US3871317A

US3871317A - Watercraft

Info

Publication number: US3871317A
Application number: US379333A
Authority: US
Inventors: Jack J Szpytman
Original assignee: Individual
Current assignee: Individual
Priority date: 1973-07-16
Filing date: 1973-07-16
Publication date: 1975-03-18
Anticipated expiration: 1992-03-18
Also published as: JPS5032694A

Abstract

A watercraft with a tunnel providing one or more aerodynamic lifting surfaces, together with stabilizing fins in the form of hydroplanes or hydrofoils, and propulsion means aligned with the stabilizing fins. The combined effect of the lifting surfaces and stabilizing fins lifts the craft to reduce hydrodynamic resistance and provides enhanced roll and pitch stability. In a preferred form, the tunnel has two lifting surfaces in tandem, each surface being curvilinear and sloping downwardly and aftwardly at its rearward portion. Hydrofoils and hydroplanes are provided on the bottoms of the outer sponsons and an additional hydrofoil is mounted on an enlarged central forward portion of the hull. One propulsion means is mounted at the after end of the forward central hull portion and the other two at the after end of the sponsons, the hull propulsion means being aligned with the stabilizing fins.

Description

United States Patent [191 Szpytman Mar. 18, 1975 WATERCRAFT [76] Inventor: Jack J. Szpytman, 910 N. Brys Dr., Grosse Pointe Woods, Mich. 48236 [22] Filed: July 16, 1973 [21] Appl. No.: 379,333

[52] U.S. Cl ll4/66.5 R, l14/66.5 H, 115/67 R [51] Int. Cl B63b l/30 [58] Field of Search 1l4/66.5 R, 66.5 H, 66.5 P,

' ll4/66.5 F, 67 A, 61

Primary ExaminerRobert J. Spar Assistant-ExaminerDonald W. Underwood Attorney, Agent, or Firm-Harness, Dickey & Pierce [57] ABSTRACT A watercraft with a tunnel providing one or more aerodynamic lifting surfaces, together with stabilizing fins in the form of hydroplanes or hydrofoils, and propulsion means aligned with the stabilizing fins. The combined effect of the lifting surfaces and stabilizing fins lifts the craft to reduce hydrodynamic resistance and provides enhanced roll and pitch stability. In a preferred form, the tunnel has two lifting surfaces in tandem, each surface being curvilinear and sloping downwardly and aftwardly at its rearward portion. Hydrofoils and hydroplanes are provided on the bottoms of the outer sponsons and an additional hydrofoil is mounted on an enlarged central forward portion of the hull. One propulsion means is mounted at the after end of the forward central hull portion and the other two at the after end of the sponsons, the hull propulsion means being aligned with the stabilizing fins.

13 Claims, 5 Drawing Figures a" a 1; cicadas]: [113:1 27 g z z r WWW/[=7 mama a Y it n WATERCRAFT BACKGROUND OF THE INVENTION The invention relates to watercraft of the type utilizing aerodynamic forces created during motion to lift the craft at least partially out of the water, thus reducing the wetted surface and spray resistance, and increasing speed. The application is related to my US. Pat. No. 3,702,598 issued Nov. 14, 1972 and entitled Watercraft as well as to my application Ser. No. 205,017 filed Dec. 6, 1971.

BRIEF SUMMARY OF THE INVENTION use of mechanical systems.

It is another object to provide a watercraft of this nabulkhead 29. These compartments are utilizable for cargo purposes. If, for example, the watercraft is being used as a car ferry, vehicles 29 may be stored in these compartments, a ramp 31 being indicated partially in FIG. 1 for loading and unloading through an access opening 32.

ture having improved lateral or roll stability and which minimizes any torque effect on the hull caused by a vertical moment arm between the engine thrust and the stabilizing fins which might adversely affect the attitude of the vessel.

It is another object to provide an improved watercraft having these characteristics, in which prow and keel means are provided for protecting the hydrofoils from damage, acting as skirts for containing the air cushion and housing the hydrofoil adjusting means.-

Briefly, the watercraft of this invention comprises an elongated hull, an undersurface on said hull having a concavely curved aerodynamic lifting shape configured to provide an upwardly acting force applied to said craft in response to flow of air therealong, stabilizing fin means carried by laterally spaced portions of said hull below said aerodynamic lifting surface, and propulsion means carried by said hull.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view, partly in section, showing a watercraft incorporating the principles of this invention.

FIG. 2 is a bottom plan view thereof.

FIG. 3 is a cross-sectional view in elevation taken along the line 3-3 of FIG. 2.

FIG. 4 is an enlarged fragmentary detailed view of one of the hydrofoils and its adjusting mechanism.

FIG. 5 is an enlarged fragmentary cross-sectional view in elevation taken along the line 5-5 of FIG. 1 showing the construction of one of the hydroplanes.

DESCRIPTION OF THE PREFERRED EMBODIMENT The watercraft is generally indicated at 11 and comprises an elongated hull generally indicated at 12, the major portion of which is of rectangular shape in plan, as best seen in FIG. 2. Above the at-rest water line 13, hull 12 is provided with sides 14 which extend upwardly as shown in FIG. 3 and then slope inwardly, being joined by a cabin top 15 at their upper ends. Compartments l6, l7 and 18 are formed between top 15 and a deck 19, the compartments being separated by longitudinal bulkheads 21 and 22. These three compartments may be utilized for passenger purposes, lights 23, seats 24 and tables 25 being shown for this purpose. A second deck 26 extends between sides 14 below deck 19 with the space therebetween being divided into compartments 27 and 28 by a longitudinal The forward portion 33 of hull 12 is tapered and flared as seen in FIGS. 1 and 2. Hull portion 33 is deeper than the remainder of the hull (except for the sponsons to be described later) and its underside 34 is provided with ahydrofoil 35. The construction of the hydrofoil is seen best in FIGS. 1, 2 and 4. The hydrofoil is disposed within a recess 36 in hull bottom 34 and is pivoted at its forward end as indicated at 37. The hydrofoil is of airfoil shape and is actuatable between a recessed or cruising position shown in solid lines in FIG. 4 and a takeoff position shown in dot-dash lines. The solid line position is within recess 36 whereas the takeoff position has a greater angle of incidence to achieve added lift.

The means for actuating hydrofoil 35 may comprise a reciprocable fluid actuated motor 38 or other appropriate means disposed within hull portion 33.

Propulsion means in the form of a jet drive 39 is carried by hull bottom 34 rearwardly of and aligned with hydrofoil 35. The jet drive has a water intake 41 seen in FIG. 1. Alternative propulsion means such as a propeller could be used.

The hull bottom rearwardly of bottom portion 34 is generally indicated at 42 in FIG. 1 and comprises a pair of aerodynamic lifting surfaces 43 and 44 in tandem. The curvilinear shape of these surfaces is similar to that shown in my above-mentioned US. Pat. No. 3,702,598, each surface having an upwardly and aftwardly extending forward portion, a generally horizontal intermediate portion and a downwardly and aftwardly extending rearward portion. These portions are smoothly blended into an airfoil shape to provide surfaces which will impart substantial lifting forces to the craft when in movement, due to the air cushion effect. Bottom 42 has an intermediate portion 45 between surfaces 43 and 44 and an after portion 46. Portions 45 and 46 are flat lifting surfaces which blend smoothly with the aerodynamic surfaces immediately forwardly thereof.

Re-entrant portions 47 and 48 are formed at the forward ends of surfaces 43 and 44 respectively. The pockets created by these surfaces willtend to trap air and prevent it from escaping forwardly. Optionally, blowers 49 and 51 may be provided for delivering air to pockets 47 and 48 respectively. The combined effect of the pockets and blowers will counteract accumulated air cushion backup and assist in creating air buildup.

A pair of sponsons generally indicated at 52 are provided along opposite sides of the craft to form, together with bottom portion 42, a tunnel to entrap air which will actagainst aerodynamic surface 42. Sponsons 52 extend from the after end of hull portion 33 to the after end of the vessel and have faired bow portions 53 indicated in FIG. 1. The upper portions of the sponsons have outer side walls 54 contiguous with sides 14 and inner side walls 55, but the lower portions 56 are tapered to thin cross sections for lateral stability, as seen in FIG. 5. Flange type hydroplanes 57 are mounted along the bottoms of the sponsons. The shape of these hydroplanes is seen in FIG. 2, the hydroplanes gradually flaring in an after direction. These hydroplanes extend along a major portion of the sponsons and a pair of jet drives 58 are mounted in the after ends of the sponsons, the jet drives being aligned with the hydroplanes. These jet drives have water intakes 59 (FIG. 2), Jet drives 58 as well as drives 39 are provided with rudders 60 and 61 respectively mounted adjacent thereto.

A pair of hydrofoils 62 are mounted under the forward ends of sponsons 52 as seen in FIGS. 1 and 2. These hydrofoils are shaped similarly to hydrofoil 35 and are pivoted at their forward ends for movement from cruising positions within sponson recesses to lower or takeoff positions. Reciprocable motors 63 are provided for hydrofoils 62. The hydrofoils are aligned with hydroplanes 57 and thus with jet drives 58.

A keel member 64 extends centrally along bottom 42, the keel being directly under bulkhead 29. An airflow control leveler 65 is mounted at the after end of the vessel contiguously with flat surface 46, this leveler being actuatable by a reciprocable motor 66 to control the amount of air flow.

In operation, movement of the craft along the water will cause it to rise due to the combined effects of the stabilizing fins (hydroplanes and hydrofoils) and aerodynamic surface 42. The craft will rise so that the water line will be as indicated at 67 in FIGS. 1 and 3. The takeoff positions of hydrofoils 35 and 62 will facilitate rising'of the craft, after which the hydrofoils may be retracted to their cruising positions. Sponsons 54 will act to protect the hydrofoils from damage, as skirts for containing the air cushion impacting aerodynamic surface 42, and as lateral stabilizing means. Hydroplanes 57 will increase the lateral stability of the craft as well as contributing to the lifting action.

Because ofthe alignment of propulsion means 39 and 58, with the stabilizing fins (hydrofoils and hydroplanes) there will be little, if any, torque tending to affect the attitude of watercraft 11. This will facilitate keeping it on an even keel.

I claim:

1. A watercraft comprising an elongated hull, an under surface on said hull having a concavely curved aerodynamic lifting shape configured to provide an upwardly acting force applied to said craft in response to flow of air therealong, stabilizing fin means carried by laterally spaced portions of said hull below said aerodynamic lifting surface, each of said last-mentioned hull portions carrying said stabilizing fin means at its lower end, each of said stabilizing fin means having a generally flat horizontal lateral configuration in cross section with exposed downwardly facing and upwardly facing surfaces extending laterally outwardly on opposite sides of said lower end, and propulsion means carried by said hull, said aerodynamic lifting surfaces comprising two concave surfaces in tandem, each surface comprising an upwardly and aftwardly extending forward portion, a substantially horizontal intermediate portion, and a downwardly and aftwardly extending rearward portion, a flat surface being provided on the underside of the hull between said two aerodynamic sections.

2. The combination according to claim 1, said stabilizing fin means comprising a single pair of elongated hydroplanes fixed to sponsons on opposite sides of said lifting surface and extending along major portions of said sponsons.

3. The combination according to claim 1, said stabilizing fin means comprising a pair of hydrofoils movably mounted on opposite sides of said surface, and means for moving said hydrofoils between upper cruising positions and lower takeoff positions.

4. The combination according to claim 1, said propulsion means comprising a pair of propulsion units on opposite sides of said hull aligned with said stabilizing fin means.

5. The combination according to claim 4, said stabilizing fin means comprising aftwardly flared hydroplanes extending along the bottoms of sponsons on opposite sides of said surface.

6. The combination according to claim 5, said hull having a relatively deep forward portion, said stabilizing fin means further comprising a hydrofoil movably mounted beneath said forward hull portion, means for moving said hydrofoil between an upper cruising position and a lower takeoff position with a greater angle of incidence, and a propulsion unit carried by the after end of said forward hull portion and aligned with said hydrofoil.

7. The combination according to claim 1, further provided with a pair of relatively thin elongated sponsons along opposite sides of said hull, the forward ends of said sponsons being faired, said stabilizing fin means comprising a pair of hydrofoils pivotally mounted at their forward ends beneath said sponsons, said sponsons acting as skirts for containing the aircushion formed beneath said craft and impinging on said aerodynamic surface, reciprocable motor means within said sponsons connected to said hydrofoils for moving them between upper cruising positions and lower takeoff positions, and recesses in said sponsons for receiving and protecting the hydrofoils when in cruising position.

8. The combination according to claim 7, said propulsion means being carried by the after ends of said sponsons and being aligned with said hydrofoils.

9. The combination according to claim 8, the lower portions of said sponsons having relatively thin cross sections for lateral stability, said stabilizing fin means further comprising flange type hydroplanes fixed to the undersides of said sponsons and extending therealong.

10. The combination according to claim 1, the forward ends of said two aerodynamic lifting surface sections being reentrantly formed to provide pockets which tend to trap air so as to prevent the air from escaping forwardly.

11. The combination according to claim 10, further provided with blowers within said hull with their outlets connected to said last-mentioned pockets to counteract accumulated air cushion backup.

12. A watercraft comprising an elongated hull having a major portion of generally rectangular shape in plan and a forward tapered hull portion, said forward hull portion being deeper than the remainder of the hull, a hydrofoil pivotally mounted in a recess beneath said forward hull portion, reciprocable motor means within said forward hull portion for actuating said hydrofoil between an upper cruising position and a lower takeoff postion, propulsion means carried by the after end of said forward hull portion in alignment with said hydrofoil, an aerodynamic lifting surface on the underside of the main hull portion, said lifting surface having two sections in tandem, each section having an upwardly and aftwardly extending forward portion, a substantially horizontal intermediate portion and a downwardly and aftwardly sloping rear portion with the portions being blended together to provide a concave curvilinear surface creating an upwardly acting aerodynamic force in response to flow of air therealong, a pair of sponsons extending downwardly on opposite sides of said hull alongside said lifting surface to form a tunnel therewith, a pair of hydrofoils pivotally mounted in recesses under the forward ends of said sponsons, reciprocable motor means within said sponsons for moving said last-mentioned hydrofoils between cruising and takeoff positions, fixed flange type hydroplanes secured to the undersides of said sponsons and extending therealong in alignment with said last-mentioned hydrofoils, and a pair of propulsion units at the ends of said sponsons and in alignment with said hydroplanes.

13. A watercraft comprising an elongated hull, an undersurface on said hull having a concavely curved aerodynamic lifting shape configured to provide an upwardly acting force applied to said craft in response to flow of air therealong, stabilizing fin means carried by laterally spaced portions of said hull below said aerodynamic lifting surface, each of said last-mentioned hull portions carrying said stabilizing fin means at its lower end, each of said stabilizing fin means having a generally flat horizontal lateral configuration in cross section with exposed downwardly facing and upwardly facing surfaces extending laterally outwardly on opposite sides of said lower end, and propulsion means carried by said hull, said aerodynamic lifting surface comprising a plurality of surface sections extending from front to rear each surface section comprising an upwardly and aftwardly sloping forward portion, a substantially horizontal intermediate portion, and a downwardly and aftwardly sloping rearward portion, said surface sections being longitudinally aligned with one another and located between said laterally spaced hull portions, with said portions being blended together in curvilinear fashion and each surface section connected with the preceding surface section by a substantially horizontal intermediate section.

Claims

1. A watercraft comprising an elongated hull, an under- surface on said hull having a concavely curved aerodynamic lifting shape configured to provide an upwardly acting force applied to said craft in response to flow of air therealong, stabilizing fin means carried by laterally spaced portions of said hull below said aerodynamic lifting surface, each of said last-mentioned hull portions carrying said stabilizing fin means at its lower end, each of said stabilizing fin means having a generally flat horizontal lateral configuration in cross section with exposed downwardly facing and upwardly facing surfaces extending laterally outwardly on opposite sides of said lower end, and propulsion means carried by said hull, said aerodynamic lifting surfaces comprising two concave surfaces in tandem, each surface comprising an upwardly and aftwardly extending forward portion, a substantially horizontal intermediate portion, and a downwardly and aftwardly extending rearward portion, a flat surface being provided on the underside of the hull between said two aerodynamic sections.

7. The combination according to claim 1, further provided with a pair of relatively thin elongated sponsons along opposite sides of said hull, the forward ends of said sponsons being faired, said stabilizing fin means comprising a pair of hydrofoils pivotally mounted at their forward ends beneath said sponsons, said sponsons acting as skirts for containing the air cushion formed beneath said craft and impinging on said aerodynamic surface, reciprocable motor means within said sponsons connected to said hydrofoils for moving them between upper cruising positions and lower take- off positions, and recesses in said sponsons for receiving and protecting the hydrofoils when in cruising position.