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Aviation Terminology I

You must start using the language of aviation if you hope to be successful at writing Transport Canada examinations and conversing with other pilots. Here is a start on the terminology. Don't try to absorb it all at once. Go over it quickly and as the course progresses, check back to this section to see what you have absorbed and what remains to be worked on.

Glossary of Aeronautical Terms

“Acknowledge”
“Let me know that you have received and understood my message.”

Active Runway
Any runway or runways currently being used for takeoff or landing. When multiple runways are used, they are all considered active runways. When an aircraft is landing or taking off on an airport surface other than a runway, the direction of flight will determine the active runway.

Aerodrome
Any area of land, water (including the frozen surface thereof) or other supporting surface used or designed, prepared, equipped or set apart for use either in whole or in part of the arrival and departure, movement or servicing of aircraft and includes any buildings, installations and equipment in connection therewith.

Air Defence Identification Zone (ADIZ)
Airspace of defined dimensions extending upwards from the surface of the earth within which certain rules for the security control of air traffic apply.

Airport
An aerodrome in respect of which a Canadian Aviation document is in force.

Airport Traffic
All traffic on the manoeuvring area of an airport and all aircraft flying in the vicinity of an airport.

Air Traffic
All aircraft in flight and aircraft operating on the manoeuvring area of an aerodrome.

Air Traffic Control Clearance
Authorization by an air traffic control unit for an aircraft to proceed within controlled airspace under specified conditions.

Air Traffic Control Instruction
A directive issued by an air traffic control unit for air traffic control purposes.

Air Traffic Control Service
Services, other than flight information services, provided for the purpose of, preventing collisions between aircraft, aircraft and obstructions, and aircraft and vehicles on the manoeuvring area; and expediting and maintaining an orderly flow of air traffic.

Air Traffic Control Unit
An area control centre established to provide air traffic control service to Instrument Flight Rules (IFR) flights and Controlled Visual Flight Rules (CVFR) flights; a terminal control unit established to provide air traffic control service to IFR flights and controlled VFR flights operating within a terminal control area; or an airport control tower unit established to provide air traffic control service to airport traffic; as the circumstances require.

Apron
That part of an aerodrome, other than the manoeuvring area, intended to accommodate the loading and unloading of passengers and cargo; the refuelling, servicing, maintenance and parking of aircraft; and any movement of aircraft, vehicles and pedestrians necessary for such purposes.

Arctic Control Area
Controlled airspace within the Northern Domestic Airspace as defined in the Designated Airspace Handbook (TP 1820E).

Area Minimum Altitude (AMA)
The lowest altitude to be used under Instrument Meteorological Conditions (IMC) that will provide a minimum vertical clearance of 1 000 feet or in designated mountainous terrain 2 000 feet above all obstacles located in the area specified, rounded up to the nearest 100 foot increment.

Canadian Domestic Airspace (CDA)
All navigable airspace of Canada designated and defined as such in the Designated Airspace Handbook (TP 1820E).

Ceiling
The lowest height at which a broken or overcast condition exists, or the vertical visibility when an obscured condition such as snow, smoke or fog exists, whichever is the lower.

Control Area Extension (CAE)
Controlled airspace of defined dimensions within the Low Level Airspace extending upwards from 2 200 feet above the surface of the earth unless otherwise specified.

Controlled Airspace
Airspace of defined dimensions within which air traffic control service is provided.

Controlled VFR Flight (CVFR)
A flight conducted under VFR within Class B airspace and in accordance with an air traffic control clearance.

Control Zone (CZ)
Controlled airspace of defined dimensions extending upwards from the surface of the earth up to and including 3 000 feet AAE unless otherwise specified.

Cruising Altitude
An altitude, as shown by a constant altimeter indication in relation to a fixed and defined datum, maintained during a flight or portion thereof.

Daylight
In respect of any place in Canada, the period of time in any day when the centre of the sun’s disc is less than 6° below the horizon, and in any place where the sun rises and sets daily, may be considered to be the period of time commencing / hour before sunrise and ending / hour after sunset.

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

“Expedite”
A term used by ATC when prompt compliance by the pilot is required to avoid the development of an imminent situation.

Final Approach
That segment of an instrument approach between the final approach fix or point and the runway, airport or missed approach point, whichever is encountered last, wherein alignment and descent for landing are accomplished.

Flight Information Region (FIR)
Airspace of defined dimensions extending upwards from the surface of the earth within which flight information service and alerting service are provided.

Flight Level (FL)
An altitude expressed in hundreds of feet indicated on an altimeter set to 29.92 inches of mercury or 1013.2 millibars.

Flight Service Station (FSS)
An aeronautical facility providing mobile and fixed communications, flight information, search and rescue alerting, and weather services to pilots and other users.

Flight Visibility
The average range of visibility at any given time forward from the cockpit of an aircraft in flight.

Go Around
An ATC instruction for a pilot to abandon an approach or landing. Unless otherwise advised by ATC, a VFR aircraft or an aircraft conducting a visual approach should overfly the runway while climbing to traffic pattern altitude and enter the traffic pattern via the crosswind leg. A pilot conducting an instrument approach should execute the published missed approach procedure or proceed as instructed by ATC.

Ground Visibility

The visibility at an aerodrome as contained in a weather observation reported by an Air Traffic Control (ATC) unit; a Flight Service Station (FSS); a Community Aerodrome Radio Station (CARS); a radio station that is ground-based and operated by an air carrier; or an Automated Weather Observation System (AWOS).

“Have Numbers”
Expression used by pilots to indicate that they have received runway, wind and altimeter information only.

Heading
The direction in which the longitudinal axis of an aircraft is pointed, usually expressed in degrees from North (True, Magnetic, Compass or Grid).

Heavy Aircraft / Jet
For wake turbulence categorization purposes, an aircraft certificated for a maximum takeoff weight of 136 000 kilograms (300 000 lbs) or more.

Height Above Aerodrome (HAA)
The height in feet of the Minimum Descent Altitude (MDA) above the published aerodrome elevation. The Height Above Aerodrome (HAA) will be published for all circling minima.

High Level Air Route
In the High Level Airspace, a prescribed track between specified radio aids to navigation.

High Level Airspace
All airspace within the Canadian Domestic Airspace 18 000 feet ASL and above.

High Level Airway
In controlled High Level Airspace, a prescribed track between specified radio aids to navigation.

Instrument Meteorological Conditions (IMC)
Meteorological conditions less than the minima specified in Division VI of Subpart of CARs, Part VI, for visual meteorological conditions, expressed in terms of visibility and distance from cloud.

Intersection
(a) A point on the surface of the earth over which two or more position lines intersect. The position lines may be true bearings from NDBs (magnetic bearings shown on chart for pilot usage), radials from VHF/UHF aids, centre lines of airways, fixed RNAV routes, air routes, localizers and DME distances.
(b) The point where two runways, a runway and a taxiway, or two taxiways cross or meet. Land and Hold Short Operations (LAHSO) Operations which include simultaneous takeoffs and landings and/or simultaneous landings when a landing aircraft is able and is instructed by the controller to hold-short of the intersecting runway/taxiway or designated hold-short point.

Launch Weight
The total weight of a hang glider or an ultra-light aeroplane when it is ready for flight including any equipment, instruments and the maximum quantity of fuel and oil that it is designed to carry, but does not include:
(a) the weight of any float equipment to a maximum weight of 34 kg;
(b) the weight of the occupant; or
(c) the weight of any ballistic parachute installation.

Low Approach
An approach over an airport or runway following an instrument or VFR approach, including the go-around manoeuvre, where the pilot intentionally does not intend to land.

Low Level Air Route
Within low level airspace, a route extending upwards from the surface of the earth and for which air traffic control is not provided.

Low Level Airspace
All airspace within the Canadian Domestic Airspace below 18 000 feet ASL.

Low Level Airway
Within low level airspace, a route extending upwards from 2 200 feet above the surface of the earth up to, but not including, 18 000 feet ASL, and for which air traffic control is provided.

Manoeuvring Area
That part of an aerodrome intended to be used for the taking off and landing of aircraft and for the movement of aircraft associated with takeoff and landing, excluding aprons.

MEDEVAC
A term used to request ATS priority handling for a medical evacuation flight based on a medical emergency in the transport of patients, organ donors, organs, or other urgently needed life-saving medical material. The term is to be used on flight plans and in radiotelephony communications if a pilot determines that a priority is required.

Military Operations Area (MOA)
Airspace of defined dimensions established to segregate certain military activities from IFR traffic and to identify for VFR traffic where these activities are conducted.

Military Terminal Control Area (MTCA)
Controlled airspace of defined dimensions designated to serve arriving, departing and enroute aircraft, and within which special procedures and exemptions exist for military aircraft.

Minimum Obstruction Clearance Altitude (MOCA)
The altitude above sea level in effect between radio fixes on low level airways or air routes which meet the IFR obstruction clearance requirement for the route segment.

Minimum Reception Altitude (MRA)
Minimum reception altitude, when applied to a specific VHF/ UHF intersection, is the lowest altitude above sea level at which acceptable navigational signal coverage is received to determine the intersection.

Minimum Sector Altitude (MSA)
The lowest altitude which will provide a minimum clearance of 1 000 ft above all objects located in an area contained within a sector of a circle of 25 NM radius centred on a radio aid to navigation.

Missed Approach (MA)
A manoeuvre conducted by the pilot when an instrument approach cannot be completed to a landing. Also, used by the pilot to indicate that a missed approach is being executed.

Missed Approach Point (MAP)
A point prescribed in each instrument approach procedure at which a missed approach shall be initiated if the required visual reference is not acquired.

Mountainous Region
An area of defined lateral dimensions above which special rules concerning minimum enroute altitudes apply.

Movement Area
That part of an aerodrome intended to be used for the surface movement of aircraft, and includes the manoeuvring area and aprons.

Navigation Aid (NAVAID)
Any visual or electronic device, airborne or on the surface of the earth which provides point-to-point guidance information or position data to aircraft in flight.

Night
In respect of any place in Canada, the period of time when the centre of the sun’s disc is more than 6° below the horizon, and in any place where the sun rises and sets daily, may be considered to be the period of time commencing / hour after sunset and ending / hour before sunrise. (For military pilots, the definition in CFP100 applies.)

North Warning System (NWS) (see COM 6.7.2)
A system that provides airspace surveillance and command and control capability for air defence identification over the northern approaches to the continent. It consists of 5 longrange radars (LRR) and 39 short-range radars (SRR) across the Canadian Arctic and Alaska. Systems deployed on Canadian territory are operated and maintained by Canada for NORAD on behalf of Canada and the United States.

NOTAM
A notice 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 operations.

Obstacle
An existing object, object of natural growth, or terrain at a fixed geographical location or which may be expected at a fixed location within a prescribed area with reference to which vertical clearance is or must be provided during flight operations.

Obstacle Rich Environment (ORE)
An environment is obstacle rich when it is not possible to construct an unguided discontinued approach using procedural method. Approach operations in an Obstacle Rich Environment require supplementary guidance to proceed along a published course to the missed approach point and to achieve a climb to a minimum IFR altitude. Approach procedures will be annotated “CAUTION: OBSTACLE RICH ENVIRONMENT”.

Pilot’s Discretion
When used in conjunction with altitude assignments, means that ATC has offered the pilot the option of starting climb or descent whenever the pilot wishes. Pilots may temporarily level off at any intermediate altitude; however, once an altitude has been vacated, the pilot may not return to that altitude because ATC may have reassigned it to another aircraft. Pilots are expected to advise ATC of any temporary level-off at any intermediate altitude.

Preferred Runway
When there is no active runway the preferred runway is considered to be the most suitable operational runway taking into account such factors as the runway most nearly aligned with the wind, noise abatement or other restrictions which prohibit the use of certain runway(s); ground traffic and runway conditions.

“Radar Identified”
Used by ATC to inform the pilot that the aircraft has been identified on the radar display and radar flight following will be provided until radar identification is terminated.

Radar Identification
The process of ascertaining that a particular target is the radar return from a specific aircraft.

Radial
A magnetic bearing from a VOR, TACAN, or VORTAC facility, except for facilities in the Northern Domestic Airspace which may be oriented on True or Grid North.

Required Visual Reference
In respect of an aircraft on an approach to a runway, means that section of the approach area of the runway or those visual aids that, when viewed by the pilot of the aircraft, enables the pilot to make an assessment of the aircraft position and the rate of change of position relative to the nominal flight path.

Restricted Area
Class F airspace of defined dimensions above the land areas or territorial waters within which the flight of aircraft is restricted in accordance with certain specified conditions.

Runway Heading
The Magnetic or True, as applicable, direction that corresponds with the runway centre line.

Runway Incursion
Any occurrence at an airport involving the unauthorized or unplanned presence of an aircraft, vehicle, or person on the protected area of a surface designated for aircraft landings and departures.

Southern Control Area (SCA) (see RAC Figure 2.3)
Controlled airspace within the Southern Domestic Airspace as defined in the Designated Airspace Handbook (TP 1820E).

Southern Domestic Airspace (SDA) (see RAC Figure 2.1)
All airspace within the Canadian Domestic Airspace as defined in the Designated Airspace Handbook (TP 1820E).

“Squawk Ident”
A request for a pilot to activate the aircraft transponder identification feature.

Stop-and-Go
A procedure in which an aircraft lands, makes a complete stop on the runway, and then commences a takeoff from that point.

Straight-In Approach – VFR
Entry into the traffic pattern by interception of the extended runway centre line (final approach course) without executing any other portion of the traffic pattern.

Terminal Control Area (TCA)
Controlled airspace of defined dimensions designated to serve arriving, departing and en-route aircraft.

Threshold
The beginning of that portion of the runway usable for landing.

Threshold Crossing Height
The height of the glide slope above the runway threshold.

Touch-and-Go
An operation by an aircraft that lands and departs on a runway without stopping or exiting the runway.

Touchdown Zone (TDZ)
The first 3 000 feet of the runway or the first third of the runway, whichever is less, measured from the threshold in the direction of landing.

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).

Transition
The general term that describes the change from one phase of flight or flight conditions to another; e.g., transition from enroute flight to the approach or transition from instrument flight to visual flight.
A published procedure providing navigation information from the enroute structure to the instrument approach procedure. Also includes SID/STAR transitions.

Vector
A heading issued to an aircraft to provide navigation guidance by radar.

Visual Approach
A visual approach is an approach wherein an aircraft on an IFR flight plan (FP), operating in visual meteorological conditions (VMC) under the control of ATC and having ATC authorization, may proceed to the airport of destination.

Visual Meteorological Conditions (VMC)
Meteorological conditions equal to or greater than the minima prescribed in Division VI of Subpart of CARs, Part VI, expressed in terms of visibility and distance from cloud.

Visual Separation
A means employed by a controller to separate aircraft. There are two ways of effecting visual separation:
(a) VFR – the airport controller issues clearances or instructions to assist the pilots in avoiding other aircraft; or
(b) IFR or CVFR – following a pilot’s report that the airport or traffic is in sight, the IFR controller issues the clearance and instructs the pilot to maintain visual separation.

Way Point (WP)
A specified geographical location used to define an area navigation route or the flight path of an aircraft employing area navigation.

Wind Shear (WS)
A change in wind speed and/or wind direction in a short distance resulting in a tearing or shearing effect. It can exist in a horizontal or vertical direction and occasionally in both.