Flow separation is one of the major problems affecting the performance of all airfoils under a high angle of attack. Several passive flow mechanisms have been investigated to limit this phenomenon and improve the aerodynamic efficiency of the airfoil by increasing the lift force while decreasing the drag force associated with it. This study investigates the application of surface bumps over both the suction and pressure sides of the NACA-0018 airfoil at low Reynolds number of 500,000. The bump shapes resemble the shape of the Hawk which does not show a smooth profile in nature. The bumps are introduced in the form of sine waves with different amplitudes and periods. Bumps on each side have been investigated separately, the optimum amplitude and period are determined, the two optimum parameters were joined together forming a new airfoil shape. It was found that this approach limits separation at the stall angle and reduces the drag force as a result of the bumps on the suction side. The bumps on the pressure side were found to enhance the lift force as high-pressure spots are formed, which increases the differential pressure. Glide ratio improvement of 17% was reached using the modified airfoil.