Flight trials have begun around wind farms in Wales to test a technical fix to overcome the effect of wind turbines on airport and defence radar. Under current concerns to ensure aviation safety, all wind projects within line of sight of Ministry of Defence (MoD) or air traffic radar are opposed because the rotating blades of turbines can mimic an aircraft on radar screens as they move at speeds of up to 200 miles per hour at the blade tip. This has prevented developers from progressing potential projects in large swathes of the countryside. Radar technology experts BAE Systems have now designed the Advanced Digital Tracker (ADT) which, for the tests, will be fitted to a mobile MoD radar. It will be sited in Wales in an area where four wind farms of different turbine sizes, numbers and models will provide a rigorous test for the technology. Various types of aircraft will fly over the wind farms to test whether the ADT reduces clutter and false tracks on the radar screen from the turbines while still registering the aircraft clearly. BAE Systems' research was financed by the Department of Trade and Industry (DTI) and 18 developer members of the British Wind Energy Association (BWEA). Chris Tomlinson of the BWEA says: "This is the first major step towards developing a technology that can tackle the interaction of wind turbines and radar which currently leads to the sterilisation of a significant number of potential wind farm sites." Results from the trials will be available in October and if all goes to plan, the ADT could be on the market by the end of 2006.