WIND TUNNEL INVESTIGATION OF AN ASPECT RATIO 10 TANDEM WING AIRCRAFT CONFIGURATION IN GROUND EFFECT. PART I. LONGITUDINAL CHARACTERISTICS

Abstract : Subsonic wind tunnel test results obtained to determine the lateral aerodynamic characteristics of a tandem wing aircraft model in and out of ground effect are given. Test variables included model height above a ground board, model angle of attack, model angle of sideslip, and center-of-gravity location. Ground effect causes large sideslip-induced rolling moments (dihedral effect) on the model, which can be moderated by altering the size of the vertical tail. It is also possible that the large dihedral effect would be moderated by the roll stiffness term. However, roll stiffness data were not obtained for this model. (Author)