Compressibility effects on aerodynamic characteristics of a Mars airplane is investigated at a low Reynolds number flight condition. The aerodynamic characteristics are evaluated by using Reynolds-Averaged Navier-Stokes simulations with SST κ—ω turbulence model and γ—Reθ transition model. Numerical results show that the lift coefficient increases as the Mach number increases at angles of attack of 2 to 6 degrees, but it decreased at angles of attack of 0 and 8 degrees. The drag coefficient also increased as the Mach number increased. The pitching moment coefficient significantly decreased as the Mach number increased. The main reason of these changes is that the reattachment point of the separated flow on the main wing moves to downstream due to the compressibility effect.
