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Functions of Various Air Traffic Control Equipment for the Airport
Radar Data Processing & Display System (RDPDS), Flight Data Processing System (FDPS) and Simulator System (SIM) -- (The heart of the air traffic control system)
RDPDS processes the radar data from various primary and
secondary radars to present the aircraft position and its
related information, e.g. aircraft callsign, altitude, ground
speed, aircraft category, etc. on the radar display. This
information is used by air traffic controllers to control
the approach/departure, terminal and en-route traffic.
The SIM is a replica of the operational system and is used for the training of air traffic controllers and evaluation of air traffic control procedures.
This type of radar detects
and provides both range and bearing information of an aircraft
within its effective coverage by radio wave reflection. Depending on the application,
the coverage will be within 80NM for approach control or
within 200NM for en-route control purpose.
This type of radar provides,
after processing, the range, bearing, altitude and identity
(callsign) of an aircraft. The coverage can reach 250NM.
A SSR 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 targets, the SSR is usually paired with a PSR
for air traffic control purpose.
This radar is mounted on top of the Aerodrome Control Tower for surveillance of the movement of aircraft and vehicles on the runway and taxiways. The accurate information provided enables the tower controller to maintain a smooth flow of traffic during low visibility or darkness.
The A-SMGCS employs both the multilateration and Automatic Dependent Surveillance-Broadcast (ADS-B) technologies for enhanced surveillance of aircraft and vehicle movements on the airfield, and provision of conflict and runway incursion alerting functions for added air traffic control safety and efficiency.
This simulator uses the latest imaging technology to simulate the airport environment, during day or night, and under good or bad weather conditions. It is an effective tool for the training of air traffic controllers on aerodrome control.
This is a separate radar simulator used for area control and radar control training of controllers.
A standard ICAO precision landing aid to provide accurate azimuth and descent guidance signals for use by aircraft for 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 equipment is installed for aircraft approaching from the southwest while more precision Category III equipment, which supports blind landing from northeast direction, has also been provided.
Doppler Very High Frequency Omni-directional Radio Range and Distance Measuring Equipment (DVOR/DME) System
Standard ICAO radio navigational aids used
to provide bearing and distance information to aircraft
and to define air traffic control routes for en-route, terminal
and instrument approach/departure procedures.
A database and information display system used for the generation, distribution and storage of Notices to Airmen (NOTAM), meteorological information and forecasts, and other aeronautical information for use by air traffic service operators and pilots. The information can be accessed via computer terminals.
A standard ICAO ground-to-ground communication system for the exchange of air traffic control messages within the Aeronautical Fixed Telecommunication Network (AFTN) between Hong Kong and overseas airports.
This includes the radio and signal transmitters and
receivers operating on various frequencies used for both
long-range and short-range air/ground communications with
This is a computerised voice communication system between pilots and air traffic controllers, and between air traffic control positions in the Air Traffic Control Centre, Aerodrome Control Tower, Rescue Coordination Centre and Aeromobile Centre by using pre-set switching and distribution of various aeronautical frequencies and direct communication lines.
The system is used for 24-hour recording of over 500 air/ground radio communications and telephone communication channels between Air Traffic Control Centre of CLK and other external agents. The recordings are essential for the investigation of aircraft incidents and accidents.
A VHF broadcasting system for continuous dissemination of vital information (such as updated airfield, meteorological and navigational aids serviceability information, etc.) to pilots departing from or arriving at HKIA. Public can also gain access to the information at telephone no. 3141 2820 and 3141 2705.
The system is used to broadcast automatically recorded meteorological information for various airports including Hong Kong and the neighbouring aerodromes e.g. Guangzhou, Naha, Taipei, etc. at regular intervals.
The system is used for conveyance of radar and air/ground communication signals, equipment status indication and remote control signals between various remote CAD radar, navigational aid and communication stations and the operation and maintenance centers at the HKIA.
A centralized clock system in the ATCX to set the time standard according to international time reference derived from the Global Positioning System (GPS). It is also used to synchronise the time signals between all elements of the CLK ATC system, as well as to display standard times for controllers' reference.
A standard radio navigational beacon installed at the southwest end of the runway promontory to provide additional track guidance to aircraft departing from the runway.
In the event
of serious fire or hazardous incidents which render the
Air Traffic Control Complex (ATCX) not able to perform its original function, normal
air traffic control (ATC) services will be severely disrupted.
To maintain the continuous ATC services, a Backup Air Traffic
Control Complex (BATCX) equipped with all essential backup
ATC facilities will be activated. These backup facilities
can support about 30 per cent air traffic control handling
capacity to maintain a safe and orderly flow of air traffic.
The PRM is basically a Monopulse Secondary Surveillance Radar (MSSR) that employs electronically-scanned antennas configured in a circular array. Compared with conventional SSR, the PRM has no scan rate restrictions, thus capable of providing a much faster update rate (up to 0.5 second), better target presentation in terms of accuracy, resolution, and track prediction. The system is designed to search, track, process and display SSR equipped aircraft within an airspace of 32 nautical miles in range and 15,000 feet in elevation.
A new generation of ground-to-ground message introduced by ICAO for exchange of Air Traffic Service messages with enhanced functions and quality of service