Latest developments of windshear alerting services at the Hong Kong International Airport

Low-level windshear and turbulence could be hazardous to the operation of the aircraft. In the last 10 years or so in the operation of the Hong Kong International Airport (HKIA), the detection and alerting of low-level windshear has been continuously enhanced by the Hong Kong Observatory, including the introduction of sophisticated instrumentation and detection algorithms to alert pilots about the presence of windshear, and the use of more objective data in the development and verification of the windshear alerting services. This paper summarizes these development efforts in the recent years.

On the detection side, the LIDAR Windshear Alerting System (LIWAS) has been enhanced for the alerting of windshear over the departure runway corridors following the deployment of runway-specific LIDAR systems. A microwave radiometer has also been set up at the airport to detect temperature changes in the boundary layer of the atmosphere in association with terrain-disrupted airflow. Moreover, a short-range LIDAR is being tested in the detection of small-scale wind disturbances arising from buildings at the airport. Studies are also conducted in the calculation of turbulence intensity metric based on LIDAR and Terminal Doppler Weather Radar (TDWR) data.

On the data collection side, sophisticated algorithm has been developed in collaboration with the National Aerospace Laboratory in the Netherlands in the processing of Quick Access Recorder (QAR) data from commercial jets in establishing a more objective database of windshear and turbulence based on the flight data. The meteorological measuring equipment of a fixed-wing aircraft based in Hong Kong has also been upgraded to collect accurate meteorological data at high frequency for further tuning of the windshear and turbulence detection algorithms.

The various aspects in the enhancement of the windshear alerting services at HKIA would be reviewed in this paper.