APT

Airport

APV

Approach Procedure with Vertical Guidance

Authorization Required

ARB

Air Reserve Base

ARINC

Aeronautical Radio, Inc.

ARO

Aerodrome Reporting Officer

ARP

Airport Reference Point

ARR

Arrival

ARTCC

Air Route Traffic Control Center

ASDA

Accelerate Stop Distance Available

ASDE-X

Airport Surface Detection Equipment - Model X

ASMGCS

Advanced Surface Movement Guidance and Control System

ASOS

Automated Surface Observing System

ASR

Airport Surveillance Radar

ASSC

Airport Surface Surveillance Capability

ATA

Actual Time of Arrival

ATCAA

Air Traffic Control Assigned Airspace

ATCC

Air Traffic Control Center

ATCT

Air Traffic Control Tower

ATD

Actual Time of Departure

ATF

Aerodrome Traffic Frequency

ATFM

Air Traffic Flow Management

ATIS

Automatic Terminal Information Service

ATND SKD

Attended Scheduled Hours

ATS

Air Traffic Service

ATZ

Aerodrome Traffic Zone

DEFINITIONS AND ABBREVIATIONS

116

ABBREVIATIONS USED IN AIRWAY MANUAL

Approach UNICOM

AUP

Airspace Utilization Plane

AUTH

Authorized

AUW

All-Up Weight

AUX

Auxiliary

AVBL

Available

AWIB

Aerodrome Weather Information Broadcast

AWIS

Aerodrome Weather Information Service

AWOS

Automated Weather Observing System

AWSS

Aviation Weather Sensor System

AWY

Airway

AZM

Azimuth

Baro VNAV

Barometric Vertical Navigation

Back Course

BCM

Back Course Marker

BCN

Beacon

BCOB

Broken Clouds or Better

BCST

Broadcast

BDRY

Boundary

BLDG

Building

Back Marker

BRG

Bearing

B-RNAV

Basic RNAV

Broadcast Station (Commercial)

ATC IFR Flight Plan Clearance Delivery Frequency

Converted Met Visibility

CADIZ

Canadian Air Defense Identification Zone

CAE

Control Area Extension

CA/GRS

Certified Air/Ground Radio Service

CANPA

Constant Angle Non-Precision Approach

CARS

Community Aerodrome Radio Station

DEFINITIONS AND ABBREVIATIONS

117

ABBREVIATIONS USED IN AIRWAY MANUAL

CAT

JEPPESEN GENERAL AIRWAY MANUAL (Issue Date 1 JUL 21) - page 4