Abstract: A surf-riding board or sailing board comprises two flexible side portions having a stabilizing effect upon the board in difficult water conditions and during maneuvering.

Abstract: The invention relates to a rig for a windsurfing board in which the clew (8) of the sail (2) prior to tensioning and trimming of the sail (2) is fixed in location in a stern fitting (10) of the wishbone boom (3). The stationary fixing can either be done preprogrammed with the aid of a scale, whereupon the wishbone boom (3) is fixed to the mast in that it is pushed downwardly from above and engaged, or a fixed point is established which holds the clew (8). In this embodiment the trimming of the said (2) is made in the bow fitting (11) in that the connection (15) between the mast (1) and wishbone boom (3) is constructed in such a manner that the mast (1) is displaceable longitudinally to and fro with respect to the wishbone boom (3) and lockable.

Abstract: The forked or wishbone boom or spreader gaff has two individual booms. Each boom has two sections which are telescopically fitted into each other. An arresting device is provided to lock the two respective boom sections in an adjustable position. Accordingly, the length of a given forked boom is adjustable to the cut of various sails of sailboards.

Abstract: The present invention is with respect to craft such as surfboards and more specially sailboards made up of a board body of synthetic resin foam and with a synthetic resin shell and having fittings such as a daggerboard case, mast foot sleeves or sockets, connection points for foot straps, skegs etc. The sailboard is made up of a base element having all the fittings on it. The top part of a skin-compatible, flexible light-weight synthetic resin or plastic is fixed on the base element. All mechanical forces are taken up by the base element while the greater part of the buoyant volume is formed by the top part. The top part may more specially be so designed that it may be taken off the base element and an other one put in its place.

Abstract: The present invention relates to an apparatus for the stabilizing of the direction of travel of watercraft. The invention relates specifically to a sword or fin for sailboards. In order to allow the wind-profile like shape of the apparatus to adjust itself in accordance with a prevailing velocity of flow or a prevailing flow thereagainst, the apparatus comprises two deformable side walls which are mounted to a rigid and stiff center wall exclusively at an area located at the leading edge thereof in relation to the direction of flow. These side walls enclose together with the two oppositely arranged surfaces of the center wall two void spaces. Depending on the prevailing pressure situations between the luff side and the leeward side, an optimal hydrodynamic flow profile is automatically generated. According to preferred embodiments, the trailing edge of the apparatus comprises vacuum pumps which communicate with the void spaces, which vacuum pumps are present in form of water jet pumps.

Abstract: A mast foot for sail boards having a universal joint for connection of the mast through the mast foot, with the sail board hull. The universal joint is joined up by way of a middle pin forming part of a bearing unit, which is designed to be fixedly joined to the hull. The middle pin is furthermore able to be moved, together with the universal joint, in relation to the rest of the bearing unit against the force of a spring in a direction generally normal to the deck of the sail board. The spring may be adjusted with respect to the force produced by it acting against upward motion of the middle pin. The bearing unit can be joined with the sail board hull in a sleeve by way of a turning joint like a bayonet connection.

Abstract: A windsurfing board with a hull, a mast and a wishbone or other spar for winging out the sail has side fin plates with lower stabilizing faces and an adjustment system for steplessly changing the level of such fin plates, or only producing two positions of adjustment so that such fin plates are under or clear of the water. The lower position under the water is designed for producing better planing properties of the windsurfer while the top position is used for sailing under only a light wind.

Abstract: A sailboard having an unstayed rig comprises a mast mounted by a universal joint on a surfboard having a retractable keel. A sail having a neck and a lower bolt-rope is attached between the mast and nocks of spars fixed to the mast for the retention and adjustment of the mast and sail. The lower bolt-rope of the sail extends from the nocks of the spars to the mast at a downward inclination, the spars being fixed to the mast above the neck of the sail. The surfboard is provided with a coupling portion for coupling to a similar surfboard by a coupling member to form a composite surfer.