On the flight performance impact of landing gear drag reduction methods for unmanned air vehicles / F. Götten, F. Finger, M. Havermann, C. Braun (Department of Aerospace Engineering, FH Aachen University of Applied Sciences, Aachen, Germany), F. Gómez, C. Bil (School of Engineering, RMIT University, Melbourne, Australia) ; Deutscher Luft- und Raumfahrtkongress 2018