The present invention relates to a marine propulsion planing boat, of the type in which a lift is generated, which is caused by the push provided by the marine propulsion, which reduces to the minimum the surfaces of the boat wet by water.

The invention then is useful to be applied to boats with a stiff underwater body, such as for example motorboats and rubber dinghies which, when the boat is not navigating, have the underwater body at least partially immersed.

Here and hereinafter, under planing boat a water vehicle is meant which remains sustained by the sea surface in any step of its navigation.

Here and hereinafter, under "marine propulsion" a propulsion form is meant which provides one or more propelling organs, such as propellers or jet devices, which interact with water, in immersion or in case near the sea surface.

Here and hereinafter, under "navigation" the boat proceeding at a speed which is determined by the push of the marine propulsion is meant, which can be suitably selected and adjusted from a control position, based upon the operating needs of the boat, and even upon the contingent needs, such as the state of wind and sea.

In particular, the invention refers to planing boats wherein the lift is determined, apart from by the shape of the underwater body, by the presence of hydrofoils, which comprise wing profiles immersed in water allowing, when the speed increases, to create a vertical push on the boat, by contrasting the gravity and thus allowing the boat to raise the hull and to remove the fluid resistance .

In the above-described configuration, the boat continues to be sustained by the marine surface whereon the wing profiles slide which, in the present invention, determine at least a pair of contact points with water, points which are symmetric with respect to the centre line of the boat.

Boats are known, generally called hydroplanes, which substantially have wings projecting from the underwater body, constituting the single portion in contact with the water surface during high-speed navigation.

This navigation mode with the underwater body outside the water or with a minimum portion in water has the main purpose of reducing the consumption of fuel or propulsive energy in general. However, to reach the speed required to raise from water, both in hydroplanes and in boats with stiff keels, the consumptions and costs related to the propulsive energy remain high, as well as the environmental pollution they generate.

Moreover, the hydroplanes have no good low-speed performances, since the wings in water determine a drift effect, not requested by the manoeuvres, and a greater friction with water.

Besides, the boats with the stiff underwater body, having a shape suitable to raise, are reliable and flexible, but the performances in speed and propulsive effectiveness cannot compete with those of a hydroplane.

An example of boat, based upon the hydroplane model and thought to further optimize the reduction in consumptions 2 even at high speeds is reported in US patent No. US 3,157,146 A of 1964, illustrating a boat equipped with a single ski below the hull and a high and fixed wing, raised with respect to the deck. The presence of the ski, analogous to that of the hydroplanes and of the high wing allow the boat to navigate at high speeds in planing configuration, that is with the hull raised with respect to the water surface or just tangent. To be apt to navigate under these conditions, the boat even provides a propulsive element immersed at a depth so that the propeller, even with the boat in planing configuration remains below the free surface of water.

Disadvantageously, this type of boat has several limits: the wing is static, and this creates both problems of overall dimensions in the transportation and mooring steps, and safety problems in case of quick variations in weather and sea conditions, the mono-ski makes people to think to an easy propension to roll or better to the lateral skidding of the boat when in the planing step, with possible very dangerous consequences.

A more recent document, dating back to 2018, is Dutch patent No. NL 1,104,936 B1. In this case a motorboat is claimed equipped with those which can consider the modern version of "skis" of hydroplane and that is of hydrofoils. The hydrofoils are nothing more than suitably shaped fins, equipped with wing profiles (foil). They perform the same role of a wing in air but in water.

In fact, their shape is so that once reached a determined effective speed, the foils generate lift and raise the boat from water. In this document even the propulsive elements are connected to the stern elements which cooperate to the formation of the lift and guarantee to 3 keep the propellers immersed even in the planing step of the boat.

In this case, the boat comprises fixed hydrofoils and fixed propulsive elements at a determined depth. Even in this case the problem of overall dimensions during transportation and mooring persists, without counting that having fixed appendixes the boat is optimized only for determined planing speeds. On the contrary, at low speeds the consumptions will be greater than equivalent boats with stiff keel but without hydrofoils. Moreover, one will have difficulties in mooring in presence of shallow water.

Another category of hybrid vehicles among the marine ones and the aeronautical ones having the purpose of optimizing navigation and consumptions find embodiment examples in Chinese patent applications No. CN 108,128,453 A (CN'453), No. CN 109,383,796 A (CN'796) and in German patent No. DE 101,08,596 Cl.

In CN'453 a drone is shown having a high wing coated with solar panels, two pairs of hydrofoils, the front ones thereof have a shape analogous to the skates of seaplanes rather than a wing profile. The vehicle is equipped only with propulsion in air, with propellers arranged above the high wing and it provides that the wing is re- foldable for the transportation and mooring steps. The hydrofoils or skates are all fixed.

In CN'796 a vehicle is shown which could be considered more similar to a seaplane, but without skates. The new components of this invention lie in the fact that it provides telescopically retractile high wings, still with the purpose of reducing the overall dimension during transportation and mooring and which has a propeller with 4 a sustaining arm with fixed length, but rotating around an axis which allows it to work both in air and in water.

At last, German patent No. DE 101,08,596 Cl relates to a vehicle like a hovercraft but equipped with foldable wings .

Another vehicle, which can be listed in the class of vehicles like the present invention, is shown in US patent No. 2,980,047 A, relating to a submarine vehicle, equipped with a system of hydrofoils which when it is out of the water allow it to navigate in planing configuration and then by reducing the consumptions.

The technical problem underlying the present invention is to provide a marine propulsion planing boat, capable to overcome the drawbacks described with reference to the known art.

Such problem is solved by a marine propulsion planing boat as specified above, and as defined in the enclosed independent claim. Additional details of the invention are defined in the dependent claims.

The main advantage of the marine propulsion planing boat is the capability of planing even at low speeds by reducing the consumptions of propulsive energy by adapting to different weather and sea conditions while falling within the shape of traditional planing boat, so it can be docked and trailered.

The concept underlying the present invention is to be able to raise firmly as much as possible a boat from the water as far as the limit allowing the effective action of the propulsion organ only which remains immersed with respect to the water surface, coherently with the assumption that, the lower the friction of the boat in 5 water, the less energy is needed for the propulsion at the same speed.

To this purpose, the boat according to the present invention comprises a hull with underwater body and deck, and a roof structure which is provided with a cover raised with respect to the deck. This cover defines a container including a plurality of wing elements which are interconnected to each other with a telescopic correlation; they have a respective profile with cross sections having decreasing sizes, suitable to assume a contracted configuration wherein the wing elements are arranged inside one another within the cover.

Moreover, the propulsion system of the boat, which is connected to its hull, comprises at least a propulsive element which is apt to be immersed in water, and a device for positioning said at least a propulsive element at a variable depth with respect to the marine surface.

The boat further comprises, on the underwater body, at least a hydrofoil which in turn has in particular a pair of wing profiles which are capable of determining a corresponding pair of contact points of the boat with the marine surface, symmetrical with respect to the centre line of the boat.

The wing profiles of the hydrofoil then are arranged to raise the boat thanks to the lift generated by the navigation .

The wing profiles, thanks to respective masts or shafts capable of varying their respective projection from the underwater body, are retractable in the profile of the underwater body, and they are movable by projecting downwards in an extended configuration, wherein they are 6 at a predetermined operative distance from the surface of the underwater body.

In this extended configuration, the wing elements can assume an expanded configuration, starting from said contracted configuration, by projecting laterally from the cover and from the profile of the hull in two opposite directions, thus forming a high wing, with adjustable width, which can determine an additional lift which sums to the lift determined by the hydrofoil in extended configuration.

The present invention will be described hereinafter according to a preferred embodiment example thereof, provided by way of example and not with limitative purposes with reference to the enclosed drawings wherein:

* figure 1 shows a front view of the boat with the extensions in air in expanded configuration according to the invention;

* figure 2 shows a perspective view of the boat, the wing comprising the stabilizing flaps, according to the invention;

* figure 3 shows a lateral view of the boat with the hydrofoils in use position, according to the invention;

* figure 4 shows a perspective view of the boat with the hydrofoils in use position and the extensions in air retracted, according to the invention;

* figure 5 shows a front view of the boat with the hydrofoils in use position and the extensions in air retracted, according to the invention;

* figure 6 shows a lateral view of the boat with the hydrofoils in retracted configuration, according to the invention;

* figure 7 shows a front view of the boat with the 7 hydrofoils in retracted configuration and the extensions in air retracted, according to the invention;

* figure 8 shows a perspective view of the boat with the hydrofoils in extracted position of not use, since emersed depending upon the lift of the extensions in air and two propulsive elements on the stern hydrofoils, according to the invention;

* figure 9 shows a front view of the boat with the hydrofoils in extracted position of not use since emersed depending upon the lift of the extensions in air and two propulsive elements under the stern hydrofoils, according to the invention;

* figure 10 shows a front view of the boat with the extensions in air in expanded configuration with four propulsive elements under retracted hydrofoils, according to the invention;

* figure 11 shows a perspective view of the boat with the extensions in air in retracted configuration with four propulsive elements under the retracted hydrofoils;

* figure 12 shows a front view of the boat with the extensions in air in retracted configuration with four propulsive elements under the retracted hydrofoils;

* figure 13 shows a lateral view of the boat with four propulsive elements under the retracted hydrofoils according to the invention;

* figure 14 shows a top view of the boat with the extensions in air in retracted configuration, according to the invention;

* figure 15 shows a front view of the boat with the extensions in air in expanded configuration, the four hydrofoils being in extracted use position since emersed depending upon the lift of the extensions in air and the four propulsive elements under the hydrofoils acting on the water surface; 8 * figure 16 shows a perspective view of the boat with the extensions in air in expanded configuration, the four hydrofoils being in extracted use position since emersed depending upon the lift of the extensions in air and the four propulsive elements under the hydrofoils acting on the water surface;

* figure 17 shows a lateral view of the boat with the extensions in air in expanded configuration, the four hydrofoils being in extracted use position since emersed depending upon the lift of the extensions in air and the four propulsive elements under the hydrofoils acting on the water surface;

* figure 18 shows a top view of the opened-wing boat, according to the invention;

* figure 19 shows a front view of the moving boat, with the extensions in air in an intermediate configuration between the contracted configuration and the expanded configuration, the four hydrofoils being in extracted use position since emersed depending upon the lift of the extensions in air and the four propulsive elements under the hydrofoils acting on the water surface and immersed in proportion to the lift generated by the high wing and by the hydrofoils;

* figure 20 shows a perspective view of the boat according to the configuration of figure 19;

* figure 21 shows a lateral view of the boat according to the configuration of figure 19; and

* figure 22 shows a top view of the partially-opened-wing boat, according to the configuration of figure 19.

With reference to figures, a boat is designated as a whole with 1; it comprises a hull 2 having an underwater body N, an opened deck 3 and a roof structure 4 which is provided with a covering element 5 arranged on uprights 7 fastened on the deck 3 and projecting vertically upwards. 9 The covering element 5 has a cross section shaped with a wing profile, and it is raised with respect to said deck 3; it comprises one or more extensions 6, in particular a plurality of wing elements 6 interconnected to each other with a telescopic correlation, having a profile with cross-sections having decreasing sizes, suitable to assume a contracted configuration wherein the wing elements 6 are arranged inside one another in said cover 5.

The wing elements 6 are movable between a first contracted configuration (figures 4 and 5), wherein they are incorporated in said cover element 5, and a second expanded configuration (figures 1 and 2), wherein they project laterally beyond the edges of said hull 2 by forming a high wing 9, that is a wing mounted above the boat 1.

Said high wing 9 has an adjustable width, so that, during navigation, the lift required to assume the planing configuration is determined.

Said wing elements 6 have a cross section shaped like a wing profile similar in the geometrical direction to that of the covering element 5.

Preferably, said cover 5 is integral to the boat through a connecting apparatus which constraints it both to the underwater body N, and to the deck. For example, the anchoring to the underwater body N takes place through the fastening of the uprights 7 having metal plates integral to the ordinates composing the underwater body N, so that it is not just the deck which opposes to the lift generated by the cover 5 or by the high wing 9 in expanded configuration or in an intermediate configuration .

Said boat 1 even comprises a marine propulsion system 11 connected to said hull 2, comprising at least a propulsive element 12, apt to be immersed in water, and a

- 10 device 25 for positioning said at least a propulsive element 12 at a variable depth with respect to the marine surface. The marine propulsion system 11 is acting in water with marine propellers or water-jet propulsors, consisting of a set of portions, there among one or more motors.

For example, said motors can be thermal motors or electric motors. In both cases, the motors can be of outboard type (figure 3) of the propeller-like type, or alternatively, of the internal type with the transmission with one or more propellers placed below the underwater body.

The marine propulsion system 11 generally comprises at least a propulsive element 12 immersed in water and positionable at a depth so that, when the hull 2 is pushed while planing with respect to the water surface, it remains immersed partially at water level. Examples of propulsive elements 12 are the marine propellers arranged below the underwater body N; alternatively, the propulsive elements can be surface propellers, hydrodynamic-jet propulsion pods, electric propulsors with integrated propellers and so on.

The boat 1 further comprises at least a hydrofoil 20 comprising a pair of marine wings 22 with wing profiles capable of determining at least a pair of contact points of the boat 1 with the marine surface, symmetric with respect to the centre line of the boat, and apt to raise the boat 1 thanks to the generated lift, wherein the marine wings 22 are retractable in the profile of the underwater body N, and are movable in an extended configuration wherein they project from the underwater body N.

Under marine wings 22 wings are meant, with wing profile, which operate in water.

Preferably, the motion of the wing elements 6 movable

- 11 between the contracted and expanded or extended configuration takes place through a device for controlling the extension from the control stations 13 placed on the boat 1. Moreover, it is also possible to expand the wing elements 6 in intermediate configurations depending upon the intensity of wind and wished speed.

Moreover, the boat 1 can include a control unit, connected to said positioning device 25 and to said control device, incorporating a microprocessor and at least a memory comprising a software for controlling the lift. Thanks to said software, the positioning device 25 and the control device adjust respectively the distance of the propulsive element 12 from the underwater body N and the width of the high wing 9 so as to keep, when the hydrofoil 20 is in extended configuration, the propulsive element 12 at the marine surface whatever the navigation speed in a predetermined range is.

Said control unit is provided with accelerometric and positional sensors such as gyroscopes and/or IMU.

The boat 1, the invention relates to, has the advantage, with respect to the solutions existing in the state of art, of comprising two types of carrying elements: those in air, that is the high wing 9, and those in water, that is the hydrofoils 20.

The presence of both these carrying elements, the speed of the boat 1 and of the weather and sea conditions being equal, allows to distribute the loads of the mechanical efforts between the high wing 9 in air and the marine wings 22 of the hydrofoils 20.

From the control stations 13 it is possible to control even the incidence angle of the wing profile of the wing elements 6 through a respective rotation around a rotation axis X (figure 2) arranged longitudinally with respect to the high wing (9), controlled by said control unit .

- 12 Preferably, the adjustment of the incidence angle of the wing profile takes place through one or more actuators, not represented, positioned on the roof structure 4 and connected to the cover 5 near its stern portion.

The possibility of controlling said incidence angle makes the wing 9 adaptable to the most different weather and sea conditions, and at any speed one wishes to maintain.

Advantageously, the adjustment of the incidence angle allows to limit the pitch of the boat 1 and to ease the step of raising from water and of starting the planing, but even the landing step, that is of descending with respect to the planing configuration until immersion of the underwater body N in water.

According to the invention, if the hydrofoils 20 are left inside the underwater body N, the planing step is the one in which, thanks to the lift generated by the high wing 9 at a take-off speed, reached thanks to the propulsive system 11 which acts in water, the boat 1 raises almost completely from water, by leaving only the stern area of the underwater body 8 partially immersed. When, in this configuration, in presence of rough sea, the boat 1 reaches the crest of a wave, thanks to the presence of the wing 9, the boat does not heel between two crests of subsequent waves but it wholly or partially detaches from water by flying or jumping from a wave to the subsequent one.

Due to the lack of propulsion in the flight and jump step, since the propulsive element does not draw in water but it is raised in air, to avoid a violent landing on the water surface, the pitch and inertia upon starting again the planing step, it is possible to vary the incidence angle of the wing 9, by conferring greater lift so as to land on the crest of the subsequent wave more softly than what it would happen with a traditional boat.

Moreover, the control of the incidence angle guarantees

- 13 even a greater safety for the onboard people, by allowing to face quick variations in the wind intensity.

Another advantage of said wing 9 is that it has starboard wing portion 15 and a left portion 16 (figure 1) which can assume incidence angles different to each other, for example by exploiting the differential actuation of the actuators and the torsional elasticity of the covering element 5, so to ease nautical manoeuvres like a tack.

An additional advantage derives from the fact that, according to an embodiment of the invention, the two more external wing elements 6 in expanded configuration, that is the distal end extensions, comprise an output flap 26 (figure 2) suitable to ease nautical manoeuvres such as a tack and to reduce rolling, to contrast the trim variations, due to external causes such as a wave or a sudden wing gust, of the boat 1. Preferably said flap 26 is controlled automatically.

Such automatic control takes place through said control unit provided with accelerometric and positional sensors allowing, through a microprocessor processor, to know both the position and the speed of the hull 2 and of the wing 9, and the stresses thereto they are subjected.

In the preferred version illustrated in the enclosed figures, the wing elements 6 are interconnected to each other with a telescopic correlation, then they can insert inside one another in contracted configuration, and have coaxial wing profiles, with cross section having sizes decreasing from the centre of the boat 1 towards outside; said wing elements 6 then go from the contracted configuration in which they are hierarchically contained inside one another and incorporated inside the covering element 5 acting as external casing, to expanded one, by extending telescopically along the axis X.

In this way, said wing elements 6 extend and contract by moving horizontally, by remaining substantially parallel 14 to the water surface and then providing a lift, proportional to the extension, even during the transition from a configuration to the other one.

Preferably, said wing 9 has a configuration twisted upwards starting from the centre towards the external ends. From the aerodynamic point of view, this allows to obtain the maximum lift in the expanded configuration, and a quicker and more marked reduction in the lift going from the expanded configuration to the contracted one. The twisting of the wing elements 6 can be made compatible with their telescopic insertion inside one another, allowing them a minimum rotation around the axis X.

The expandable telescopic wing elements 6 allow to navigate both traditionally with the wing elements 6 in retracted configuration, the various wing elements 6 being integrated in the covering element 5 of the roof like structure 4, typical of several of the boats of interest for this invention, and to open gradually the wing elements 6 to form the wing 9 with the size useful to make the boat 1 to plane with the existing weather and sea conditions, compatible with such geometry.

Preferably, the telescopic extension takes place with the electromechanical system comprising a telescopic actuator of torsional type or like a belt, placed inside the covering element 5 and the wing elements 6 or with independent multiple telescopic actuators, arranged each one in its own extension 6.

Advantageously, the telescopic nature of the extensions 6 allows to open and close the wing elements 6 in an easy, quick, and controlled manner. In fact, the wing elements 6 are not moved manually but by an electro-mechanical system controlled by the control stations 13.

According to a preferred embodiment of the invention, the covering element 5 is coated on the upper surface with

- 15 photovoltaic panels 17 (figure 7) suitable to feed the electronics and the onboard services, and/or to charge a system of electronic accumulators.

Advantageously, the boat 1, that is its propulsive system, can include electric propulsions 18, comprising an electric motor and a marine propeller in one single casing (figure 9). The electric propulsors 18 can be fed by electric accumulators or directly by said photovoltaic panels 17.

In case, even said wing elements 6 are coated both on the upper and lower surface with photovoltaic panels 17 suitable to feed the onboard electronics and at least an electric propulsive system 18.

The fact of coating the wing elements 6 with photovoltaic panels 17 even on the lower surface, that is the one facing the water, allows to exploit even the reflection of the solar rays produced by the surface of the water itself .

The presence of the photovoltaic panels 17 is advantageous since it contributes to reduce or remove, in case of electric propulsive system, the fuel consumption, by reducing the navigation costs and the generated environmental impact.

Advantageously, the above-illustrated embodiments of the invention guarantee a reduction or removal of the fuel consumption and of the environmental pollution, since the presence of the wing 9 allows to navigate while planing, then while having most part of the underwater body 8 outside the water, starting from lower speeds than those required to the boats without wing 9. Moreover, under planing condition, the water resistance on the hull 2 is much lower and then the possible consumption of fuel or propulsive energy in general are much lower too.

The last described configurations provide the use of the high wing 9 only to make the boat 1 planing, but the

- 16 optimum navigation configurations also provide the use of the hydrofoils 20 in extended configuration with respect to the underwater body N.

Each hydrofoil 20 comprises a shaft 21 projecting from the underwater body N (figure 3) which has a distal tract where the marine wing 22 is positioned.

The hydrofoils 20 can include a front hydrofoil, arranged on the underwater body N near the bow of the boat 1, and a rear hydrofoil, arranged near the stern of the boat 1.

The front hydrofoil eases to raise the bow of the boat 1, thanks to the lift generated by the push applied by the propulsive element 12.

The hydrofoils 20 are movable, that is retractable in a suitable compartment of the underwater body N, or adhering to the profile of the underwater body N.

In this version, the hydrofoils 20, under conditions of not use, are contained or adhering to the underwater body 8 and do not interfere with the sea bottom.

When one navigates by using the hydrofoils 20 in extended configuration the propulsive element 12 can be a marine propeller mounted on a device 25 for positioning the propulsive element 12 at a variable depth with respect to the marine surface, so as to guarantee the draught of the propeller 12 even when the hull 2 is raised by the hydrofoils 20 while planing at a certain distance (figures 4 and 5) with respect to the water surface; in this way, the propeller 12 remains immersed substantially at water level or it navigates near the water surface, in this case without determining a propulsion.

Preferably, said marine propeller 12 is a surface propeller, that is a propeller acting at water level, the blades thereof move by cutting into the sea surface instead of being wholly immersed.

According to a preferred embodiment of the invention, one

- 17 provides to apply a pair of hydrofoils 20 (figures 4 and 5), near the bow, to the planing boats of small cabotage. The pair of hydrofoils 20 is placed symmetrically with respect to the keel line.

In this embodiment, the boat 1 will always have a small portion of underwater body N at stern and the propulsive elements 12 in water.

According to another preferred embodiment of the invention, one provides to apply four hydrofoils 20 to the planing boats of small cabotage, two beyond the centreline and two near the stern. Both pairs of hydrofoils 20 are placed symmetrically with respect to the keel line.

In this embodiment, the boat 1 could raise completely from the water, therefore the propulsive system 11 can include mechanisms for the height variation of the marine propeller of outboard motors or propellers 12 of internal motors, placed below the underwater body N.

Advantageously, these systems adjustable in the planing step of the boat 1 equipped with four hydrofoils 20, adjust the height of the propellers 12 so as to keep them always immersed and not to lose the propulsion required to generate the lift for the wing 9 in air and for the hydrofoils 20.

Alternatively, in case of internal motors, below the marine wing 22 of the hydrofoils 20, at least a propulsive element 12 is positioned, by determining the sequence moving away from the underwater body of: shaft 21, marine wing 22 and propulsive element 12.

Preferably said propulsive element 12 is a surface marine propeller which then moves vertically with the hydrofoils 20 (figure 8) and remains always near the water surface by guaranteeing the propeller draught and then the propulsive effectiveness of the boat 1.

- 18 The hydrofoils 20 of retractable type, completed with control systems, are integrated below the deck plan of the boat 1 so that the marine wing 22 of the hydrofoils 20 integrates in the section of the underneath underwater body N, within a recess called step, suitably arranged at industrial level.

When the boat does not navigate in shallow water one can actuate the coming out, downwards, of the hydrofoils 20. The shaft 21 of the hydrofoils 20 is conceived with a shape so as to adapt in a manner conjugated to the step, that is a guide inside the underwater body N, which locks it to tolerance to compensate for all stresses during navigation .

When the hydrofoils 20 start to provide effective lift, that is the take-off beginning speed, which has to be suitably calculated for each type of boat depending upon the tonnage, the point of centre of gravity, the maximum number of passengers, the power of motors and of the opening of the wing elements 6 incorporated in the covering element 5 and so on, the boat 1 starts to raise from water and the hull 2 outgoes completely from water, by removing completely the effect of the wave impact and the friction of the hull 2 on water.

Therefore, when the configuration with four hydrofoils 20 is used, the planing configuration provides that the whole underwater body N is detached from the water surface .

Under such condition the boat, in order to navigate, requires a lower push, then lower power requested to the motors, then lower consumption of fuel or propulsive energy in general.

Therefore, in the navigation configuration which provides the use of the hydrofoils 20 and of the high wing 9, the control unit determines the best configuration in terms of extension of the high wing 9, weather and sea

- 19 conditions and cruise speed, with the purpose of minimizing the consumption and minimizing the mechanical efforts on the several structures, while keeping the boat in planing configuration.

Advantageously, should the strong wind prevent the wing elements 6 to extend, but should one wish to navigate with the extended hydrofoils 20, the cover 5 having a wing profile 10 too will generate its own lift which will reduce the mechanical efforts burdening on the wing profiles 22 of the hydrofoils 20.

Thanks to the adaptability of the extension of the high wing 9 in the various intermediate configuration between the contracted configuration and the expanded configuration it is substantially always possible to keep the boat in planing configuration, with the propellers more or less below the water surface (figures 17, 19, 21)

According to the embodiment of the invention which comprises an electric propulsive system with electric propulsors 18, the boat 1 comprises one or more battery packs for accumulating electric energy.

An advantage of the implementation with electric propulsive system 12 which comprises both the wing 9 in air and the hydrofoils 20, is that the maximum energy effectiveness is reached, by making the boat 1 means which can self-sustain energetically; in fact the photovoltaic panels 17 generate electric energy with which they feed the electric propulsors 18 and with which they charge the battery packs; moreover, in the moments of not navigation the photovoltaic panels 17 continue to accumulate energy, useful for a possible night navigation .

Depending upon the photovoltaic surface and factors like the weight of the boat 1, the crew, the navigation while planing and the weather and sea conditions, the boat can be wholly independent from recharges of propulsive energy 20 to the ground.

A suitable control unit guarantees the operation of the whole boat and the onboard safety. The wing 9 in air and the hydrofoils 20, when they are not active, leave unchanged the performances of the boat before implementation .

The boat 1 which has been described could be implemented ex-novo, or as retrofit applied to existing boats. Both the wing 9 in air and the hydrofoils 20 have the advantage of being able to be integrated to the current on-board plants with a simple implementation of the control stations 13, so as to result to have a minimum impact and to confer to the boat 1 itself a greater effectiveness from the energy point of view since, apart from guaranteeing equal performance, it produces a lowering of the propulsion power at least of 30%.

To the above-described motor boat with retractile carrying wings both in air and in water a person skilled in the art, with the purpose of satisfying additional and contingent needs, could bring several additional modifications and variants, all however comprised within the protective scope of the present invention, as defined by the enclosed claims.

- 21