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Functions of Various Air Traffic Control Equipment / Facilities for the HKIA


Air Traffic Management System (ATMS)

ATMS processes the flight plan and surveillance data from various surveillance signal input sources, including primary and secondary surveillance radars as well as ADS-B system, to present details of the aircraft information (e.g. aircraft position, altitude, callsign, ground speed, aircraft category, etc.) on the screen of air traffic control working positions to facilitate the management of air traffic by the air traffic control officers.

ATMS can handle 8 000 flight plans per day and can simultaneously monitor 1 500 air or ground targets, which are 5 times and 1.5 times of the previous system respectively, making it fully capable of coping with anticipated air traffic growth.

In addition, ATMS includes three sub-systems, namely Main system, Fallback system, and Ultimate Fallback System (UFS). The Main and Fallback systems are identical systems. UFS is an independent system with software and system configuration completely detached from the Main and Fallback systems. The purpose of this design is to reduce the risk of complete system breakdown due to failure of both the Main and Fallback systems, which safeguards flight safety. ATMS ensures extremely high availability through multiple layers of infrastructures such that in case of temporary issues in a single system, air traffic controllers could continue to provide the air traffic services seamlessly in another system. ATMS is provided with the advanced information technologies, including enhanced flight information and data processing, more precise flight trajectory prediction functions, multi-surveillance tracking technology, advanced automatic safety net features, weather prediction and display, electronic flight strip, silent coordination ability between ATC Centre and ATC Tower, etc.

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Air Traffic Service Data Management System (ATSDMS)

ATSDMS includes (i) an enhanced Air Traffic Control Data Network, which is the communications backbone for all new ATC systems and (ii) an Operational Information Database System, which provides an integrated operational displays for real-time air traffic services information.

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Aeronautical Information Management System (AIMS)

AIMS is an information management system used for the generation, distribution and storage of Notices to Airmen, as well as management of flight plans and other aeronautical information for use by air traffic flight services officers and pilots.

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Aeronautical Messaging System (AMS)

AMS consists of two major components - Aeronautical Telecommunications Network (ATN) Router System and Regional Operational Meteorological Bulletin Exchange (ROBEX) System.

The ATN Router System supports the exchange of air traffic services messages among the Air Traffic Services Message Handling Systems (AMHS) in Hong Kong and the adjacent Communications (COM) Centre, while the ROBEX System is for storing meteorological messages and disseminating them to the neighbouring Communications (COM) Centre in the Asia Pacific Region.

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Communication Backbone (CB)

CB is a communication network consisting of Synchronous Digital Hierarchy rings and Microwave links interconnecting the communication, navigation, surveillance and air traffic management systems located in the CAD Air Traffic Control Building/Tower and outstations in various areas of Hong Kong.

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Voice Communication Switching System (VCSS)

VCSS is a computerised voice communication system for direct communication between pilots and air traffic control officers, and between air traffic control working positions in the ATC Centre, ATC Tower and Rescue Coordination Centre, by using pre-set aeronautical frequencies, direct communication lines and telephone lines.

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Digital Recording System (DRS)

DRS is used for 24-hour recording of the air/ground radio and telephone communication channels between ATC Centre/ATC Tower and other external organisations. The recordings are essential for incident/accident investigation and training of air traffic control officers.

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Automatic Terminal Information System (ATIS)

ATIS is a VHF broadcasting system for continuous dissemination of vital information (e.g. updated airfield, meteorological and navigational aids serviceability information, etc.) to flights departing from or arriving at HKIA. Public can also gain access to the information at telephone no. 3141 2820 and 3141 2705.

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Automatic VOLMET Broadcast System (AVBS)

AVBS is used to automatically broadcast at regular intervals the pre-recorded meteorological information for various airports including Hong Kong and the neighbouring aerodromes (e.g. Guangzhou, Naha, Taipei, etc.).

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Air Traffic Services Message Handling System (AMHS)

AMHS is a ground-to-ground communication system for supporting air traffic services message exchange among Hong Kong and overseas ATC centres, enabling timely and reliable dissemination of aeronautical information over Aeronautical Telecommunications Network and Aeronautical Fixed Telecommunication Network to secure flight safety and efficiency.

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Primary Surveillance Radar (PSR)

PSR detects and provides both the range and bearing information of an aircraft within its effective coverage by radio wave reflection. Depending on the operational need and external environmental conditions, the coverage may reach 80NM for approach control or 200NM for en-route control purpose. A short range PSR is installed at Sha Chau to detect aircraft operating within the approach and departure areas of the HKIA.

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Secondary Surveillance Radar (SSR)

SSR provides, after processing, the range, bearing, altitude and callsign of an aircraft. Depending on the operational need and external environmental conditions, the coverage may reach 250NM. It can provide more useful information than PSR but is subject to the proper functioning of the aircraft's transponder. To provide the best accuracy of aircraft position, it is usually paired with a PSR for air traffic control purpose.

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Advanced Surface Movement Guidance and Control System (A-SMGCS)

A-SMGCS employs both the multilateration and Automatic Dependent Surveillance-Broadcast (ADS-B) technologies for enhanced surveillance of aircraft and vehicle movement in the airfield, and provision of conflict and runway incursion alerting functions for improved flight safety and efficiency.

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Automatic Dependent Surveillance - Broadcast (ADS-B) System

ADS-B System receives and processes the messages broadcasted from aircraft, covering the aircraft identification, position, altitude, air speed, and heading, etc.

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Surface Movement Radar (SMR)

SMR is mounted on the top of South ATC Tower for surveillance of aircraft and vehicles on the runways and taxiways. The accurate information provided enables the air traffic control officers to maintain a smooth flow of traffic during low visibility conditions.

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Radar Simulator (SIM) System

Radar Simulator (SIM) System is a replica of the ATMS and is used for the training of air traffic control officers as well as the evaluation of air traffic control procedures.

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Control Tower Simulator (CTS)

CTS uses the advanced imaging technology to simulate the airport environment, including day or night, good or bad weather conditions, and aircraft emergencies. It is an effective tool for the training of air traffic control officers.

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Instrument Landing System (ILS)

ILS provides accurate azimuth and descent guidance signals for use by aircraft landing on the runway under normal or adverse weather conditions. The equipment serving both approach directions of the south runway has been certified for Category II operation with a decision height of 15m. For the north runway, similar Category II ILS is installed for aircraft approaching from the southwest while Category III ILS, which supports blind landing from northeast direction, has also been provided.

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Doppler Very High Frequency Omni-directional Radio Range and Distance Measuring Equipment (DVOR/DME)

DVOR/DME provides bearing and distance information to aircraft, and to define air traffic control routes for en-route, terminal and instrument approach/departure procedures. They are installed at Tung Lung. Cheung Chau, Lung Kwu Chau and Siu Mo To to support departure and missed approach flight paths of the HKIA.

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High Frequency/Very High Frequency (HF/VHF) Communication Equipment

This includes the radio and signal transmitters and receivers operating on various frequencies used for both the long-range and short-range air/ground communications with aircraft. They are installed at Cape D'Aguilar, Mount Butler, Victoria Peak, Tai Mo Shan, North Lantau, Mount Parker, Beacon Hill, and on-airport sites.

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Non-directional Beacon (NDB)

NDB is installed at the southwest end of the runway promontory to provide additional track guidance to aircraft departing from the runway.

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Microwave Link System (MLS)

MLS conveys radar and air/ground communication signals, equipment status and remote control signals between various CAD radars, navigational aids and communication stations, the ATC Centre, ATC Tower and Watchkeeping Control Centre.

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Master Clock System (MCS)

MCS sets the time standard according to the time reference derived from the Global Positioning System and Hong Kong Observatory. It is also used to synchronise the time among various ATC systems of the HKIA, as well as to display standard time for air traffic control purpose.