Lift augmentation of a low-aspect-ratio thick wing in ground effect

The upper surface cross-sectional profile of the wing body was generated through a consideration of a modified deck arrangements of an existing commercial high-speed catamaran while keeping the bottom surface flat. The top and middle decks were moved forward so that the maximum camber was obtained at 25% of chord from the leading edge. The wing body was designed using the modeling package CATIA, and then NC milling codes were generated from CATIA facility. The six-component balance was calibrated for lift, drag, and pitching moments. The resulting calibration curves were then used for the determination of lift, drag, and pitching-moment coefficients. The leading edge of the ground board was elliptical in shape, and the trailing edge was tapered to ensure smooth and attached flow around it. The ground board was secured to the top of the wind-tunnel test section using Brooker bolts fastened by locknuts. Diagonal struts were used to prevent board vibration and buckling during wind-tunnel operation.