1. Home
2. Organization
3. Organizational Chart
4. Safety & Security Group
5. Civil Aviation
6. Civil Aviation Secretariat
7. Aviation Terminology and Linguistic Services
8. Glossary for Pilots and Air Traffic Services Personnel (TP 11958E)
9. D

D

DA

Abbreviation for: decision altitude

Fr: DA

danger area

An airspace of defined dimensions above international waters within which activities dangerous to the flight of non-participating aircraft could take place at specified times.

Fr: zone dangereuse

dangerous goods

Articles or substances that could pose a significant risk to health, safety, property or the environment.

Fr: marchandises dangereuses

data link ATIS

An automatic terminal information service (ATIS) provided by data link.

Fr: ATIS par liaison de données

data link initiation capability

Fr: capacité d’amorçage de la liaison de données

data link VOLMET

In-flight meteorological information provided by data link.

Fr: VOLMET par liaison de données

date-time group

A combination of the date and time in a single six-figure group. When used in the text of a NOTAM, it is composed of ten figures, e.g. 9501191200. The first two digits indicate the year; the second two, the month; the third two, the day; and the last four, the hour and the minutes.

Fr: groupe date-heure

D-ATIS

Abbreviation for: data link ATIS

Fr: D-ATIS

day

Canada (CARs): Other expression for: daylight

daylight

The period of time during any day that begins with the morning civil twilight and ends with the evening civil twilight.

Fr: lumière du jour

DCPC

Abbreviation for: direct controller-pilot communications

Fr: DCPC

dead reckoning navigation

The estimating or determining of position by advancing an earlier known position by the application of direction, time and speed data.

Fr: navigation à l’estime

decision altitude

A specified altitude in the precision approach or approach with vertical guidance at which a missed approach must be initiated if the required visual reference to continue the approach to land has not been established.

Fr: altitude de décision

decision height

A specified height in the precision approach or approach with vertical guidance at which a missed approach must be initiated if the required visual reference to continue the approach to land has not been established.

Fr: hauteur de décision

defence visual flight rules

Rules applicable to flights within an air defence identification zone (ADIZ) conducted under VFR.

Fr: règles de vol à vue de la défense

Department of National Defence

Canada: The federal authority responsible for military aviation.

Fr: ministère de la Défense nationale

departure control

A function of an approach control facility providing ATC service for departing IFR and, under certain conditions, VFR aircraft.

Fr: contrôle des départs

departure controller

A duty controller assigned to a departure control position.

Fr: contrôleur des départs

departure time

The time an aircraft becomes airborne.

Fr: heure de départ

designated unit

A unit that serves as a communications link into the NAV CANADA system for the dissemination of information and that monitors or supports the day-to-day operation of a community aerodrome radio station (CARS). The designated unit may have one or more CARS reporting to it.

Fr: unité désignée

destination alternate aerodrome

An alternate aerodrome specified in the flight plan (FP) to which an aircraft may proceed should it become either impossible or inadvisable to land at the aerodrome of intended landing.

Fr: aérodrome de dégagement à destination

destination unit

The unit whose area of responsibility (AOR) encompasses the destination aerodrome.

Fr: unité de destination

DETRESFA

ICAO: Abbreviation for: distress phase

Fr: DETRESFA

deviation

(1) A departure from a current clearance, such as an off-course manoeuvre, to avoid weather or turbulence.

Fr: déviation

(2) The angular difference between magnetic and compass headings.

Fr: déviation

DF

Abbreviation for: direction finder

Fr: DF

DF approach procedure

U.S.: A procedure used under emergency conditions where another instrument approach procedure (IAP) cannot be executed. DF guidance for an instrument approach is given by ATC facilities with DF capability.

DF fix

The geographical location of an aircraft obtained by one or more DF.

Fr: repère radiogoniométrique

DF guidance

Headings provided to aircraft by facilities equipped with direction-finding equipment. These headings, if followed, will lead the aircraft to a predetermined point, such as the radio direction-finding station or an airport. DF guidance is given to aircraft in distress or to other aircraft that request the service.

Fr: guidage radiogoniométrique

DF station

Other expression for: radio direction-finding station

DF steer

Other expression for: DF guidance

DH

Abbreviation for: decision height

Fr: DH

direct

A straight-line flight between two NAVAIDs, fixes, points, or any combination thereof. When used by pilots in describing off-airway routes, points defining direct route segments become compulsory reporting points unless the aircraft is under radar contact.

Fr: vol direct

directed bright light

A lighting system, other than laser light, designed to project a bright light into space.

Fr: lumière dirigée à haute intensité

direct flight

Other expression for: direct

direction finder

Receiving equipment, complete with antennas and associated circuits, used for direction finding.

Fr: radiogoniomètre

direction-finding station

Other expression for: radio direction-finding station

direct controller-pilot communications

Communications between a controller and a pilot without resort to a relay through another unit.

Fr: communications directes contrôleur-pilote

Direct User Access Terminal System

A computer-based system provided by a vendor to pilots or other operational personnel. DUATS supplies the aviation weather and NOTAM information necessary for pre-flight planning via computer terminals or personal computers owned by the vendor or users.

Fr: terminal à accès direct pour les usagers

discrete code

Other expression for: discrete SSR code

discrete frequency

A separate radio frequency for use in direct communications that reduces frequency congestion by controlling the number of users on a particular frequency at one time.

Fr: fréquence discrète

discrete SSR code

A specific mode 3/A code assigned to one aircraft only.

Fr: code SSR discret

displaced threshold

A threshold not located at the end of a runway.

Fr: seuil décalé

“Disregard”

An expression used in radiocommunication meaning “Ignore or consider that transmission as not sent.”

Fr: « Ignorez »

distance measuring equipment

Airborne and ground equipment used to measure the slant range distance from a DME NAVAID in nautical miles.

Fr: équipement de mesure de distance

distance of turn anticipation

The distance measured parallel to the course from the earliest position of the intermediate approach waypoint (IWP) at which the turn will be commenced.

Fr: distance d’anticipation de virage

distress

Condition of being threatened by serious and/or imminent danger and of requiring immediate assistance. The spoken word for distress is MAYDAY, and it is pronounced three times.

Fr: détresse

distress phase

(1) A phase that begins when

(a) the fuel on board is considered to be exhausted or to be insufficient to enable the aircraft to land safely;

(b) information is received that indicates that the operating efficiency of the aircraft has been impaired to the extent that a forced landing is likely; or

(c) information is received that the aircraft is about to make, or has made, a forced landing.

Fr: phase de détresse

(2) ICAO: A situation wherein there is reasonable certainty that an aircraft and its occupants are threatened by grave and imminent danger or require immediate assistance.

Fr: phase de détresse

dive brake

Other expression for: speed brake

DLIC

Abbreviation for: data link initiation capability

Fr: DLIC

DME

Abbreviation for: distance measuring equipment

Fr: DME

DME fix

A geographical position determined by reference to a NAVAID, which provides distance and azimuth information, and defined by a specified distance in nautical miles and a radial in degrees magnetic, true or grid from the NAVAID.

Fr: repère DME

DME separation

The spacing of aircraft in terms of distances (nautical miles) determined by reference to DME.

Fr: espacement DME

DND

Canada: Abbreviation for: Department of National Defence

Fr: MDN

DOD FLIP

U.S.: Department of Defense Flight Information Publications used for flight planning, en route, and terminal operations.

downwind

Other expression for: downwind leg

downwind leg

A flight path parallel to the landing runway (or landing path) in the direction opposite to landing. The downwind leg normally extends between the crosswind leg and the base leg.

Fr: étape vent arrière

downwind termination waypoint

The waypoint located downwind to the landing runway abeam the final approach course fix (FACF) where an open RNAV STAR terminates.

Fr: point de cheminement terminal vent arrière

DR

Abbreviation for: dead reckoning navigation

Fr: DR

drag chute

A parachute device installed on certain aircraft that is deployed to assist in deceleration of the aircraft.

Fr: parachute de freinage

drifting snow

Snow that is raised less than approximately 7 ft above ground.

Fr: chasse-neige basse

DTA

Abbreviation for: distance of turn anticipation

Fr: DTA

DTW

Abbreviation for: downwind termination waypoint

Fr: DTW

DUATS

Abbreviation for: Direct User Access Terminal System

Fr: DUATS

DVFR

Abbreviation for: defence visual flight rules

Fr: DVFR

D-VOLMET

Abbreviation for: data link VOLMET

Fr: D-VOLMET

Date modified:

2012-03-14

Primary navigation