Reducing Induced Drag and Maneuver Loads by Active Aeroelastic Alteration

Abstract

Induced-drag reduction and maneuver load relief are two recent benefits of active aeroelastic wing technology. Judiciously deflecting wing-edge flaps can alter an unfavorable force distribution aeroelastically. Active distribution matching control to reduce induced drag and active load alleviation control by reducing wing bending moments are such active aeroelastic wing applications. Kolonay and Eastep (“Optimal Scheduling of Control Surfaces on Flexible Wings to Reduce Induced Drag,” Journal of Aircraft, Vol. 43, No. 6, Nov.–Dec. 2006, pp. 1655–1661) posed a least-squares problem to match the calculated distribution to an elliptic distribution. Zink et al. (“Maneuver Trim Optimization Techniques for Active Aeroelastic Wings,” Journal of Aircraft, Vol. 38, No. 6, 2001, pp. 1139–1146) posed aircraft trimming as bending-moment minimization to provide external-load relief at the wing root. Analytic gradients, exact aeroelastic analyses, and closed-form trim solutions are unique features of the Automated Stru...