WO1992007755A1

WO1992007755A1 - Maneuvering apparatus and method for sailing vessel

Info

Publication number: WO1992007755A1
Application number: PCT/US1991/007868
Authority: WO
Inventors: Ralph R. Johnson
Original assignee: Johnson Ralph R
Priority date: 1990-10-29
Filing date: 1991-10-25
Publication date: 1992-05-14
Also published as: AU8958891A

Abstract

A sailing vessel (10, 26 and 28) has an underside (14) with a pair of angular planar lift surfaces (30 and 32) for bringing the vessel (10, 26 and 28) to a planing mode and providing pitch stability, while under way. The vessel (10, 26 and 28) further has a pair of controllable boards (56 and 58), one for each lift surface (30 and 32), for providing lateral resistance to drift. Manipulation of these boards (56 and 58) in the same direction permits lateral movement of the vessel (10, 26 and 28) without changing its heading in order to provide rapid adjustment to heeling and righting imbalances, thereby permitting larger sail (28) areas. Lateral movement also can be used to keep the hull (10) pointing at a slightly higher angle into the wind than its actual direction of motion, thus utilizing the sides (16 and 18) of the vessel (10, 26 and 28) as additional sail area. The control mechanism (70, 72, 74, 76, 78, 80, 82, 84, 86, 88, 90 and 92) for the boards (56 and 58) includes a handle (94) which is rotated to change the heading of the vessel (10, 26 and 28) and/or moved inboard or outboard to laterally adjust the vessel (10, 26 and 28).

Description

MANEUVERING APPARATUS AND METHOD FOR SAILING VESSEL

This invention relates to sailing vessels and more particularly to such sailing vessels with a planing hull and an improved maneuvering system and method therefore.

Sailing vessels are among the oldest known form of transportation. These vessels convert wind energy into mo¬ tion of the vessel in well known manners. All sailing ves¬ sels include a hull which supports the vessel with buoyancy while at rest. When in motion, two different types of hulls can support the vessel and these are the displacement hull and the planing hull. For sailing vessels, the two types of hulls differ in how they support the vessel while under way. Displacement hulls continue to support the vessel with buoyancy whiie under way. Displacement hulls are partially submerged, and thus, push water aside to make headway. The forward resistance associated with displacing the water in¬ creases at a faster rate than the vessel's speed. This dis¬ placement hull characteristic presents significant speed limitations.

A planing hull, on the other hand, supports the vessel with dynamic lift, while under way. This enables it to, essentially, ride on top of the water. The lesser re¬ sistance associated with a planing hull, can remain con¬ stant, or even decrease as vessel speed increases. A com¬ bination of the above factors, make planing hulls more con- ducive to sailing at higher speeds.

In the past, displacement hulls far outnumbered planing hulls in sailing vessels. Concepts to increase their speed center around two fundamental approaches. One approach is to increase the vessel's sail area. This basi- cally increases its horsepower. The other approach is to make the hull narrower, relative, to its length, in order to reduces its forward resistance through the water. By using these two approaches, the faster displacement type vessels are generally the larger ones. As these vessels increase in size, their adjustments to correct leaning, or heeling, be¬ come more sluggish<. Without a quick correction to compen- sate for wind gusts and waves, these large displacement ves¬ sels have to use smaller than optimum sail areas to prevent capsizing, thereby sacrificing speed.

In recent years, interest in sailboat speed and per- formance has risen dramatically. The advent of the sail- board and many new sailboats with planing hulls is one re¬ sult of the new interest. Planing hulls generally have much less weight, with the crew being the only ballast providing the righting force. Both, less weight and dynamic lift, reduce forward resistance for these hulls. Minimizing for¬ ward resistance is one of the direct ways to enhance a ves¬ sel's speed capabilities. However, planing hulls, hereto¬ fore, have used lift surfaces, which span from bow to stern. Their primary function is to lift the vessel to a planing mode in order to escape the significant resistance associated with displacement hulls. However, once on plane, the planing hull vessel has no way of maintaining the opti¬ mum angle of impact with the water for efficient lift. The result is excessive wetted surface area and it's related resistance.

Another direct way to enhance a vessel's speed is to maximize the conversion of wind energy into forward driv¬ ing force. This is what sails are designed to do. It would seem then, any vessel with a planing hull could go faster with only two changes. It would need to add sail area and lengthen the lever arm of the righting force. This would convert more wind energy into driving force and offset the additional heeling loads. Theoretically, this process could continue to be repeated, with the vessel going ever faster. However, fluctuations in wind and water continually upset the balance between the vessel's heeling and righting forc¬ es, thereby limiting the speed.

With present sailing vessels, only a small part of the wind and water fluctuations are compensatable by ad- justments in vessel control. The remainder of these fluc¬ tuations still must be handled by reducing the sail areas. If vessels could handle larger fluctuations with control adjustments, sail areas, and hence speed, could be in- creased. However, vessel control, and its indirect rela¬ tionship to speed, is not easy to perceive, quantify or mea¬ sure. It affects both the vessel's driving force and for¬ ward resistance. A vessel's control ability is limited al- most entirely by it's response time to heeling adjust¬ ments. Vessels, up to now, have had no control adjustment to alter the righting loads.

In the past, three basic adjustments have been used to alter heeling forces and their corresponding reactions are as follows:

1. Turning the vessel into the wind. While being turned, the initial effect will be to heel the ves¬ sel even further. This is caused by the center of the vessel's forward momentum being higher than the center of its lateral resistance. Turning the ves¬ sel into the wind is similar to turning a bicycle opposite to the direction in which it is leaning. After the turn is completed, however, the vessel will heel less because the sail is more in line with the wind and, consequently, is hit by less wind.

2. Turning the vessel away from the wind. Essen¬ tially, the inverse of the above will hold true. During the turn, the vessel's forward momentum will tend to lessen the heel. After the turn, the ves¬ sel will heel more because the sail, being more across the wind, will be hit by more wind.

3. Adjusting the sail to be more in line with, or across, the wind. With this adjustment, the vessel will heel less or more, respectively.

The lateral component of the wind force makes a vessel want to drift sideways and existing sailing vessels utilize one or more submerged surfaces to provide resis¬ tance to sideways drift. Essentially, the job of the sub- merged surface is to maintain the vessel traveling in the direction it is pointed. This surface can be a keel, cen- terboard, dagger board or the hull itself. While the sub¬ merged surface can take the form of many shapes, its center of lateral resistance is located approximately halfway be¬ tween the bow and stern. The orientation of the submerged surface is generally fixed fore and aft, parallel to the longitudinal axis of the vessel. This orientation provides resistance to any movement other than forwards or back¬ wards. Unfortunately, as a result, this submerged surface precludes any lateral movement, or sideslipping, of the hull, even when it becomes desirable and advantageous. Al¬ so, as a result, the submerged surface necessarily acts as a very inefficient fulcrum, about which the vessel must turn, with great resistance, when being maneuvered.

All types of sailing vessels also utilize a rudder to steer the vessel. The rudder is usually located in the stern, some distance from the vessel's center of lateral resistance or turning fulcrum. Unlike the submerged sur¬ faces which provide the vessel's lateral resistance to drift, the rudder is controllable and carries no lateral load while sailing straight. When rotated, it creates a lateral load of its own. This moves the stern of the ves- sel laterally, while the midsection resists, thus turning the vessel. The time it takes to turn a vessel, or adjust the sails to alter the heeling load, is the response time of that adjustment. The above mentioned control adjust¬ ments, on vessels up to now, have had relatively slow re- sponse times. This greatly limits the amount of sail area which can be employed. Therefore, this control response time is the limiting factor in sailing speed today.

Another disadvantage to turning the vessel relative to the wind is that, either during or after the turn, the opposite effect of that which is desired is produced be¬ cause of the change in forward momentum, or effective sail area. Compounding this dilemma, is the fact that, heeling force, generated by a momentum change, increases as the vessel is turned faster. This severely limits the type of high speed situations in which one can make quick adjust¬ ments, and thus, further limits the speed of the vessel. A disadvantage to adjusting the sails relative to the wind is that the control lines to the sails become highly loaded. The sails must, therefore, be rigged with a high degree of mechanical advantage in order to allow one to adjust the loaded sails with relatively little effort. To accomplish this, one must take in, or let out, large amounts of control line and this is usually the slowest and least chosen of the various possible heeling adjustments. This problem with adjusting the sails, of course, is com- pounded on vessels with many sails.

The submerged surfaces which resist lateral drift on vessels heretofore have another limitation in that they provide no fore and aft adjustment of the vessel's center of lateral resistance. Further, prior art sailing vessels have only had limited adjustment in their center of effort, which is created by the sail. Therefore, these centers virtually never coincide, thereby creating a constant ten¬ dency to turn the vessel. If a vessel's tendency is to turn toward the wind, it is said to have a weather helm; if its tendency is to turn away from the wind, it is said to have a lee helm. This tendency must be counteracted with the rudder, thereby creating additional resistance. Thus, ves¬ sels up to now, virtually always sail somewhat inefficient¬ ly, often with considerable forward resistance. in the past, people have suggested vessels with steering devices utilizing a plurality of controllable, submerged surfaces. For example, see U.S. patent number 367,771 to J.C. Witmer, granted August 2, 1887 and enti¬ tled, "Combined Steering Device and Brake For Vessel", U.S. Patent 1,780,767 to fl. Scott- Paine, granted November 4, 1930 and entitled "Means For Steering Water Craft", U.S. Patent Number 3,223,065 to A.B. Wilson, granted December 14, 1965 and entitled "Sailboat" and U.S. Patent Number 4,082,053 to W.R. Woodward, granted April 4, 1978 and enti- tied "Multirudder Steering System For Multihull Boats".

In each of these patents, there is shown a design which in¬ corporates a plurality of rudders located generally fore and aft on the vessel. These rudders are connected to turn in opposite directions in order to assist the vessel in turning better. However, none of these prior art patents permit the rudders to be turned towards the same side of the vessel at the same time, and thus none suggests permit- ting lateral movement, or sideslipping, of the vessel.

There have also been other attempts at improving the performance of the keel in a sailing vessel, generally involving modifications of the hydrodynamic shape of the keel to enable it to better resist the lateral component of the wind's force. For example, see United States Patent Number 3,080,845, E.G. Pollak, granted March 12, 1963 and entitled "Boat Having Movable Keel Device" and United States Patent Number 4,193,366 to R.K. Salminen granted March 18, 1980 and entitled, "Sailing Boat and Method Of Operating The Same". The Pollak patent discloses a rotat¬ ing flap at the trailing edge of the keel and the Salminen patent discloses a pair of rotating wingettes beneath the keel. While possibly increasing a vessel's resistance to lateral drift, these designs maintain a vast majority of the keel surface fixed in a fore and aft orientation and again, precludes any sideslipping of the hull.

Sailing vessel development, over the years, has been greatly hindered, ironically enough, by its own tradi¬ tion. Unlike any other racing sport, sailing has given little significance to overall unrestricted speed. In¬ stead, great emphasis has been placed on structured "class" racing. These classes generally define and/or limit such things as length, width, weight, sail area, surfaces for lateral resistance to drift, number of crew, and the like. Therefore, the vast majority of sailing vessel design ef¬ fort has been focussed on refining designs within an exist¬ ing set of parameters. If sailing speeds are to continue increasing with any significance, new, less direct ap¬ proaches, holding larger advances, must be sought out. In accordance with one aspect of this invention, there is provided a sailing vessel having at least one hull having a bow end and a stern end and means for controlling forward movement of said vessel. The invention is charac- terized by a plurality of boards extending from said hull, each having a surface area of which at least fifty percent is rotationally operated together in the same angular di¬ rection to control movement of said vessel, one of said boards being positioned towards said bow end of said vessel relative to another one of said boards. The invention ad¬ ditionally is characterized by means for lifting said hull upon forward movement of said vessel.

One preferred embodiment of the subject invention is hereafter described, with specific reference being made to the following drawings, in which:

Figure 1 is a perspective view, partially cut-away, of a sailing vessel utilizing the subject invention;

Figure 2 is a cross-sectional view taken across lines 2-2 of the sailing vessel shown in Figure 1, with mast and sails omitted;

Figure 3 is a more detailed and exploded view of the sleeve and board installation;

Figures 4A and 4B illustrate one type of movement of the steering device and the corresponding movement of the sailing vessel;

Figures 5A and 5B illustrate another type of move¬ ment of the steering device and the corresponding movement of the sailing vessel; Figures 6A, 6B and 6C illustrate yet another type of movement of the steering device and the corresponding movement of the sailing vessel;

Figure 7 is a plan view of a sailing vessel with a constant turning moment due to offset centers of effort and lateral resistant;

Figure 8 illustrates a sailing vessel with one type of sail configuration and the appropriate board depth place¬ ments to align the centers of effort and lateral resis¬ tance; Figure 9 illustrates the same sailing vessel shown in Figure 8 with another type of sail configuration and the appropriate board depth placements to align the centers of effort and lateral resistance; Figures 10A and 10B are schematic plan views illus¬ trating load diagrams for two sailing vessels moving in the same direction, but being pointed in different directions. Referring now to Figures 1 and 2, a sailing vessel 10 containing a steering device 12 and improved planing surfaces on a bottom 14 of the subject invention is shown. Except for bottom 14, vessel 10 is shaped much like conven¬ tional sailing vessels of the prior art and includes a port side 16, starboard side 18, bow end 20 and stern end 22 (shown as partially cut-away in Figure 1), which together with bottom 14, form a hull 24, or other type of body or frame. Secured within hull 24 is a conventional mast 26 having affixed thereto one or more conventional sails 28, both of which are shown in Figure 1 partially cut-away in order to better view the more critical parts of the inven¬ tive subject matter. It should be understood that vessel 10, mast 26 and sails 28 may differ greatly from the gener¬ alized representation thereof shown in Figure 1, depending upon the type and function of the vessel. Bottom 14 of vessel 10, in the preferred embodi¬ ment, is a planing type bottom having aft lift surface 30 and fore lift surface 32. Lift surfaces 30 and 32 can best be seen in Figure 2 and both are flat and span the entire width of vessel 10. In addition, lift surfaces 30 and 32 are both angled slightly upward in a direction towards bow end 20, at an angle generally between 2 and 7 degrees above the horizontal. In addition, fore lift surface 32 curves upward and narrows at bow end 20 to a virtual point. The aft end of fore lift surface 32 terminates at an edge 34 and the aft end of aft lift surface 30 terminates at stern end 22 as an edge 36. Both of edges 34 and 36 are gener¬ ally straight and generally perpendicular to the longitudi¬ nal axis of vessel 10.

Referring additionally to Figure 3, within hull 24, two hollow cylinders 38 and 40 are formed with an opening

41 thereof entirely through bottom 14. Cylinders 38 and 40 are positioned along the longitudinal center line of vessel 10, just forward of edges 36 and 34 respectively. Openings 41 of cylinders 38 and 40 are formed to be perpendicular to lift surfaces 30 and 32 and their lower end is flush with respective lift surface 30 and 32. The upper end of each of cylinders 38 and 40 is stepped upward into hull 24 by a sufficient amount to be above the water line and thereby avoid leakage into hull 24. Both cylinders 38 and 40 have a ledge 42 (best seen in Figures 2 and 3) formed at the top of the opening thereof and sized to receive and hold a sleeve 44 or 46, when installed with a retaining ring 48, so as to permit easy rotation. Retaining ring 48 may be flat, with a small break and may have a hole through each end. The thickness of ring 48 is slightly smaller than the width of a groove 49, located above ledge 42 and into which ring 48 fits to maintain sleeves 44 and 46 in place within cylinders 38 and 40. Ring 48 has a slight opening therein and a pair of holes to receive a pliers type tool and ring 48 may be installed by reducing the opening and thereafter releasing it.

The bottom of hull 24 also includes a generally vertical circular opening 50. Opening 50 is located along the longitudinal centerline of vessel 10, just forward of the aft cylinder 38. Opening 50 has an inside diameter large enough and long enough so a tiller 52 can be held therein, while still being rotated as hereafter explained. Both sleeves 44 and 46 are housed inside aft and forward cylinders 38 and 40, respectively, as best seen in Figure 3. The outer surface of each sleeve 44 and 46 is cy¬ lindrical with a small lip 54 of a slightly larger diameter at the top thereof. The outside diameter of sleeves 44 and 46 and lip 54 and the inside diameter of opening 41 and ledge 42 are such that sleeves 44 and 46 rotatably fit in- side opening 41 and are held in place by lip 54 resting on ledge 42 after ring 48 has been inserted. The lower end of each sleeve 44 and 46 is a flat surface and the length of each sleeve 44 and 46 is such that the bottom thereof, when inserted in cylinders 38 and 40, is flush with lift sur¬ faces 30 and 32. The diameter of each sleeve 44 and 46 is large enough to permit a board 56 or 58 to slide in an opening 60 or 62 therein. In some regard, boards 56 and 58 are similar to conventional rudders used on sailing vessels. Openings 60 and 62 may be offset slightly aft in sleeves 44 and 46, respectively. The end within hull 24 of each of sleeves 44 and 46 contains a cam lever 64 and 66, respectively, as an integral part thereof. Cam levers 64 and 66 remain free to rotate and are located just forward of sleeve openings 60 and 62. Cam levers 64 and 66 are oriented such that the lever portion faces forward. Cam levers 64 and 66 each con¬ sists of one circular end with a straight flat surface tan¬ gent thereto. It has a hole through the circular end, slightly offset towards the straight surface, with the hole being just large enough to fit loosely over a small rod, made integral with each sleeve 44 and 46. Formed as such, the lever portion of cam levers 64 and 66 may be rotated up to permit boards 56 or 58 to be inserted through openings 60 or 62 and down to lock boards 56 or 58 in position. Boards 56 and 58 are partially housed by sleeves 44 and 46. They each protrude out of both ends of sleeves 44 and 46 and have a symmetrical airfoil type cross section, such as the NACA 63 series. NACA is an acronym meaning Na¬ tional Advisory Committee for Aeronautics, whose organiza- tional functions have been transferred to the National Aero¬ nautics and Space Administration. This cross section is constant over the upper end and tapers in size, while main¬ taining proportions, at the lower distal end relative to vessel 10. Boards 56 and 58 also have an elongated hole 68 through the upper end to permit easy handling.

The upper end of forward sleeve 46 has an arm 70 as an integral part thereof oriented towards port side 16 and the upper end of aft sleeve 44 has a tiller 72 as an inte¬ gral part thereof. Both tiller 52, which fits in opening 50 as previously described, and tiller 72 have a tubular cross section, are generally vertical at their lower end and bend forward between 60 and 90 degrees. Tiller 72 has a hole through its distal end and a pin 74 rotatably connects a tiller extension 78 thereto. Similarly, tiller 52 has a hole through its distal end and a pin 76 rotatably connects a tiller extension 80 thereto. In addition, tiller 52 has an arm 82 as an integral part thereof extending from it's lower end. Arm 82 extends towards port side 16, perpendicu¬ lar to the tiller's plane of bend.

Both arms 70 and 82 are flat with a hole through their port facing end to accept pins 86 and 84, respec¬ tively. The hole in each arm 70 and 82 may be the same distance from its respective center of rotation. Link 88 is straight with a tubular cross section and has a clevis shape at each end with a hole therethrough to accept pins 84 and 86 and thereby connect link 88 with arms 82 and 70. Tiller extensions 78 and 80 are straight with a tubular cross section. Each tiller extension 78 and 80 has a hole at each end to accept pins 74, 76 90 and 92. Pins 74 and 76 rotatably connect the inboard end of tiller extensions 78 and 80 to tillers 72 and 52, and pins 90 and 92 rotat¬ ably connect the outboard end of tiller extensions 78 and 80 to handle 94. Handle 94 is straight with a tubular cross section and a hole at each end to accept pins 90 and 92. Pins 74, 76, 84, 86, 90 and 92 may be cylindrical, with a head at one end and an integral spring clip for re¬ tention at the other end. The manner of using sailing vessel 10 and steering device 12 is similar to those in present use. To turn a prior art sailing vessel, one pushes or pulls the rudder tiller laterally in the direction opposite to the desired turn. To maneuver sailing vessel 10 using steering device 12, one simulates the desired maneuver of vessel 10 with handle 94. If one desires vessel 10 to be turned toward or away from the wind, handle 94 is turned (rotated) toward or away from the wind respectively. For example, if one de¬ sires to turn vessel 10, this may be accomplished by turn- ing either or both of boards 56 or 58. In Figures 4A and 4B, only rear board.58 is rotated, which causes vessel 10 to change directions by rotating about front board 56 much like any prior art vessel rotates about the keel when the rudder is changed. Changing the direction of vessel 10 shown in Figure 4B is accomplished by rotating handle 94 about pin 92 so as to be aligned with the direction of the desired turn. In the situation shown in Figure 4A, stern 22 actually changes direction in the water, as indicated by arrow 100.

Alternatively, as seen from Figures 5A and 5B, the direction of vessel 10 may also be changed by rotating only forward board 56, so that vessel 10 rotates about board 58, whereby bow 20 changes direction in the water, as indicated by arrow 102 in Figure 5B. Rotating board 58 is accom¬ plished by rotating handle 94 about pin 90, as seen in Fig¬ ure 5A, so that handle 94 is aligned with the direction of the desired turn. The difference between the turn of ves- sel 10 manifested by Figures 4B and 5B is similar to the difference between front wheel and back wheel steering of a motor vehicle. Both types of steering have certain advan¬ tages under certain conditions and vessel 10 permits a sailor to choose the most advantageous turn. Referring to Figures 6A, 6B and 6C, if one desires vessel 10 to slip laterally downwind or upwind, without changing the direction vessel 10 faces, handle 94 is pushed or pulled, downwind or upwind, without being ro¬ tated. Specifically, when vessel 10 is heeling, as seen by the dashed lines in Figure 6C, speed is being lost. To re¬ coup the lost speed, it is desirable to right vessel 10 to a position shown by the solid lines in Figure 6C, that is to move the lateral center of hull 24 beneath mast 26. Righting may be accomplished by pushing or pulling handle 94 in the direction of desired slippage of hull 24, as seen in Figure 6A, which causes equal rotation of boards 56 and 58 and slippage of hull 24 from the dashed line posi¬ tion to the solid line position as seen in Figure 6B, and as indicated by arrow 104. This lateral slipping ability provides vessel 10 with an adjustment to heeling, that has a much faster re¬ sponse than any prior controls available with conventional sailing vessels. It does so by combining a change in both heeling and righting loads together. If vessel 10 is heel¬ ing too much, it can be slipped laterally downwind, thereby causing sail 26 to move more with the wind. The result is less heeling load due to the wind having less impact on sail 26. Slipping vessel 10 laterally downwind also in¬ creases the righting load. This can be attributed to the fact that the center of lateral load (boards 56 and 58) of vessel 10 is below its center of mass. As boards 56 and 58 create a lateral load, to change the vessel's direction of motion, the tendency of the mass of vessel 10 is to con¬ tinue straight. This results in a rolling force which also lessens the angle of heel of vessel 10. If vessel 10 is heeling too little, it can be slipped laterally upwind to create the inverse effect. If any combination of turning and lateral slipping is desired, one merely simulates the maneuver with handle 94. It should be noted that handle 94 and tiller extensions 78 and 80 can be swung to allow con¬ trol from either side of vessel 10.

At rest, hull 24 of vessel 10 provides lift in the same manner as any sailing vessel hulls in present use, that is by the buoyancy. While under way, however, vessel 10 achieves a planing mode, as do some sailing vessels in present use. However, bottom 14 of vessel 10 differs by how it minimizes forward resistance while planing. It also differs by how it enables steering device 12 to adjust the angle of heel of vessel 10. While under way, dynamic lift is produced by each of lift surfaces 30 and 32 of vessel 10, particularly at the aft end of each. By separating and concentrating the vertical support into these two fore and aft areas, pitch stability is greatly enhanced. This as¬ sures a more constant lift surface angle impacting the wa¬ ter and, in turn, provides optimum lift efficiency at all times.

Stability and efficiency can be further increased with larger distances separating the areas of vertical sup¬ port during planing. As the speed of vessel 10 increases, the areas of support become more concentrated and the weight of vessel 10 rides on a smaller area of the lift surfaces 30 and 32. The areas of bottom 14 which must re¬ main in contract with the water, regardless of speed, is the aft portion of the two lift surfaces 30 and 32. Thus, the aft portion of lift surfaces 30 and 32 become the ideal location for boards 56 and 58, since boards 56 and 58 be¬ come the only submerged controllable surfaces of vessel 10 at high speed.

While planing, the areas of bottom 14, other than the active aft portion of lift surfaces 30 and 32, do not ride in the water. This minimizes wetted surface and the related forward resistance at all times. As vessel speed increases, less lift surface area is required to support vessel 10 and accordingly, vessel 10 rises in the water. This, in turn, reduces the active area of lift surfaces 30 and 32 being contacted by water and further minimizes re¬ sistance. As vessel 10 rises in the water, the shape of the active portion of lift surfaces 30 and 32 which remains in contact with the water also changes, in that its aspect ratio (width divided by length) increases, thereby further elevating lift efficiency. As bottom 14 of vessel 10 planes on top of the water, boards 56 and 58 then provide the only surfaces to resist or create lateral movement of vessel 10. Lift surfaces 30 and 32 are designed to produce ef¬ ficient dynamic lift. The angle of inclination may be de- termined by the width, length and weight of vessel 10. In addition, edges 34 and 36 should be relatively sharp, so as to provide an abrupt separation, as the water leaves lift surfaces 32 and 30, respectively, in order to minimize the contact of that water with surfaces that do not produce dy- namic lift, again minimizing resistance.

As previously described, cylinders 38 and 40 pro¬ vide a housing within which sleeves 44 and 46 rotate. Sleeves 44 and 46, in turn, provide a partial housing for boards 56 and 58, such that boards 56 and 58 can slide up or down therein until locked in place by operation of cam levers 64 and 66. This provides independent forward and/or aft adjustment of the amount of submerged surface presented by boards 56 and 58. Boards 56 and 58 provide vessel 10 with a controllable method of resisting lateral drift, and when manipulated, also create lateral loads to change the direction of motion of vessel 10, thereby directly effect¬ ing the angle of heel of vessel 10 by altering both the heeling and righting loads together, resulting in a fast re¬ sponse time, relative to prior art vessels. Thus, signifi¬ cantly larger sail areas may be used and higher speeds at¬ tained.

Boards 56 and 58 can greatly enhance the heeling adjustment of vessel 10 with as little as half (50%) of their effective surface area being controllable. If less than one half of the surface area of the boards 56 and 58 is controllable, the boards 56 and 58 would then act as a conventional keel and maintain the direction of the vessel generally in the forward direction. An example of such a keel is shown by the aforementioned Pollak U.S. patent 3,080,845. Boards 56 and 58 are much more efficient and effective if at least three quarters (75%) of the effective surface area is controllable, whereas the optimum in both efficiency and effectiveness would be obtained when all

(100%) of the effective surface area is controllable. The fore and aft location of boards 56 and 58 within sleeves 44 and 46 determines the load on the controls.

The greater the submerged surface area of boards 56 and 58, the greater the lateral resistance provided there¬ by. Thus, the amount boards 56 and 58 are submerged below lift surfaces 30 and 32 is made adjustable and the amount of surface area, and accordingly the total lateral load produced by each board 56 and 58, is variable. In this way, the fore and aft location of the center of lateral resis¬ tance can be adjusted to coincide with the center of effort of vessel 10. Referring to Figures 7, 8 and 9, the center of effort is designated by the letter A and is generally in the sail area of vessel 10. For a single sail vessel, as shown in Figure 8, the center of effort A is more towards the stern than would be the case with a double sail vessel, as seen in Figure 9. The center of lateral resistance is designated by the letter B and generally is determined by the lateral drag presented by a keel on a conventional sailboat or by both boards 56 and 58 on vessel 10. If, as seen in Figure 7, the center of effort A and the center of lateral resistance B are misaligned, vessel 10 will tend to rotate and will require an adjustment of the rudder in a conventional sailboat to compensate for the nonalignment. This in turn increases the forward resistance, and has a negative impact on performance.

As seen from Figures 8 and 9, the depth of each of boards 56 and 58 may be selected to move the center of lat¬ eral resistance B in a fore or aft direction to be verti¬ cally aligned with the center of effort A. This assures optimum efficiency regardless of conditions or sail selec¬ tion. This adjustment also allows boards 56 and 58 to be less submerged when sailing at high speed and thereby mini¬ mizes resistance and again enhances overall performance. At lower speeds, when the heading of vessel 10 becomes a larg¬ er factor, boards 56 and 58 may be submerged to a greater extent to enable vessel 10 to sail a closer heading into the wind, again enhancing overall performance.

Steering device 12 is arranged so that handle 94 simulates the desired maneuver of vessel 10. Handle 94 may be operated with a single hand and any lateral movement, by the forward, aft or both ends of handle 94 results in a similar movement by bow end 20, stern end 22, or both, of vessel 10, respectively. This makes learning to sail ves¬ sel 10 quick and easy.

Thus, one can appreciate that sailing vessel 10, including steering device 12, provides lateral movement, or sideslipping, without changing the heading of vessel 10.

This efficient method of maneuvering vessel 10 allows one to adjust the angle of heel much faster and at higher speeds than could be done with prior art sailing vessels. Further, it can all be done with only one hand. The abil- ity to sideslip the hull of a heeling vessel, laterally, back underneath the sail, delivers the desired adjustment in the most direct manner and with the least effort. The responsive nature of vessel 10, as permitted by steering device 12, enables a sailor to maintain control over heel¬ ing, with much larger sail areas and at much higher speeds. The ability to independently steer bow end 20 and/or stern end 22 of vessel 10 to either side, or oppo- site sides, in similar or varying degrees, simultaneously or separately, forwards or backwards, contributes to the maneuverability of vessel 10 around docks and other ves¬ sels.

To maneuver sailing vessel 10 with steering device 12, one merely maneuvers handle 94 in the same manner as the desired maneuver for vessel 10. If one desires vessel 10 to be turned more toward or away from the wind, handle 94 is rotated toward or away from the wind accordingly. If one desires that vessel 10 slip laterally downwind or up- wind without turning, handle 94 is simply pushed or pulled downwind or upwind, without being rotated. Any combination of turning and lateral slipping of vessel 10 can be accom¬ plished by merely moving handle 94 in a similar manner. This natural maneuver simulation with handle 94, makes the control system of this invention quick and easy to learn, for even the newest of beginners.

If desired, vessel 10 can be continuously sailed at a slight angle, pointing higher into the wind than its ac¬ tual direction of motion. This increases the forward drive of vessel 10 and reduces its tendency for lateral drift from the wind hitting its longitudinal surfaces. This fea¬ ture essentially converts the sides of any part on vessel 10, including the hull itself, into additional, but less effective, sail area. This can best be seen in Figures 10A and 10B, where "E" represents the direction of vessel mo¬ tion and "F" represents the direction of the wind. In Fig¬ ure 10A, vessel 10 is moving in the same direction it is pointed and in Figure 10B, vessel 10 is pointing at a slightly higher angle into the wind than its direction of motion. In both Figures 10A and 10B, the sail 28 is at the same angle with respect to the wind vector "F". The benefits of vessel 10 in each of the Figure 10A and Figure 10B situations is graphically seen in the load vector diagrams. In these diagrams, "G" represents the load vector resulting from the wind acting on sails 28 and is further broken down into "Gl" and "G2", its lateral and forward components, respectively and "H" represents the load vector resulting from the wind acting on the longitu¬ dinal surfaces of vessel 10 and is also broken down into "HI" and "H2", its lateral and forward components, respec- tively. Vector "I" combines "Gl" and "Hi" to represent the vessel's total lateral load. Vector "J" combines "G2" and "H2" to represent the total forward load of vessel 10. As can be seen, the forward load vector is greater and the to¬ tal lateral load vector is less in Figure 10B, thereby in- dicating the advantage of sailing higher into the wind.* Further, this invention can easily be used as the main and/or auxiliary hull or hulls on any type or form of sailing vessel, such as monohulls, catamarans, proas, tri¬ marans, sailboards and the like. It is easy to see that, with the only submerged parts being independently adjust¬ able in depth, this invention carries minimal resistance through the water at all times. This adjustment also al¬ lows the center of lateral resistance to coincide fore and aft with the center of effort, thereby increasing perfor- mance. It is also easy to see that since the only wetted surfaces on bottom 14 are, essentially, the active portion of lift surfaces 30 and 32, which continually get smaller as speed increases,.this invention carries minimal resis¬ tance on top of the water at all times. And with the more responsive control system, as described herein, which al¬ lows the use of larger sail areas, it's easy to see that this invention is not only easy to learn and use, but is capable of delivering much higher speeds to beginners and experienced sailors alike. While my above description contains many specifici¬ ties, these should not be construed as limitations on the scope of the invention, but rather as an exemplification of one preferred embodiment thereof. Many other variations are possible. For example, a vessel can have more than one aspect of this invention, possibly interconnected, as in the case of multihull type vessels. Additionally, the ves¬ sel may be of displacement or planing type. Further, a ves- sel may have any number of lift surfaces, which can vary in size, shape, angle and location or may have any number of boards or submerged control surfaces, which can also vary in size, shape, angle and location. In addition, boards 56 and 58 can be made adjustable or fixed, in depth of submer- sion and steering system 12, which manipulates the sub¬ merged control surfaces, may be of any method, operated by one or more hands, and may employ mechanical linkages, such as tillers or wheels, or may utilize electronics, hydrau¬ lics, pneumatics or other drives. Furthermore, intermediate boards positioned between boards 56 and 58 may be included and connected with steer¬ ing device 12 to provide more responsive control. For ex¬ ample, if three boards are used, the middle board may be controlled by steering device 12 to rotate to an angle pro- portionally between the angles of the fore and aft boards 56 and 58.

Accordingly, the scope of this invention should be determined not by the embodiment illustrated, but by the appended claims and their legal equivalents.

Claims

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A sailing vessel (10, 26, 28) having at least one hull (10) having a bow end (20) and a stern end (22) and means (26, 28) for controlling forward movement of said vessel (10, 26, 18) characterized by a plurality of boards (56 and 58) extending from said hull (10), each having a surface area of which at least fifty percent is rotation- ally operated together in the same angular direction to control movement of said vessel (10), one (58) of said boards (56 and 58) being positioned towards said bow end (20) of said vessel (10, 26, 28) relative to another one (56) of said boards (56 and 58) and means (30 and 32) for lifting said hull (20) upon forward movement of said vessel (10, 26, 28).

2. The vessel according to claim 1 wherein said hull has a bottom (14) further characterized in that said bottom (14) includes a plurality of generally planar sections (30 and 32) positioned along a line from said bow (20) end to said stern end (22), each bottom section (30 and 32) being at an upward angle towards said bow end (20) so as to pro¬ vide lift when said vessel (10, 26, 28) is moving.

3. The invention according to claim 2 characterized in that at least one of said boards (56 or 58) extends from said hull (10) to an adjustable depth.

4. The invention according to claim 2 or 3 character¬ ized in that each of said boards (56 and 58) is positioned from the stern (22) facing side of one of said bottom sec¬ tions (30 and 32) .

5. The invention according to claim 4 characterized in that said boards (56 and 58) are positioned along the lon¬ gitudinal center line of said vessel (10, 26, 28).

6. The invention according to claim 1 characterized in that at least one of said boards (56 or 58) extends from said hull (10) to an adjustable depth.

7. The invention according to claim 1, 2 or 6 charac¬ terized in that said boards (56 and 58) are positioned along the longitudinal center line of said vessel (10, 26, 28).

8. The invention according to claim 1, 2 or 6 charac¬ terized in that said vessel (10, 26, 28) further includes means (12) for operating said boards (56 and 58) together and in the same angular direction.

9. The invention according to claim 8 characterized in that said means for operating (12) is operable to set the angle of each of said boards (56 and 58).

10. The invention according to claim 8 characterized in that said angle of each of said boards (56 and 58) is set differently.

11. The invention according to claim 8 characterized in that said means for operating (12) includes a manually op¬ erable mechanism (70, 72, 74, 76, 78, 80, 82, 84, 86, 88, 90 and 92) which is moved unidirectionally to adjust the

5 angular direction of said boards (56 and 58) identically and simultaneously, and rotationally to adjust the angular direction of said boards (56 and 58) differently.

12. A method of operating a planing sailing vessel (10, 26 and 28) having a plurality of longitudinally spaced boards (56 and 58) which operate together and in the same direction characterized by the step of rotating said boards

» (56 and 58) together while said vessel (10, 26 and 28) is planing to slide said vessel (10, 26 and 28) to one side by an amount sufficient to maintain a desired angle of heel.

13. The method according to claim 12 wherein said sail¬ ing vessel (10, 26 and 28) has means (26 and 28) for con¬ verting wind energy to motion characterized in that said step of rotating is in a direction to slide said vessel (10, 26 and 28) to be under said converting means (26 and 28).

14. The method according to claim 12 or 13 further characterized by the step of rotating said boards (56 and 58) by different angular amounts to adjust the heading of said vessel (10, 26 and 28) and rotating said boards (56 and 58) by the same angular amount to slide said vessel

(10, 26 and 28) to be under said converting means (26 and 28).