A sail-propulsion element comprises a mast (3), an inflatable sail (1) consisting essentially of two substantially fluidtight adjacent surfaces (4a, 4b) joined together along their periphery, thus forming between them at least one cavity closed around the mast (3), at least one air conduit positioned between the inside and the outside of the cavity, at least one means for injecting air into said cavity, the sail once inflated having a profile that remains permanently symmetrical, irrespective of the movement of said propulsion element, or of the direction or strength of the wind, a headboard, and a sail. The sail comprises a plurality of cells (5) in the direction of the span of the sail, each cell (5) extending from the leading edge (6) to the trailing edge (7), said cells (5) being spaced apart by ribs made of a first soft material.

A sail propulsion element comprises a mast (3), an inflatable or non-inflatable sail (1) consisting essentially of two substantially fluidtight adjacent surfaces (5) joined together along their periphery, thus forming at least one closed cavity between them, an air conduit positioned between the inside and the outside of the cavity, at least one means for injecting air into the cavity, the sail once inflated having a profile that remains permanently symmetrical, irrespective of the movement of the propulsion element, or of the direction or strength of the wind, a headboard (10), and a sail receptacle (11). The mast is located forward of the center of aerodynamic thrust of the sail, the mast is or is not free to rotate by 360?, and the sail comprises at least one means maintaining a slight pressure in the sail.

A vehicle with total or partial sail propulsion comprises a hull (j), at least one sail, inflatable or not, at least one self-supporting mast (l) having a vertical axis, the mast comprising a fixed part (o) disposed at hull level and a movable part (p) that can move about the vertical axis. This vehicle is characterized in that the mast (l) comprises, in the fixed part (o), sensors for measuring physical parameters intended to supply digital data on the thrust force, the drift force, and the differential pressure of the sail, or else, in the movable part (p), sensors for measuring physical parameters intended to supply digital data on the aerodynamic thrust force projected in the axis of the sail, the aerodynamic thrust force projected in the axis at right angles to the sail, and the differential pressure of the sail.

An automatic wing control mechanism for sailing vessels is described. The automatic wing control mechanism adjusts a wing orientation with respect to the apparent wind to optimize its efficiency.

Various embodiments of a submerged submersible sailing vessel are disclosed. Such a submerged sailing vessel may comprise a submersible hull assembly, a keel coupled to and extending upwards from hull assembly towards a water surface, and a wind-catching assembly coupled to and extending upwards into the air from the keel for propelling the submerged sailing vessel. The hull assembly and the keel are submerged below the water surface as the vessel is propelled by the wind-catching assembly above the water surface.

Various embodiments of a submerged sailing vessel are disclosed. Such a submerged sailing vessel may comprise a submersible hull assembly, a keel coupled to and extending upwards from hull assembly towards a water surface, and a wind-catching assembly coupled to and extending upwards into the air from the keel for propelling the submerged sailing vessel. The hull assembly and keel are submerged below the water surface as the vessel is propelled by the wind-catching assembly above the water surface.

The invention relates to a system for the production of hydrogen from sea water. Said system comprises a ship (1) provided with sails (2) for capturing wind in order to move the ship, at least one turbine (3) which is disposed underneath the ship in order to remain submerged in the water and which is made to rotate by the action of the water flowing via same when the ship (1) moves in relation to the water, an electric generator (4) adapted to convert the rotation of the turbines (3) into electrical energy, a system (5) for generating hydrogen from the electrical energy generated, and hydrogen storage means (6). The sails (2) have a profile that can be configured between a folded non-operative position and an unfolded operative position, wherein they determine the profile of the rail and therefore the aerodynamic surface for contacting with the wind.

The invention relates to an inflatable rig for wind-powered sports equipment and a sailing rig set comprising such rigs.

The invention relates to a sail having a variable profile. The sail can vary between a folded non-operative position and an unfolded operative position, wherein they determine the profile of the sail (2) and therefore the aerodynamic surface for contacting with the wind, characterised in that the sail comprises at least one sail element (24) which is inflatable and stiffenable, and which can be actuated by inflation (30) and stiffening means (29), between a folded position corresponding to said folded non-operative position and said unfolded operative position, in which the sail (2) is inflated. The profile of the sail is divided into sections (21, 22) on both sides of a shaft (20), and comprises a support structure (23) on which said inflatable sail elements (24) are disposed, said inflatable sail elements being formed by inflatable pockets (24) which can be actuated by said inflation (30) and stiffening means (29).