"IMPROVEMENTS IN WATERCRAFT"

FIELD OF INVENTION

The invention relates to improvements in watercraft particularly waka (the Pacific term for a canoe).

BACKGROUND

Waka are the traditional watercraft of Pacific peoples and comprise a canoe-like hull, ^• and often supported by a float attached to one side of the canoe hull by outriggers. Traditionally in Pacific waka the base hull part is carved from a tree trunk and parts are attached to the base hull part on either side to increase the depth of the hull and form the finished hull.

SUMMARY OF INVENTION The invention provides improvements relating to waka which in one form enable greater flexibility in the use of waka for recreational purposes, and which in another form provide waka formed of a lightweight synthetic material with performance or handling more similar to that of a traditional wooden hulled waka.

In a first aspect of the invention comprises a multi-hulled watercraft comprising: a plurality of first watercraft, each comprising: a hull formed primarily of a lightweight synthetic material, outriggers having a first end removably attached to one side of said hull, a float removably attached to a second end of said outriggers opposite said first end, and said multi-hulled watercraft comprising: a hull of at least two of said first watercraft interconnected by said outriggers of said first watercraft attached between said hulls to extend between and couple said hulls together to form said multi-hulled watercraft, said outriggers being removable to reform with said floats of said plurality of first watercraft. Preferably, said hulls are of a similar size.

Preferably, at least two outriggers of similar length are attached between said hulls to extend between and couple said hulls together.

Preferably, at least four outriggers are of the same length and are attached between said hulls to extend between and couple said hulls together, two of said outriggers being removable to

reform with said float of one of said plurality of fkst watercraft, and two other of said outriggers being removable to reform with said float of another of said plurality of first watercraft.

Preferably, each of said floats are of the same size.

Preferably, a bridge component is removably attached to extend between said outriggers of said multi-hulled watercraft.

Preferably, said multi-hulled watercraft comprises a first bridge component extending between a first two outriggers and a second bridge component extending between a second two outriggers of said multi-hulled watercraft.

Preferably, said first and second bridge components are of a similar length. Preferably, said plurality of first watercraft include at least one sail and a mast or boom component at a leading edge of the sail and having a fitting to which the foot of the mast or boom component couples for attachment to a corresponding fitting on a forward end of said bridge component or otherwise on said outrigger.

Preferably, said mast or boom component of said sail of each of said first watercraft are adapted to couple to one or more of said fittings on said bridge components, or on said outriggers connecting said hulls, such that said sail of each of said first watercraft may be positioned in line lengthwise of said multi-hulled watercraft to provide two sails for said multi- hulled watercraft.

Preferably, said hulls each comprise an outer shell and an inner shell extending across the interior of and within said outer shell wherein said inner shell defines a floor within said outer sheU.

Preferably, a buoyancy tank is provided in a space between said outer and said inner shell.

Preferably, a drainable ballast tank is provided in said space between said outer and said inner shell of each of said hulls.

Preferably, said drainable ballast tank includes a closure that is slidably engaged within a closable port formed as part of said drainable ballast tank such that in a closed position said closure is flush with the portion of said outer shell forming the bottom of said drainable ballast tank and flush with the portion of said inner shell directly above said drainable ballast tank. Preferably, said closure is adapted to slide in a substantially vertical direction to allow water to flow into or drain from said drainable ballast tank whilst allowing air to escape from said drainable ballast tank.

Preferably, at least one of said first watercraft includes a skeg housing and having a skeg is pivotally mounted within said skeg housing in a position aft of said closable port.

Preferably, said skeg is held in a raised or a lowered position by a spring and keeper mechanism shaped such that said skeg will retract into said skeg housing if said skeg contacts a solid object.

Preferably, said skeg housing is moulded into said drainable ballast tank behind said closable port.

Preferably, at least one of said plurality of first watercraft includes a propulsion system releasably attached to one said of said hulls and is driven by a power source releasably attached within said hull.

Preferably, said propulsion system is a rim drive propulsor enclosed within a lightweight housing.

Preferably, said housing includes a non-slip surface locatable against said hull in a position such that the draft of said multi-hulled watercraft remains substantially unchanged. Preferably, said multi-hulled watercraft includes two hulls of similar size.

In a second aspect the invention consists in a watercraft comprising: a canoe-like hull having a prow at either end, said hull including: an outer shell formed primarily of a lightweight synthetic material, outriggers having a first end removably attached to one side of said hull, a float removably attached to the second end of said outriggers opposite said first end, and wherein said outer shell includes a ballast tank in said hull, said ballast tank including a closure that is slidably engaged within a closable port formed as part of said ballast tank for filling and draining said ballast tank with water through a bottom part of the outer shell of the hull.

Preferably, said closure is adapted to slide in a substantially vertical direction to allow water to flow into or drain from said ballast tank whilst allowing air to escape from drainable ballast tank.

Preferably, said hull also includes an inner shell extending across the interior of and within said outer shell wherein said inner shell defines a floor within said outer shell.

Preferably, a buoyancy tank is provided in a space between said inner and said outer shell.

Preferably, said ballast tank is provided in a space between said outer and said inner shell.

Preferably, said outriggers are of similar length and have a bridge component removably attached to said outriggers.

- A -

Preferably, said watercraft includes a sail and a mast or boom component at a leading edge of said sail and having a fitting to which the foot of said mast or boom component couples for attachment to a corresponding fitting on a forward end of said bridge component or on a forward-most outrigger when said bridge component is not attached to said outriggers. Preferably, said watercraft includes a skeg housing moulded into said ballast tank behind said closable port in a position aft of said closable port and having a skeg is pivotally mounted within said skeg housing.

Preferably, said skeg is held in a raised or a lowered position by a spring-loaded keeper and is shaped such that said skeg is adapted to retract into said skeg housing if said skeg contacts a solid object.

Preferably, said watercraft includes a propulsion system releasably attached to said hull and driven by a power source releasably attached within said hull.

Preferably, said propulsion system is a rim drive propulsor enclosed within a lightweight housing having a non-slip surface locatable against said hull in a position such that the draft of said watercraft remains substantially unchanged.

In a third aspect the invention consists in a waka comprising: a canoe-like hull having a prow at either end, said hull including: an outer shell formed primarily of a lightweight synthetic material, an inner shell part formed primarily of a lightweight synthetic material which extends across the interior of and within said outer shell, outriggers having a first end removably attached to one side of said hull, a float removably attached to the second end of said outriggers opposite said first end, and a ballast tank formed in a space between said outer and said inner shell wherein said ballast tank includes a closure that is slidably engaged within a closable port formed as port of said ballast tank for filling and draining said ballast tank with water through a bottom part of the outer shell of said hull.

Preferably, said closure is adapted to slide in a substantially vertical direction to allow water to flow into or drain from said ballast tank whilst allowing air to escape from drainable ballast tank.

Preferably, said inner shell defines a floor within said outer shell and a buoyancy tank is provided in a space between said inner and said outer shell.

Preferably, said outriggers are of similar length and have a bridge component removably attached to said outriggers.

Preferably, said waka includes a sail and a mast or boom component at a leading edge of said sail and having a fitting to which the foot of said mast or boom component couples for attachment to a corresponding fitting on a forward end of said bridge component or on a forward-most outrigger when said bridge component is not attached to said outriggers. Preferably, said waka includes a skeg housing moulded into said ballast tank behind said closable port having a skeg pivotally mounted within said skeg housing in a position aft of said closable port.

Preferably, said skeg is held in a raised or a lowered position by a spring-loaded keeper and is shaped such that said skeg is adapted to retract into said skeg housing if said skeg contacts a solid object.

Preferably, said waka includes a propulsion system releasably attached to said hull and driven by a power source releasably attached within said hull.

Preferably, said propulsion system is a rim drive propulsor enclosed within a lightweight housing and said housing includes a non-slip surface that locates against said hull in a position such that the draft of said multi-hulled watercraft remains substantially unchanged.

To those skilled in the art to which the invention relates, many changes in construction and widely differing embodiments and applications of the invention will suggest themselves without departing from the scope of the invention as defined in the appended claims. The disclosures and the descriptions herein are purely ϋlustrative and are not intended to be in any sense limiting.

The term 'outrigger' refers to a part of a boat's rigging that is rigid and extends beyond the side or gunwhale of a boat that is used to provide lateral support to stabilise the main hull. The outrigger is formed from one or more riggers to which a float is attached to provide the desired stability.

The term 'comprising' as used in this specification and claims means 'consisting at least in part of, that is to say when interpreting statements in this specification and claims which include that term, the features, prefaced by that term in each statement, all need to be present but other features can also be present.

The invention consists in the foregoing and also envisages constructions of which the following gives examples only.

BRIEF DESCRIPTION OF THE FIGURES

The present invention will now be described with reference to the accompanying drawings in which:

Figure 1 is a view from one side of a preferred embodiment waka with an outrigger and sail,

Figute 2 is a view from one side of the waka of Figure 1 with the sail removed,

Figure 3 is a plan view of the waka of Figure 1 with the sail removed,

Figure 4 is a plan view of the hulls of two identical waka as shown in Figures 1 to 3, with the outriggers removed and the spar components of the two waka used to couple the two hulls together to form a two hulled craft,

Figure 5 is a view from one side of the two hulled craft of Figure 4,

Figure 6 is a view one from one side of the two hulled craft of Figures 4 and 5 with the sails of the two individual waka fitted to the two hulled craft,

Figure 7 is a transverse cross-section view through the hull of the preferred embodiment waka,

Figures 8A to 8C show individually the outer shell component, inner shell component, and ballast tank-forming component respectively of the preferred embodiment waka hull of Figure 7,

Figure 9 is a side view of the preferred embodiment waka hull of Figures 7 & 8 showing the components of the Figures 8A to 8C fitted together to form the finished hull,

Figure 10 is a cross section view of bung housing and bung mounted in the hull of the preferred embodiment waka,

Figure 11 is a transverse cross-section view through the hull of Figure 7 with a propulsion system attached, Figure 12 is a cross sectional plan view of the propulsion system of Figure 11,

Figure 13 is an elevational view of the propulsion system of Figure 12,

Figure 14 is a view from one side of the hull of Figure 7 showing the propulsion system and the skeg.

Figure 15 is a cross sectional view from a portion on the hull showing the skeg attachment of Figure 14, and

Figure 16 is a cross sectional view of spring keeper mechanism.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Figutes 1 to 3 show a preferred embodiment waka. The waka comprises a hull 1 formed of a modern lightweight synthetic material such as fibreglass or a plastics material. The hull is substantially lighter than a similarly sized traditionally formed wooden hull. It is not intended to exclude a hull that may be formed of a light weight strip plank or plywood construction, typically with a fibreglass outer layer. The hull has a prow at either end so that the hull is canoe-like in shape. Optionally the hull may also have an upright stern and/or prow post which may be decorative if desired. The hull has a hollow interior so that occupants may sit in and paddle the waka or sail the waka. The waka has a float 2 which is attached to the hull on one side by outriggers 3, as will be referred to further. In the preferred form a bridge component 4 bridges the two outriggers 3 and is removably fixed to each of the outriggers 3 at 4a.

Preferably the waka is provided with a sail 5 supported by booms 6 as shown in Figure 1, optionally the sail 5 is supported by a short mast in an alternative configuration. The lower ends of at least one of the boom components 6 (or alternatively of a mast) sits in or is coupled to a fitting or are lashed together at the leading end of the bridge component 4 or, where the bridge component 4 is not present, in or on the forward-most outrigger 3. The sail 5 and booms 6 are supported by stays and control lines 7.

The outriggers 3 are attached to the hull 1 and float 2, and where provided the bridge 4 is fixed to the outriggers 3, by a suitable fixing system which enables the waka to be readily disassembled. In the preferred form the waka may be disassembled without the use of tools. The waka may preferably be disassembled to individual components being the hull 1, float 2, outriggers 3, and bridge 4. A pair of similar waka may be used to form a single twin-huUed craft, as shown in Figures 4 to 6. The two outriggers 3 from each individual waka are used to couple the two hulls 1 together, so that the two hulls are coupled by four outriggers 3 as particularly shown in Figure 4. The outriggers 3 are designed so that they are symmetrical about a transverse axis through approximately the mid point of each outrigger. The floats 2 are designed so that the connection points 2a of the floats at which the outriggers 3 connect to the floats 2 are at approximately the same height when the waka and float are floating, as the points at which the outrigger 3 connect to the hull of the waka. Alternatively, the connection points 2a may be lower or higher.

The outrigger may be fastened to the hull(s) and float(s) by for example webbing straps which may optionally include a ratchet fastener for tensioning the strap at each fastening point if desired, or by other suitable means.

When two hulls are coupled together as previously described the unused floats 2 may be secured one within each of the main hulls, for transporting the floats and also providing additional emergency buoyancy to each of the hulls.

In a preferred form the sail 5 and booms 6 of each of the two waka may be fitted to the twin hulled waka to provide the twin hulled craft with two sails as shown in Figure 6. When the parts of the pair of waka are re-assembled to form the twin hulled craft, the bridges 4 are fixed between the outriggers 3 so that the end of each of the bridges 4 to which the booms 6 couple is positioned forward-most.

Figures 7 to 9 show a hull of a preferred embodiment waka in more detail. The hull is formed from lightweight synthetic material, so that without ballast the hull may be easily carried by a small number of persons and a small size version of the waka may be carried on the roof rack of a motor vehicle for example. In an alternative embodiment however the hull may be much longer and may be up to 12.2 meters in length for example, but the hull will still be much lighter than a traditionally constructed waka.

The hull has a drainable ballast tank in the bottom of the hull. The hull comprises a closable port through a bottom part of the exterior shell of the hull into the ballast tank. The ballast port is closable by a cap or plug or bung in a suitable form. Prior to use of the waka the hull is sat in water, at the edge of the sea or lake for example, so that water will flood upwardly through the ballast port in the bottom part of the hull and fill the ballast tank. A similar port is provided in an upper part of the ballast tank accessible from the interior of the waka, which is also opened to enable air to escape from the ballast tank as the ballast tank fills with water from below. Once the ballast tank is flooded with water, the ports into the ballast tank are closed and the waka may be used. The weight of the water in the ballast tank causes the waka to have a ride similar to a traditional wooden waka. As the hull of the waka is formed of a lightweight material it may be easily transported when the ballast tank is empty. For example, the waka will ride through small waves with movement like that of a traditional heavier waka , rather than ride up and down over the top of small waves.

Referring to Figures 7 to 10, in a preferred form the hull comprises an inner shell part 9 within the outer shell part 10, as shown in Figure 7. Figure 8A is a view of the interior of the outer shell 10 from above and Figure 8B is a view of the inner shell part 9. The inner shell 9 forms a floor of the waka on which occupants kneel or sit. The peripheral edges of the inner shell 9 may be bonded to the interior of the outer shell 10 as indicated at 11 in Figure 7, by

fiberglassing, plastic moulding, adhesive or any other suitable means. The inner shell 9 also forms a buoyancy tank which in the preferred form extends longitudinally of the hull, defined between the inner shell or floor 9 and the outer shell 10. The buoyancy tank may be divided into two parts by a vertical panle extending along the keel line between the inner shell 9 and outer shell 10. The preferred embodiment waka also comprises a part 12 which defines a ballast tank volume 13 which is smaller than the volume of the space 14 between the outer and inner shells of the hull. The ballast tank part 12 has an elongated hour glass-like shape in plan view as shown in Figure 8C and a curved shape in transverse cross-section as shown in Figure 7. As shown in Figure 7 peripheral flange edges 15 of the ballast part 12 are bonded to the interior surface of the outer shell 10 to define between the volume 13 which forms the ballast tank of the waka. A port (not shown) through the bottom of the outer shell 10 of the waka opens into space 13. The inner shell 9 is also fixed to the ballast part 12 along the centre line of the waka as shown. The port which enables air to escape from the interior of the ballast tank passes through the inner shell and also into the space 13

To give the waka hull an appearance similar to that of a traditional waka hull, longitudinally extending parts 17 may be fixed to the exterior and interior surfaces of the hull as shown in Figure 7. Also, the upper edges of the hull may be enlarged, for example by providing elements 18 fixed to the edges of the hull shell as shown. The parts 17 and 18 may be formed of wood or a alternative material such as an lightweight synthetic material. They may be formed so as to be decorative if desired.

Figure 10 is an enlarged cross-section view transversely through approximately the centre part of the hull, showing a preferred form bung arrangement. The bung is indicated at 20 and is slidably moveable in the direction of arrow A in Figure 10 in a bung housing 21 which extends between the outer shell 10 and inner shell 9 and part 12. Ports 22 and 23 are provided in the bung housing 21. The bung has a necked or narrowed centre portion 20a and an enlarged end 20b formed of a soft material such as rubber or a compressible synthetic material. The bung is shown cutaway along its longitudinal axis in Figure 10. The bung is moveable in the direction of arrow A between a closed position shown in hard outline in Figure 10 and an open position shown in phantom outline. When the bung is in the closed position the end 20b of the bung closes the port in the outer shell 10 (to prevent ingress or egress of water from the hull and ballast tank). The top of the bung 20 is flush with the floor 9. When the bung is withdrawn by moving it up to the position shown in phantom outline in Figure 10, water may flow into or drain from the volume 13 which forms the ballast tank. For example when the ballast tank is filling,

water may flow from below the hull into the lower part of the bung housing 21 and through the port 22 into the ballast tank 13. At the same time arc may escape from the ballast tank 13 through the port 23 and through the top of the bung housing. Similarly when the ballast tank is being drained water may flow from the ballast tank through the port 22, and air may enter into the ballast tank through the port 23. The bung is designed such that it cannot be completely removed during use and as such is one preferred form which may be used with a waka of the invention.

Rim Drive Propulsion System When undertaking a long journey for example, it is preferable that the watercraft or waka of the invention is capable of being adapted to have a propulsion system 30 removably attached to the hull 1. Alternatively, in a multi-hulled configuration, the bridge components 4 attached to the outriggers 3 can be used to mount the propulsion system whereby the propulsion system is located at the rear end of the bridge component at the aft end of the watercraft 1. It is envisaged that propulsion is provided by a rim drive propulsor unit 30 powered by an electrical generator system 40, batteries or fuel cell that is connected to the propulsor unit 30 by electrical cables 31 for example. In an alternative configuration, electrical power is transferred from the electrical generation system 40 to the propulsor unit 30 using magnetic induction technology.

The rim drive propulsion unit 30 is preferably removably attached to the outer shell 10 of the waka hull 1 as shown in Figures 11, 12 and 14. The propulsor unit 30 is incorporated within a housing 32 formed from a thermo-moulded plastics type material and having a non-slip surface that contacts the hull 1 and is held in place against the hull 1 using a system of straps 33 such as ratchet type straps or clamps as shown in Figure 13. Alternatively, the propulsor unit 30 can be keyed into the hull 1 using a mechanical joint (not shown) that is moulded into or attached to the hull 1. Hence, the propulsor unit 30 can be located at any position along the outer shell 10. It is also preferable that the propulsor unit 30 is manufactured such mat it has positive buoyancy so that it has little effect on the trim of the hull 1 when attached to the hull 1 and will also float if it is accidentaEy dropped in deep water for example.

The propulsor unit housing 32 includes an intake duct 34 at the forward end of the housing 32 providing a water intake for the propulsor unit 30. The propulsor unit 30 is substantially horizontally disposed within the housing 32 for driving water received through the intake duct 34 toward an outlet nozzle 35 at the rear of the housing 32. The propulsor unit 30 includes and electric drive motor 36 that is powered via electrical power connections 31 to a power generation module 40 removably located on the floor 9 within the hull 1 of the watercraft.

With reference to Figures 12 and 13, the propulsor housing 32 is a tube-like structure having a central bore extending through the housing 32 through which water is drawn in and expelled. The electric drive motor 36 has a stator 37 that includes an array of windings incorporated around a section of the internal circumference of the housing 32. A number of inwardly directed propeller blades 38 are attached to a rim or hub 39 located in the housing 32 such that the hub 39 is in alignment with the stator windings 37. Attached to the external periphery of the hub 39 are a number of permanent magnets 41 located in a small gap 42 between the hub 39 and the stator windings 37 to form a motor rotor 43. Hence, the rotor 43 is in horizontal alignment with the tubular inner surface of the propulsor housing 32. Covering the water intake 34 is a grill 44 used to stop larger objects from entering the housing 32 and potentially damaging the propeller blades 38. Water is discharged at the rear of the housing 32 that incorporates a nozzle 35 used to control the direction of the waterjet out of the housing 32. The nozzle 35 includes a mechanism for fixed adjustment of the nozzle 35 to allow the directional motion of the watercraft to be trimmed in order to hold the watercraft on a steady course. Alternatively, the nozzle 35 can be used to steer the watercraft by having the nozzle 35 pivotably attached to the interior of the housing 32 about the vertical axis, provided by a swivel joint, ball joint type assembly or other known mechanical type joint assembly (not shown) that is integral with the nozzle 35 . The direction or pivoting of the nozzle 35 is connected to a mechanical steering device (not shown) via a cable to enable the pitch of the nozzle 35 to be controlled to provide a steerable watercraft.

The rim drive propulsor 30 is a small portable and lightweight propulsion device that can be easily and simply attached to the hull 1 of the watercraft such that the housing 32 is submerged just below the waterline. The propulsor unit 30 is mountable on either side of the watercraft keel line without increasing the draft of the watercraft enabling the watercraft to be driven in relatively shallow waters. Furthermore, the propulsion system 30 incorporates few moving parts and is cooled and lubricated by water thereby providing a simple, easily maintained propulsion system for the watercraft.

Power Source The power source such as a generator 40 is enclosed in a protective casing and preferably has built-in positive buoyancy. It is preferable that the power source 40 is removably secured centrally within and about the mid-line of the hull 1 on the floor 9 of the watercraft. Placing the power source 40 in this position as shown in Figure 14 will ensure the watercraft maintains a low centre of gravity. The power source 40 preferably includes a fuel source enclosed within the protective casing. Alternatively, the fuel source is enclosed within a

waterproof housing located in close proximity to the power source 40 and is releasably attached to the floor 9 of the watercraft. Fuel is provided to the power source 40 via a fuel line (not shown) connected between the fuel source and the power source 40. Both the power source 40 and fuel source (if separate) have access ports in their housings to enable maintenance to be undertaken and/ or to enable fuel to be added to the fuel source.

As mentioned previously, the power source 40 is electrically connected to the propulsor unit 30 by one or more electrical cables 31. The power source 40 may be used to power the propulsor 30 and other utilities simultaneously. Alternatively, when not being used to drive the propulsor unit 30, it may power utilities such as a refrigeration unit whilst on the water for example. Due to the portable nature of the power source 40, the power source 40 can be removed from the watercraft and to provide power to one of a number of different systems including but not limited to a refrigeration unit, communications equipment, navigation equipment, ship type lighting, water treatment equipment. Hence, the power source 40 is capable of being mechanically and electrically interfaced to one or more of these additional systems.

Retractable Skeg

With reference to Figure 14 and 15 the watercraft hull 1 can be adapted to include a housing 50 for a skeg 51 that is moulded into the water-ballast tank 13 behind the closable port or housing 21 that is used for filling and draining the ballast tank 13. The skeg 51 is pivotably attached just aft of the closable port 21. This arrangement enables the skeg 51 pivot joint to be accessed through the openings 22, 23 in the hull 1, when the closable port mechanism 21 is removed, to enable the skeg 51 to be maintained and/ or replaced.

The skeg 51 is held in either a raised or lowered position by a spring and keeper mechanism 60 as shown in Figure 16 that is used to lock the skeg 51 in position. The spring and keeper mechanism 60 includes a spring 60 made preferably of stainless steel, that has a lever 62 attached approximately mid-way along the spring 61. The lever 62 is pivtoably connected in close proximity to the outer shell 10 enabling the spring 61 to be biased towards a keeper 63 attached to the upper surface of the skeg housing 50. The end of the keeper 63 includes a bevelled surface 64 towards the end of the keeper 63 in close proximity to the spring 61 enabling the curved upper end 65 of the spring 61 to slide across the bevelled surface 64 to engage the keeper 63. In this position, the skeg 51 is held in the raised position within the skeg housing 50. When the lever 62 is depressed, the spring 61 is pivoted away from the keeper 63 enabling the skeg 51 to lower. With the skeg 51 in the lowered position, the keeper bevelled surface 64-locates on the lower internal surface 67 of the skeg housing 50 enabling the bottom curved end 66 of the

spring 61 to slide across the keeper bevelled surface 64 to retain the skeg 51 in the lowered position. The lowered skeg position is illustrated in Figure 16 by as a dotted outline.

To raise the skeg 51 into the skeg housing 50, the lever 62 is depressed enabling the bottom curved end 66 of the spring 61 to disengage the bevelled surface 64 enabling the skeg 51 to retract into the skeg housing 50. Furthermore, in the event that the watercraft 1 runs aground or hits a submerged object for example, the spring 61 will deflect due to the curvature of the spring 61 causing the bottom end 66 of the spring to disengage the bevelled surface 64 of the keeper 63 allowing the skeg 51 to retract into the skeg housing 50 thereby protecting the skeg 51 from potential damage. The watercraft has been constructed such that the outriggers 3, floats 2, bridge components 4 and propulsion systems 30 are all capable of being releasably attached to the watercraft hull 1. As such, the watercraft provides a versatile structure that can be used for a range of purposes. As an example, when setting up camp on a remote island, the outriggers 3 and bridge components 4 can be used to form a shelter structure to support a fabric covering. The power source 40 can be used to provide lighting around a camp and/ or provide power for cooking and communications equipment.

The forgoing describes the invention including preferred embodiments thereof. Alterations and modifications as will be obvious to those skilled in the art are intended to be incorporated in the scope hereof.