Methodology to study the comfort implementation for a new generation of hydrofoils

Among the high speed crafts to be used as ferries, hydrofoils are considered the best solution to obtain high speeds and to reduce ship motions with the consequent comfort for passengers; in fact as long as the wave heights allow the hydrofoils to fly above the sea level the floating hulls are not effected by the sea conditions. It is important to underline that, in order to achieve the required performances, the construction techniques must be carefully controlled and refined because there are also some structural problems to be faced and solved to obtain a weight reduction. This study shows the results of a complete series of test, in towing tank and at sea, performed by the authors on a new class of hydrofoils designed and built by an italian line. This research refers, in particular, to the fleet of The Liberty Lines, as they are the most important operators in the world for passenger hydrofoils, with more than 30 units, constantly updating them and recently developing a brand with a new series of semi submerged wings to face the typical defects characterizing this type of naval unit.) where fundamental points have been analyzed such as: the wing hydrodynamic optimization by means of model testing; the structural study of new wing systems and the update of the production processes with new construction techniques, and the improvement of the passengers comfort as for accelerations and vibrations. The tests have demonstrated a significant gain for new projects.