INFLATABLE HULL STRUCTURE AND METHOD OF FORMING AN INFLATABLE BOAT HULL

Abstract

An inflatable boat includes a bottom structure made up of two or more inflated bottom tubes. Each bottom tube extends along the longitudinal axis of the boat from the stern end of the boat to the bow end of the boat. The bottom tubes are arranged side-by-side along at least a portion of their length, and when in an inflated condition, may directly provide a portion of the hull surface for the boat or at least support further components which provide portions of the hull surface. A front end of preferably each bottom tube is raised vertically relative to a back end of the respective bottom tube at the stern of the boat, and the relative size and/or position of the bottom tubes may be selected to define a desirable hull profile for the boat such as a V-shaped hull profile.

Description

CROSS-REFERENCE TO RELATED APPLICATION

The Applicant claims the benefit, under 35 U.S.C. §119(e), of U.S. Provisional Patent Application No. 61/732,792 filed Dec. 3, 2012, and entitled “Inflatable Hull Structure and Method of Forming an Inflatable Boat Hull.” The entire content of this provisional application is incorporated herein by this reference.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to inflatable boats, and, more particularly, to an inflatable boat having an inflatable hull structure providing a desirable hydrodynamic shape. The invention also encompasses methods for forming an inflatable boat hull.

BACKGROUND OF THE INVENTION

Inflatable boats find application in a wide variety of situations. Inflatable boats may be used as utility runabouts for large vessels, as fishing boats, and as military landing or boarding craft. Despite their many desirable characteristics, prior inflatable boats have certain negative characteristics which reduce their usefulness. One undesirable characteristic of prior inflatable boats is that they provide a relatively unstable and low performance hull structure. In an effort to overcome this undesirable characteristic, some prior inflatable boats have been fitted with rigid hull material. However, employing rigid hull material has the disadvantage of negating some of the benefits of inflatable boats, in particular, light weight and portability. Other prior inflatable boat designs have employed an inflatable keel together with a frame and fabric arrangement in an effort to produce a more desirable hull shape for the craft. These designs tend to be complex and relatively difficult to set up and break down.

SUMMARY OF THE INVENTION

The present invention provides an inflatable boat that may have a desirable hull shape without requiring any rigid frame or coverings. In particular, an inflatable boat according to the present invention may use inflatable tubes to produce a V-shaped hull or other desirable hull shape. In the following disclosure and claims relative positional references such as front, rear, left, right, upper, lower, above, below, vertical, and horizontal refer to the orientation of the example embodiment shown in FIGS. 1 and 4 described below.

One embodiment of an inflatable boat according to the present invention includes a peripheral tube structure and two or more bottom tubes. The peripheral tube structure includes a right side tube and a left side tube which, in an inflated condition, define right and left sides of the boat respectively. These right and left side tubes of the peripheral tube structure may be referred to as the main buoyancy tubes of the inflatable boat. The right and left side tubes of the peripheral tube structure each extend along a longitudinal axis of the boat from a stern end of the boat to a bow end of the boat, and meet at the bow end of the boat. Each bottom tube (which may also be referred to as a “floor tube”) also extends along the longitudinal axis from the stern end of the boat to the peripheral tube structure at the bow end of the boat. The bottom tubes are arranged side-by-side along at least a portion of their length, and when in an inflated condition, define a bottom tube structure of the boat between the right side tube and left side tube. This bottom tube structure may directly provide a portion of the hull surface for the boat or at least support further components which provide portions of the hull surface. A front end of preferably each bottom tube is raised vertically relative to a back end of the respective bottom tube at the stern of the boat.

These and other advantages and features of the invention will be apparent from the following description of the preferred embodiments, considered along with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a rear view from an elevated perspective showing an inflatable boat according to one form of the present invention.

FIG. 2 is a rear view similar to FIG. 1, but showing a transom fitted to the inflatable boat.

FIG. 3 is a rear right side view in perspective of the inflatable boat in FIG. 1, but with the ends of the inflatable tubes removed so as to show the interior of each tube in the configuration it would reach in an inflated condition.

FIG. 4 is a right side view of the inflatable boat shown in FIG. 1

FIG. 5 is a perspective view in section taken along line 5-5 in FIG. 1.

FIG. 6 is a view similar to FIG. 5, but rotated so that the section along line 5-5 in FIG. 1 is viewed from the side rather than in perspective.

FIG. 7 is a transverse section view through a stern end portion of the bottom tubes of an inflatable boat according to a second embodiment of the invention.

FIG. 8 is a transverse section view through a stern end portion of the bottom tubes of an inflatable boat according to a third embodiment of the invention.

FIG. 9 is a transverse section view through a stern end portion of the bottom tubes of an inflatable boat according to a fourth embodiment of the invention.

FIG. 10 is a transverse section view through a stern end portion of the bottom tubes of an inflatable boat according to a fifth embodiment of the invention, showing an alternate arrangement for forming the bottom tubes.

FIG. 11 is a transverse section view through a stern end portion of the bottom tubes of an inflatable boat according to a sixth embodiment of the invention, showing another alternate arrangement for forming the bottom tubes.

FIG. 12 is a transverse section view through a stern end portion of the bottom tubes of an inflatable boat according to a seventh embodiment of the invention, showing a further alternate arrangement for forming the bottom tubes.

FIG. 13 is a transverse section view through a stern end portion of the bottom tubes of an inflatable boat according to an eighth embodiment of the invention, showing a bottom material attached to the bottom tubes.

FIG. 14 is a transverse section view through a stern end portion of an inflatable boat according to a ninth embodiment of the invention, showing an arrangement in which the bottom tubes are encased in a flexible foam or other material.

FIGS. 15A-C each show a diagrammatic representation along a transverse plane of a respective bottom tube configuration employing drop stitch chambers.

FIGS. 16A-C each show a diagrammatic longitudinal profile of a respective bottom tube style which may be employed in embodiments of the present invention.

FIG. 17A is a front perspective view showing an assembly of bottom tubes having curved, tapered, and rotated bow portions.

FIG. 17B is a front view of the assembly of bottom tubes shown in FIG. 17A.

FIG. 18A is a front perspective view showing an assembly of bottom tubes having constant-diameter curved bow portions.

FIG. 18B is a front view of the assembly of bottom tubes shown in FIG. 18A.

FIG. 19 is a front perspective view showing an assembly of bottom tubes in a tunnel hull configuration.

FIG. 20 is a diagrammatic rear view of an inflatable boat according to an embodiment of the invention, with the transom removed to show a floor structure connected to the bottom tubes to retain the bottom tubes in a desired configuration.

FIG. 21 is a side view of an inflatable boat according to another embodiment of the present invention.

FIG. 22 is a view in rear, left-side perspective of the inflatable boat of FIG. 21.

FIG. 23 is a front view in perspective from underneath the inflatable boat of FIG. 21.

DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

Referring to the embodiment shown in FIGS. 1-6, an inflatable boat 100 includes a peripheral tube structure 101 made up of a right side tube 102 and a left side tube 104. The right side tube 102 and left side tube 104 define right and left sides of the boat, respectively, and each extend along a longitudinal axis L of the boat from a stern end of the boat shown generally at 106 to a bow end of the boat shown generally at 108 (both ends labeled in FIGS. 1-4). The longitudinal axis L is shown in FIGS. 1 and 4, and, as indicated in FIG. 1, represents a centerline of the boat. The right side tube 102 and left side tube 104 meet at the bow end 108 of boat 100.

Inflatable boat 100 also includes two or more bottom tubes 110 that also extend along longitudinal axis L from the stern end 106 to the bow end 108 of the boat. When they are in an inflated condition the bottom tubes 110 define a bottom support structure of the boat connected between the right side tube 102 and left side tube 104. In the embodiment shown in FIGS. 1-6, a front end of each bottom tube 110 is connected to the peripheral tube structure 101 at the bow end 108 of the boat. As shown best in FIG. 6, each bottom tube has a front end that is raised vertically relative to other portions of the respective tube. The vertical offset is shown at dimension X between a lowermost level of the bottom tube and the lowermost surface of that bottom tube at its most forward point. The example in FIG. 6 shows bottom tube 110 intersecting peripheral tube structure 101 within the dimension Y. Other embodiments may extend the bottom tubes 110 below (or even conceivably above) the peripheral tube structure at the bow of the boat. FIG. 6 also shows that the peripheral tube structure 101 is also elevated at the front of the boat such that the side tube 104 (and tube 102 although not shown in FIG. 6) has a front portion raised vertically with respect to the back portion at the stern end 106 of the boat.

FIG. 6 shows an example waterline W for inflatable boat 100. This waterline W indicates the water level when the boat is resting in an operating position on a body of water. It will be noted from FIG. 6 and from the side view of FIG. 4 that a portion of the bottom tubes 110 extends below the side tubes 102 and 104. Thus portions of the bottom tubes 110 form the lowermost portion of the boat and boat hull.

The example of FIG. 5 shows that the bottom tube 110 through which the section is taken has a diameter slightly more than one-half the diameter of the left side tube. However, bottom tubes 110 may be smaller or larger than the side tubes 102 and 104. Some forms of the invention may include no peripheral tube structure such as structure 101 and may form the entire bottom of the boat from the side-by-side bottom tubes 110. Of course in these embodiments including no peripheral tube structure, the bottom tubes provide the main buoyancy for the boat.

As shown in FIG. 2, inflatable boat 100 may be fitted with a transom 120 which may receive an outboard motor (not shown). Transom 120 may be sealed to the right and left side tubes 102 and 104, and also sealed to the bottom tubes 110. In the form of the invention shown in FIG. 2, transom 120 is sealed to the ends of the bottom tubes 110 at the stern end 106 of boat 100.

FIGS. 1, 2, and 4 also show that the right and left side tubes 102 and 104 may each include a rearwardly tapered end portion 122.

The inflatable tubes employed in any of the embodiments of the present invention (such as tubes 102, 104, and 110 shown in FIGS. 1-6) may be formed from a tube chamber made of a flexible material and one or more air-tight bladders made of a suitable flexible material. The one or more bladders may be inserted into the respective chamber material and inflated to reach an inflated condition for that tube. Bladders may also be inflated first at least partially and then inserted into the respective tube chamber.

Alternatively, the tube chamber material itself may form an air-tight chamber made of a suitable material such as a rubber-coated or elastomer-coated fabric which may be inflated to reach an inflated condition for that tube.

The bottom tubes for a given embodiment (such as bottom tubes 110 in FIGS. 1-6) may be isolated and inflated separately, or may be connected so that all of the bottom tubes 110 may be inflated simultaneously.

Although the tubes 102, 104, and 110 are shown as single structures in the embodiment of FIGS. 1-6, each may be divided into separate chambers which are separately sealed and inflated. The portions of the right and left side tubes 102 and 104 at the bow end 108 of the boat in particular may be formed from several different chambers in order to help produce the desired upward offset.

One or more of the bottom tubes for a given embodiment may include or be entirely made of one or more drop stitch chambers having a suitable transverse shape, such as oblong for example, as shown in FIGS. 15A-C. The peripheral tube structure (including left and right side tubes 104 and 102 in the embodiment of FIG. 1) may also include drop stitch chambers.

The material forming the tube chambers may be connected in any manner suitable for the type of material, such as sonic welding, heat welding, adhesive material, sewing, or any combinations of these, for example.

Where connections are required between the various tubes (such as tubes 110, 102, and 104 in the embodiment of FIGS. 1-6), the connections may be made in any suitable fashion. FIGS. 7, 10, 11, and 12 illustrate several different arrangements for connecting the bottom tubes together in embodiments of the present invention. FIG. 7 shows bottom tubes 710 connected together with material strips 711. These connecting material strips 711 may be connected to the bottom tubes 710 via an adhesive, by a welding technique, or any other technique suitable to the connecting material and the tube material. The alternative embodiment of FIG. 10 shows that the various bottom tubes 1010 may be connected together with the same material forming the tube chambers for those tubes. The embodiments of FIGS. 11 and 12 show bottom tubes 1110 and 1210, respectively, which are also interconnected via the material which forms the tube chambers in those embodiments.

FIGS. 13, 14, and 20 each show a different arrangement for connecting or positioning the bottom tubes of the respective embodiment. In the example of FIG. 13, bottom tubes 1310 are retained together in the desired side-by-side position by a top material 1301 spanning the four bottom tubes, and by a foam material structure 1324 which includes a flexible or rigid bottom layer 1325. The example of FIG. 14 shows the bottom tubes 1410 completely incased in a foam material structure 1424. This foam material structure 1424 may be made in upper and lower halves (not shown in the figure), which may be placed together so as to trap the bottom tubes 1410 in the desired location relative to one another. A layer of upper cover material 1425 is shown extending between side tubes 1402 and 1404 to form the floor surface of the boat in this embodiment, while a bottom layer of material 1426 forms the exterior of the hull. FIG. 20 shows that a separate top member 2001 may be used to connect the bottom tubes 2010 together to provide the desired bottom structure between left and right side tubes 2004 and 2002, respectively. Top member 2001 may also provide a floor of the boat.

It will be appreciated from the embodiment of the invention shown in FIGS. 1-6, and from the embodiments of FIGS. 17A and 18A, that the bottom tubes of an inflatable boat according to the present invention need not be of the same length.

The present invention encompasses many variations regarding the bottom support structure formed from the bottom tubes. As shown particularly in FIGS. 7, 8, and 19, the number and size of the bottom tubes 710, 810, and 1910, respectively, connected together to produce the bottom support structure may be varied to approximate different hull shapes. The embodiment of FIG. 7 employs four bottom tubes 710 while the embodiment of FIG. 8 employs five bottom tubes 810. The embodiment of FIG. 19 includes nine bottom tubes 1910. Various hull shapes which may be approximated by various bottom tube configurations will be described further below.

The foam or other lightweight flexible material 1324 and 1424 shown in the embodiments of FIGS. 13 and 14, respectively, not only provides an arrangement for positioning the respective bottom tubes in those embodiments, but also provides a desired hull shape. In the case of FIG. 14, the material 1424 also provides a desired floor shape for the boat. FIGS. 16A-C show three different alternatives for the longitudinal shape of each bottom tube in an inflatable boat according to the present invention. FIG. 16A shows a bottom tube 1610A having a longitudinally curved front section. A number of bottom tubes 1610A may be used together according to the invention to provide an upwardly curved forward hull for the resulting boat. FIG. 16B shows a bottom tube 1610B having a front portion that is angled upwardly along a single line relative to the remainder of the bottom tube. FIG. 1610C shows an embodiment of a bottom tube 1610C having a front portion made up of multiple parts which together approximate an upward curve.

FIGS. 17A-B and 18A-B show two different arrangements of bottom tubes 1710 and 1810, respectively, arranged to form a respective bottom support structure for an inflatable boat according to the present invention. The arrangement of FIGS. 17A-B includes five separate bottom tubes 1710. Each bottom tube 1710 includes a rear section 1701 and a front section 1702, with each front section being curved upwardly and tapering in diameter toward the front of the structure. Because the bottom tubes 1710 taper smaller in diameter toward the front of the bottom structure, the outer two bottom tubes 1710 are angled inwardly. The angle for the outermost bottom tube 1710 is shown at R in FIG. 17B. The arrangement of FIGS. 18A-B also includes five separate bottom tubes 1810. Each bottom tube 1810 includes a rear section 1801 and a front section 1802 that is curved upwardly toward the front of the bottom structure but maintains a constant diameter. The upwardly curved or extending portions of the bottom tubes toward the front of the boat help generate lift at the bow of the boat as it is operated under power.

Although FIGS. 17A-B show that the bottom tubes 1710 all taper smaller in diameter toward the bow end of the boat, other arrangements may include some bottom tubes which increase in size toward the bow end of the boat, while other bottom tubes decrease in size. Furthermore, one or more of the bottom tubes may have a shape that includes a bulge. For example, the boat 2100 shown in FIGS. 21-23 includes a center bottom tube 2110 that includes a bulge at B to help fill the area between the adjacent bottom tubes where they curve upwardly. All of the bottom tubes 2110 are arranged between side tubes 2102 and 2104 similarly to the embodiment shown in FIGS. 1-6. The embodiment shown in FIGS. 21-23 also includes a transom 2120 mounted at the stern end of bottom tubes 2110.

As shown in FIG. 11, contact between two adjacent bottom tubes 1110 in the arrangement of bottom tubes may cause the bottom tube material to form essentially an I-beam shape which can contribute to the longitudinal stiffness of the boat. The I-beam shapes may or may not be reinforced with extra layers of material. Extra layers of material or different types of material in these regions may enhance stiffness of the resulting structure. In the example of FIG. 11, the I-beam shape between adjacent bottom tubes 1110 comprises pieces of material 1111 separate from an outer cover material 1112.

In some preferred forms of an inflatable boat hull according to the present invention, the bottom tubes, when in the inflated condition, lie side-by-side with essentially no gaps there between along the entire side-by-side length. Connecting material or an additional layer of material particularly along the bottom sides of the bottom tubes may be used to eliminate gaps between adjacent tubes. The bottom tube arrangement shown in FIG. 14 is an example where a bottom material 1424 fills the gaps between adjacent bottom tubes 1410.

One of the advantages of the present invention is that the arrangement of bottom tubes (bottom tubes 110 in FIGS. 1-6, for example) may form a complete hull for the boat. This complete hull may or may not be integral to the remainder of the boat. Also, the arrangement of bottom tubes may form an upper support surface which provides the floor or deck for the boat, or provides a support surface for one or more floor/deck members.

Another advantage of the present invention is that the side-by-side arrangement of elongated bottom tubes (bottom tubes 110 in FIGS. 1-6, for example) forms or approximates a desired hull profile (the profile being the shape along a line perpendicular to the longitudinal axis L of the boat). FIG. 7 shows a bottom structure made up of four bottom tubes 710 including two inner bottom tubes and two outer bottom tubes. The smaller diameter of the outer bottom tubes 710 and their position relative to the inner two bottom tubes 710 help approximate a V-shaped bottom shown by dashed line 701 and define a horizontal upper plane shown by dashed line 702. FIG. 8 shows an arrangement of five bottom tubes including a center bottom tube 810, two progressively smaller diameter bottom tubes 810 on either side of the center bottom tube. This arrangement of five bottom tubes 810 in FIG. 8 also approximates a V-shaped hull profile indicated by dashed line 801, and defines a horizontal top plane 802. FIG. 9 shows another way in which bottom tubes may be used to approximate a “V” hull profile. In the case of FIG. 9, all of the bottom tubes 910 have the same diameter, and a rigid structure or cross member 930 (or series of cross members spaced apart along the length of the bottom structure) connects across the top of two outside bottom tubes 910 (not necessarily the outermost bottom tubes) to force the bottom tubes 910 into the desired hull configuration. These two techniques, using different diameter bottom tubes 910, and using a rigid structure or cross member 930, may also be combined to produce a bottom tube arrangement having the desired hull profile. Additionally, as is particularly apparent from FIGS. 15A-C, the angular position at which adjacent bottom tubes are connected together may be used to influence the profile of the resulting hull. Although FIGS. 15A-C use drop stitch type, oblong bottom tubes 1510A, 1510B, and 1510C, respectively, the angular position connection technique may be used with circular bottom tubes or with other bottom tube transverse shapes. For example, the angular position of each outer bottom tube 710 shown in FIG. 7 with respect to the adjacent inner bottom tube 710 helps define the desired “V” shape 701. Also, angular connection position, bottom tube relative size, and a rigid top structure or cross member (such as cross member 930 in FIG. 9 for example) may be combined to produce the desired hull profile. Of course, the bottom tube relative size technique (illustrated in FIGS. 7 and 8 for example) may be used to create a desired hull profile using just the side-by-side bottom tubes without any rigid members needed to support the hull structure.

Although all of the illustrations show bottom tube arrangements including bottom tubes of a single transverse shape (for example, all circular in FIG. 8 and all oblong in FIG. 15A), forms of the invention may mix bottom tube shapes. For example, a center bottom tube may have a circular transverse shape (like center tube 810 in FIG. 8), and the outer bottom tubes may be oblong shaped (like tubes 1510A in FIG. 15A), or any other suitable shape or combination of shapes.

In a desirable hull configuration such as a “V” hull profile shown in FIG. 8 for example, the center bottom tube 810 provides the lowermost bottom surface of the boat. This tube providing the lowermost bottom surface may be referred to as a bilge tube since it makes up the lowermost chamber of the boat. The bottom of the adjacent bottom tubes 810 are raised vertically (direction Z in FIG. 8) with respect to the bottom surface of the bilge/center bottom tube 810. It will be appreciated that some desired hull shapes may include two spaced apart bilge tubes. FIG. 19 provides an example of such a hull structure produced by bottom tubes 1910 to form a double V-shaped hull profile.

As used herein, whether in the above description or the following claims, the terms “comprising,” “including,” “carrying,” “having,” “containing,” “involving,” and the like are to be understood to be open-ended, that is, to mean including but not limited to. Any use of ordinal terms such as “first,” “second,” “third,” etc., in the claims to modify a claim element does not by itself connote any priority, precedence, or order of one claim element over another, or the temporal order in which acts of a method are performed. Rather, unless specifically stated otherwise, such ordinal terms are used merely as labels to distinguish one claim element having a certain name from another element having a same name (but for use of the ordinal term).

The above described preferred embodiments are intended to illustrate the principles of the invention, but not to limit the scope of the invention. Various other embodiments and modifications to these preferred embodiments may be made by those skilled in the art without departing from the scope of the present invention.

Claims

1. An inflatable boat including:

(a) a peripheral tube structure including a right side tube and a left side tube which, in an inflated condition, define right and left sides of the boat, respectively, and each extend along a longitudinal axis of the boat from a stern end of the boat to a bow end of the boat, and meet at the bow end of the boat; and

(b) two or more bottom tubes which, in an inflated condition, define a bottom support structure of the boat extending laterally across the space between the right side tube and left side tube, each bottom tube extending along the direction of the longitudinal axis of the boat with a front end of each bottom tube raised vertically relative to a back end of the respective tube at the stern end of the boat, the bottom tubes residing side-by-side along at least a portion of their length to form the bottom support structure.

2. The inflatable boat of claim 1 wherein the peripheral tube structure is offset vertically in the bow end of the boat relative to the portion of the peripheral tube structure at the stern end of the boat.

3. The inflatable boat of claim 1 including three or more bottom tubes.

4. The inflatable boat of claim 1 wherein at least one of the bottom tubes intersects the peripheral tube structure at the bow end of the boat.

5. The inflatable boat of claim 1 wherein the bottom tubes are connected together by flexible connecting material to form the bottom tube structure.

6. The inflatable boat of claim 1 further including a floor member to which each bottom tube is connected to retain each bottom tube in a desired configuration relative to each other bottom tube.

7. The inflatable boat of claim 1 further including a bottom forming material positioned to receive one or more of the bottom tubes and provide a bottom surface for the inflatable boat.

8. The inflatable boat of claim 7 further including a top forming material positioned to receive one or more of the bottom tubes and provide a floor surface within the inflatable boat.

9. The inflatable boat of claim 1 further including a floor structure mounted above the bottom tubes.

10. The inflatable boat of claim 1 wherein one or more of the bottom tubes is tapered in the bow end of the boat to a smaller cross sectional dimension in the direction from the stern end of the boat to the bow end of the boat.

11. The inflatable boat of claim 10 wherein each tapered bottom tube has a tapered portion that curves upwardly toward the bow end of the boat.

12. The inflatable boat of claim 1 wherein each pair of adjacent bottom tubes define a respective upright I-beam segment of bottom tube material there between.

13. The inflatable boat of claim 1 wherein one or more of the bottom tubes comprises a bilge tube providing a lowermost bottom surface of the boat along a portion of its respective length and a bottom tube adjacent to one of the bilge tubes provides a lower surface which is raised vertically with respect to a lower surface of that bilge tube at least along a portion of the length of that bilge tube.

14. A method of forming an inflatable boat hull for a boat including a peripheral tube structure having a right side tube and a left side tube which, in an inflated condition, define right and left sides of the boat respectively and each extend along a longitudinal axis of the boat from a stern end of the boat to a bow end of the boat, and meet at the bow end of the boat, the method including:

(a) arranging two or more bottom tubes side-by-side to form a bottom tube assembly extending laterally in the area between the right side tube and the left side tube;

(b) connecting a front end of each bottom tube to the peripheral tube structure at the bow end of the boat with each bottom tube also extending rearwardly along the longitudinal axis of the boat to the stern end of the boat;

(c) connecting the bottom tube assembly at a right side thereof to the right side tube and connecting the bottom tube assembly at a left side thereof to the left side tube; and

(d) inflating each bottom tube to an inflated condition in which at least two or more of the bottom tubes include a front portion which is raised vertically with respect to a back portion of the respective bottom tube at the stern end of the boat.

15. The method of claim 14 wherein the bottom tube assembly includes one or more inflatable bladders contained in at least one of the bottom tubes and inflating each such bottom tube includes inflating the one or more inflatable bladders.

16. A boat including:

(a) two or more adjacent bottom tubes which, in an inflated condition, form a bottom structure making up at least a portion of a lowermost part of a hull of the boat, the lowermost part of the hull comprising a part located below a waterline for the boat when the boat is resting in an operating position on a body of water; and

(b) each bottom tube extending in the direction of a longitudinal axis of the boat and having a respective front end that is raised vertically with respect to at least a portion of that bottom tube.

17. The boat of claim 16 wherein the two or more adjacent bottom tubes include:

(a) one or more center bottom tubes having a first transverse dimension; and

(b) one or more outer bottom tubes outside of one of the one or more center bottom tubes, the one or more outer bottom tubes having a second transverse dimension smaller than the first transverse dimension of the one or more center bottom tubes.

18. The boat of claim 16 wherein the bottom structure includes a sufficient number of adjacent bottom tubes to extend laterally across the width of the boat to form an integral deck for the boat or an integral deck support surface.

19. The boat of claim 16 further including:

(a) an inflatable right side peripheral tube extending in the direction of the longitudinal axis along a right side of the bottom support structure to define a right side of the boat; and

(b) an inflatable left side peripheral tube extending in the direction of the longitudinal axis along a left side of the bottom support structure to define a left side of the boat, the right and left side peripheral tubes extending inwardly toward a centerline of the boat and meeting at a bow end of the boat, and the right and left side peripheral tubes defining a peripheral tube structure for the boat.

20. The boat of claim 19 wherein the bottom tubes intersect the peripheral tube structure at the bow end of the boat.