What happens if you take a rubber dinghy and put the foils on it? Everything! We tried it on our skin in the icy waters of Lorient, France. An inflatable boat Zodiac with foils already available on the market, developed by Seair. The wings are electronically fed into the centre console and allow high-performance navigation.
One Zodiac 5.50 as standard has been modified by Seair with two J-shaped foils that have the horizontal part, which gives the upward thrust, so to speak, facing outwards from the hull (as opposed to what, for example, happened to the America’s Cup sailing catamarans).
After 15 knots the boat actually starts to “fly” with the foils. No exaggerated motorization is necessary, just an engine between 80 and 115 horses. With foils, even when sailing at already interesting speeds, let’s say 20 knots, the “perceived” speed seems lower. This is because it rises a few centimetres above the water and remains stable even with the wave.
The foil shaft slides up and down through a hole in the bottom of the hull and continues inside the steering console. The adjustment of the foils from the rest position, with the tip, the horizontal part, near the hull, to the navigation position, is done by means of electric controls, as well as the angle of incidence of the foil with the water. In conditions of foiling navigation, the keel remains at about 25 cm from the water surface, both for the thrust of the two foils and for the fin placed at the end of the foot of the outboard engine.
Navigation is therefore very comfortable (you can’t hear the waves), even in rough seas the passage of the wave becomes very soft, but above all the fuel saving is exceptional: on average the consumption (measured by comparing an identical model, but not transformed) is 30% lower, reaching up to 50% savings in ideal conditions.