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.

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.

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

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

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.

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.

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

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

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

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.