Low-speed aerodynamic characteristics improvement of ATR 42 airfoil using a morphing wing approach

This paper presents a morphing wing technique for extending laminar flow over the airfoil of the ATR 42 regional transport airplane. The objective is to reduce aerodynamic drag by delaying the transition from laminar to turbulent flow over the airfoil upper surface. The optimization of the airfoil shape is performed for several incompressible subsonic regimes, using a genetic algorithm tool, coupled with the subsonic aerodynamic solver XFOIL. A reduction of the drag coefficient with up to 26.73% and a delay in the transition point of up to 24.81% has been achieved.