Wake Vortex Profiling by Doppler X-band radar : Orly trials at Initial Take-Off & ILS interception critical areas

In order to improve the capacity of airports in view of the expected increasing amount of traffic the knowledge about the safety issues caused by wake vortices has to be improved. The final goal is to build up a wake vortex alert system to ensure the application of appropriate but not oversized safety distances in all weather conditions. Lidar systems are able to deliver very accurate data, but are also sensitive to the weather conditions like rain and fog. We did trials with the X-band radar BOR-A 550 on Orly Airport in November, 2006 at initial take-off and in October 2007 at ILS interception area. Continuous detection, characterization (strength : circulation), and profiling (age : young/mature/old/decaying) capabilities of wake vortices up to a range of 700 m have been proved in clear air and rainy weather. Opportunity detection of wake vortex was also obtained at long range until 7 Km in clear air. The Doppler resolution of around 0.2 m/s used with regularized high Doppler resolution techniques is able to characterize the wake vortex speed distribution in detail. X-band radar is a full-fledged alternative, which can make a significant contribution to a wake vortex alert system.