Abstract: This invention relates to a variable trim trimaran in which side floats (2) are provided that are connected to the central hull (1) by means of devices (3, 5) that allow them to shift vertically, wherein a deck structure (4) is provided that is connected to the central hull (1) and is so shaped as to cover at the top portion said side floats (2), so that they come to belong in the general outline of the trimaran itself.

Abstract: The invention refers to a variable geometry hydrofoil boat, equipped for this purpose with secant foils supported by articulated arms operated automatically or manually. The invention makes it possible to obtain a craft which, depending on operational requirements, may function either in the "totally submerged foil" mode or in the "secant foil" mode, that is to say with a variable foil surface. The secant foils supported by arms articulated to the hull may, in a variant of the embodiment, also be applied to fast-moving and streamlined naval units of the semi-planing type, for the purpose of damping their rolling and pitching movements.