Monitoring Wind, Turbulence and Aircraft Wake Vortices by High Resolution RADAR and LIDAR Remote Sensors in all Weather Conditions
Résumé
Air flows in the troposphere have a major impact on air traffic safety and operations. By air flows, several phenomena can be distinguished with different spatial and temporal characteristic scales: the mean wind itself, its rapid fluctuations, called turbulence, and wake vortices which are structured motions generated by each aircraft. At low altitudes, during take-off or landing phases, distance separations between aircrafts that limit today airport capacities were set up forty years ago to prevent the rik of wake vortices encounters in worst conditions. These out of date distance separations must be optimized since strength and lifetime of wake vortices vary a lot with weather conditions, like winds and turbulence. At high altitudes, during en-route flight phase, wake vortices as well as clear air turbulence can have a dramatic impact on aircraft safety. In this study, the way to measure wind, turbulence and wake vortices with new remote sensing techniques, 1.5 micron Coherent Doppler LIDAR, X-Band RADAR, and UV direct detection LIDAR, is detailed for ground-based or airborne applications. Sensor simulation tools and post-processing algorithms have been developed to retrieve wind, turbulence, especially EDR (eddy dissipation rate) and wake vortices parameters from sensors data and to assess their accuracy