Abstract: A system and method is provided for efficiently changing controlled engine speed of a marine internal combustion engine in a marine propulsion system for propelling a marine vessel. The system responds to the operator changing the operator-selected engine speed, from a first-selected engine speed to a second-selected engine speed, by predicting throttle position needed to provide the second-selected engine speed, and providing a feed forward signal moving the throttle to the predicted throttle position, without waiting for a slower responding PID controller and/or overshoot thereof, and concomitant instability or oscillation, and then uses the engine speed control system including any PID controller to maintain engine speed at the second-selected engine speed.

Abstract: This invention relates to the use of a venting assembly for conventional sails, comprising one or more aperture substantially perpendicular with the sail surface separating a fore and aft element of the sail. The aperture channels high energy air flow from the windward side of the sail through to the leeward side of the sail parallel to the sail surface, energizing the surface boundary layer and maintaining laminar air flow along the aft element of the sail.

Abstract: This invention relates to the use of a venting assembly for sails, comprising one or more aperture substantially perpendicular with the sail surface separating a fore and aft element of the sail. The aperture channels high energy air flow from the windward side of the sail through to the leeward side of the sail parallel to the sail surface, energizing the surface boundary layer and maintaining laminar air flow along the aft element of the sail.

Abstract: Embodiments of the present invention feature a device having aerodynamic lift surfaces that is capable of rotation about a stayed mast.

Abstract: A rigid foil sail having a full length vertical leading edge whose trim angle/angle of attack is controlled by the main sheet and trailing edge flaps attached rearwardly of the leading edge, each of which can be independently trimmed from a convenient deck level control tray to achieve easily adjustable camber. The design of the rigid foil sail allows depowering of the sail without altering mainsheet trim by decreasing the camber of the upper trailing flap thus also decreasing the heeling force created by the power of the upper trailing flap. Further, a void within the foil is filled with a lighter than air gas to assist in countering heeling moment to allow the boat to be driven without the loss of upwind pointing performance and without the loss of power and also allowing the boat to be driven to windward more efficiently with a minimum heel angle.

Abstract: A rigid foil sail having a full length vertical leading edge whose trim angle/angle of attack is controlled by the main sheet and at least two trailing edge flaps attached rearwardly of the leading edge, each of which can be independently trimmed from a convenient deck level control tray to achieve easily adjustable camber. The design of the rigid foil sail allows depowering of the sail without altering mainsheet trim by decreasing the camber of the upper trailing flap thus also decreasing the heeling force created by the power of the upper trailing flap. Such an arrangement allows the boat to be driven without the loss of upwind pointing performance and without the loss of power caused by luffing of the sail. Similarly, the boat can be better balanced by allowing the boat to be driven to windward more efficiently with a minimum heel angle.

Abstract: A fluid dynamic section provides one or more fixed size escapelets through a foil body to reduce the induced and interference drag caused by trailing vortices and similar wake turbulence. The escapelets, which can be provided in both aerodynamic and hydrodynamic structures, such as wings, tail sections; rotary blades, guy wire frames, wing sails, and various underwater keels and wing keels. The escapelets transfer energy from an inlet located in the high-pressure surface of the foil or foil body to an outlet located in the lower-pressure surface, allowing energy that would normally form a vortex at the tip of the foil to be redirected and dissipated in a beneficial way. As a result, drag is reduced and fuel economy is increased, while at the same time increasing the authority of ailerons and similar flight control surfaces, allowing aircraft that were not previously spin recovery rated to become spin recoverable.

Abstract: A steerable wing-type sail system for a wind powered craft. The system includes first and second secondary airfoils and that are spaced outwardly to the sides of the plane of the main wing, and that are positioned rearwardly of the trailing edge of the wing. The secondary airfoils are selectively pivotable so as to steer the main wing in one direction or the other. The main wing is also provided with a pivoting flap at its trailing edge, which pivots simultaneously with and in the same direction as the secondary airfoils. The secondary airfoils are carried on elongate horizontal booms mounted near the mid-span height of the main wing. The secondary airfoils pivot about vertical axes at the distal ends of the booms, and are operated by control cables that are retracted and paid out by linear actuators or similar mechanisms. The craft may be multi-hull vessel, such as a catamaran.

Abstract: An aerodynamic lift enhancing gate valve assembly comprising an airfoil blade disposed at a leading edge of a sail, forming a gate between the trailing edge of the airfoil blade and the leading edge of the sail. The airfoil blade captures wind and redirects it over the cambered surface of the sail to enhance the aerodynamic lift of the sail. The pressure of the wind captured by the airfoil blade is regulated by springs or elastic bands. In operation, the chord of the airfoil blade remains substantially parallel to the chord of the sail.

Abstract: A sailing craft propelled by a tilting sail system comprising an aerofoil sail capable of omni-directional attitude for wind propulsion. The sail is fixed to the craft in such a manner as to permit omni-directional attitude. Sail control means allows the sail placement in a forward propulsion attitude relative to wind direction. The sail is rigid and has an asymmetric shape.

Abstract: A steerable wing-type sail system for a wind powered craft. The system includes first and second secondary airfoils and that are spaced outwardly to the sides of the plane of the main wing, and that are positioned rearwardly of the trailing edge of the wing. The secondary airfoils are selectively pivotable so as to steer the main wing in one direction or the other. The main wing is also provided with a pivoting flap at its trailing edge, which pivots simultaneously with and in the same direction as the secondary airfoils. The secondary airfoils are carried on elongate horizontal booms mounted near the mid-span height of the main wing. The secondary airfoils pivot about vertical axes at the distal ends of the booms, and are operated by control cables that are retracted and paid out by linear actuators or similar mechanisms. The craft may be multi-hull vessel, such as a catamaran.

Abstract: A method and apparatus for increasing sail efficiency is disclosed. The apparatus comprises a second sail, disposed in a second plane substantially perpendicular to the first plane, wherein the second sail is disposed proximate a periphery of the first sail.

Abstract: A mastless sail for use in a two-seat kayak is disclosed. The apparatus is designed with a boomstick feature for supporting and controlling the bottom of the sail. The existing kayak paddles support and control the top of the sail. The apparatus is also designed for fast assembly and disassembly. No alterations to the kayak are necessary.

Abstract: The invention relates to a boat sail comprising a first (4) and a second (6) sheet, having similar shape and dimensions, coupled each other in correspondence of the outer perimeter and by a plurality of transverse ribs (12), provided between said sheets (4, 6), suitable to divide said sail into multi-sections (11), said sail (2) being characterised in that it provides a valve (14), that can be opened and closed to allow the air to enter within said sail into the space between said first (4) and second (6) sheets, at least a retractor element (15) provided on each rib (12), that can take two positions, respectively for the closure of the rib (12) and for opening the same, in order to make the sail taking a wing contour shape, and means (16) for opening and closing said retractors.

Abstract: In an improved sail for a sailboat, the trailing edges of a pair of serrated flaps of sailcloth are attached to the trailing edge of the sail, one on each side; the leading portions of corresponding members making up the serrated flaps are not fixed to the sail, but are connected to one another by short sections of line extending through holes in the sail. When the boat is tacked from one tack to the other, the leading portions of the members on the new windward side are pulled away from the surface of the sail by the wind, so that a serrated flow-impeding lip is provided on the windward side of the leech. At the same time, the lines pull the leeward members against the main body of the sail, so that drag is not increased substantially. Substantial improvements in sailing performance are realized, while no control action is required to cause the flaps to be suitably reconfigured upon tacking, and while ordinary sailing manuevers and all normal sail handling operations may be carried out without complication.

Abstract: In an improved sail for a sailboat, the trailing edges of a pair of serrated flaps of sailcloth are attached to the trailing edge of the sail, one on each side; the leading portions of corresponding members making up the serrated flaps are not fixed to the sail, but are connected to one another by short sections of line extending through holes in the sail. When the boat is tacked from one tack to the other, the leading portions of the members on the new windward side are pulled away from the surface of the sail by the wind, so that a serrated flow-impeding lip is provided on the windward side of the leech. At the same time, the lines pull the leeward members against the main body of the sail, so that drag is not increased substantially. Substantial improvements in sailing performance are realized, while no control action is required to cause the flaps to be suitably reconfigured upon tacking, and while ordinary sailing manuevers and all normal sail handling operations may be carried out without complication.

Abstract: A sail envelope has an internal mast or spar and one or more profiles (1) that is or are free to rotate relative to the longitudinal axis of the mast. Each profile has an outer edge in the form of a symmetrical aerofoil upon which the inner sides of the external sail surfaces bear.