1. Tecnalia Electric Aircraft, Tecnalia Research and Innovation, 20009 San Sebastian, Spain
2. Automatic Control Group (ACG), Institute of Research and Development of Processes, Dept. Aut. Control and Systems Eng., University of the Basque Country (UPV/EHU), Po Rafael Moreno 3, Bilbao 48013, Spain
3. Promotion and Subsides Area, Basque Energy Board (EVE), 48011 Bilbao, Spain