US3330239A

US3330239A - Boat hull with tunneled v-bottom

Info

Publication number: US3330239A
Application number: US394253A
Authority: US
Inventors: Henry J Dornak
Original assignee: Individual
Current assignee: Individual
Priority date: 1964-09-03
Filing date: 1964-09-03
Publication date: 1967-07-11
Anticipated expiration: 1984-07-11

Description

H- J. DORNAK July 11, 1967 BOAT HULL WITH TUNNELED V-BOTTOM 4 Sheets-Sheav 1 Filed Sept.

Henry J. Dornalr INVENTOR.

July 11, 1967 Filed Sept. 3, 1964 H. L DCDRFJAP BOAT HULL WITH TUNNELED V-BOTTOM Fig. 3

4 Sheets-Sheet 2 Henry J Oornak IN VENTOR.

J ly 1957 H. J. DORNAK 3,330,239

BOAT HULL WITH TUNNELED V-BOTTOM Filed Sept. 5, 1964 4 Sheets-Sheet 5 Henry J Darna/r INVENTOR.

M4052 BY m, vm

July 11, 1967 H. J. DORNAK 3,330,239

BOAT HULL WITH TUNNELED V-BOTTOM Filed Sept. 5, 1964 4 Sheets-Sheet 4 Henry .1. Dorna/r 1 N VEN TOR.

United States Patent 3,330,239 BOAT HULL WITH TUNNELED V-BOTTGM Henry J. Dornak, 601 S. Mechanic St., El Campo, Tex. 77437 Filed Sept. 3, 1964, Ser. No. 394,253 21 Claims. (Cl. 114-56) This invention relates to a novel and useful boat hull of the type including a forward upwardly and forwardly curving bow portion and a substantially longitudinally straight planing portion. The planing portion of the bottom of the boat hull of the instant invention defines a longitudinal centerline and at least one pair of downwardly opening generally inverted V-shaped and longitudinally straight lift tunnels which extend along opposite sides of the longitudinal centerline of the bottom. Each of the tunnels includes inner and outer downwardly divergent surfaces including major portions that are substantially planar and corresponding longitudinal edge portions of the inner surfaces of the tunnels are disposed in a first plane spaced below a second plane containing the lower longitudinal marginal edge portions of the corresponding outer surfaces. In this manner a basically V-shaped hull is formed and yet a hull including longitudinally extending and downwardly opening tunnels which, in addition to trapping air in the forward portion thereof and providing a means for cushioning the ride afforded by the boat hull, give rise to many advantages of operation as a result of their particular configuration as will hereinafter be more fully set forth.

The main object of this invention is to provide a boat hull which is basically V-shaped in transverse vertical section and which includes longitudinally straight and downwardly opening generally inverted V-shaped tunnels disposed on opposite sides of the longitudinal centerline of the hull.

Another object of this invention, in accordance with the immediately preceding object, is to provide each of the tunnels with a smoothly and forwardly and upwardly curving forward portion disposed in the bow portion of the hull and which, when the boat hull is moving at high speed, will increase the lift of the hull in a manner such that only a narrow center strip of the planing surfaces of the hull are disposed in cont-act with the water when the hull is moving at high speed thereby appreciably reducing the wetted area of the hull and thus the hull to water friction, therefore increasing speed as compared to conventional designs.

Still another object of this invention is to provide the downwardly opening tunnels of the boat hull of the instant invention with downwardly divergent opposite side surfaces which are substantially planar and form an included angle exceeding 90 degrees. With this type of construction forward movement of the hull through the water and the downward thrust of the hull on the water will cause the upwardly and'outwardly inclined inner surfaces of the tunnels to cause water to be rapidly displaced upwardly and outwardly along the inner surfaces of the tunnels and toward the downwardly and outwardly inclined outer surfaces of the tunnels thereby enabling the momentum or kinetic energy of the water displaced to apply a lifting thrust on the outer surfaces of the tunnels, thereby allowing the hull to carry greater load per horse power than conventional designs. In most instances, because of the desired overall V-shaped configuration of the hull, the upwardly and outwardly inclined inner surfaces of the tunnels will be of considerably greater width than the downwardly and outwardly inclined outer surfaces of the tunnels and in addition the upwardly and outwardly inclined inner surfaces of the tunnels will be disposed at a greater angle relative to a vertical plane than 3,330,239 Patented July 11, 1967 the downwardly and outwardly inclined outer surface of the tunnels.

Yet another object of this invention is to provide a tunneled boat hull construction which is basically V- shaped in transverse cross-section and which includes structural features which adapt the hull for use in calm water as well as rough water.

Another object of this invention, in accordance with the immediately preceding object, is to provide a boat hull construction including longitudinally extending and downwardly opening generally V-shaped tunnels disposed relative to each other and including inclined surfaces which adapt themselves for slight variations in construction and design in a manner enabling a basic design of boat hull to be followed with only slight modifications thereto being required to specifically adapt the boat hull for use in smooth or rough water and to be utilized to carry heavy or light loads.

Still another object of this invention is to provide a boat hull construction that is well suited for inboard as well as outboard motor installations and which is further well suited for use in construction of inboard bulls and Outboards hulls as well as sea plane hulls and other planing apparatus.

Still another object of this invention is to provide a boat hull construction including structural features which specifically adapt the boat hull to afford an air cushioned ride while simultaneously reducing the wetted area of the hull.

A further object of this invention is to provide a boat hull including structural features that enable any and all water displaced transversely outwardly away from the longitudinal centerline of the hull in response to rapid forward movement of the hull over a body of water to be deflected downwardly as opposed to upwardly and outwardly thereby providing a boat hull which is extremely dry.

Yet another object of this invention is to provide a boat hull constructon including structural features adapting the hull for use with single propeller installations as well as dual propeller installations while simultaneously providing the desired V-shaped hull and also reducing the draft of the boat hull relative to the draft of a conventional V-shaped hull.

Another object of this invention is to provide a boat hull construction that due to the tunnels and tunnel surfaces maintains positive control and maneuverability in any type of seat at any speed range.

Another object of this invention is to provide a boat hull construction including structural features that provide superior stability to the craft at rest and in motion.

Another object of this invention is to provide a boat hull construction including structural features which due to their configuration lends additional inherent strength to the bottom material, therefrom providing a stronger bottom structurally than conventional hull designs.

Another object of this invention is to provide a boat hull construction including structural features that allow ram air to enter beneath the hull and become trapped and compressed and as it passes aft along the hull to cushion the ride and break up skin friction on the tunnel surfaces.

A final object of this invention to be specifically enumerated herein is to provide a tunneled V-bottom boat hull in accordance with the preceding objects which will conform to conventional forms of manufacture, be readily adaptable to minor configuration variations and highly eflicient in operation so as to provide a hull that will be economically feasible, readily adaptable for use 0n rough and smooth water and for maximum speed and stability.

These together with other objects and advantages which will become subsequently apparent reside in the details of ii construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIGURE 1 is a bottom plan view of the boat hull of the instant invention;

FIGURE Z is a side elevational view of the boat hull of the instant invention;

FIGURE 3 is a front elevational view of the boat hull of the instant invention shown on somewhat of an enlarged scale; 7

FIGURE 4 is a diagrammatical view of the cross-sectional shape of the boat hull of the instant invention illustrating the manner in which the boat hull affords exceptional stability while executing a turn;

FIGURE 5 is a diagrammatical view of the cross-sectional shape of the boat hull of the instant invention showing the manner in which it is particularly well adapted for dual motor installation and also the manner in which the overall draft of the .boat hull is substantially reduced by its particular configuration and its adaptability for dual motor installation;

FIGURE 6 is a further diagrammatical view of the cross-sectional shape of the center portion of the boat hull of the instant invention illustrating the manner in which it is particularly well adapted for single motor installation and also the manner in which the draft of the boat hull of the instant invention is reduced relative to the draft of a conventional V-bottorn hull including a single propeller;

FIGURE 7 is still another diagrammatical view of the cross-sectional shape of the boat hull of the instant invention but showing a slightly modified cross-sectional contour;

FIGURES 8 and 9 are two additional diagrammatical views of two further modified cross-sectional shapes of the boat hull of the instant invention;

FIGURE 10 is yet another'diagrammatical view of the cross-sectional shape of a hull constructed in accordance with the present invention and illustrating a further modification thereof including a center generally V-shaped wedge and also illustrating the manner in which the wetted area of the boat hull is progressively reduced as the speed a of the hull over the surface of a body of water is increased and'also with still another modification of the cross-sectional shape of the hull illustrated in phantom lines;

FIGURE 11 is a diagrammatical view of the cross-sectional shape of the boat hull of the instant invention similar to that of FIGURE 10 but showing another modified form of boat hull;

FIGURE 12 is a diagrammatical view of the cross-sectional shape of yet another form of boat hull constructed in accordance with the present invention which defines a deeper V-shaped hull; and 7 FIGURE 13 is a diagrammatical view of the cross-sectional 'shape of the ,boat hull constructed in accordance with the present invention and with a further modified form of boat hull shown in phantom lines.

Referring now more specifically to the drawings the numeral 10 generally designates the boat hull of the instant invention which may be seen to include

opposite sides

12 and 14 interconnected by means of a transom 16 and a bottom generally referred to by the reference numeral 18 including a forwardly and upwardly curving bow portion 20 and a substantially longitudinally straight planing portion 22. The bottom 18 defines a longitudinal centerline 24 and a plurality of downwardly opening and longitudinally extending generally inverted V-

shaped tunnels

26, 28 and'30. The

tunnels

26, 28, and are sub Vstantially straight in the planing portion 22 and include forward extensions 26', 28' and 30 which smoothly curve forwardly and upwardly in the bow portion 20, the extensions 28' and 30 also curving inwardly toward the center tunnel 26.

Tunnels

28 and 30 plus any additional lift 7 and stability tunnels which smoothly curve forwardly and r 4 upwardly may also be run substantially parallelto the longitudinal centerline in ing the performance characteristics to any extent.

With attention now invitedto FIGURE 12 of the drawings there may be seen a modified form of boat hull generally referred to by the reference numeral 32 and which includes a center tunnel 34 corresponding to the tunnel 26 and a first pair of opposite side tunnels 36 corresponding to the opposite side tunnels 28. The

tunnels

36 and 28 define lift tunnels and it may be seen that the hull 32 additionally includes a second pair of lift tunnels 38. Then, disposed outwardly of the second pair of lift tunnels 38 the hull includes a pair of inner stabilizing tunnels 40 correspondingto the stabilizing tunnels 30 and a second pair of outer stabilizing tunnels 42.

Each of the

tunnels

36, 38, 40 and 42 includes a pair of downwardly divergent opposite side inner and outer surfaces A and B. The included angles formed between corresponding inner and outer surfaces A and B is greater than 90 and it may be seen by the arrows disposed in the

tunnels

36, 38, 40 and 42 at the left side of FIGURE 12 that any downward force of the boat hull 32 on a body of water while the boat hull 32 is traveling at good speeds will cause quantities of water to be rapidly displaced upwardly and outwardly along the inclined inner surfaces A and to be directed against the downwardly and outwardly inclined surfaces B thereby enabling the hull construction 32 to harness the kinetic energy of'the laterally and a upwardly displaced water impinging upon the downwardly and outwardly inclined outer surfaces A to apply an upward lifting force on the hull construction32.

With attention now invited to FIGURE 11 of the drawings there may be seen a modified form of boat hull construction generally referred to by the reference numeral 46 and which is similar to the hull construction 32. Horizontal broken lines C, D and E designate the water lines of the hull construction 46 while traveling at slow speeds, intermediate'speeds and high speeds, respectively. It is believed that it may be readily appreciated that the greater the speed of the hull construction 46 the greater will be the upward lifting force of the water applied to the hull construction 46 as explained above in connection with the harnessing of the kinetic energy of the water displaced upwardly and outwardly along the inner surfaces A and impinging upon the outer surfaces B plus the air lift and kinetic water lift imparted on the center tunnel, the air being compressed and acting as a shock absorber cushioning the ride and breaking up ,skin friction on its surfaces.

Although extreme cases may prove exception" to the rule, the downwardly and outwardly inclined outer surfaces B are to be disposed at an angle falling between 40 and degrees from a vertical plane and therefore the surfaces A, the inner surfaces of the tunnels, are disposed at an angle inclined at least 10 degrees from a horizontal plane.

It may be noted that the boat hull construction 46 illustrated in FIGURE 11 of the drawings includes a center tunnel 50 but that a similar hull construction illustrated in FIGURE 10 of the drawings and generally designated by the reference numeral 52 includes a center generally V-shaped wedge 54 in lieu of the center tunnel 50. The

center V-shaped wedge 54 may be utilized in lieu of the center inverted V-shaped tunnel when a boat hull is de signed with at least one'pair of lift tunnels and one or more pairs of stability tunnels. The terms lift and stability. as referred to the tunnels is used for clarity and are intera changeable. Each tunnel acts as a lift and/or stability tunnel. i

The water levels or lines F, G and H shown in FIG- URE 10 of the drawings further illustrate the manner in which the kinetic energy of the laterally and outwardly displaced water caused by forward movementof the hull constructed in accordance with the present invention may be harnessed by the outer downwardly and outwardly inbow portion 20 without chang clined surfaces of the tunnels and utilized to eflfect an upward lifting force on the hull which increases as the forward speed of the hull increases.

With attention now directed to FIGURES 5 and 6 of the drawings there may be seen diagrammatically illustrated a pair of

marine propellers

54 and 56 shown in their positions partially embraced in the lifting tunnels 58 disposed on opposite sides of the center tunnel 60 of the hull construction generally referred to by the reference numeral 62. The outline of a conventional V-shaped hull is generally designated by the reference numeral 64 and it may be seen that a dual propeller installation diagrammatically illustrated by the phantom line showings of the propellers 66 and 63 requires considerably more draft. In addition, a single propeller installation may be seen to be illustrated in FIGURE 6 of the drawings by the diagrammatical showing of the propeller 70 partially embraced by the center tunnel 72 of a hull construction generally referred to by the reference numeral 74. The outline of a conventional V-shaped hull is also illustrated in FIGURE 6 of the drawings by phantom lines 76 and an accompanying single marine propeller is designated by the reference numeral 78. The increase in draft of the conventional V-shaped hull construction provided with a single propeller installation over the draft of the hull construction 74 provided with a single propeller installation is designated by the distance J. Therefore, it may be seen from a comparison of FIGURES 5 and 6 of the drawings that a hull construction in accordance with the present invention and including a center tunnel is particularly well adapted for shallow draft operation with dual propellers and that the same type of hull construction is also particularly well adapted for use with single propeller installation and also provides a reduced draft as compared to the draft of a conventional boat hull construction utilizing a single propeller installation.

With attention now directed to the modified hull construction illustrated in FIGURES 8 and 9 of the drawings and generally referred to by the

reference numerals

80 and 82, it may be seen that the lower longitudinal edge portions of the cut waters 84 defined between adjacent tunnels of the hull construction 80 are generally semi-cylindrical in configuration. Additionally it may be seen from the showing in FIGURE 9 of the drawings that the tunnels of the hull construction 82 are separated by means of generally horizontal longitudinally extending narrow planing surfaces 86.

Although the lower portions of the cut waters defined between adjacent tunnels of the

hull constructions

80 and 82 are somewhat modified, the operation of these hull constructions remains substantially the same as the hull constructions disclosed herein which are substantially V-shaped in transverse outline.

With attention now directed to FIGURE 7 of the drawings there may be seen a still further modified form of hull construction generally referred to by the reference numeral 90 and which includes a plurality of longitudinally extending tunnels which are generally inverted V- shaped in cross-section but which include generally

semicylindrical apices

92, 94, 96 and 98. Again, while the cross-sectional outline of the tunnels of the hull construction 90 has been modified to some degree, the operation of the hull construction 90 remains substantially the same as the other hull constructions disclosed herein.

In FIGURE 4 of the drawings a hull construction generally referred to by the reference numeral 100 and generally corresponding to the hull construction is illustrated and is shown executing a turn at high speed with the centrifugal forces caused by the high speed turn being indicated by the arrow 102. The inner tunnel surface 104 is being advanced against the water 106 and acts to upwardly deflect the side of the boat hull construction 100 on the outside of the turn by its planing action with the water 106 and by deflecting the water upwardly and into impingement with the corresponding outer side tunnel surface 108. This upwardly deflected water is strapped by the outer side tunnel surface 108 causing the tunnel to be filledwith water and, therefore, supplying a constant volume of water to the outboard propeller while turning. In this manner cavitation and thus loss of power is sequenced. Additionally, it will be noted that the outer tunnel side surface 108 is still downwardly and outwardly inclined and therefore that the spray effected by the boat hull construction executing a turn at high speed is deflected downwardly toward the surface of the water 106. Additionally, it will be noted that the

outer surfaces

110, 112 and 114 of the

tunnels

116, 118 and 120 act as keels to minimize side slipping of the hull construction 100 while the latter is executing the turn at high speed.

With attention now invited to FIGURE 13 of the drawings there may be seen yet another modified form of hull construction generally referred to by the reference numeral 124. The hull construction 124 includes a center tunnel 126, two pairs of opposite

side lift tunnels

128 and 130 and two pairs of opposite

side stabilizing tunnels

132 and 134. The transverse width of the outer surface 136 of the tunnel 128 on the righthand side of FIGURE 13 is designated as an unknown distance Y. The corresponding inner surface 138 has a transverse width greater than three times the width Y. Although variations in the ratio of the width of the surfaces 138 and 136 may vary, it is to be noted that this ratio will be at least 2 to 1. In addition, it may be seen that the transverse width of the outer side of the tunnel 128 disposed on the lefthand side of the figure is designated as X and that the transverse width of the inner side of the tunnel 128 on the lefthand side of FIGURE 13 is designated as greater than four times X and not less than 2 to 1. Again, although the ratio between the transverse width of the inner and outer sides of the tunnels of the hull construction 124 may vary, it is to be understood that this ratio will not exceed 5 to l.

All of the various tunnels of the various hull constructions disclosed herein fall within these ratio limits and these ratio limits have been found to offer the most desired operational advantages of hull constructions constructed in accordance with the present invention. Additionally, it is to be noted that the included angles formed by corresponding inner and outer surfaces of all of the tunnels disclosed herein are greater than 90 degrees as previously set forth in connection with the hull construction 32 illustrated in FIGURE 12 of the drawings. Still further, the phantom line illustration in FIG- URES 6, 7 and 10-13 illustrate further modified forms of hull constructions which include on less pair of tunnels than the corresponding form of the invention illustrated in solid lines.

In actual controlled tests as a result of the construction and testing of numerous hull constructions such as those illustrated in the present invention and other modifications operating on the same principles of lift as described herein, it has been found that the hull construction that is provided with a deeper overall V in transverse section as is illustrated in FIGURE 12 as compared to a shallower overall V in transverse section as in FIG- URE 13 operates in a superior manner in rough water at sea. The converse of these situations would then obviously also apply with a shallower V-shaped hull. The shallower overall V-shaped hull operates in a superior manner when used in shallower waters such as bays, lakes, and sounds due to higher load capabilities and shallower draft plus a corresponding speed increase with equal horsepower. Thus, both minor modifications work under the same tunnel principles at the present invention with only a change in the degree of efiectiveness.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention 4 plane containing the lower longitudinal the last-mentioned outer surfaces.

r 7 to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be restored to, falling within the scope of the invention as claimed.

What is claimed as new is as follows:

1. A boat hull including a bottom substantially V-shaped in transverse cross-section, said bottom defining a forward upwardly and forwardly curving bow portion and a substantially longitudinally straight aft planing portion, said planing portion of said bottom defining a longitudinal center line and at least one pair'of downwardly opening generally inverted V-shaped and longitudinally staright lift tunnels extending along opposite sides of said center line, each of said tunnels including inner and outer downwardly divergent surfaces including major portions that are substantially planar, said inner surfaces being downwardly and inwardly inclined and said outer surfaces being downwardly and outwardly inclined, the angle of said inner surfaces relative to the dead rise of said hull being less than 30 degrees and said outer surfaces being inclined at least degrees relative to a horizontal plane.

2. The combination of claim 1 wherein said center line is defined by the apex of a center generally inverted V-shaped center tunnel disposed between said lift tunnels.

3. The combination of claim 1 wherein said center line is defined by a depending generally V-shapedcenter wedge defined by the lowermost inner surfaces.

4. The combination of claim 1 wherein said planing portion of said bottom includes at least a first pair of opposite side generally inverted V-shaped stabilizing tunnels disposed immediately outwardly of the corresponding lift tunnels and also including inner and outer downwardly divergent surfaces including major portions that are substantially planar, corresponding lower longitudinal edge portions of the last-mentioned inner surfaces being generally disposed in said second plane and below a third plane containing the lower longitudinal edge portions of the last-mentioned outer surfaces.

5. The combination of claim 4 wherein said planing portion of said bottom includes a second pair of opposite side inverted V-shaped stabilizing tunnels, the second pair of stabilizing tunnels being disposed immediately outwardly of said first pair of stabilizing tunnels and including inner and outer downwardly divergent surfaces also including major portions that are sub.- stantially planar, the corresponding lower longitudinal edge portions of the last-mentioned inner surfaces being generally disposed in said third plane and below a fourth edge portions of 6. The combination of claim 1 wherein said planing portion of said bottom includes at least a first pair of op posite side generally inverted V-shaped stabilizing tunnels disposed immediately outwardly of the corresponding lift tunnels and also including inner and outer downwardly divergent surfaces including major portions that are substantially planar, corresponding lower longitudinal edge portions of the last-mentioned inner surfaces being generally disposed in said second plane and below a third plane containing the lower longitudinal edge portions of the last-mentioned outer surfaces, the included angles formed by corresponding inner and outer surfaces of said tunnels is greater than 90 degrees.

7. The combination of claim 1 wherein the ratio of the transverse width of said inner and outer surfaces of each of said lift tunnels measured in a horizontal plane is at least two to one.

8. The combination of claim 1 wherein the ratio of the transverse width of said inner and outer surfaces of each of said lift tunnels measured along said inner and outer surfaces is less than five to one.

9. The combination of claim 8 wherein the included angles formed by corresponding inner and outer surfaces of said lift tunnels is greater than 90 degrees.

10. The combination of claim 9 wherein the ratio of the transverse width of said inner and outer surfaces of each of said lift tunnels measured in a horizontal plane is at least two to one.

11. The combination of claim 1 wherein. said tunnels on opposite sides of said centerline include forward extensions thereof smoothly curving forwardly and upwardly at their forward ends into said bow portion.

12. The combination of claim 11 wherein said forward extensions also curve forwardly and inwardly toward said centerline 13. The combination of claim 1 wherein said tunnels immediately adjacent said centerline are of a width adapted to span the diameter of a marine propeller.

14. The combination of claim 1 wherein said centerline is defined by the apex of a center generally inverted V- shaped center tunnel disposed between said lift tunnels, said center tunnel being of a width adapted to span the diameter of a marine propeller.

'15. The combination of claim 1 wherein said outer surfaces are inclined downwardly and outwardly at an angle between forty and eighty degrees from a vertical plane. 7

16. The combination of claim 1 wherein the included angles formed by corresponding inner and outer surfaces of said lift tunnels is greater than degrees.

17. The combination of claim 1 wherein the ratio Of the transverse width of said inner and outer surfaces of each of said lift tunnels measured along said surfaces is between 2 to 1 and 4 to 1.

18. The combination of claim 1 wherein the ratio of the transverse width of said inner and outer surfaces of each of said lift tunnels measured along a horizontal plane is between 5 to 1 and 2 to 1.

19. The combination of claim'l wherein the ratio of the transverse width of said inner and outer surfaces of each of said tunnels measured along said surfaces is at least 2 to 1.

20. A boat hull including a bottom substantially V- shaped in transverse cross-section, said bottom defining a forward upwardly and forwardly curving bow portion and a substantially longitudinally straight aft planing portion, said planing portion of said bottom defining a longi tudinal center line and at least one pair of downwardly opening generally inverted V-shaped and longitudinally straight lift tunnels extending along opposite sides of'said center line, each of said tunnels including inner and outer downwardly divergent surfaces including major portions that are substantially planar, said inner surfaces being downwardly and inwardly inclined and said outer surfaces being downwardly and outwardly inclined, the in,- cluded angles formed by the corresponding inner and outer surf-aces of said tunnels being generally 90 degrees and the ratio of the transverse width of said inner and outer surfaces of each of said tunnels measured alon said surfaces being at least 2 to 1.

21. The combination of claim 20 wherein the outer surfaces of said tunnels are inclined at least 10 degrees relative to a horizontal plane.

References Cited UNITED STATES PATENTS Thorsen ll456 MILTON BUCHLER, Primary Examiner.

T. M. ,BLIX, Assistant Examiner.

Claims

1. A BOAT HULL INCLUDING A BOTTOM SUBSTANTIALLY V-SHAPED IN TRANSVERSE CROSS-SECTION, SAID BOTTOM DEFINING A FORWARD UPWARDLY AND FORWARDLY CURVING BOW PORTION AND A SUBSTANTIALLY LONGITUDINALLY STRAIGHT AFT PLANING PORTION, SAID PLANING PORTION OF SAID BOTTOM DEFINING A LONGITUDINAL CENTER LINE AND AT LEAST ONE PAIR OF DOWNWARDLY OPENING GENERALLY INVERTED V-SHAPED AND LONGITUDINALLY STARIGHT LIFT TUNNELS EXTENDING ALONG OPPOSITE SIDES OF SAID CENTER LINE, EACH OF SAID TUNNELS INCLUDING INNER AND OUTER DOWNWARDLY DIVERGENT SURFACES INCLUDING MAJOR PORTIONS THAT ARE SUBSTANTIALLY PLANAR, SAID INNER SURFACES BEING DOWNWARDLY AND INWARDLY INCLINED AND SAID OUTER SURFACES BEING DOWNWARDLY AND OUTWARDLY INCLINED, THE ANGLE OF SAID INNER SURFACES RELATIVE TO THE DEAD RISE OF SAID HULL BEING LESS THAN 30 DEGREES AND SAID OUTER SURFACES BEING INCLINED AT LEAST 10 DEGREES RELATIVE TO A HORIZONTAL PLANE.