Application of Navier-Stokes aeroelastic methods to improve fighter wing maneuver performance

An aeroelastic analysis method, based on three-dimensional Navier-Stokes aerodynamics, has been applied to improve the performance of fighter wings operating at sustained maneuver flight conditions. The scheme reduces the trimmed pressure drag of wings performing high-g maneuvers through a simultaneous application of control surface deflection and aeroelastic twist. The aerodynamic and structural interactions are decoupled by assuming an aeroelastic twist mode shape and optimizing the aerodynamic performance based on this aeroelastic mode. The wing structural stiffness properties are then determined through an inverse scheme based on the aerodynamic loads and desired twist at the maneuver flight condition. The decoupled technique is verified by performing a fully coupled aeroelastic analysis. One of the more important features of this application, over and above improved maneuver flight performance, is that the wing performance at cruise conditions is not compromised. Thus, this method represents a multiple-point wing design capability utilizing computational aerodynamics methods and aeroelastic tailoring.