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Flight Path

Design

1. The flight paths for the new Hong Kong International Airport (HKIA) were developed through careful studies. In accordance with international standards and recommendations, their development took into account runway alignment, terrain environment and obstacle clearances, location of navigation aids, aircraft operating criteria, environmental consideration, airspace coordination with nearby airports, etc. Hong Kong is small in size and hilly in topography. It is not possible to design flight paths that are in compliance with international aviation safety requirements on the one hand and completely clear of all residential developments on the other. When Civil Aviation Department appointed international aviation experts to assist in the planning of the flight paths for the new airport in 1994, various factors had been taken into account, and in-depth studies were conducted before the current flight procedures were published for use.

Arrivals

2. The HKIA has 2 parallel runways (commonly called the North Runway and the South Runway) which run northeast to southwest. At present, the two runways are normally operated in a segregated mode, i.e. the South Runway dedicated for departures and the North Runway for arrivals (with the exception of cargo flights and the Government Flying Service’s aircraft which for operational reasons will normally use the South Runway for landing). However, there are circumstances where the airport may be operated with a single runway, for example, in the event of runway blockage or during scheduled maintenance periods at night.

3. The direction from which aircraft land at HKIA mainly depends upon the wind direction. For safety and operational reasons, aircraft generally land into the wind. When the wind is from the west or southwest (which is prevailing in summer), aircraft will approach HKIA from the northeast overflying Tseung Kwan O, Sai Kung, Ma On Shan, Shatin and Tsuen Wan (including Sham Tseng and Tsing Lung Tau). When the wind is from the east or northeast (which is prevailing in winter), aircraft will approach HKIA from the southwest (over water).

4. The map in Appendix A(Open with new window) shows the arrival flight paths to HKIA.

Departures

5.  The direction in which aircraft depart from HKIA also depends upon the wind direction. For operational reasons, aircraft generally take off into the wind. When the wind is from the west or southwest, aircraft will depart from HKIA initially towards the southwest until it is about 7 nautical miles from the runway where it will make a left turn. Depending on its destination, an aircraft may turn towards the east and pass over Hong Kong Island and Kowloon Peninsula, or turn towards a northerly direction, passing over the New Territories at a relatively high altitude.

6. When the wind is from the east or northeast, aircraft will depart from HKIA towards the northeast until it reaches Ma Wan where, depending on flight destinations, it may turn south over West Lamma Channel, or proceed to the southeast passing over Tsing Yi, the southern part of Kowloon Peninsula (such as Tsim Sha Tsui and Hung Hom) and the northern part of Hong Kong Island (such as North Point, Shaukeiwan and Chai Wan). Aircraft destined for mainland may overfly the New Territories but would be at a relatively high altitude.

7. The map in Appendix B(Open with new window) shows the Standard Instrument Departure (SID) tracks followed by departing aircraft from the South Runway of HKIA. SIDs are a set of standard procedures which pilots are required to follow in the absence of being given alternative instructions by an air traffic controller (ATC). Their primary purpose is to enable the efficient transition of departing aircraft from the airport to the upper level airways. Pilots are required to follow these routes unless instructed otherwise by ATC. For the efficient management of limited airspace, ATC may give pilots a more direct route to their destination or a radar heading for separation with other traffic.

8. It should be noted that an aircraft in flight cannot follow a track precisely like a train running along a railway track. There are many factors that may affect the aircraft's flown track - the wind speed and direction relative to the aircraft's intended flight path, the performance characteristics of the aircraft, tolerances in navigational aids and different piloting skills and techniques etc. In practice, the flown tracks may deviate either side of the nominal center line shown in the map in Appendix B(Open with new window). Past studies have shown that the majority of aircraft follow the assigned routes within 1.5 km either side of the nominal center line.