Vertical take-off and landing aircraft

Abstract

A tail-seated vertical take-off and landing aircraft includes a cockpit integrated into a fuselage having a delta wing in a rear section relative to the cockpit and a propulsion system disposed in a front section relative to the cockpit. The propulsion system includes at least two coaxial counter-rotating propellers driven in rotation by at least two electric engines powered by a rechargeable battery.

Description

Technical Field

[0001] The present invention relates to a vertical take-off and landing aircraft, also abbreviated as VTOL (Vertical Take Off and Landing). In particular, the present invention relates to a tail-sit VTOL aircraft. Background Art

[0002] In the referenced technical field, various solutions are known for enabling vertical take-off and landing of aircraft.

[0003] Recently, in addition to aircraft with turboprop propulsion, solutions using hybrid motorization or electric motorization have also been developed.

[0004] Aircraft of this type are already known in the art. In the early 1950s, prototypes of VTOL aircraft with turboprop propulsion using two counter-rotating propellers were developed in the United States, such as the Lockheed XFV "Salmon" and Convair's XFY "Pogo". The latter had a delta wing and two vertical planes, one on the back and the other on the belly, and managed to carry out vertical take-off and landing tests, as well as high-speed horizontal flight tests, and tests of transition from vertical flight to horizontal flight (and vice versa).

[0005] However, several problems often arise, especially in terms of control during the landing phase, since when landing with the tail, the pilot can hardly see the ground and therefore cannot well perceive his distance from the ground. In addition, it is particularly difficult to adjust the power of the turboprop engine and / or the pitch of the counter-rotating propeller during landing. This can lead to serious accidents with serious consequences for the pilot.

[0006] For these reasons, the above-mentioned VTOL aircraft projects were abandoned.

[0007] Other examples of such aircraft are described in GB 2582133 A, US 10,597,153 B1 or WO 2017 / 052396.

[0008] These documents describe VTOL aircraft in which propulsion is achieved by pairs of counter-rotating propellers.

[0009] However, the Applicant has noted that in known aircraft of this type, the total unladen mass of the aircraft represents an important limiting factor.

[0010] The use of counter-rotating propellers actually represents an efficient and compact solution, which, however, is partially offset in the known solutions using hybrid or electric propulsion systems.

[0011] The presence of electric motorization, battery packs and drive systems may in fact significantly affect the weight of the aircraft, thus limiting its performance, especially in terms of autonomy.

[0012] The Applicant has also observed that another important limiting factor of the known solutions is represented by the definition of an optimal structure for the aircraft, which allows achieving a suitable balance between: the mass of the aircraft; the maneuverability of the aircraft during take-off and landing, in various phases of flight; simplicity of assembly; and, last but not least, costs.

[0013] In fact, it should be noted that these aircraft were built essentially as prototypes and were not suitable for mass production. Summary of the invention

[0014] Therefore, the technical problem of the present invention is to provide a tail-sit vertical take-off and landing aircraft which is structurally and functionally designed to at least partially remedy one or more of the disadvantages exposed with respect to the cited known technologies.

[0015] Within the scope of this problem, an object of the present invention is to provide an electrically propelled tail-seat vertical take-off and landing aircraft having improved autonomy with respect to known solutions.

[0016] Another object of the present invention is to provide an electrically propelled, tail-sit, vertical take-off and landing aircraft of relatively limited mass.

[0017] The object of the present invention is to provide an electrically propelled, tail-sit, vertical take-off and landing aircraft having a structure capable of allowing at least limited mass production.

[0018] Another object of the present invention is to provide a tail-sit vertical take-off and landing aircraft that is easy to control in all phases of the vertical phase, the horizontal phase, and in the phases of transition from vertical flight to horizontal flight and in the phases of transition from horizontal flight to vertical flight.

[0019] Another object of the present invention is to provide a tail-seat vertical take-off and landing aircraft having a high degree of safety even in the event of a possible malfunction or failure.

[0020] Another object of the present invention is to provide a tail-sit vertical take-off and landing aircraft that is easy and inexpensive to implement.

[0021] The present invention solves this problem and at least partially achieves at least one of these objects by a tail-sit vertical take-off and landing aircraft in a first aspect, comprising a cockpit integrated in a fuselage, the fuselage preferably having a delta wing in a rear section relative to the cockpit, and the propulsion system preferably being arranged in a front section relative to the cockpit.

[0022] It will be understood that the indications "front" and "rear" relating to parts of an aircraft are to be understood relative to the aircraft in the position it occupies during horizontal flight.

[0023] In some embodiments of the invention, the propulsion system includes at least one pair of coaxial counter-rotating propellers driven for rotation by at least two corresponding pairs of different electric motors powered by rechargeable batteries.

[0024] The aircraft according to the invention is therefore particularly compact and can have a relatively low unloaded mass, is easy to control and can be realized in a simple and economical manner. In fact, the use of two different engines, each driving a corresponding propeller in rotation, makes it possible to avoid complex mechanical systems compared to a solution in which only one engine is provided to drive two propellers in counter-rotation.

[0025] Preferably, the electric motor is a brushless motor powered by direct current (DC) and is mounted in the aircraft with fixed windings and a rotating housing.

[0026] In a preferred embodiment, each engine comprises a corresponding rotating housing, each housing being directly connected to a corresponding propeller. In other words, the propeller is preferably driven directly by the corresponding engine without the need for an intervening gear reducer or other motion transmission system.

[0027] Each housing is preferably integral with a respective propeller.

[0028] Advantageously, the stationary winding defines a single stator body of the electric motor.

[0029] The above features each contribute to simplifying the mechanical connection to the two coaxial counter-rotating propellers and the electrical connection to the engine.

[0030] Preferably, the aircraft comprises pitch changing means of said propellers, said pitch changing means preferably being configured to change the pitch of each of said propellers individually.

[0031] In this way, the propulsive thrust of the propeller can be varied without changing the number of propeller revolutions and therefore without a gear reducer or other drive part between the engine and the propeller. This allows in particular a higher thrust during take-off / landing and a lower thrust during flight, thus facilitating the autonomy of the aircraft.

[0032] In some embodiments, the rechargeable battery is a solid-state battery to ensure high charge capacity with reduced weight.

[0033] Preferably, the propellers are coaxial with respect to an axis of rotation, the engines are aligned with respect to the axis of rotation, the second engine of the pair of engines directly facing the first engine of the pair of engines.

[0034] This makes it possible to simplify the electrical connections of the propulsion system, to facilitate the assemblability of the aircraft. Furthermore, it also makes it possible to realize a propulsion unit that is easily assembled with the rest of the aircraft.

[0035] In some embodiments, the aircraft comprises a battery housing body in which the battery is accommodated, the housing body and the battery forming a battery unit, always in favor of simplicity of assembly of the aircraft and the possibility of realizing battery units connected in series.

[0036] Preferably, the aircraft comprises a shaft extending parallel to the axis of rotation, on which shaft said stator unit of said engine is supported.

[0037] In some embodiments, the shaft extends from a battery housing body, and the shaft is supported on the battery housing body at a first end. Preferably, the battery housing body is in turn supported on the cockpit.

[0038] According to one aspect of the invention, each propeller of the pair of propellers is supported on the shaft.

[0039] In some embodiments, the shaft is hollow so as to allow the passage of electrical connections, not shown in the figures, which allow both powering the engine and managing its control.

[0040] In some embodiments, the aircraft includes a cooling system configured to liquid cool the electric engine and the associated inverter and / or rechargeable battery, so that the optimal operating temperature of the battery and / or the engine can be maintained more efficiently and safely. The cooling can be performed by a water or oil cooling system, in particular by oil for cooling the electric propulsion system, and then, for example, by a dielectric liquid that can be in contact with the electrical components of the electric propulsion system.

[0041] Advantageously, the cavity formed in the shaft also allows for housing the ducts of the cooling system, allowing fluid to flow to the windings of the electric motor.

[0042] In some embodiments, the aircraft comprises a nose arranged in front of two coaxial counter-rotating propellers. Preferably, at least one ballistic safety parachute is housed in the nose. This allows to ensure a high degree of safety in the event of a failure of the propulsion system. In fact, in the event of a failure of the propulsion system, the ballistic parachute can be ejected to allow the aircraft to decelerate in the event of a descent with the tail oriented towards the ground.

[0043] Preferably, the battery housing body, the cooling system and the propulsion system are aligned along the axis of rotation and are arranged in this order with respect to one another in a direction proceeding from the rear to the front of the aircraft.

[0044] In some embodiments, a first propeller of a pair of propellers is interposed between the cooling system and the first engine.

[0045] Preferably, the shaft comprises a second end portion which projects in the axial direction relative to the respective propeller of the pair of propellers, the nose being supported on the second end portion. This feature allows simplifying the fixing of the nose.

[0046] In a preferred embodiment, the cockpit, the battery unit, and the propulsion system formed of a propeller and an engine are each made as different components and are configured to be installed sequentially in the axial direction.

[0047] Preferably, the cooling system is made as a different component with respect to the cockpit, the battery pack and the propulsion system, and the cooling system is configured to be installed between the battery pack and the propulsion system along the rotation axis.

[0048] It will be appreciated that the use of aligned components, combined with the absence of a gear reducer and associated transmission section, further allows for the realization of separate modules that can be assembled with simple mechanical and electrical connections.

[0049] In one embodiment, one or more airbags are arranged in the rear section of the fuselage and / or in the cockpit of the aircraft to cushion the impact with the ground in the event of any emergency landing.

[0050] In one embodiment, the cockpit comprises at least two side-by-side seats. The two side-by-side seats comprise at least one tilting seat, preferably two tilting seats, which seats have manually and / or automatically adjustable rotation.

[0051] In some embodiments, the reclining seat is configured such that when the aircraft is resting on the ground in a takeoff / landing configuration, the reclining seat rotates on command about an axis substantially perpendicular to the axis of rotation of the propeller and substantially parallel to the ground.

[0052] The cockpit may comprise at least one transparent tiltable shell which is hinged to the fuselage of the aircraft in a front part of the tiltable shell to allow at least one pilot to enter one of two side-by-side seats and which can be safely reclosed during flight.

[0053] The aircraft according to the invention comprises a programmable control unit for controlling and regulating one or more of the following:

[0054] - Power of two electric motors;

[0055] - Rotation of the tilting seat;

[0056] - the pitch of the propeller;

[0057] -Battery charge status;

[0058] - aircraft flight attitude;

[0059] - the transition phase between vertical and horizontal flight; and

[0060] - The route the aircraft is to follow.

[0061] At least the fuselage of the aircraft according to the invention is made of strong and light materials, such as carbon fibers, aluminum or alloys thereof, and titanium or alloys thereof.

[0062] In this specification and the appended claims, unless expressly indicated otherwise, certain terms and expressions are deemed to have the meanings expressed in the following definitions.

[0063] In the context of the present invention, the expressions "substantially parallel" and "substantially perpendicular" shall denote possible deviations of ±10°, preferably ±5°, from perfect parallelism and perpendicularity, respectively. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] Further features and advantages of the present invention will become more apparent from the following description which is given by way of illustration and not limitation and with reference to the accompanying drawings, in which:

[0065] - Figure 1 is a perspective view of an aircraft in a horizontal flight attitude according to an embodiment of the present invention;

[0066] - Figure 2 yes Figure 1 An elevation view of an aircraft with the tail of the aircraft sitting on the ground;

[0067] - Figure 3 and Figure 3A is based on Figure 2 a sectional view of the aircraft in plane III-III and the corresponding detailed views; and

[0068] - Figure 4 is a schematic diagram showing details of the cockpit with the shell open. DETAILED DESCRIPTION

[0069] First reference Figure 1 The tail-sit vertical take-off and landing aircraft according to an embodiment of the present invention is generally indicated by reference numeral 10. Figure 1 , the aircraft 10 is shown in a level flight attitude.

[0070] The aircraft 10 comprises a cockpit 20 integrated in a fuselage 30 having a delta wing 31 and provided with movable ailerons 32 in a rear section relative to the cockpit 20. In a front section relative to the cockpit 20 a propulsion system 4 is provided, comprising two coaxial counter-rotating propellers 41 and 42, which are driven in rotation by two respective electric motors 43 and 44. In a preferred embodiment, the propellers 41, 42 rotate relative to a common axis of rotation X. In a preferred embodiment, the nose 40 is arranged in front of the propellers 41 and 42.

[0071] exist Figure 1 In the view of FIG. 3 , an upper drift and a lower drift or vertical tail 33 with corresponding rudders 34 can also be seen.

[0072] Advantageously, the wings 31 and the yaw members 33 are provided with wheels 35 which allow the aircraft 10 to rest on the ground by means of the tail section, for example as follows Figures 2 to 4 In the preferred embodiment, the wheel 35 is located at the respective end of the wing and is drifted distally relative to the cockpit 20 .

[0073] Figure 2 An elevation view of the aircraft 10 in a vertical position with the tail section resting on the ground is shown. The two side-by-side seats in the cockpit 20 are highlighted by making the transparent shell 22 ( Figure 4 ) to enter the two side-by-side seats.

[0074] Also highlighted is a programmable control unit 50, the interface of which is provided in the cockpit 20, which allows the various functions of the aircraft 10 to be controlled and adjusted, such as the power of the electric engines 43 and 44, the state of charge of the batteries, the flight attitude of the aircraft 10, the transition phases between vertical and horizontal flight, the route to be followed by the aircraft 10, and generally all the signaling functions and automation that allow the aircraft 10 to fly in a safe state.

[0075] Preferably, an airbag 60 is provided in the cockpit 20 as an additional safety system for the occupants of the aircraft 10 .

[0076] exist Figure 3 The cross-sectional view and Figure 3A In the relative detail of the 3D-printed version of the invention, the arrangement of the electric motors 43 and 44 and the battery unit 7 and the arrangement of the relatively rechargeable solid-state batteries 70 responsible for their power supply are highlighted. The electric motors 43 and 44 may be, for example, brushless direct current motors equipped with fixed windings 43A, 44A and rotating housings 43B, 44B, each of which is mechanically connected to a respective propeller 41 and 42.

[0077] In a preferred embodiment, the rotating housing of each engine (forming its rotor) is directly connected to the corresponding propeller. In other words, the propeller is driven directly by the corresponding engine without the need for an intervening gear reducer or other motion transmission system.

[0078] In some embodiments, the windings 43A, 44A (which more generally define a stator unit of the electric machine) are arranged between the two propellers.

[0079] In some embodiments (not shown in the figure), two engines can use a single stator unit, which includes a support to which the windings 43A, 44A of each engine are fixed. In this way, the two windings can use a common cooling circuit, which is always beneficial for simplifying the construction and facilitating assembly.

[0080] from Figure 3A It can be clearly noted that, in the preferred embodiment, the two electric motors include: a first electric motor 43 ; and a second electric motor 44 arranged in front of the first electric motor 43 .

[0081] Preferably, the engines 43 and 44 are aligned relative to the axis of rotation X of the propellers 41 , 42 , with the second engine 44 directly facing the first engine 43 .

[0082] The aircraft 10 may also comprise a shaft 45 extending parallel to the axis of rotation X, on which the stator units of the engines 43 , 44 are supported.

[0083] In a preferred embodiment, the battery unit 7 includes a battery housing body 71 in which the battery 70 is accommodated.

[0084] The shaft member 45 preferably extends from the battery housing body 71 , and the shaft member 45 is supported on the battery housing body 71 at the first end 45A. The battery housing body 71 is in turn supported on the cockpit 20 .

[0085] According to one aspect of the present invention, the propellers 41 and 42 are also supported on the shaft 45 via corresponding bearings (not shown in the figures).

[0086] The shaft 45 may also be hollow so as to allow the passage of electrical connections (not shown in the figures), which allow both the supply of electricity to the engine and the management of its control.

[0087] In some embodiments, a cooling system 74 (preferably using liquid) is arranged between the engines 43, 44 and the battery housing body 71 to cool the engines and / or batteries in conjunction with the airflow generated by the propellers 41 and 42 during flight.

[0088] In fact, it should be noted that the battery housing body 71 , the cooling system 74 and the engines 43 , 44 are aligned along the axis of rotation X and are arranged in this order relative to one another in a direction proceeding from the rear to the front of the aircraft 10 .

[0089] Advantageously, the first propeller 41 is also interposed between the cooling system 74 and the first engine 43 .

[0090] In the nose 40 there is obtained a housing 48 containing at least one ballistic safety parachute which can be operated in the event of a malfunction of the aircraft 10 to ensure a descent with deceleration and subsequent contact of the tail with the ground.

[0091] The shaft 45 may advantageously include a second end 45 b protruding in the axial direction relative to the second propeller 44 , so as to allow the nose 40 to be fixed.

[0092] It will be appreciated that the cockpit 20, the battery unit 7, the cooling system 74, and the propulsion system formed by the propellers 41, 42 and the engines 43, 44 may be made as distinct components.

[0093] When assembling the aircraft, these parts can be assembled according to the axial sequence described above, possibly combined by the shaft 45.

[0094] exist Figure 3In the view of FIG. 1 , the pilot P is shown sitting on a seat 80 in the position assumed during flight. Each seat 80 in the cockpit 20 is a reclining seat that can be operated and adjusted to rotate according to command. In fact, as Figure 4 As shown, in order to allow the pilot P and any passengers to enter or leave the cockpit 20, the seat 80 is in a suitable position to allow the pilot P and any passengers to be seated, and the pilot P and any passengers enter the cockpit 20 after tilting the corresponding transparent shell 22. Then before the flight begins, the transparent shell 22 is safely closed again.

[0095] To this end, it is conceivable that when the aircraft is resting on the ground by means of the wheel-like member 35, the seat can be moved around. Figure 2 An axis Y of rotation is shown which is substantially perpendicular to the axis of rotation X and substantially parallel to the ground.

[0096] Then the take-off phase can be carried out, in which the aircraft 10 rests on the ground S by means of the wheels 35, the seats 80 are in a rotated position, i.e. the passengers are positioned to sit, with the torsos substantially standing, i.e. substantially aligned with the vertical, as shown in FIG. Figure 4 Shown schematically.

[0097] After takeoff, the seat 80 can be rotated about the aforementioned axis Y to realign the seated passengers with the vertical orientation.

[0098] It will be appreciated that this feature makes the aircraft of the invention more usable, facilitates access and makes the cruising phase more comfortable.

[0099] The aircraft 10 may also include a propeller pitch changing device 47 (in Figure 3A The pitch variation device 47 is preferably configured to function during the transition between the take-off / landing and horizontal flight phases.

[0100] The pitch changing device can be used to change the pitch of each propeller individually by adjusting the propulsive thrust of the propeller without changing the number of revolutions of the propeller.

[0101] This allows for higher thrust during takeoff / landing and lower thrust during flight, thus allowing for increased autonomy of the aircraft.

[0102] Various modifications may be made to the embodiments described and depicted above. For example, the arrangement of the engine and the battery in the aircraft may also be different from that described so far in the various embodiments, and the arrangement of the airbags in the cockpit and / or the arrangement of the cooling system for the engine and the battery may also be different from that described so far in the various embodiments.

Claims

1. A tail-sit vertical take-off and landing aircraft (10), comprising a cockpit (20) integrated in a fuselage (30), the fuselage having a delta wing (31) in a rear section relative to the cockpit, and a propulsion system (4), characterized in that: The propulsion system (4) comprises at least a pair of coaxial counter-rotating propellers (41, 42), which are driven to rotate by corresponding pairs of different electric motors (43, 44), which are powered by a battery unit (7) including a rechargeable battery (70), wherein each of the electric motors (43, 44) is configured to drive a corresponding propeller in the pair of counter-rotating propellers (41, 42) to rotate.

2. The aircraft (10) according to claim 1, wherein: The electric motors (43, 44) are brushless motors powered by direct current.

3. An aircraft according to claim 1 or 2, wherein: The electric motor (43, 44) has a stationary winding (43A, 44A) and a rotating housing (43B, 44B).

4. Aircraft (10) according to the preceding claim, wherein: Each engine includes a respective rotating casing, each casing being directly connected to a respective propeller.

5. An aircraft (10) according to any one of the preceding claims, wherein: The propellers (41, 42) are driven directly by the corresponding engines (43, 44) without the intervention of a gear reducer.

6. The aircraft (10) according to any one of the preceding claims, comprising pitch changing means (47) of the propellers (41, 42), the pitch changing means being configured to change the pitch of each of the propellers (41, 42) individually.

7. An aircraft (10) according to any one of the preceding claims, wherein: The propellers (41, 42) are coaxial with respect to an axis of rotation (X), the engines (43, 44) are aligned with respect to the axis of rotation (X), the second engine (44) of the pair of engines directly facing the first engine (43) of the pair of engines.

8. An aircraft (10) according to any one of the preceding claims, comprising a battery housing body (71) in which the battery (70) is accommodated.

9. An aircraft (10) according to any one of the preceding claims, comprising a shaft (45) extending substantially parallel to the axis of rotation (X) and on which the windings (43A, 44A) of the engines (43, 44) are supported.

10. An aircraft (10) according to claims 8 and 9, wherein: The shaft member (45) extends from the battery housing body (71), and the shaft member (45) is supported on the housing body (71) at a first end portion (45A) of the shaft member.

11. An aircraft (10) according to any one of the preceding claims, wherein: The battery housing body (71) is supported on the cockpit (20).

12. An aircraft (10) according to any one of the preceding claims when dependent on claim 9, wherein: Each propeller in the pair of propellers is supported on the shaft (45).

13. An aircraft according to any preceding claim when dependent on claim 9, wherein: The shaft member (45) is hollow.

14. An aircraft according to any one of the preceding claims, wherein: The rechargeable battery (70) is a solid-state battery.

15. An aircraft according to any one of the preceding claims, comprising a cooling system (74) configured to liquid-cool the electric motor (43, 44) and / or the rechargeable battery (70).

16. An aircraft (10) according to the preceding claim when referring to claims 7 and 8, wherein: The battery housing body (71), the cooling system (74) and the propulsion system (4) are aligned along the rotation axis (X) and are arranged in this order relative to each other along a direction of travel from the rear to the front of the aircraft (10).

17. An aircraft (10) according to any one of the preceding claims when dependent on claim 15, wherein: A first propeller (41) of the pair of propellers is interposed between the cooling system (74) and the first engine (43).

18. An aircraft (10) according to any one of the preceding claims when dependent on claim 15, wherein: The cooling system (74) is supported on the shaft (45).

19. An aircraft (10) according to the preceding claim when dependent on claim 13, wherein: The cooling system (74) comprises a pipe extending inside the shaft (45) for passing a cooling liquid.

20. An aircraft according to any one of the preceding claims, further comprising a nose (40) arranged in front of two coaxial counter-rotating propellers (41, 42), wherein: Preferably, at least one ballistic safety parachute is housed in the nose.

21. An aircraft (10) according to the preceding claim when dependent on claim 9, wherein: The shaft member (45) includes a second end portion (45b) protruding in an axial direction relative to a corresponding propeller (42) of the pair of propellers, and the nose (40) is supported on the second end portion (45b).

22. An aircraft (10) according to any one of the preceding claims, wherein: The cockpit (20), the battery unit (7), and the propulsion system (4) formed of a propeller and an engine are each made into different components and are configured to be installed sequentially in an axial direction.

23. An aircraft (10) according to any one of the preceding claims when dependent on claim 15, wherein: The cooling system (74) is made as a different component relative to the cockpit (20), the battery unit (7) and the propulsion system (4), and the cooling system (74) is configured to be installed between the battery unit (7) and the propulsion system (4).

24. An aircraft (10) according to any one of the preceding claims, wherein: One or more airbags (60) are arranged in the rear section of the fuselage and / or in the rear section of the cockpit of the aircraft to cushion the impact with the ground in the event of any emergency landing.

25. An aircraft (10) according to any one of the preceding claims, wherein: The cockpit (20) comprises at least two seats arranged side by side.

26. An aircraft (10) according to any one of the preceding claims, wherein: The cockpit (20) comprises at least one reclining seat (80) configured so that, when the aircraft is resting on the ground in a take-off / landing configuration, the reclining seat rotates on command about an axis (Y) substantially perpendicular to the axis of rotation (X) of the propeller and substantially parallel to the ground (S).

27. An aircraft (10) according to claims 25 and 26, wherein: The at least two side-by-side seats include at least two tilting seats (80) capable of adjustable rotation.

28. An aircraft (10) according to any one of the preceding claims, wherein: The cockpit (20) comprises at least one transparent tiltable shell which is hinged to the fuselage of the aircraft (10) in a front part of the tiltable shell to allow at least one pilot to enter and which can be safely reclosed during flight.

29. An aircraft (10) according to any one of the preceding claims, wherein: The aircraft comprises a programmable control unit (50) for controlling and adjusting one or more of the following: - the power of at least two of said electric motors; - Rotation of the tilting seat; - the pitch of the propeller; - the charge state of the battery; - the flight attitude of the aircraft; - the transition phase between vertical and horizontal flight; and - the route to be followed by the aircraft.

30. An aircraft (10) according to any one of the preceding claims, wherein: At least the fuselage of the aircraft is made of strong and lightweight materials, including carbon fiber, aluminum or its alloy, and titanium or its alloy.

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