MASC – a small Remotely Piloted Aircraft (RPA) for wind energy research

Abstract. Originally designed for atmospheric boundary layer research, the MASC (Multipurpose Airborne Sensor Carrier) RPA (Remotely Piloted Aircraft, also known as Unmanned Aerial Vehicle, UAV) is capable of making in-situ measurements of temperature, humidity and wind in high resolution and precision. The autopilot system ROCS (Research Onboard Computer System) enables the aircraft to fly pre-defined routes between waypoints at constant altitude and airspeed. The system manages to operate in wind speeds up to 15 m s⁻¹ safely. It is shown that a MASC can fly as close as one rotor diameter upstream and downstream of running wind turbines at these wind speeds and take valuable data of incoming flow and wake. The flexible operation of an RPA at the size of a MASC can be a major advantage of the system compared to tower measurements and remote sensing in wind energy research. In the project "Lidar Complex" comparisons of RPA measurements with lidar systems and tower measurements are carried out at two different test sites. First results, including turbulence and wake measurements, from a campaign in autumn 2013 are presented.