The present invention relates to a combined surface and submarine vessel for transport of goods such as, for example, LNG and/or other liquid goods, and any personnel, comprising a hull, which in surface state is adapted to float on a water surface, and where the vessel is equipped with at least a pilothouse/ wheelhouse that can be raised or lowered so that it extends above the deck of the vessel, and a propulsion system.

In connection with transport of goods and cargo, and passengers for that matter, between the East and the West it has for many years been desirable to use, for example, the Northeast Passage or the Northwest Passage over the Northern Hemisphere. The passages are initially only open for sea traffic in the summer as they are blocked by ice in the winter. Although it has been shown lately that, due to global warming, vessels can travel outwith the summer season through the Northeast Passage, it has been required to have icebreakers as part of the convoy. To break up the ice regularly in connection with transport in areas that are covered by ice through the year has a considerable negative environmental effect. This leads to a considerable increase in the latent melting and drifting of ice and contributes to an acceleration of the melting of ice which again is a negative factor for the global environment.

Therefore, it will be very environmentally friendly and expedient to have a vessel in the form of, for example, a cargo ship that can travel both on and under the water surface, as proposed according to the present invention. This without having to break the ice or use the help of ice-breakers.

In addition to manoeuvring in Arctic areas, the invention will also be able to contribute to increased safety, and then, in particular, in extreme weather conditions, in that the vessel can operate in a submersed state if the conditions for surface operation should become too difficult. This could be carried out wherever the vessel is travelling. During operation on the water surface a vessel according to the invention will be fitted and function as a normal ship, and for propulsion under water it can be fitted and, in the main, function as a submarine. A standard definition of a submarine, normally called a U-boat, is a manned vessel that can operate independently under the surface of the ocean. A U-boat functions in principle by reducing its buoyancy in a controlled way so that it can dive below the water surface and operate in a submersed state. This is done in that the U-boat is constructed with a pressure-resistant hull onto which are fitted ballast tanks with controllable valves at the top and open valves at the bottom. The ballast tanks are used to give the U-boat a positive buoyancy by emptying the tanks of water with the use of high-pressure air and correspondingly give the U-boat a negative buoyancy by letting the air out of the tanks. These tanks are often called the main ballast tanks, as it is they which give the boat a positive buoyancy when it has surfaced (on the surface). If the U-boat is too heavy it will sink to the bottom, and if it is too light it will float up even if the ballast tank are filled with water. To avoid these problems the U-boat is fitted with smaller regulating tanks that are used to finely adjust the weight of the U- boat so that it weighs as much as the water it displaces. If the U-boat changes its speed, the water in the regulating tanks must be, as a rule, adjusted so that the hydrodynamics and weight of the U-boat together contribute to it neither floating up nor sinking. The amount of water that is regulated varies with the size of the U-boat and the hydrodynamics of the hull. The present vessel can be equipped as explained above, but with special adaptions. Among other things, the hull does not need to be as pressure resistant as the purpose of the vessel according to the invention is to be sufficiently submersed to be able to sail under the ice. Furthermore, the ballast tanks could be adapted to be cargo tanks.

From prior art, reference is made to US 4,799,825 A, which shows a U-boat that can be used as an underwater tanker for freight of crude oil and gas under water in connection with oil operations in arctic areas. The U-boat is fitted for anchoring to, and tanking from, underwater installations and in this context can comprise valves for the loading and unloading and an extendable probe like connection to the underwater installation in connection with the tanking and unloading. The difference between the U-boat in US 4,799,825 A and a normal U-boat is consequently that the U-boat comprises cargo tanks for oil and gas, and is equipped for loading and unloading under water whilst it is anchored to an underwater installation. The document does not mention anything about normal surface operation for transport of oil or the gas, or that the U-boat is equipped with a wheelhouse. A U-boat can naturally be able to operate in a normal surface state, but the whole purpose of using the U-boat as described will then disappear.

Maheshwar "Presentation on Improving Safety and Propulsion Efficiency of Ships using Retractable Bridge", Ship Production Symposium, 2012

Providence, Rhode island, USA, 24-25 October 2012, shows a conventional surface vessel with a retractable wheelhouse. The document does not mention anything about operation under water. The aim of the solution described in the document is to optimise the areas of the vessel which are exposed directly to wind loads to reduce the aerodynamic wind resistance of the vessel and which for this reason gives a total reduction of the fuel consumption.

According to the invention, a submersible vessel is provided for the transport of goods and any personnel, comprising a hull which, in a surface state, is adapted to float on a water surface, and where the vessel is at least equipped with a wheelhouse that extends above the deck of the vessel, and a propulsion system, where the vessel for submarine propulsion under water is equipped so that it can be lowered below the water surface and to change from surface operation to underwater operation, and also that the whole, or at least one part of the wheelhouse, is arranged to be retracted into the deck/hull of the ship. In more detail, a vessel is provided for the transport of goods, and any personnel, comprising a hull which in a surface state is adapted to float on a water surface and where the vessel comprises a bow section, an aft section equipped with propulsion means in the form of a propeller mounted onto a driveshaft and a rudder blade arranged vertically adjoining the propeller, and also a deck that extends at least partially between the bow section and the aft end, where said deck is equipped with a wheelhouse that extends above the deck of the vessel, and where the vessel comprises a number of cargo tanks or cargo rooms. The vessel is characterised in that it is adapted for submersion below the water surface and for submarine propulsion under water, as the vessel comprises ballasting means for adjusting the buoyancy, a number of rudder devices that extend horizontally out from the hull for the steering of the angle of the vessel in the water, and also that the wheelhouse is arranged to be retracted into the vessel deck, where the wheelhouse, when in retracted state is arranged completely, or partially, in a room in the vessel deck.

Alternative embodiments are given in the respective dependent claims.

The vessel can comprise a number of cargo tanks or cargo rooms, where the cargo tanks can be LNG tanks, such as so-called "Moss type, Membrane tanks", a new design or tanks for transport of oil or other goods.

Cables and the like to the pilot house/crew house and steering systems of the vessel can be arranged in flexible cable chains, where the cable chains extend into or adjoining the room under the vessel deck, and/or signals can be transmitted by wireless transmissions.

Furthermore, the vessel preferably comprises ballast tanks for the regulation of vessel buoyancy.

The wheelhouse, or a section of the wheelhouse, can be arranged to be released and made clear to function as an independent evacuation unit. The vessel can also be equipped with one or more life-saving rafts that are retracted into the deck and that are arranged to be released manually and/or

automatically after given parameters.

Furthermore, a coat or a cover can be arranged over the ordinary deck, where said coat or cover can be aligned with the retractable wheelhouse when the wheelhouse is retracted. The rudder devices, that extend horizontally out from the hull for the steering of the angle of the vessel in the water, can be formed with a streamlined profile, and the rudder devices can be extracted from, and retracted into, the hull.

The invention shall now be described in more detail with reference to the enclosed figures, in which:

Figures 1 and 2 show a schematic embodiment of a vessel according to the invention.

As can be seen in the figures a vessel 10 is shown for, for example, transport of goods, in the example shown liquid natural gas (LNG) is stored in tanks 22. Naturally, the vessel will also be able to transport other types of goods and materials and any passengers. In particular, transport of vehicles will also be expedient between the East and the West. Furthermore, the vessel comprises, in a known way, a hull 12 and a propulsion system. Known rudder

arrangements are used in connection to the propulsion system. A wheelhouse 14 is mounted in and on the vessel deck 16.

The hull 12 is formed with a bow section 30, possibly in a bulb shape, and an aft end 40 is equipped with a rudder, such as a vertically arranged and twistable rudder 32. The rudder 32 can, for example, be of a known suspension type and be connected to a steering worm at the aft end 40 of the vessel 10. The propulsion system can comprise a propeller 18 mounted to a driveshaft 34 and where the driveshaft is further connected to a motor (not shown).

Contrary to normal surface vessels, the wheelhouse 14 according to the invention can be retracted into the deck 16. The wheelhouse 14 can preferably be completely retractable, but also partially retractable, thus to reduce the depth when the vessel moves under the surface of the water. The wheelhouse 14 can be retracted into a room 20 under the deck 16, and in this connection cables and the like to the steering system of the vessel 10 can be arranged in flexible cable chains where the cable chains run into or adjoining the room 20 under the vessel deck 16. The signals to the steering systems can also be transmitted wirelessly.

Other equipment on the deck 16 will also be able to be retractable or collapsible and all hatches or entries and openings can be sealed against ingress of water. Furthermore, a coat 28 or cover can be arranged over the ordinary deck 16. As can be seen in figure 2, said coat 28 or cover can be aligned with the

retractable wheelhouse 14 when the wheelhouse is retracted. In addition, the wheelhouse 14 can have a function as an evacuation section and, in a simple procedure, can be released and made free from the hull 12 such that it, in this case, will make up an independent floating unit. Alternatively, a section 26 of the wheelhouse can be released from the rest of the

wheelhouse as an independent floating unit, for example, the uppermost section as shown in figure 1 . The wheelhouse 14 or the section 26, in this case, can be self-contained and equipped with its own propulsion means and also be able to be released both in a submersed and surface state.

In addition, the vessel could be equipped with one or more life-rescue rafts 24 that are, for example, retracted into the deck 16 and which can be released manually and/or automatically after given parameters.

Thus, when sailing on the surface of the water, the vessel 10 will be driven as a completely normal vessel. For submersion into the water, the vessel 10 will be equipped with ballast tanks 42 or other ballasting means and, like a U-boat, be equipped for operation under water. The ballast tanks 42 are shown

illustratively in the figures and can be placed where it is suitable to have them. Similarly, the ballast tanks and any regulating tanks will be able to be controlled in cooperation with the degree of filling in the cargo tanks. Alternatively, one or more of the cargo tanks 22 can also be used as ballast tanks.

The hull 12 does not need to be pressure resistant as the vessel according to the invention shall initially only be sufficiently submersed in water to be able to sail under the ice, i.e. in the main, be submersed just under the water surface or the layer of ice, or sufficiently under the water surface in extreme weather conditions not to be influenced to any large extent by the weather.

The rudder devices to steer the angle of the vessel under water, whether in the lengthwise or sidewise direction, can be formed in a known way and can also be retractable into the hull 12 of the vessel during normal operations. The rudder devices 38 are preferably arranged horizontally with respect to the hull and can have a streamline form and be mounted on a shaft in the hull 12 so that they can be turned.

A vessel with equipment for normal operation is considered to be known to one skilled in the arts and is therefore not explained in any detail. The

corresponding is the case for a U-boat.