GB2350820A

GB2350820A - Monohull with longitudinal tunnels formed on the bottom

Info

Publication number: GB2350820A
Application number: GB0013840A
Authority: GB
Inventors: William Francis Pentecost
Original assignee: Individual
Current assignee: Individual
Priority date: 1999-06-08
Filing date: 2000-06-07
Publication date: 2000-12-13
Anticipated expiration: 2020-06-07
Also published as: WO2000075007A3; AU5237300A; GB0013840D0; GB2350820B; WO2000075007A2

Abstract

A monohull 1 has one or more longitudinally extending grooves or tunnels 2 formed externally on the bottom of the hull, said grooves in use having an upper portion 4 lying above the waterline 5 of the hull. The hull is also provided with drag reducing means which may be provided by the tunnels having a reduced cross-sectional area at the bow to restrict flow of water into the tunnel. The drag reducing means may also be provided by the tunnels having a contoured (10, Fig 3) or stepped (11, Fig 5) surface. The tunnels may be used to house an extending bowsprit (Fig 38), a spinnaker, a hydrofoil (19, Fig 42), propellers (18, Fig 6) or an outboard engine. The hull may be used to form a variety of different craft and may be propelled by a variety of different propulsion means.

Description

1 2350820 1 STABLE TUNNEL HULL 2 3 The present invention relates to an

improved monohull for 4 use on water craft. The monohull is especially, but not 5 exclusively, suitable for use on displacement and semi 6 displacement sea craft such as canoes, kayaks, dinghies, 7 punts and also rowing boats, motor boats, speedboats, 8 sailboats, keel boats and the like. The monohull is also 9 suitable for use on planing craft, and in particular load 10 carrying planing craft. 11 12 Tunnel hulled speed and sail boats are well known small, 13 light craft, so called because they have narrow sections 14 which can ride on water, separated by a wide tunnel which 15 allows air to be funnelled under the craft. The resultant 16 craft is a type of catamaran, having a monohull with 17 narrow pontoons which sit in the water whilst most of the 18 hull is suspended over the water. 19 20 Present tunnel craft are suited to low load bearing and 21 fast speed non- displacement or planing craft, as the 22 tunnel is used to give "lift" to the craft by virtue of---23 the passage of air through the tunnel. The craft must 24 travel at an appropriate speed to allow ehough 2 1 air to travel through the tunnel at once, in order to 2 lift the craft so that it is substantially suspended 3 over, and travels "on" the water. Conventionally tunnel 4 craft are not load carrying, displacement, semi5 displacement or planing craft. Displacement and semi6 displacement craft travel through, and displace water 7 from, their pathway and do not travel at sufficient 8 speeds to come onto the plane. Furthermore these types 9 of craft are usually too heavy in relation to their speed 10 to be suspended over the water by air flow through the 11 tunnel. 12 13 It is important that any sea craft, but in particular 14 small water craft such as canoes, kayaks, punts, and also 15 speedboats, motorboats and the like are relatively 16 stable. Small craft are generally considered to be those 17 up to 6 or 7 metres in length and tend to be from about 18 1.5 to 2 metres wide. Usually the hull of these crafts 19 narrow towards the bow, but widens at the transom. The 20 bow tends to have a sharp "V" profile and flattens 21 towards the aft of the boat such that the width of the 22 boat diminishes from the gunnels to the waterlines. As 23 the stability of the boat depends primarily on its width 24 at the waterline, this limits the stability of the craft. 25 It will be appreciated by anyone who has used a canoe or 26 kayak that it is relatively easy to capsize such a vessel 27 by sudden weight shift, i.e. if weight is moved from side 28 to side. It is also particularly difficult to re-embark 29 a canoe or the like after capsizing, due to their 30 instability. 31 32 Present attempts to make boat monohulls more stable 33 include making the beam wider, building weight in.,as.low 34 to the hull as possible and incorporating a keel.

3 1 However, extending the beam often results in unacceptable 2 drag, that is a considerably increased amount of power is 3 required to push the hull through or over the water due 4 to the extra wetted surface. As a consequence speed is 5 lost and an increased effort is required to move the boat 6 through the water. This is particularly problematic if 7 the boat is a paddle boat. Therefore a compromise is 8 usually chosen to produce a craft which may be less than 9 ideally stable, but which does not require prohibitive 10 amounts of energy to achieve a planning movement or reach 11 reasonable speed. 12 13 It will be appreciated that the inclusion of one or more 14 tunnels on a displacement, semidisplacement or planing 15 boat would unduly increase drag, as waves, water and air 16 would enter and the resultant increase in wetted surface 17 would provide a pressure build up. It is therefore an 18 object of the present invention to provide a boat 19 monohull which has superior stability over conventional 20 monohulls, which can be used on displacement, semi21 displacement or planing water craft, but which does not 22 significantly increase drag, or restrict the speed of the 23 water craft. 24 25 According to the present invention there is provided a 26 monohull boat having a monohull with one or more tunnels, 27 the one or more tunnels having a generally forward to aft 28 orientation, wherein the one or more tunnels define a dry 29 region located above the surface of the water, and 30 wherein the monohull has means for reducing drag. 31 32 Preferably the drag reducing means restricts water flow 33 into the one or more tunnels. 34 4 1 Optionally the drag reducing means is a constricted bow. 2 3 Typically, where the drag reducing means is a constricted 4 bow, the entrance of the one or more tunnels have a 5 reduced height and width relative to the height and width 6 of the tunnel further aft. 7 8 The drag reducing means may be provided by the one or 9 more tunnels having a width, which is less than 55% of 10 the average width of the monohull. 11 12 The drag reducing means may be provided by virtue of the 13 one or more tunnels having a surface which is adapted to 14 deflect water. 15 16 Optionally the surface of the one or more tunnels is 17 contoured. 18 19 Alternatively the surface of the one or more tunnels 20 comprises steps. 21 22 The one or more tunnels may provide part of the seating 23 in the monohull boat. 24 25 Optionally the one or more tunnels form a housing for an 26 extending bowsprit. 27 28 Optionally the boat may have one or more keels. The 29 keels can extend from the tunnels and may be fixed or 30 retractable. 31 32 The tunnel may form part of the deck or flooring support. 33 1 Optionally one or more hydrofoils may be located within 2 the one or more tunnels. 3 4 Optionally the one or more tunnels are adapted to house a 5 spinnaker or gennaker. 6 7 Optionally the contours in the one or more tunnels form 8 casing and support for centre plates, dagger boards, drop 9 plates or drop keels. 10 11 Optionally the one or more tunnels may house propellers. 12 13 The monohull boat may be a rowing boat such as a canoe, 14 punt, dinghy, kayak or the like. Alternatively the boat 15 may be motor powered such as a speed boat, inward or 16 outward powered motor boat, motor yacht, jet boat, 17 lifeboat, cabin cruiser or the like. The boat may be a 18 tender or a keel boat and may also be an inflatable boat, 19 rib or rigid inflatable boat. 20 21 The boat may be powered by kite, water jet, sail or more 22 than one means of propulsion. 23 24 Optionally the one or more tunnels comprise ropes which 25 act as safety lines in the event of the boat overturning. 26 27 A specific embodiment of the invention will now be 28 described by way of example with reference to the 29 accompanying drawings in which 30 31 Figure 1 is a cross section of a monohull with tunnel, 32 Figure 2 is a view of the under side of the monohull of 33 Figure 1 with tunnel, 6 1 Figure 3 shows a cross section of a monahull with a 2 contoured tunnel, 3 Figure 4 is a view of the underside of a monohull with 4 contours running parallel to the length of the tunnel, Figure 5 shows the underside of a monohull with steps 6 along the tunnel, 7 Figure 6 and 7 show respectively the underside and a bow 8 to stern hull view along the centre of a monohull craft 9 with cross section stations S1 to S6 marked along it, Figure 8 to 13 show transverse stations S1 to S6 as 11 marked on Figures 6 and 7, 12 Figure 14 is a cross section of a hull with a double 13 tunnel, 14 Figure 15 shows the under side of the twin tunnel hull of Figure 14, 16 Figure 16 shows a transverse section of a twin tunnel 17 hull with contoured tunnels, 18 Figure 17 shows the under side of a double twin tunnel 19 hull with contoured tunnel, Figure 18 shows an underside of a twin tunnel planing 21 hull with transverse cross sections XS1 to XS6, 22 Figure 19 shows a cut along the central keel line of the 23 twin tunnel hull of Figure 18 from bow to stern with XS1 24 to XS6 marked, Figure 20 to Figure 25 are views of cross sections XS1 to 26 XS6 from Figures 18 and 19, 27 Figure 26 shows a transverse section of a twin tunnel 28 hull with twin keels and a single motor between the 29 tunnels driving a propeller in the tunnels on each side, Figure 27 shows a twin tunnel hull with motors positioned 31 on the outside of each tunnel, 32 Figure 28 shows a transverse section of a twin tunnel 33 hull with motors in each part of the hull, 7 1 Figure 29 shows the underside of a twin tunnel 2 displacement hull or motor sailor hull type with 3 transverse sections MS1 to MS6 marked, 4 Figure 30 shows a cut from stem to stern of the twin tunnel hull of Figure 29 with transverse sections MS1 to 6 MS6, 7 Figures 31 to Figure 36 show cross sectional views of 8 MSI to MS6 relating to Figures 29 and 30, 9 Figures 36 and 37 show a keel fitted to twin tunnel hull, Figure 37 shows a twin tunnel hull.with motor between the 11 tunnels and central keel, 12 Figure 38 is a central cross section of a tunnel hull 13 from bow to stern with an extending bow sprit housing 14 located in the tunnel contours, Figure 39 shows a section of hull wall with a step 16 protruding into it, 17 Figure 40 shows a tunnel hull cross section with a 18 hydrofoil extending across the tunnel, 19 Figure 41 shows a tunnel hull cross section with a hydrofoil extending below the hull line, 21 Figure 42 shows the underside of a tunnel hull with two 22 hydrofoils across the tunnel, 23 Figure 43 shows the underside of a canoe with a tunnel 24 running from bow to stern, Figure 44 shows a cross section of a tunnel hull craft 26 where the tunnel also is a support for a seat, 27 Figure 45 shows a cross section of a tunnel hull kayak, 28 Figure 46 shows a bow or stern view of a tunnel hull 29 canoe, Figure 47 shows a bow or stern view of a tunnel hull 31 kayak, 32 Figure 48 shows a cross section of a tunnel hull where 33 the mast foot is located in the tunnel contour; and, 8 1 Figure 49 shows a tunnel hull where the centre 2 plate/dagger board housing is located in the tunnel 3 contour. 4 5 Referring firstly to Figure 1, a boat monohull is 6 generally shown in cross-section at 1. The hull (1) has 7 a tunnel (2) which runs in a generally forward to aft 8 orientation, parallel to the keel (6) of the monohull 9 (1). In the depicted embodiment, the hull (1) has one 10 tunnel (2) positioned in an essentially central location 11 relative to gunnels (3). The tunnel (2) may be of any 12 shape, but typically resembles a half tube or half box 13 section or an upturned half tube. It can be seen that 14 the roof (4) of the tunnel (2) is raised high above the 15 waterline (5) to create a dry region of the monohull 16 which is above the water. The tunnel (2) is also 17 substantially narrower than conventional tunnels. The 18 shaded areas (9) are located substantially below the 19 surface of the water and displace water as the boat 20 moves. The shaded areas (9) are described herein as the 21 wetted areas". The boat may be a keel boat with one or 22 more keels (6) which can be angled forward or aft. The 23 keels (6) can also be extended downward and outward to 24 provide extra lift. The keels (6) are an extension from 25 the sides of the tunnel (2) and may be fixed or 26 retractable. A double keel (6) may be provided on the two 27 wetted areas (9) of the hull (1) or as extensions of the 28 sides of the tunnel (2). 29 30 Figure 2 illustrates the same monohull boat as shown in 31 Figure 1, viewed from the underside, i.e., from under the 32 surface of the water. Figure 2 shows more clearly that 33 the tunnel (2) runs along the length of the hull (1) from 34 fore to aft, that is from bow (7) to stern (8) and 9 1 separates wetted areas (9) which sit substantially below 2 the surface of the water. The tunnel (2) defines area 3 (a) which is above the water line and is high enough to 4 clear wavelets, and which minimises wave slap and reduces 5 the wetted surface of the monohull (1), particularly 6 under calm conditions. It can also be seen from Figure 2 7 that the shape of the outer wetted areas (9) of the hull 8 (1) are asymmetric. 9 10 Turning now to Figure 3, a monohull (1) has a tunnel (2) 11 similar to the hull depicted in Figure 1. However, the 12 surface of the tunnel (2) has a plurality of contours 13 (10), which give lift to the hull (1) at speed and also 14 help break up wave slap and minimise water drag. The 15 contours (10) run essentially parallel to the length of 16 the tunnel (2) as can be seen from Figure 4. The tunnel 17 (2) may also have transverse steps (11), as can be seen 18 in Figure 5, which further help to control water flow 19 through the hull by deflecting water running along the 20 tunnel (2). 21 22 To illustrate the design of a monohull tunnel, Figure 6 23 shows the underside of the hull with tunnel (2) with 24 cross-sections S1 to S6. Figure 7 shows a hull view 25 along the centre of a single tunnel craft from bow (7) to 26 stern (8) sectioned by S1 to S6. It can be seen from 27 Figure 7 that the bow (7) is shaped to reduce the volume 28 of air and water which enters the tunnels. The bow (7) 29 has a droop nose (13) which sits forward of the tunnel 30 (2) and allows for as much water as possible to be 31 deflected from entering the monohull (1) tunnel (2). It 32 can be seen from Figure 9, which is a cross section 33 through S2, that the tunnel (2) is constricted (14) at 34 the bow end. The droop nose bow (13) is in fact a normal 1 bow where the tunnel (2) entrance or entrances on the 2 forward end of the bow (13) are smaller and nearer the 3 water level than the size and height of the tunnel (2) 4 further after, and this reduces the amount of wetted 5 surface and therefore drag within the tunnel. Cross 6 sectional views through S1 to S6 are shown in Figures 8 7 to 13. 8 9 Inclusion of the tunnel (2) in the monohull (1) creates a 10 wider boat which consequently has an improved stability. 11 The advantage of the present invention lies in the fact 12 that an increased stability can be achieved without 13 significantly increasing the amount of effort needed to 14 push the craft through the water. The monohull (1) 15 provides increased stability without creating addition 16 drag as is the case with previous methods which have been 17 used to stabilise boats which generally consist of 18 increasing the wetted area of the hull (1). The tunnel 19 (2) roof is raised above the water so as to minimize wave 20 slap and reduce wetted surface under calm conditions and 21 with smaller waves. The inclusion of contours in the 22 tunnel (2) help give lift to the monohull (1) at speed 23 and help break up wave slap whilst the inclusion of steps 24 (11) in the tunnel (2) help control water flow and reduce 25 wetted surface. 26 27 Figure 14 is a cross-section of a monohull (13) which has 28 a double tunnel, namely tunnels (15) and (16). The 29 underside of the twin tunneled hull (13) can be seen from 30 Figure 15. The tunnels (15) and (16) are arranged in 31 such a manner to create 3 wetted areas, namely (a), (b) 32 and (c). The tunnels (15) and (16) may have contours 33 (10) similar to the embodiment shown in Figure 3, the 34 contours (10) helping to give lift to the hull (13), 11 1 minimise water drag and break up wave slap. Figures 18 2 and 19 show the double tunnel hull of Figures 14 and 15 3 sectioned into cross sections XS1 at through to XS6 in 4 the direction bow (7) to aft (8).

6 Figures 20 to 25 show the cross sectional view XS1 to XS6 7 in more detail. It can be seen from Figures 20 and 21 8 that from the front that is the bow (7) of the sea craft 9 the tunnels (15) and (16) are partially or near completely covered by virtue of the tunnel (2) entrances 11 being smaller and nearer the water surface than the size 12 and height of the tunnel (2) further aft. This limits 13 the amount of air and water which can enter the tunnels 14 (15) and (16) as seen in Figures 22 to 25, and reduces drag, as the amount of waves and water entering the 16 tunnels (15) and (16) is minimised.

17 18 Where the monohull boat is a motorboat, a motor (17) can 19 be located in the middle section or wetted area (b) of the hull. This can be seen in Figure 26. The tunnels 21 (15) and (16) may also house associated propellers (18).

22 Where more than one motor (17) is used, the motors (17) 23 may be positioned in the outer wetted areas (a) and (c) 24 of the hull as shown in Figure 27 or in all three wetted areas (a), (b) and (c) of the hull as shown in Figure 28.

26 The sea craft of Figure 28 also has hydrofoils (19) 27 located in the tunnels (2) which may act as water scoops 28 and/or exit ports for jet water propulsion.

29 Figures 29 to 35 illustrate a twin tunnel displacement 31 hull in more detail. Figure 29 shows the underside of a 32 twin tunnel displacement hull or motor sailor with 33 transverse cross sections MS1 to MS6, which can also be 34 seen from an alternative angle in Figure 30. The views 12 1 seen from cross sections MS1 to mS6 are shown in Figures 2 31 to 36 travelling from bow (7) to stern (8). Where the 3 twin tunnel hull is a keel boat one or more keels (20) 4 may be included in the monohull as extensions of the 5 tunnels (15) and (16) as seen in Figures 34 and 35 or 6 alternatively, may be centrally fitted (21) such as in 7 Figure 36, wherein the keel (22) may be connected to a 8 motor (17) as shown in Figure 37. 9 10 Figure 38 shows a tunnel hull (1) in a cross-section from 11 bow (7) to stern (8) which has an extending bowsprit 12 housing (22) located within the tunnel (2). Specifically 13 the bow sprit housing is located within the contours of 14 the tunnel (2). Figure 39 shows a section of a hull (1) 15 wall with a step (23) protruding into it. 16 17 As shown in Figure 28, one more tunnels (2) may be used 18 to house a hydrofoil (19). A hydrofoil (19) may extend 19 across the tunnel (2) as shown in Figure 40 or may extend 20 below the hull line as shown in Figure 41. More than one 21 hydrofoil (19) can be incorporated into the underside of 22 the tunnel hull (1), as shown in Figure 42 where two 23 hydrofoils (19) are included across the tunnel (2). 24 25 In an embodiment shown in Figure 44 the tunnel (2) of the 26 hull (1) can be adapted to be a support for a seat (23). 27 The tunnel (2) and contours (10) may also form part of 28 the deck or flooring support. 29 30 A tunnelled hull as described in the present invention is 31 particularly suitable for use as small displacement sea 32 craft such as canoes or kayaks. One common type of canoe 33 is the Canadian Canoe, formerly known as an Indian canoe, 34 which is largely open and without significant deck area 13 1 whilst the commonly known "Eskimo" kayak has a complete 2 deck wherein paddlers sit in "cockpits" cut into the 3 deck. 4 5 These craft are relatively narrow of beam and therefore 6 tend to be unstable. Wider beamed boats give more 7 stability but require more energy to push them through 8 the water. Figure 43 shows the underside of the canoe 9 (2) with a tunnel running from bow (7) to stern (8). The 10 tunnel (2) raises the bottom of the canoe along the 11 length of the tunnel (2) above the water line and also 12 widens the canoe by its own width without significantly 13 increasing drag through the water. In addition to 14 widening the boat the tunnel (2) gives the canoe more 15 grip in the water. A bow (7) or stern (8) view of the 16 tunnel hull canoe can be seen from Figure 46. Figure 45 17 shows a crosssection of a tunnel hull kayak, whilst 18 Figure 47 shows a bow or stern view of the tunnel hull 19 kayak. The tunnel (2) shown in Figures 44 to 47 can be 20 moulded to become part of the seating arrangements of the 21 canoe or kayak. It can be seen from Figures 45 and 47 22 that the tunnel (2) may also be sloped upward at the bow 23 (7) to provide extra lift when meeting oncoming waves. 24 25 In yet another embodiment, the contours (10) of the 26 tunnel (2) can be used to locate a mast (24) and mast 27 foot (25) as shown in Figure 48, or housing (26) for a 28 centre plate/dagger board (27) as shown in Figure 49. 29 The tunnel (2) can also be used as a location for a "Z" 30 drive or drop plate (not shown). 31 32 The advantage of the present invention is that the 33 inclusion of one or more tunnels in the monohull of a 34 displacement, semi-displacement or planing boat increases 14 1 the stability of the boat but does not unduly increase 2 the drag, that is the power required to move the boat 3 through the water. Without the water and air restricting 4 features, such as the constricted bow, and the steps and 5 contours on the surface of the tunnel, the tunnel would 6 create additional drag. As a consequence the boat is 7 infinitely safer, and is less likely to capsize under 8 sudden weight shift. Furthermore, an individual who has 9 fallen into the water will be able to pull themselve back 10 onto the tunnel hull boat without capsizing the boat. 11 The one or more tunnels (2) of the monohulls described in 12 the present invention typically have ropes strung along 13 the tunnel (2) which act as safety lines should the craft 14 overturn. The user will be able to use the ropes to pull 15 his or herself back onto the craft. It will be 16 appreciated that the tunnel (2) forms a type of walkway 17 along the bottom of the craft, which the user can pull 18 his/herself into and shelter out of the water, should the 19 craft overturn. As a result of the increase in stability 20 and safety, canoes or kayaks in the spirit of the present 21 invention are better suited to train learner canoeists 22 than conventional canoes or kayaks, and can also be used 23 in novelty games such as obstacle courses and jousting. 24 25 Further modifications and improvements may be 26 incorporated without departing from the scope of the 27 invention herein intended.

Claims

1 CLAIMS

2 3 1. A monohull boat having a monohull with one or more 4 tunnels, the one or more tunnels having a generally forward to aft orientation, wherein the one or more 6 tunnels define a dry region located above the 7 surface of the water, and wherein the monohull has 8 means for reducing drag.

9

2. A monohull boat is claimed in Claim 1, wherein the 11 drag reducing means restricts water flow into the 12 one or more tunnels.

13 14

3. A monohull boat as claimed in any one of the preceding Claims, wherein the drag reducing means is 16 a constricted bow.

17 18

4. A monohull boat as claimed in Claim 3 wherein the 19 entrance of the one or more tunnels has a reduced height and width relative to the height and width of 21 the tunnel further aft.

22 23

5. A monohull boat as claimed in any of the preceding 24 Claims wherein the drag reducing means is provided by virtue of the one or more tunnels having a width 26 which is less than 55% of the average width of the 27 monohull.

28 29

6. A monohull boat as claimed in any one of the preceding Claims, wherein the drag reducing means is 31 provided by virtue of the one or more tunnels having 32 a surface which is adapted to deflect water.

33 16 1

7. A monohull boat as claimed in Claim 6 wherein the 2 surface of the one or more tunnels is contoured.

3 4

8. A monohull boat as claimed in Claim 6 wherein the surface of the one or more tunnels comprises steps.

6 7

9. A monohull boat as claimed in any one of the 8 preceding Claims wherein the monohull has a droop 9 nose bow.

11

10. A monohull boat as claimed in any one of the 12 preceding Claims wherein the one or more tunnels 13 form seating in the monohull boat.

14

11. A monohull boat as claimed in any one of the 16 preceding Claims wherein the one or more tunnels 17 form a housing for an extending bowsprit.

18 19

12. A monohull boat as claimed in any one of the preceding Claims wherein the tunnel forms part of 21 the deck or flooring support.

22 23

13. A monohull boat as claimed in any one of the 24 preceding Claims wherein the monohull boat has one or more keels.

26 27

14. A monohull boat as claimed in Claim 13 wherein the 28 keels are an extension from the sides of the tunnel.

29

15. A monohull boat as claimed in any one of the 31 preceding Claims, wherein the contours in the one or 32 more tunnels form casing and support for centre 33 plates, drop plates, drop keels or dagger boards.

34 17 1

16. A monohull boat as claimed in any one of the 2 preceding Claims wherein the one or more tunnels 3 house a hydrofoil.

4

17. A monohull boat as claimed in Claim 16 wherein the 6 hydrofoil acts as a water scoop and exit port for 7 water jet propulsion.

8 9

18. A monohull boat as claimed in any one of the preceding Claims wherein the one or more tunnels 11 house a spinnaker or gennaker.

12 13

19. A monohull boat as claimed in any one of the 14 preceding Claims wherein the one or more tunnels house propellers.

16 17

20. A monohull boat as claimed in any one of the 18 precerding Claims wherein the one or more tunnels 19 have ropes which act as safety lines in the event of the monohull boat overturning.

21 22

21. A monohull boat as claimed in any one of the 23 preceding Claims wherein the contours in one or more 24 tunnels form casing and support for a mast foot and mast.

26 27

22. A monohull boat as claimed in any one of the 28 preceding Claims wherein the one or more tunnels 29 provides a location for a "Z" drive.

31

23. A monohull boat as claimed in any one of the 32 preceding Claims wherein the one or more tunnels 33 house an outboard engine.

34 18 1

24. A monohull boat as claimed in any one of the 2 preceding Claims wherein the monohull boat is a 3 canoe.

4

25. A monohull boat as claimed in any one of the 6 preceding Claims wherein the monohull boat is an 7 inflatable boat.

8 9

26. A monohull boat as claimed in any one of the preceding Claims wherein the monohull boat is a 11 tender.

12 13

27. A monohull boat as claimed in any one of the 14 preceding Claims wherein the monohull boat is a sailing dinghy.

16 17

28. A monohull boat as claimed in any one of the 18 preceding Claims wherein the monohull boat is a 19 rowing boat.

21

29. A monohull boat as claimed in any one of the 22 preceding Claims wherein the monohull boat is an 23 inboard or outboard motor powered boat.

24

30. A monohull boat as claimed in any one of the 26 preceding Claims wherein the monohull boat is a 27 planing hull.

28 29

31. A monohull boat as claimed in any one of the preceding Claims wherein the monohull boat is a 31 kayak.

32 19 1

32. A monohull boat as claimed in any one of the 2 preceding Claims wherein the monohull boat is a 3 punt.

4

33. A monohull boat as claimed in any one of the 6 preceding Claims wherein the monohull boat is a 7 speedboat.

8 9

34. A monohull boat as claimed in any one of the preceding Claims, wherein the monohull boat is a 11 yacht.

12 13

35. A monohull boat as claimed in any one of the 14 preceding Claims, wherein the monohull boat is a rigid inflatable boat.

16 17

36. A monohull boat as claimed in any one of the 18 preceding Claims, wherein the monohull boat is a 19 yacht.

21

37. A monohull boat as claimed in any one of the 22 preceding Claims, wherein the monohull boat is 23 powered by kite.

24

38. A monohull boat as claimed in any one of the 26 preceding Claims, wherein the monohull boat is 27 powered by a water jet.

28 29

39. A monohull boat as claimed in any one of the preceding Claims, wherein the monohull boat is 31 powered by sail.

32 1

40. A monohull boat as claimed in any one of the 2 preceding Claims wherein the monohull boat has a 3 combination of or more than one means of propulsion.

4

41. A monohull boat as described herein with reference 6 to Figures 1 to 49 of the accompanying drawings.

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