US3763810A

US3763810A - High speed boat with planing hull

Info

Publication number: US3763810A
Application number: US00237852A
Authority: US
Inventors: P Payne
Original assignee: Blade Hulls Inc
Current assignee: Blade Hulls Inc
Priority date: 1972-03-24
Filing date: 1972-03-24
Publication date: 1973-10-09
Anticipated expiration: 1990-10-09

Abstract

A boat capable of cutting through rough waves at high speed with astonishing stability has a hull provided with a flat planing surface which in plan is the shape of a thin wedge or delta. The sides of the boat rise upwardly and outwardly with a simple concave curvature from the two edges leading from a knife edge bow at the point of the wedge. The slender wedge shape moving through the water at high speeds develops continuous spray sheets up its sides which are intercepted by the outwardly curving portions of the hull sides. Spray rails or deflectors may also be utilized to intercept the spray sheet, such deflectors being inclined at a small angle to the bottom of the planing surface. The knife edge bow rises upwardly and forwardly with a concave curvature from the point of the wedge and eventually terminates in a forwardly sloped bow transom. A keel skeg minimizes side slipping. A stern transom, which rises substantially perpendicular to the trailing edge of the delta or wedge may have a rearwardly extending bustle secured thereto for buoyancy and roll stability at low speeds.

Description

Primary Examiner-Milton Buchler Assistant ExaminerCharles E. Frankfort Attorney-Richard C. Sughrue et a1.

. I v United States Patent [191 [111 3,763,810

Payne Oct. 9, 1973 HIGH SPEED BOAT WITH PLANING HULL 7 5 Inventor: Peter R. Payne, Silver Spring, Md. [57] I ABSTRACT l AL8jli 212991 1 111 I R YH Q, M A boat capable of cutting through rough waves at high 22 Filed: Mar. 24 1972 speed with astonishing stability a provided with a flat planing surface which in plan is the shape 1 1 pp 237,852 of a thin wedge or delta. The sides of the boat rise up- Rehted Application Data wardly and outwardly with a simple concave curvature from the two edges leading from a knife edge bow at [63] fgy g sx gtg of the point of the wedge. The slender wedge shape moving through the water at high speeds develops continuous spray sheets up its sides which are intercepted by E 81. the outwardly curving portions of the hull sides. p y 58] Fieid R 66 5 F rails or deflectors may also be utilized to intercept the 114/66 5 5 spray sheet, such deflectors being inclined at a small angle to the bottom of the planing surface. The knife edge bow rises upwardly and forwardly with a concave [56] Cited curvature from the point of the wedge and eventually UNlTED STATES PATENTS terminates in a forwardly sloped bow transom. A keel 3,661,109 5/1972 Weiland 114/665 R k g minimizes side slipping. A stern transom, which 2,980,924 4/1961 Canazzi l14/66.5 R rises substantially perpendicular to the ili edge of 5 g f g the delta or wedge may have a rearwardly extending 3469549 951969 is l14/66'5 R bustle secured thereto for buoyancy and roll stability at low speeds.

21 Claims, 21 Drawing Figures PATENTEU [JCT 91975 SHEE 2 U 6 PATENTEU 3,763,810

sum nor 6 Y 1 HIGH SPEED BOAT WITH PLANING HULL RELATED APPLICATIONS This application is a continuation-in-part of my prior application Ser. No. 167,737 filed July 30, l97l, now abandoned in favor of this application.

BACKGROUND OF THE INVENTION l. Field of the Invention The present invention is directed to a high speed boat which does not slam or pound waves but cuts through them to ride smoothly at high speed even in rough seas.

advantages and it was found that certain hull shapes,

characterized by open" water line planforms'at the stern experience -a net positivepressure when underway, so that the hull lifts out of the water with a consequent reduction in wetted area. The reduction in wetted area, and the more favorable flow around that part of the boat still in the water, permits a planing craft to be accelerated'through the region of high pressure drag caused by wave making, provided the boat has sufficient power. On calm water, a planing hull is very efficient and speeds approaching 100 mph. are normal for quantity produced sport boats and speeds in the order of 200 m.p.h. are achieved by racing hydroplanes. Unfortunately, water is rarely smooth, and in waves such boats are subject to pounding which is physiologically intolerable and can also break up the hull strucutre. Thus, although it is both efficient and simple, the planing craft is not able to operate at high speed 'in waves. I

Because there is a great need for water craft capable of high speeds, many alternative vehicle concepts have been developed in attempts to evade the problem of pounding. Some of these prior art developments-are the surface'piercing hydrofoils, fully submerged hydrofoils, air cushion vehicles, captured air bubble craft, super critical displacement hulls and submarines. It would be inappropriate to analyze the characteristics of each of these vehicles here, but it should be noted that only submarines and fully submerged hydrofoils have clearly circumvented the pounding problem while all are much more complicated than a planing'boat. This added complexity manifests itself in greatly increased first cost, decreased reliability and severe operation limitations of one kind or another.

The planing craft only planes on a small portion of it -Others have utilized the "deep V" in hull design in order to reduce pounding. Although it is generally supposed that a deep V somehow cushions the impact, it actually reduces the efficiency of the lifting surface and hence, in effect, constitutes a reduction of the planing surface size for a given boat size. Unfortunately, the deep V not only does not reduce the wetted area, but actually increases it thereby leading to higher skin friction drag. v

Hydrofoils raise the hull of the boat up out of the water so that high speeds can be obtained but the hydrofoil is limited in rough sea' operations by the distance the hull is raised out of the water. Thus, with waves above a certain size, the boat will be subjected to the same severe pounding that ordinary planing craft are subjected to. I

SUMMARY OF THE INVENTION The present invention provides a high speed boat with a planing hull which is not subjected to pounding in waves but cuts through the waves, thereby giving the boat an amazingly steady level ride. The boat is not .only efficient at high speed but has excellent seaworthiness at low speed due to its low natural frequencies in roll, and pitch. At high speed, the boat is stabilized by spray sheets thrown up that contact the hull sides.

The boat is simple and rugged in construction. Preferably, all of the exterior surfaces of the boat are either planar or provided with a simple curvature as opposed to other high speed boats all which include compound curvatures, thus increasing cost and complexity.

The boat of the invention is provided with a unique bow configuration which allows the, boat to knife through most waves, thereby reducing the pounding effect, however with extremely large waves, the lift characteristic of the inclined bow transom enables the boat to ride over such waves.

The boat of this invention is provided with deltashaped or thin wedge-shaped planing surface with the sides of the boat extending upwardly and outwardly with a concave curvature from the leading edges of the delta or wedge. Such a configuration substantially reduces the wetted area giving a reduction in skin friction. It also produces continuous spray sheets from the sides which contact the outwardly curving sides to provide both stabilization and lift. The delta-shaped bottom is normally submerged so that passage through a wave does not result in an increase in lifting area. The delta-shaped configuration of the deck results in the aerodynamic center being located well aft to provide a boatwhich is almost impossible to flip." The concave curvature of the sides of the boat, allows the boat to bank into far tighter turns than was ever possible with prior art boats. The same concave curvature of the sides also leads to a relatively dry cockpit in rough weather since the spray thrown upwardly is directed outwardly and downwardly rather than upwardly as is customary with boats having a convex hull configuration. These spray sheets add to stability in turns. Deflector rails may be placed on the sides of the hull to inte'rcept the continuous spray sheets, a keeel skeg may be used on the bottom of the hull to minimize side slip, and trim tabs or other means may be utilized to counteract propeller torque. While a single wedge shaped hull is desired in most cases for a powered craft, a number of separate but connected slim wedge shaped hulls are useful in other vessels, e. g., a sailing trimaran with one wedge forward and two wedges aft.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation of the boat according to the present invention.

FIG. 2 is a bottom plan view of the boat shown in FIG. 1.

FIG. 3 is a stern view of the boat shown in FIG. 1.

FIG. 4 is a schematic front view of the boat shown in FIG. 1, illustrating the configuration of the bow transom and the progressive cross sectional configuration of the boat at selected points from the bow toward the stern.

FIG. 5 is a longitudinal partial cross sectional view of a modified boat construction having the overall external configuration similar to that shown in FIG. 1.

FIG. 6 is a longitudinal partial sectional view of the stern section of the modified boat construction.

FIG. 7 is a cross sectional view taken along the line 77 of FIG. 5.

FIG. 8 is a sectional view taken along the line 8-8 of FIG. 5.

FIG. 9 is a cross sectional view taken along the line 99 of FIG. 6.

FIG. 10 is'a side elevation of a modification showing a plurality of deflectors or spray rails on the side of the hull.

FIG. 11 is a detailed sectional view taken along line llll of FIG. 10 showing a spray rail in section.

FIGS. 12, 13 and 14 are bottom plan, side elevation and sectional elevation views respectively of a modification of this invention in the form of a sailing trimaran.

FIGS. 15, 16 and 17 are side elevation and sectional views (2) respectively of a modification of this invention in the form of a sea plane.

FIGS. I8, 19 and 20 are side elevation and two sectional views of a'modification of this invention in the form of a larger boat, e.g., a large passenger ferry.

FIG. 21 is a graph of the lift drag ratio plotted against the lift coefficient for various trim angles.

DETAILED DESCRIPTION OF THE INVENTION A powered boat 10 having high speed planing capability in rough seas, is provided with a delta-shaped planing surface 12 with the apex 14 disposed adjacent the bow and the base line 16 disposed adjacent the stem. The delta or thin wedge shaped planing surface need not be formed of straight sides as good results are also obtained if the long sides of the delta or wedge are slightly convex or concave. The bottom of the planing surface also need not be perfectly flat but may vary to some concavity. v

The bow of the boat immediately adjacent the plan-. ing surface is formed as a concave knife edge 18 which extends upwardly and forwardly from the planing surface 12 and terminates in a bow transom 20 which is flat and angled at approximately 45 relative to the planing surface 12. The sharper the knife edge, the less spray will be thrown up at this edge.

The sides of the boat 22 and 24 extend upwardly and outwardly from the edges or chines 26 and 28 respectively of the long sides of the delta-shaped planing surface 12. The concave configuration of the sides 22 and 24 is conveniently a simple curvature and the sides terminate at the upper edge in

gunwales

30 and 32. As an example of a simple curvature a cubic curve can be used. Such a cubic curve could be y a a, z a,

' z where y is a lateral dimension, z'is height above the planing surface and a a1 and a are constants. A spray rail 33 is along each gunwale. A transom 34 extends upwardly relative to the planing surface 12 and is joined thereto along the base line 16 of the delta-shaped configuration.

A bustle 36 may be secured to the transom 34 to provide additional roll stability, especially at lower speeds, when the boat is not planing.

Sides

38 and 40 of the bustle have a slightly different curvature than the sides of the boat but could be a continuous extension of the sides 22 and 24 of the boat. The bustle 36 is provided with a channel 42 extending from the boat transom 34 to the bustle transom 44 to provide the necessary clearance for the drive train between the engine 35 inside the boat and the propeller 37. On opposite sides of the channel the bottom of the bustle has two

angular surfaces

46 and 48 which are stepped relative to the planing surface 12 so they are not in contact with the water while the boat is planing. The

gunwales

50 and 52 of the bustle are shown in a stepped manner relative to the

gunwales

30 and 32 on the main hull but the gunwales on the bustle could be a straight continuation of the gunwales on the boat hull.

The decking and interior configuration of the boat may vary considerably. In the embodiment shown in FIGS. 1 4 inclusive, the decking 54 is provided with a convex curvature between the gunwales and is continuous relative to the boat per se and the bustle. The forward portion of the decking 54 extends outwardly over the blunt bow transom 20 a short distance and functions as a spray deflector. That is, when the blunt bow transom 20 strikes a wave and causes spray, the spray will not fly back into the passengers face as it will be deflected by deflector 55. This deflector will also incidentally provide some lift from this spray deflection. A forward cockpit S6 is provided for the driver with a suitable wind screen 58. An aft cockpit 60 is provided for the passengers and rearwardly of the passengers, is the engine hatch 62 which is flush with the decking 54 in the closed position. In the preferred embodiment, the plan configuration of the decking will be deltashaped similar to the planing surface but of greater area thereby locating the aerodynamic center well aft to prevent flipping of the boat at high speeds.

FIG. 4 clearly shows the flat bow transom 20 and the various cross sectional configurations A, B, C and D taken along the lines AA, B-B, C-C and D-D respectively in FIG. 1. FIG. 4 also shows the concave curvature of the sides 22 and 24 as they rise from the progressively widening delta-shaped planing hull 12.

The boat hull, according to the present invention, may be constructed from any suitable material such as plywood, fiberglass or metal and the size of the boat may vary considerably from a small runabout to a large ocean line type vessel since the principles of construction are valid for all sizes. By utilizing the concave sides having only a simple curvature, it is extremely economical and easy to construct the boat. In view of the wave cutting characteristics of the boat in rough water, it is unnecessary to provide an extremely heavy, strong internal frame, since pounding is minimal.

FIGS. 5 9 inclusive showa specific embodiment of the boat wherein a metalic skin, such as aluminum, is used for the hull. The boat shown in FIGS. 5 9 is substantially identical in configuration to the boat shown in FIGS. 1 4 and differs only in detailed construction v features which are primarily internal of the boat. The only superficial difference is best shown in FIGS. 6 and 9 and involves only the shape of the tunnel in the bustle which provides the necessary clearance for the drive train. In this embodiment, the tunnel is curved to facilitate the construction using metal sheets as opposed to the rectangular tunnel shown in FIGS. 1 4.

FIGS shows two

internal bow plates

70 and 72. Each of the

bow plates

70 and 72 is provided with a concave curvature which extends upwardly and forwardly from the bottom of the boat which is defined by a deltashaped plate 74. The

bow plates

70 and 72 have flanged edges 76 and 78 for attaching the sides of the boat thereto. The bottom edge of the plate 70 has a flange 80 for securement to the plate 74 and the three edges of the delta-shaped plate 74 are bent downwardly to form similar attaching flanges 82. The bow plate 72 is substantially narrower throughout than the bow plate 70 as best shown in FIG. 7. The inner and outer side walls of the

hull

84 and 86 are secured to the

bow plates

70 and 72. The outer wall 86 stops at the bow plate 72 and separate knife edge component 89 is attached by fastenings 91 shown in FIG. 7.

The bow transom 90 extends upwardly from the bow plate 72 at substantially a 45 angle relative to the bottom 74 and has flanged edges 92. An inner bow transom 94 extends parallel to the bow transom 90 but extends only downwardly as far as the innermost bow plate 70 to which it is secured. Both bow

transoms

90 and 94 are secured to a deck plate 96 and the outer skin 86 of th'eboat along their flanged edges. In all instances the various members may be secured to each other by any suitable means, such as riveting or weld- The decking 100, FIGS.-7 and 8, is provided with a flange 102 for attachment to the upper edge of the i prevention means in the form of a keel skeg or fin keel on the bottom of the planing surface serves to minimize outer skin 86. The joint of flange 102 is encapsulated 'in rubber or the like 103 to form robust spray rails which also serves to protect the hull against impact, e. g., with the dock. The decking is provided with a step at 104 for receiving any internal cross structure such as I the'bow hatch, engine hatch, or the like so that these structural members will be flush with the decking The inner edge of the decking 100 is secured to the inner skin or waIl 84 of the hull. 1 I

In FIG. '6 the transom has an inner wall and an outer wall 1 12, which may be of integral one-piece construction joined by an upper cross member 114. The

bottom edges of the transom are separated by and secured to a crossbar 116 and the inner wall of the transom 110 is secured to the downwardly turned flange 82 of the bottom plate 74.

The bustle 120 has bottom and side member 122 with a semicircular curvature at 124 to define the tunnel which provides the necessary clearance for the drive train. The member 122 also has a flat bottom portion 126 which extends outwardly at a small angle relative to the horizontal and an upwardly and outwardly curved side portion 128 of a concave curvature which is a continuation of the curved sides of the boat. The bustle also has a cross member 130 with an upwardly and outwardly turned flange 132. A decking member 134 with a configuration similar to the decking member 100 is secured to the flange 132 and the edge of the side 128. A gunwale 136 is formed as a continuous line along the entire length of the boat and is encapsulated in a resilient material as described above. A bustle transom has an inner wall 140 and an outer wall 142, which extend upwardly at an angle parallel to the main boat transom.

As seen from the previous detailed discussion of the various components, a double walled boat hull is provided. The entire chamber defined by the dual wall structure may be filled with any suitable buoyant cellu- Iar material such as polystyrene foam or the like to provide buoyancy of flotation tanks. The various members of the boat hull are defined chambers of watertight construction. An epoxy concrete or other suitable material completely fills the depression'defined by the flanges 82 on the delta-shaped base plate 74. This epoxy concrete which has considerable weight per unit volume provides a sealing means for the various seams and also provides the correct degree of ballast necessary to provide the boat with roll stability when in a displacement mode. Numerous other materials may be used as ballast and separate sealing means may be used to seal the seams. Also, the ballast may be located,

above the delta-shaped planing surface within the boat.

As stated previously, the bustle is not an absolutely essential feature to the present boat construction but if used, does provide additional roll stability at low speeds. The voids in the bustle structure may also be filled with a foam material similar to that shown in FIGS. 5, 7 and 8.

In order to minimize-side slip when turning, the boat is provided .with suitable side slip prevention means such as a keel skeg 152 as shown in FIGS. 1 3 or a'fin keel 154 on the bottom of the planing surface as shown in FIG. 10.

When the boat is planing with the forefoot of its bow above the waterline, a turn can cause side slip. This side slip can cause the chine to drop and dig in resultingin unpleasant lateral deceleration. The use 'of side slip side slip.

is compensated by torque counteracting means which 5 in a preferred embodiment can be a simple trim tab 156 on one side of the aft end of the planing surface of the hull as shown in FIGS. 1 3. This trim tab could be adjustable, but this is not necessary. Moreover, other means of counteracting torque can be used to provide a rolling moment equal and opposite to the propeller torque moment. Additionally, such torque opposing means could incorporate the engine cooling water inlet in the trim tab. I

As an example of this invention, an 18 foot marine plywood boat built in'accordance with the principles disclosed above knifed through 3 and 4 foot waves of the Chesapeake Bay at speeds between 35 and 50 miles per hour with the boat carrying three people having approximate gross weight of 2,200 pounds. The power was transmitted to a cupped prop at approximately 4,400 r.p.m.by a Mercruiser 140 h. p. engine. On the straightaway and in turns the ride was exceptionally stable even when small craft warnings and high seas forced other boats to harbor. Boats built in 22 foot length with aluminum hulls have cleanly parted waves of 4 5 feet high and wave lengths of 20 40 feet at speeds near 50 miles per hour with no pounding as compared with the best of conventional hulls which have to drop speed to keep control. The boats have consistently crossed the Chesapeake Bay in winds of 20 40 knots and are outstandingly safe in rough weather at all speeds of operation. When the boat gets underway the hull lifts progressively and rapidly to move from a displacement mode to a planing mode. When initially accelerating, the bow raises but then trims in a few seconds to provide a smooth ride. The knife edge bow cuts through some waves and passes over some.

When underway, the planing bottom of the hull functions as a planing surface. Spray sheets spray up from each side edge of the hull aft of the knife edge bow and these aid in supporting and stabilizing the boat. Because the hull is super critical," i. e., it has a resonant frequency less than the frequency of encounter of waves, acceleration of the boat in rough seas makes the ride even smoother.

As shown in FIGS. 10 and 11 the side surfaces 22and 24 of the boat may be provided with a plurality of deflectors or

spray rails

158, 158'. and 158". These are to take advantage of the spray sheets and increase the lift to drag ratio. As a slender wedge such as the hull of this boat moves through the water at high speeds, spray sheets develop up and along the sides. The spray sheet will go upwardly and outwardly from the bow of the boat and from the side edges, and the spray angle may vary along the length of the hull. The water in the spray sheet has kinetic energy which is utilized as the spray sheet hits the curve of the hull; in other words, the spray'sheet momentum is reacted as a lift force on the boat by deflecting it back downward. While the outer curved surfaces of the sides 22 and 24 of the hull can and do accomplish this, an additional effect can be obtained by utilizing deflectors or inclined spray rails 158, 158' and 158" as shown in FIG. 10. The spray rails are inclined at an angle to the normal inclination of the boat while planing so that the pressure drag is partially offset by a forwardly acting component of the resulting force.

Summarizing, the boat of this invention utilizes a fully submerged planing surface with a thin wedge shape so that lift area is not increased when it passes through the wave, nor is the boat decelerated by a bluff bow shape. Propelling such a thin wedge shape through the water results in the development of lateral spray sheets, the momentum flux in which is comparable to the total lift on the bottom. The sides of the boat deflect these spray sheets outward, substantially recovering this momentum flux; or if desired, deflectors can be utilized to deflect the spray sheet outward and downward, thus recovering even more lift. If the boat banks, then the spray sheet on the low side becomes thicker and its additional momentum provides the necessary roll stiffness. The same is true in side slip, except that the spray sheet on the side to which it is slipping becomes thicker adding force to oppose the side slip. A most dramatic example of the power in these spray sheets is obtained when the boat is trimmed with the how very high, then jumped sideways drift off a wake. Upon reimpact with the water, it starts to trip in the direction of motion; at the same time the spray sheet rises up the side and pushes it back again. The resultant wiggle takes a very short space of time.

While the foregoing description is applied to a powered planing boat, the theory of operation and the shape of the hull are not so limited. For example, the invention can be applied to a sailing trimaran as shown in FIGS. 12, 13 and 14. In this case the hull 170 is formed of three

slim wedges

172, 174, 176 with the slim wedge 172 forward and the

other wedge sections

174, 176 aft. The bow configuration still includes the knife edge 178 and the outwardly flaring concave sides such as side 180; these sides flare outwardly of each of the wedge shaped sections, except for the inboard sides of the aft wedge sections. Trim tabs 182 may be used to trim the boat in pitch and roll, and flaring side deflectors 184 may also be provided. Of course, the boat has the conventional rudder 186 and control 188 and may have optional footwells 190 in each of the aftmost wedge sections. This embodiment of a trimaran could be powered.

FIGS. l5, l6 and 17 show application of the principles of this invention to the body of a flying boat, i. e., a seaplane. The plane fuselage 190 is constructed with the bottom in accordance with the principles of this invention including a thin wedge shaped planing surface 192 with a knife edge 194 at the bow thereof and outwardly curving sides 196. The plane may have retractable wing tip floats 198 and a retractable fairing 199.

The principles of operation of the FIGS. 12 l4 and FIGS. 15 17 embodiments are the same as the principles for the other described embodiments.

FIGS. 18 20 show a further embodiment of the invention as applied to a larger ship, in this case an 85 foot long passenger ferry. The principles of the invention are the same. That is, the boat has a thin wedge shaped planing bottom 200 with a sharp knife edge concave bow portion 202 and above it, a blunt inclined bow portion 204.

Concave sides

206 and 208 extend upwardly and outwardly from the sides of the bottom to

gunwales

210 and 212. In this case the bustle 214 is behind a step 216 at the end of the planing surface or wedge shaped bottom. A propeller drive 218 is below the planing surface, not behind it. Propeller shafts 220 are connected to the propellers from each of three

diesel engines

222, 224, 226. A keel skeg and fairing 228 are provided for each shaft and steering is by means of one or more rudders 230. The space above the gunwales can conveniently have rows of seats 230 for passengers with a control cabin 232 on top. This 85 foot long, 200 passenger ferry cruises at 40 knots and has ninety tons gross weight. It is powered by three 1450 horsepower diesels.

FIG. 21 is a plot of the lift drag ratio, an indication of the efficiency of the hull against the lift coefficient. The lift coefficient is a non-dimensional coefficient equal to the pressure supporting the boat over the dynamic pressure in the water. In the equation A equals the total weight, q equals the dynamic pressure of the water which in turn is one-half times p times v where 9 equals the mass density of water (about 2 slugs per cubic foot) and v equals the velocity of the boat in feet per second. 0 is the wedge angle (one-half the included angle of the apex of the wedge) and x is the length of the planing surface in feet. The trim angle is the angle of trim in the water. Both the trim angle and the wedge angle are expressed in radians. The wedge angle, the curve of the side and the height of the gunwales can vary depending upon the condition the boat is designed for. However, with the criteria applicant has disclosed, these choices would be apparent to skilled boat designers. As can be seen from FIG. 21 the preferred included angle of the wedge apex is between about IO' and 30 for most applications.

be concave or convex. Also the sides of the boat can curve inward near the planing surface before curving upwardly and outwardly.

What is claimed is:

l. A boat having a planing hull capable of operating with stability at high speeds in rough seas comprising:

a. a thin wedge shaped planing surface forming a bottom of the hull with the apex of the wedge at a bow portion of the hull,

b. a knife edge at a lower portion of the bow of the hull extending upwardly and forwardly of the apex of the wedge,

c. a forwardly inclined blunt bow transom forming the upper portion of the bow of the hull above the knife edge,

d. concave sides of the hull extending upwardly and outwardly along the sides of the wedge shaped planing surface and positioned to intercept spray sheets thrown up from sides of the planing hull to assist in stabilizing the boat.

2. A boat having a planing hull as in claim 1 wherein the knife edge is forwardly inclined in a concave manner and the blunt bow transom if flat.

3. A boat having a planing hull as in claim 1 wherein said concave sides are each defined by a smooth simple curve in only one direction and extend over the entire surface of the sides of the wedge.

4. A boat having a planing hull as in claim 1 further comprising turning side slip minimizing means secured to the bottom of the hull.

5. A boat having a planing hull as in claim 4 wherein the side slip minimizing means is a keel skeg along a longitudinal axis of the hull.

6. A boat having a planing hull as in claim 4 wherein the side slip minimizing means is a fin keel positioned on a longitudinal axis of the hull.

7. A boat having a planing hull as in claim 1 further comprising spray sheet deflector means attached to the concave sides of the hull.

8. A boat having a planing hull as in claim 7 wherein the spray sheet deflector means are inclined at an angle to the planing surface.

9. A boat having a planing hull as in claim 8 wherein the spray sheet deflector means comprise a plurality of separated spaced deflector sections.

10. A boat having a planing hull as in claim 1 further comprising propeller torque counteracting means on the hull.

11. A boat having a planing hull as in claim 10 wherein the propeller torque counteracting means is a trim tab attached to one side of the bottom rear of the planing surface.

12. A boat having a planing hull as in claim 1 wherein the included angle of the apex of the wedge shaped planing surface is between l0 and 30.

13. A boat having a planing hull as in'claim I wherein the boat is driven by motive power.

14. A boat as set forth in claim 13 further comprising a bustle portion secured to and extending aft of said stern transom, said bustle having a bottom surface stepped up relative to said planing surface, concave sides having a curvature similar to the curvature of the sides of the boat along said wedge-shaped planning surface and a central longitudinally extending notched portion in the bottom surface to provide clearance for a stern drive extending through the stern transom.

15. A boat having a planing hull as in claim 13 wherein the motive power is engine means carried by the hull driving propeller means under the planing surface.

16. A boat having a planing hull as in claim 1 wherein the boat is a flying boat and the hull is a portion of a fuselage.

17. A boat having a planing hull as in claim 1 wherein the boat is a trimaran with a hull as defined in front and a pair of spaced apart wedge shaped spaced apart hulls aft.v

18. A boat having a planing hull as in claim 17 wherein the aft hull sides are concave on their outer surfaces only.

19. A boat having a planing hull as in claim 1 further comprising a spray protector extending outward from the bow forwardly of the top portion of the blunt bow transom.

20. A boat as set forth in claim 1 wherein said wedge shaped planing surface is defined by a triangular sheet of material having integral flanges about the periphery which form a receptacle and further comprising ballast means disposed in said receptacle forming smooth bottom surface.

21. A boat as set forth in claim 1 having a deck which is wedge shaped similar to said planing surface but having a larger area.

Claims

1. A boat having a planing hull capable of operating with stability at high speeds in rough seas comprising: a. a thin wedge shaped planing surface forming a bottom of the hull with the apex of the wedge at a bow portion of the hull, b. a knife edge at a lower portion of the bow of the hull extending upwardly and forwardly of the apex of the wedge, c. a forwardly inclined blunt bow transom forming the upper portion of the bow of the hull above the knife edge, d. concave sides of the hull extending upwardly and outwardly along the sides of the wedge shaped planing surface and positioned to intercept spray sheets thrown up from sides of the planing hull to assist in stabilizing the boat.

12. A boat having a planing hull as in claim 1 wherein the included angle of the apex of the wedge shaped planing surface is between 10* and 30*.

13. A boat having a planing hull as in claim 1 wherein the boat is driven by motive power.

17. A boat having a planing hull as in claim 1 wherein the boat is a trimaran with a hull as defined in front and a pair of spaced apart wedge shaped spaced apart hulls aft.