The parameter α represents the angle of attack. The parameter 0DC represents the parasite drag due, for example, to skin friction. The parameter D C∂ represents induced drag coefficient. While hydrodynamic coefficients depend on glider geometry such as the shape and the incidence angle of wings, they also depend on the flow characteristics, which correlate to the Reynolds number[6]. According to above discuss, we know the lift/drag ratio of the glider is