ENG-2001 — Page 334

TRANSPORT

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Shenzhen, Zhuhai and Macau, and to enhance ATC co-ordination arrangements among these airports.

Satellite-Based Communications, Navigation and Surveillancel

Air Traffic Management (CNS/ATM) Systems

The CAD plans to convert the current ground-based ATC systems to satellite-based Communications, Navigation and Surveillance/Air Traffic Management (CNS/ATM) systems by around 2016. Given the scale and complexities of the CNS/ATM systems, the work will be implemented in three phases as follows:

Study Phase Systems Study and Analysis (1999-2004)

Trial Phase CNS/ATM Trial and Evaluation (2000–2007)

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Implementation Phase CNS/ATM Implementation and Transition (2003–2016) Studies and trials of these next-generation ATC systems continued in 2001. With favourable feedback from the IATA, airlines and pilots, Digital-Automatic Terminal Information Service (D-ATIS) and Digital-Meteorological Information for Aircraft in Flight Service (D-VOLMET) were put into operational use on April 19 to disseminate airfield and meteorological information to aircraft via data links. Furthermore, upon the satisfactory operational trial in the delivery of Pre-departure Clearance to aircraft over data links, the service was also launched for operational use on December 4.

By eliminating the need for pilots to manually copy down important ATC information and messages, which were available previously only by voice communication, these new services employing digital technologies improve data accuracy, reduce the workload of pilots and controllers, enhance operational efficiency, and alleviate radio frequency congestion.

To gain operational experience, technical trials on an Aeronautical Telecommunication Network and an Air Traffic Services Message Handling System were conducted by the CAD with its counterparts in Thailand, Japan and Australia during the year, with encouraging results. Further trials on other CNS/ATM system elements are scheduled for 2002.

Aircraft Noise Management

In Hong Kong, impact caused by aircraft noise is assessed on the basis of the internationally accepted 'Noise Exposure Forecast (NEF) Contour'. The determination of the contour takes into account factors including the decibel levels of aircraft noise, the tonal characteristics as well as the duration and frequency of overflying flights at different times of the day. The standard currently adopted in Hong Kong is the NEF 25 contour, which is more stringent than the standards. adopted by some other airports.

The Government is mindful of the concern of some residents about aircraft noise. The CAD continued its effort in exploring and implementing all practicable aircraft noise mitigating measures. These include noise abatement take-off and landing procedures, prohibition of landing/take-off of relatively noisy aircraft at night and, whenever possible, use of flight paths which cover fewer residential areas. Furthermore, a plan is being implemented to further expand and upgrade the existing computer-based aircraft noise and flight track monitoring system to enhance its