Impact of a Supercritical Airfoil on the Transonic Aerodynamic Performance of an M-Wing

Between 1950 and 1965, the National Advisory Committee for Aeronautics (NACA) tested a swept wing derivative known as an “M-wing”, which uses an aft and forward sweep combination on a single semi-span. The configuration showed improvements in transonic aerodynamic efficiency, longitudinal stability, and a more controlled pitch break compared to an A-wing with 45 degrees of aft sweep. While an improvement over traditionally swept wings, the tested geometry was limited to a symmetric airfoil not optimal for transonic flight. As such, this paper aims to investigate the impact of the more modern supercritical airfoil on the transonic performance of, and flow behavior around, the M-wing. Simulations were performed at Mach 0.7, 0.98 and 1.08 at angles of attack (AOA) of 4, 8, 12, and 16 degrees. Contrary to expectations, results suggest that the supercritical M-wing saw an efficiency decrease across all 12 Mach/AOA combinations when compared to the symmetric M-wing. Using a supercritical airfoil lead to the production of more intense and controlled leading edge vortices, resulting in both higher Cl and Cd values. While more information is needed to confirm the observed trends, preliminary results show that using a supercritical airfoil cannot improve the M-wing’s performance within the Transonic regime.