The low level wind shear alert system (LLWAS) adopts multiple devices to jointly detect the winds and comprehensive weather information at the airport. It can provide continuous and real-time measurements of the atmospheric horizontal wind speed, wind direction, vertical air flow and turbulence intensity from the ground to the height of 3km. The system has the ability of real-time monitoring disastrous weathers, such as meso-and-micro-scale windstorm, low-altitude wind shear, etc. In the critical low-altitude region from the ground height of 20m to 600m, this system can provide high precision fine three-dimensional wind measurements under the weathers conditions such as clearness, low visibility, low rainfall, etc., to provide effective measurements for ensuring the meteorological safety of the airport.
Three-dimensional wind field will be available, with wind data of high precision and high spatial and temporal resolutions and more useful information. All facilities are mobilized for quick installation and system setup. The system setup is highly flexible, and has low field requirements of installation. This system adopts the multiple instruments for joint detection. It has ability of measuring winds under complex weather conditions, such as clear sky, and low visibility or rainfall conditions, etc. The system can accommodate all-weather situation. The system includes Doppler wind lidar system, which can achieve high-precision regional detection along the direction of runway, and particularly can detect the wind shear above the runway that is scheduled airplane departure or landing. The wind shear warnings given by the system is in accordance with ICAO ANNEX 11.