Aerodromes

Definitions: Aerodrome: Any area of land or water designed for the arrival, departure, movement and servicing of aircraft.  This includes buildings, installations and equipment. Airport:  Any aerodrome which has a certificate. There are four kinds of aerodromes: 1. Certified for public use 2. Certified for private use 3. Registered aerodromes 4. Military aerodromes Manoeuvring Area: All parts of an airport intended for the landing, takeoff and movement of aircraft (for example, runways and taxiways). Apron:  This is an area for the loading and unloading of cargo and passengers, and the refuelling, servicing, maintenance and parking of aircraft. Note:  The pilot should report the landing of any aircraft to the airport operator. Runway Numbering Runways are numbered so that they match the magnetic bearing that they are aligned with, rounded to the nearest 10?.  The final zero is then dropped from the number. In the Northern Domestic Airspace, compasses do not work properly, so runways use true bearings. Large airports may have two or more runways parallel to each other.  In this case, the runway on the left is designated with its number and the letter "L" (meaning 'left') and the runway on the right is designated with its number and the letter "R" (meaning 'right').  If there is a third runway, the centre runway is designated with its number and the letter "C" for 'centre'. Runway Markings If runways are not paved (they are grass or snow or dirt), they are marked by pyramid or cone shaped markers.  In snowy areas, evergreen trees 4-5 feet tall are used. Paved runways have white centre lines and "threshold lines". Threshold lines mark the beginning and end sections of a runway. Taxiways Taxiways can be identified by the yellow centre lines.  They are assigned letters for identification, not numbers.  For example a taxiway may be called "Taxiway Alpha". A yellow line across a taxiway cannot be crossed without permission.  It is called a "hold short line", and keeps traffic from moving out onto a runway where other aircraft may be landing or taking off. Wind Indicators At airports, certain devices are used to help pilots estimate the strength of the wind.  The most commonly used device is a "windsock".  A wind sock can show the direction and approximate strength of the wind. A windsock will fly perfectly horizontal if the wind has a strength of 15 knots or more, and its tail will hang at an angle of 30? in a wind of 6 knots.  A windsock that is coloured with white and international orange stripes means that the airport is a certified airport.  A solid orange windsock is flown at all other airports. Aerodrome Traffic Procedures Aircraft do not normally fly directly to an airport and land.  When they reach the destination airport, pilots fly their airplanes in a pattern called a "circuit" which allows them to adjust their height above the ground and ensures a safe landing.  There are three parts to a basic circuit: downwind, base and final. On the downwind leg (or section) of a circuit, the airplane flies parallel to where it will be landing, but in the opposite direction.   On the base leg, a 90? is made and the aircraft flies closer to the runway.  On the last leg, called final, a second 90? is made to line the aircraft up with the landing area.  The aircraft then lands. At some airports, a "mandatory frequency" is published and must be used by all aircraft in the area.  You may see mandatory frequency abbreviated as "MF". NORDO You may remember that an aircraft flying without a radio, or without a working radio is designated as "NORDO" standing for NO RaDiO.  These aircraft use light signals to understand directions from air traffic control. Light Signals There are two sets of light signals used for NORDO aircraft. One for one the ground, and one for aircraft in flight.  They are: On the Ground Flashing green  - cleared to taxi Steady green  - cleared to takeoff Flashing red  - taxi clear of the landing area Steady red  - stop Flashing white  - return to starting point at the airport (hanger, etc) Blinking runway lights - vacate the runway immediately In the Air Steady green  - clear to land Steady red or red flare - do not land, continue in the circuit Flashing green  - recall, return for landing Flashing red  - airport unsafe, do not land Red pyrotechnical light -  do not land right now Aircraft should acknowledge these light signals by rocking the wings of the aircraft or flashing their lights.