This paper describes the development of an innovative 'Proper Orthogonal Decompositionbased Reduced Order Design Scheme' method to reduce the number of shape design variables needed for an efficient geometry optimization of air vehicles, while maintaining the generality of the design space. This POD-RODS method is based on the Proper Orthogonal Decomposition technique of extracting POD modes from a family of candidate configurations and constructing a reduced order design space, in which the POD coefficients act as the new shape design variables. The candidate configurations can be selected based on a designer's past experience and entailing intuition. Established with the goal of developing a prototypical design process for unconventional air vehicle shape design, the POD-RODS method, when linked with a streamlined multi-disciplinary optimization framework, offers a computationally efficient and cost effective methodology for the conceptual design and configuration development of air platforms. The geometry optimization scheme developed herein is demonstrated for its robustness on a supersonic tailless air vehicle, which offers a medium level of complexity and a much challenging design space to fully utilize the POD-RODS method. Nomenclature b in , b out inboard wing half-span, outboard wing half-span C L , C Lg , C Lmax total lift coefficient at cruise condition, at ground run and at take-off, respectively C L , α derivative of total lift coefficient w.r.t. angle of attack at cruise condition C D , C Dg total drag coefficient at cruise condition and at ground run, respectively C M total moment coefficient at cruise Mach number and altitude C M,α derivative of total moment coefficient w.r.t. angle of attack at cruise condition c m , c t chord at wing-crank, wing-tip chord c f specific fuel consumption H altitude M Mach number N z gravitational acceleration in z-direction S wing reference area S T O take-off distance T, T a0 temperature at cruise altitude, nominal temperature at sea-level T 0 static thrust

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This paper describes the development of a consistent finite element formulation and an efficient solution procedure to investigate the nonlinear flutter of curved panels at yawed supersonic flow and at elevated temperatures. A finite element frequency domain method is developed to predict the preflutter behavior and the flutter onset of curved panels subjected simultaneously to aerodynamic and thermal loading. The Marguerre plate theory, the von Kármán large deflection theory, quasi-steady first-order piston theory, and quasi-static thermoelasticity are used in the formulation. The principle of virtual work is applied to develop the equations of motion of the fluttering system in structural degrees of freedom. The Newton-Raphson method is used to determine the panel deflection under the static thermoaerodynamic loading, and an eigenvalue solution is employed for predicting the flutter critical dynamic pressure for curved panels of different height-rises. Flutter coalescence frequencies and damping rates of the fluttering curved system are investigated for three-dimensional curved panels under increasing dynamic pressure and uniform or linearly varying temperature gradient loading. The results showed that the preflutter panel behavior and the flutter onset are significantly altered when temperature effects are included in the formulation.

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