The hydrofoil is a craft where the weight is entirely supported by the submerged wings.

With low speeds, the hydrofoil behaves in a similar way to the fast hulls with resistance curves and power that increase with the speed increment.

Once the takeoff is reached, the hydrofoil gives enhanced performance, in terms of consumption and seakeeping, not possible to achieve by other types of vessels.

The particular structure of the craft requires a thorough study of the architecture of the hull, whose structure differs from others high speed vessels since the lift on wing surfaces are transmitted to the hull in limited areas (wing attacks).

Several experimental model tests, performed at the towing tank of the Krylov State Research Center (S.Petersburg, Russia), have allowed to better define the shapes of the hydrofoil and the profile of the wings.

Model tests have allowed us to evaluate the acceleration and the hydrodynamic behavior of the hydrofoil during the navigation. It includes resistance, propulsion, seakeeping in head and following seas, and directional stability.

Several numerical tests were conducted in the ANSYS Workbench environment. The analyzed model is complete with all the elements that characterize both the longitudinal and transversal strength.  The superstructure elements, the detail elements and the local reinforcement brackets connecting windows are excluded from the calculation.

The local toughness calculation of these interface structures will be discussed further with some load conditions that take into account the hydrodynamic loads that weigh directly on the wings.