A watercraft may include a crane for lifting loads. The crane may include a tower and a boom that is rotatble with respect to the tower. The tower may be positioned inside the outer contour of the watercraft so as to minimize the profile of the watercraft on radar. The watercraft may include a superstructure within which the tower may be disposed. The superstructure may include planar outer walls that are obtuse relative to a horizontal plane. A rotary bearing may be utilized to connect the boom to the tower and permit the boom to rotate relative to the tower. Further, when the boom is in a rest position, a lower edge of the boom may be positioned 10 cm or less above the crane deck.”

The present disclosure is directed generally toward sailing vessels. One example is a catamaran with one or more pivoting masts per hull member, which may pivot from a generally perpendicular upright position, to a generally flat stowed position toward the bow of the hulls. The masts are capable of sustaining a plurality of sails, which may travel 180 degrees with respect to the hulls.

The invention relates to a sailing rig system (SRS) for a sailing ship comprising one or more airfoil sails comprising one or more sail defining frames including at least three airfoil sail shape-defining edges and/or at least three airfoil sail shape-defining corners. The sail may be controllable, rotatable, pivotable, trimmable, reefable, stowable, slidable, windable, guidable, coaxial, weathervaning, wind/sun tracking, freestanding; it may provide cambering, reinforcing, sealing, boundary layer control, shielding means, sections and connections and it may be transparent. The frame may be a closable/deployable rotor sail frame. The frame may include rig components and the SRS may further comprise vertical/oblique/horizontal spars coupled with spar couplings. It may further comprise lateral, fore-and-aft, superposed sails, actuators, power generators, power sources, thermal management systems, defined rotor sails. It may provide sail twist. It may be coupled with a sailing ship with defined ship couplings. A sailing method is proposed.

The present disclosure is directed generally toward sailing vessels. One example is a catamaran with one or more pivoting masts per hull member, which may pivot from a generally perpendicular upright position, to a generally flat stowed position toward the bow of the hulls. The masts are capable of sustaining a plurality of sails, which may travel 180 degrees with respect to the hulls.

A propulsion system for a boat comprises a plurality of aerofoils connected to a main mast. At least one of the aerofoils is a displaceable aerofoil adapted to be displaced along the main mast between an open position and a closed position. When the displaceable aerofoil is in its open position the aerofoils together form a sail of open sail area. When the displaceable aerofoil is in its closed position at least some of the aerofoils overlap to form a sail of closed sail area, the closed sail area being less than the open sail area. The propulsion system can include a displacement mechanism to displace the displaceable aerofoil between its open and closed positions; at least one of the aerofoils having a solar panel thereon; and/or a stub mast extending along and free to rotate about a stub axis and connected to the main mast by a stub pivot.

The device disclosed herein is for a folding mast device for use on watercraft. In the preferred embodiment, the mast is used on a bridge erection boat; however, additional watercraft may also incorporate this device. The mast includes clamps and other components in order to allow the mast to be assembled and disassembled without tools, which also makes the assembly and disassembly quick. The mast is also quickly removable and replaceable. The mast also can incorporate safety features, such as lighting and other devices needed for safe navigation, and is capable of adjusting to accommodate fabrication differences.

A propulsion system for a boat comprises a plurality of aerofoils connected to a main mast. At least one of the aerofoils is a displaceable aerofoil adapted to be displaced along the main mast between an open position and a closed position. When the displaceable aerofoil is in its open position the aerofoils together form a sail of open sail area. When the displaceable aerofoil is in its closed position at least some of the aerofoils overlap to form a sail of closed sail area, the closed sail area being less than the open sail area. The propulsion system can include a displacement mechanism to displace the displaceable aerofoil between its open and closed positions; at least one of the aerofoils having a solar panel thereon; and/or a stub mast extending along and free to rotate about a stub axis and; connected to the main mast by a stub pivot.

A watercraft incorporating a wind propulsion system, revealing a main mast and an auxiliary mast. According to the invention, provision is made for a length of the auxiliary mast between a flexible joint and the deck as well as an included angle from the main mast and deck capable of being locked in position on variable lines.

The device disclosed herein is for a folding mast device for use on watercraft. In the preferred embodiment, the mast is used on a bridge erection boat; however, additional watercraft may also incorporate this device. The mast includes clamps and other components in order to allow the mast to be assembled and disassembled without tools, which also makes the assembly and disassembly quick. The mast is also quickly removable and replaceable. The mast also can incorporate safety features, such as lighting and other devices needed for safe navigation, and is capable of adjusting to accommodate fabrication differences.

Embodiments of the present invention are directed to a passive, automatic wing-control mechanism for sailing vessels. A cam is attached to one end of a rotatable mast as part of a rotatable wing, and a tensioner is configured to exert a constant force perpendicularly against the cam. When a wing is in a no-go sailing angle with respect to an apparent wind, the cam does not exert a torque on the mast. When the wing is outside the no-go sailing angle, the cam exerts a counter-torque to a torque caused by the apparent wind acting on the rotatable wing, causing the wing to remain at a predetermined angle with respect to the apparent wind.