Aircraft spoiler effects under wind shear

Abstract

Effects of symmetrical and nonsymmetrical spoiler configurations on an aircraft model under wind shear are experimentally studied. Lift, drag, and side forces in addition to pitching, yawing, and rolling moments are investigated for various angles of attack, sideslip angles, spoiler deflections, and wind shear velocity ratios. The results substantiate that spoiler deflection increases the drastic lift reduction caused by wind shear, especially at low angles of attack. Wind shear also tends to intensify the spoiler effect on the side force and yawing moment, while it affects the resulting rolling moment only at high angles of attack. Spoiler deflections, however, have practically no effect on the aircraft stability margin which normally increases by the presence of wind shear.