The Wow!10too hydrofoil is fixed in position, but can be slid out for very light weather. It curves upward and outward from the waterline. The attack angle is +6º. To adjust the attack angle the skipper moves his/her body forward or aft. To increase the foil depth of immersion the skipper moves to leeward. When sailed flat, the edge of the hydrofoil where the hydrofoil enters the hull is just below water level. The gunwales, forward and aft of the hydrofoil, consist of buoyant volumes which provide anti-heeling assistance by increasing the lever arm of the hiking anti-heeling force. The beam at the waterline is narrow to reduce form drag. The bottom is flat to enhance planing. Sail standard area is 119 square feet (11 sq meters). Options for sail areas of 75 and 96 square feet are also available. Shorter hydrofoils are available for these options The hull weight is approximately 45 lbs. The hydrofoil decreases the apparent weight of the boat, reducing skin friction and form drags. The boat is about 10 feet long.
An alternative rig is also possible which uses the mast from an 11 rig with a raised boom and the sail from a 9 rig. In this situation the boat can be sailed standing up, combining the features of a windsurfer and a dinghy.
The image above shows rig 9. The image below illustrates the operation of anti-heeling features of the boat. It can be seen that the level arm of the hiking moment increases sharply to port as the hydrofoil immerses and as the aft and fore gunwale cavities engage the water. The value of the anti-heeling lifting force varies with boat speed. The angle of heel varies with the hiking position of the skipper.