Three-surface hybrid vertical take-off and landing aircraft

Abstract

Disclosed in the present invention is a three-surface hybrid vertical take-off and landing aircraft, comprising a canard fuselage, front wing assemblies, middle wing assemblies and rear wing assemblies. The front wing assemblies, the middle wing assemblies and the rear wing assemblies are sequentially arranged on the canard fuselage in the front-back direction of the canard fuselage; and two front wing assemblies, two middle wing assemblies and two rear wing assemblies are symmetrically arranged on two sides of the canard fuselage, wherein each front wing assembly comprises a front wing body, a first power unit and a first float mechanism; the front wing body is fixedly connected to the canard fuselage, and the first float mechanism is installed below the front wing body; the first power unit is installed on the front wing body; and the first power unit is installed on the front wing body, and in a shutdown state, the first power unit is in a tilted state so as to provide torque capable of lifting the canard fuselage. The present invention can be lifted more easily during a take-off stage.

Description

A three-wing hybrid vertical take-off and landing aircraft

[0001] This application claims priority to Chinese patent application No. 202311299685X filed with the China Patent Office on October 7, 2023, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present invention relates to the field of aerospace technology, and in particular to a three-wing hybrid vertical take-off and landing aircraft. Background Art

[0003] Fixed-wing VTOL aircraft need to achieve an organic combination of vertical takeoff and landing and efficient horizontal flight. Currently, there are several configuration options: composite wing configuration: fixed wing as the main body, with a multi-rotor module added, using the multi-rotor module for takeoff and landing; tilt-rotor configuration: part or all of the rotors of the fixed wing can be tilted. During takeoff and landing, the rotors provide lift in the horizontal plane. During level flight, part or all of the rotors are tilted to the longitudinal axis plane of the fuselage to provide flight pull or thrust; tail-seat layout: the nose is upward during takeoff and landing, and the entire aircraft tilts to achieve flight phase switching. Self-tilting cantilever VTOL aircraft use the differential of distributed power and a specially designed belly curve or skid to achieve full aircraft tilting. Compared with the composite layout, the additional drag brought by the vertical takeoff power unit is smaller. Compared with the tilt-rotor and tilt-wing layouts, there is no mechanical tilting mechanism, and the aircraft structure is simple and light.

[0004] A three-wing layout is common in composite vertical takeoff and landing (VTOL) aircraft. Its main wing, canards, and horizontal tail are essentially located in the same horizontal plane, as shown in patents CN211685619U and CN107571994B. The front and rear wings primarily serve to connect and balance the pitching moment of the main wing and do not generate positive lift. Therefore, the main wing, like conventional fixed-wing aircraft, adopts a large wingspan design, which imposes certain requirements on the landing and takeoff area width. For water takeoff and landing, as shown in patent CN211685619U, a large wingspan design is not conducive to handling choppy water conditions. Patent CN115230963A describes a three-wing layout aircraft based on a tilting duct design. All three wings generate positive lift, sharing the aerodynamic loads of the main wing. This improves aircraft stability and reduces structural weight. Its wing height distribution is: the mid-wing is highest, the front wing is next, and the rear wing is lowest. Therefore, in level flight, the rear wing is immersed in the downwash of the mid-wing, reducing its aerodynamic performance.

[0005] Furthermore, for vertical takeoff and landing (VTOL) fixed-wing aircraft, high-power power units are required to generate lift during takeoff and landing. Highly dynamic distributed power units are also used during this phase to generate attitude control forces. This results in lower power consumption during fixed-wing level flight. The concept of hybrid power for VTOL aircraft is generally illustrated in patents CN212797308U and CN112046764B.

[0006] A tilting swivel-body vertical take-off and landing aircraft is provided with a curved belly curve or skid to meet its special "tumbling" take-off and landing method. For example, a certain type of aircraft of a certain company uses a curved belly curve to complete a smooth transition of take-off and landing. For example, patent CN115503952A uses an "eight-shaped" skid to achieve this process.

[0007] The curved belly design of a company's tilting VTOL aircraft not only meets the aircraft's attitude changes during tilting takeoffs and landings, but also serves as buoyancy during water takeoffs and landings, keeping components such as the powertrain above water. However, the aircraft has not been verified for water takeoffs and landings. While the curved fuselage can serve as buoyancy to achieve a large displacement, the narrow tail section has limited drainage capacity. Preliminary simulations based on the present invention show that the tail section, including the rear wing, would be completely submerged in water during a vertical landing.

[0008] Existing tilting cantilever VTOL aircraft, including a certain company's aircraft and patent CN115503952A, all utilize a dual-wing layout. To facilitate a roll, the tilting cantilever requires a relatively rearward center of gravity. This, in turn, requires a larger span of the rear wing to maintain static stability. This negatively impacts takeoff and landing operations, requiring a wider landing field and increasing the risk of the rear wing contacting the ground during takeoff and landing. Consequently, the center of gravity of the dual-wing layout must be shifted forward as much as possible, relative to the center of the two wings. This shortens the lever arm for the front wing's pull, making rolls more difficult.

[0009] A feasible solution, as described in patent CN115503952A, involves using the front wing to generate thrust, while the rear wing's propellers reverse at the moment of "tumbling" to create a counter-force. This creates a force couple between the front and rear wing's thrust. Once the aircraft is upright, the rear wing's propellers reverse and, together with the front wing, generate thrust to lift the aircraft off the ground. This creates severe alternating loads on the rear wing's powertrain, severely reducing the lifespan of the motor and other components.

[0010] In summary, existing aircraft designs are unable to meet the requirements for specialized water-based takeoff and landing applications. Improving the flight time of vertical takeoff and landing (VTOL) aircraft and making them easier to launch are key challenges in this field.

[0011] Summary of the Invention

[0012] The purpose of the present invention is to provide a three-wing, hybrid vertical take-off and landing aircraft to address the deficiencies in the prior art. The aircraft can be more easily lifted off during take-off, increase flight time, and better adapt to water take-off and landing.

[0013] The present invention provides a three-wing hybrid vertical take-off and landing aircraft, comprising a stilt-body fuselage, a front wing assembly, a middle wing assembly, and a rear wing assembly; the front wing assembly, the middle wing assembly, and the rear wing assembly are sequentially arranged on the stilt-body fuselage along the front-to-back direction of the stilt-body fuselage; the front wing assembly, the middle wing assembly, and the rear wing assembly are each two, and are symmetrically arranged on both sides of the stilt-body fuselage;

[0014] Wherein: the canard assembly includes a canard body, a first power group and a first float mechanism; the canard body is fixedly connected to the stilt fuselage, the first float mechanism is installed below the canard body; the first power group is installed on the canard body;

[0015] The first power group is installed on the front wing body. In the stopped state, the first power group is in a tilted state to provide a moment that can tilt the tilted fuselage.

[0016] The three-wing, hybrid vertical take-off and landing aircraft as described above, wherein optionally: in a level flight state, the front wing assembly, the middle wing assembly and the rear wing assembly are arranged in sequence from low to high along the height direction of the fuselage.

[0017] The three-wing, hybrid vertical take-off and landing aircraft as described above may optionally further include a connecting wing connecting the middle wing assembly and the rear wing assembly on the same side of the cantilever fuselage; the connecting wing is inclined outward from the front to the rear.

[0018] The three-wing hybrid vertical take-off and landing aircraft as described above, wherein, optionally, the first buoy mechanism includes a load-bearing bracket, a buoy body, a telescopic member and a buoy wheel;

[0019] The upper end of the load-bearing bracket is connected to the front wing body, and the lower end is connected to the pontoon body; the lower end of the telescopic member is hinged to the pontoon wheel, and the upper end is hinged to the front wing body.

[0020] The three-wing hybrid vertical take-off and landing aircraft as described above, wherein, optionally, the mid-wing assembly includes a mid-wing body and a second power group;

[0021] The second power group is installed on the middle wing body;

[0022] The center of gravity of the aircraft is located on the plane where the middle wing body is located.

[0023] The three-wing hybrid vertical take-off and landing aircraft as described above, wherein, optionally, the mid-wing assembly further includes a second float mechanism;

[0024] The second buoy mechanism is installed at the bottom of the middle wing body.

[0025] The three-wing hybrid vertical take-off and landing aircraft as described above, wherein, optionally, the rear wing assembly includes a rear wing body and a third power group;

[0026] The third power group is installed on the rear wing body.

[0027] The three-wing, hybrid vertical take-off and landing aircraft as described above, wherein optionally: in the length direction of the cantilever fuselage, the distance between the front wing body and the middle wing body is greater than the distance between the middle wing body and the rear wing body.

[0028] The three-wing hybrid vertical take-off and landing aircraft as described above, wherein optionally, at least one of the front wing body, the middle wing body and the rear wing body is configured with a control surface.

[0029] The three-wing hybrid vertical take-off and landing aircraft as described above, wherein, optionally, the lengths of the front wing body, the middle wing body and the rear wing body increase sequentially.

[0030] The three-wing, hybrid vertical take-off and landing aircraft as described above, wherein optionally: the dihedral angle of the front wing body is 6-8 degrees, the dihedral angle of the middle wing body is 7-9 degrees, and the dihedral angle of the rear wing body is 6-8 degrees.

[0031] The three-wing hybrid vertical take-off and landing aircraft as described above, wherein optionally: the sweep angle of the front wing body is 7-13 degrees, the sweep angle of the mid-wing body is 15 to 25 degrees, and the sweep angle of the rear wing body is -5 to 5 degrees.

[0032] The three-wing, hybrid vertical take-off and landing aircraft as described above is characterized in that: the first power group, the second power group and the third power group are each composed of a power unit and a propeller;

[0033] The power devices of the first power group and the second power group are electric power units, and the power device of the third power group is a hydrogen power unit or a fuel power unit; or, the power devices of the first power group and the second power group are hydrogen power units or fuel power units, and the power device of the third power group is an electric power unit.

[0034] Compared to existing technologies, the triplane cantilever proposed in this invention is more prone to "rolling" than a biplane. At the same takeoff weight, the triplane design has a smaller wingspan than the biplane cantilever configuration, resulting in a correspondingly smaller space requirement, making it more convenient for direct transport of ships, containers, trucks, and the like, while also requiring less width for takeoff and landing areas. The triplane's power layout offers greater flexibility in hybrid designs. Existing biplane cantilever aircraft utilize four power units on the front and rear wings, respectively. To ensure that the line of force passes through the center of gravity and maintain bilateral symmetry during level flight, two similar hybrid power layouts exist: the four inner power units utilize fuel (or hydrogen) power units, while the four outer power units utilize electric power units, or vice versa. A triplane, on the other hand, can utilize fuel (or hydrogen) power units for the two power units on the center wing, or fuel (or hydrogen) power units for the four power units on the front and rear wings, adapting to varying power requirements for level flight and offering greater flexibility compared to a biplane. Furthermore, if a biplane were to incorporate winglets, these would be relatively long, requiring significant weight gain to achieve the desired increase in airframe structural rigidity. The three-plane wing can realize a combined wing design at a lower weight cost. The center wing and the rear wing of the three-plane wing form a combined wing, which improves the structural rigidity of the aircraft on the ground side and is more conducive to absorbing the impact during self-tilting landing. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] FIG1 is an axonometric view of an aircraft in level flight according to the present invention;

[0036] FIG2 is a side view of the aircraft in level flight according to the present invention;

[0037] FIG3 is a front view of the aircraft in level flight according to the present invention;

[0038] FIG4 is a top view of the aircraft in level flight according to the present invention;

[0039] FIG5 is a front view of the aircraft in a ground parking state according to the present invention;

[0040] FIG6 is a side view of the aircraft in a ground parking state according to the present invention;

[0041] FIG7 is a side view of the aircraft according to the present invention in a state of drifting in water;

[0042] FIG8 is a schematic diagram of the aircraft takeoff process proposed by the present invention.

[0043] Description of reference numerals:

[0044] 1- fuselage, 2- front wing assembly, 3- mid-wing assembly, 4- rear wing assembly, 5- wing assembly;

[0045] 21-front wing body, 22-first power group, 23-first buoy mechanism;

[0046] 231-load-bearing bracket, 232-float body, 233-telescopic member, 234-float wheel;

[0047] 31- middle wing body, 32- second power group, 33- second buoy mechanism;

[0048] 41- rear wing body, 42- third power group;

[0049] 51-Landing gear. DETAILED DESCRIPTION

[0050] The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and are not to be construed as limiting the present invention.

[0051] In response to the problems raised in the background technology, the present invention proposes the following embodiments to solve them.

[0052] Example 1

[0053] Referring to Figures 1 to 8, this embodiment proposes a three-wing, hybrid vertical take-off and landing aircraft, comprising a cantilever fuselage 1, a front wing assembly 2, a mid-wing assembly 3, and a rear wing assembly 4. The cantilever fuselage 1 is sequentially arranged along the front-to-back direction of the cantilever fuselage 1. There are two cantilever assemblies 2, two mid-wing assemblies 3, and two rear wing assemblies 4, each symmetrically arranged on either side of the cantilever fuselage 1. In a specific implementation, the cantilever fuselage 1 should also be configured as a bilaterally symmetrical structure, with the two cantilever assemblies 2 being symmetrically arranged on the left and right sides of the cantilever fuselage 1, the two mid-wing assemblies 3 being symmetrically arranged on the left and right sides of the cantilever fuselage 1, and the two rear wing assemblies 4 being symmetrically arranged on the left and right sides of the cantilever fuselage 1.

[0054] Specifically, the stilt fuselage 1 is a combination of a stilt configuration and a boat-shaped keel fuselage suitable for water takeoff and landing. Referring to Figures 5 and 6 , the bottom of the stilt fuselage 1 is configured as a boat-shaped keel, allowing it to be easily lifted from the ground while reducing resistance during takeoff from water.

[0055] The cantilever assembly 2 includes a cantilever body 21, a first power unit 22, and a first float mechanism 23. The cantilever body 21 is fixedly connected to the cantilever fuselage 1, and the first float mechanism 23 is mounted below the cantilever body 21. The function of the first float mechanism 23 is to position the aircraft at an angle conducive to takeoff, whether on the ground or on the water, when parked. That is, the front end of the aircraft is tilted upward. More specifically, when parked, the centerline of the first power unit 22 is tilted so that when the first power unit 22 is activated, it can provide an oblique forward and upward force, which can generate a torque that causes the cantilever fuselage 1 to tilt upward. The first power unit 22 is mounted on the cantilever body 21. Specifically, the first power unit 22 is rotatably mounted on the cantilever body 21 and is driven by an engine or electric motor.

[0056] The first power group 22 is installed on the front wing body 21. In the stopped state, the first power group 22 is in a tilted state to provide a moment that can tilt the tilted fuselage 1.

[0057] In specific implementation, in the ground parking state, as shown in FIG5 , the two first buoy mechanisms 23 and the belly of the cantilever fuselage 1 touch the ground simultaneously. At this time, the first buoy mechanisms 23 are in a compressed state, and the aircraft has a parking angle that is conducive to takeoff.

[0058] In the water surface parking state, as shown in FIG7 , the two first buoy mechanisms 23 and the rear portion of the cantilever fuselage 1 are immersed in water, and the aircraft has a parking angle that is favorable for takeoff. The first power group 22 of the cantilever assembly 2 is much higher than the water surface, and the propeller tips of the mid-wing assembly 3 may be immersed in water. However, the tilting process is powered by the first power group 22 on the cantilever assembly 2. During the vertical posture process, the propellers of the mid-wing assembly 3 are naturally out of water and do not affect takeoff.

[0059] As shown in Figure 8, the takeoff process is as follows: the first power unit 22 of the front wing assembly 2 generates a pulling force, causing the cantilever fuselage 1 to generate a nose-up moment around the touchdown point, causing the aircraft to "roll" along the belly curve. During this process, the cushioning of the first float mechanism 23 is released until the aircraft's attitude is vertical. Then, the propellers of the front wing assembly 2, the mid-wing assembly 3, and the rear wing assembly 4 jointly generate a pulling force to lift the aircraft off the ground. At this point, the center of gravity of the three-wing aircraft is further back than that of the two-wing cantilever aircraft, and the nose-down moment caused by the aircraft's gravity is smaller, making takeoff easier.

[0060] During the aircraft's hovering state, the power units of the front wing assembly 2, the mid-wing assembly 3, and the rear wing assembly 4 simultaneously generate thrust to balance gravity. The pitch moment is generated by the differential thrust between the front and rear wing assemblies 2 and 4, while the yaw moment is generated by the differential thrust between the left and right front and rear wing assemblies 2 and 4. The mid-wing assembly 3 does not participate in maneuvers. Rolling torque is achieved by deflecting the control surfaces on the front and rear wing assemblies 2 and 4. The mid-wing assembly 3's propellers are variable-pitch propellers, with a low pitch during takeoff and hovering to prevent propeller stall and loss of thrust.

[0061] Transition from hovering to level flight: The tension of the front wing assembly 2, the middle wing assembly 3 and the rear wing assembly 4 increases, among which the tension of the rear wing assembly 4 increases more significantly, generating a nose-down moment around the center of gravity of the aircraft and forward flight acceleration.

[0062] Level flight: the front wing assembly 2 and the rear wing assembly are closed, and the mid-wing assembly 3 provides the thrust required for flight.

[0063] Transition from level flight to hovering: The front wing assembly 2 and the rear wing assembly 4 are activated, the tension of the front wing assembly 2 is greater than the tension of the rear wing assembly 4, and the tension of the middle wing assembly 3 becomes smaller. At this time, a nose-up moment is generated around the center of gravity of the aircraft, making the aircraft attitude vertical.

[0064] The landing process is as follows: the overall pulling force of the aircraft gradually decreases, the height of the aircraft decreases until the tail landing gear of the aircraft touches the ground, the pulling force of the front wing assembly 2, the middle wing assembly 3 and the rear wing assembly 4 further decreases, and the pulling force of the front wing assembly 2 decreases at a faster rate. The aircraft slowly lowers its head under the action of gravity and rotates forward around the landing point until the first float mechanism 23 contacts the ground.

[0065] In specific implementation, in level flight, the front wing assembly 2, the middle wing assembly 3, and the rear wing assembly 4 are arranged sequentially from low to high. The front wing assembly 2, the middle wing assembly 3, and the rear wing assembly 4 are arranged sequentially from low to high, and the front wing assembly 2, the middle wing assembly 3, and the rear wing assembly 4 are substantially parallel. This arrangement enables the generation of torque by adjusting the power of the front wing assembly 2, the middle wing assembly 3, and the rear wing assembly 4, thereby achieving hovering, pitching, tilting, and vertical takeoff.

[0066] In a specific embodiment, the invention further includes a connecting wing 5 that connects the center wing assembly 3 and the rear wing assembly 4 on the same side of the cantilever fuselage 1. The connecting wing 5 is inclined outward from the front to the rear. Specifically, the connecting wing 5 connects the center wing assembly 3 and the rear wing assembly 4. Specifically, there are two connecting wings 5, one on each side of the cantilever fuselage 1, each connecting the center wing assembly 3 and the rear wing assembly 4 on the same side of the cantilever fuselage 1. More specifically, the connecting wings 5 ​​are connected to the end of the center wing assembly 3 away from the cantilever fuselage 1 and the end of the rear wing assembly 4 away from the cantilever fuselage 1.

[0067] In a specific implementation, the first buoy mechanism 23 includes a load-bearing bracket 231, a buoy body 232, a telescopic member 233 and a buoy wheel 234. Specifically, the load-bearing bracket 231 can be a shock absorber that can be compressed, and the telescopic member 233 can be a hydraulic rod or an electric telescopic rod.

[0068] The upper end of the load-bearing bracket 231 is connected to the cantilever body 21, and the lower end is connected to the pontoon body 232. The lower end of the telescopic member 233 is hinged to the pontoon wheel 234, and the upper end is hinged to the cantilever body 21. In practice, there are two first pontoon mechanisms 23, namely, one is provided on each cantilever assembly 2. The first pontoon mechanisms 23 are arranged at the end of the cantilever body 21 or at the location of the cantilever body 21 corresponding to the first power unit 22. The two first pontoon mechanisms 23 are symmetrically arranged.

[0069] Specifically, the mid-wing assembly 3 includes a mid-wing body 31 and a second power group 32; the second power group 32 is installed on the mid-wing body 31; the center of gravity of the aircraft is located on the plane where the mid-wing body 31 is located. Specifically, the position of the center of gravity of the aircraft is related to the driving method of the aircraft in level flight. Depending on the design, when the aircraft is designed to be driven only by the second power group 32 in level flight, it is best if the center of gravity of the aircraft is located on the plane where the mid-wing body 31 is located. More specifically, the center of gravity of the aircraft is located on the plane where the center lines of the two second power groups 32 are located. When the aircraft is designed to be driven by the first power group 22 and the third power group 42 in level flight, it is best if the center of gravity of the aircraft is located between the front wing body 21 and the rear wing body 41.

[0070] The mid-wing assembly 3 also includes a second pontoon mechanism 33 mounted on the bottom of the mid-wing body 31. Specifically, the second pontoon mechanism 33 shares the same structure as the first pontoon mechanism 23, namely, it also includes a load-bearing bracket 231, a pontoon body 232, a telescopic member 233, and a pontoon wheel 234. However, the first and second pontoon mechanisms 23 and 33 may have different dimensions depending on actual needs. There are also two second pontoon mechanisms 33, symmetrically arranged. Each second pontoon mechanism 33 is located at the corresponding end of the mid-wing body 31 away from the cantilever fuselage 1, or at the corresponding second power unit 32 of the mid-wing body 31. In practice, the second pontoon mechanism 33 provides buoyancy when submerged in water. When the aircraft is grounded, the second pontoon mechanism 33, along with the first pontoon mechanism 23 and the belly of the cantilever fuselage 1, maintains contact with the ground, providing stable support.

[0071] In a specific implementation, the rear wing assembly 4 includes a rear wing body 41 and a third propeller 42; the third power group 42 is mounted on the rear wing body 41. That is, each rear wing assembly 4 is provided with a third power group 42, and the two third power groups 42 are symmetrically arranged.

[0072] In a specific implementation, the propeller of the second power group 32 is a variable pitch propeller, which is in a small pitch mode during takeoff and landing and in a large pitch mode during level flight. For those skilled in the art, the variable pitch design is easy to understand and universal, and is therefore not limited to a specific type of variable pitch mechanism.

[0073] To facilitate the tilting of the cantilever fuselage 1, the distance between the front wing body 21 and the middle wing body 31 along the length of the cantilever fuselage 1 is greater than the distance between the middle wing body 31 and the rear wing body 41. In a specific implementation, when the aircraft is grounded, the belly of the cantilever fuselage 1 contacts the ground below the middle wing body 31, more specifically, below the centerline connecting the two middle wing bodies 31. Setting the distance between the front wing body 21 and the middle wing body 31 greater than the distance between the middle wing body 31 and the rear wing body 41 facilitates the first power unit 22 providing greater torque during takeoff, facilitating the tilting of the cantilever fuselage 1.

[0074] In a specific implementation, at least one of the front wing body 21, the middle wing body 31, and the rear wing body 41 is equipped with a rudder surface. Specifically, the rudder surface may be provided only on the front wing body 21, the middle wing body 31, or the rear wing body 41; or provided on two of the front wing body 21, the middle wing body 31, and the rear wing body 41; or provided on all three of the front wing body 21, the middle wing body 31, and the rear wing body 41.

[0075] In a specific implementation, in a preferred implementation manner, the lengths of the front wing body 21 , the middle wing body 31 and the rear wing body 41 increase sequentially.

[0076] Furthermore, the anhedral angle of the front wing body 21 is 6-8 degrees, specifically, the anhedral angle can be set to 6 degrees, 7 degrees, or 8 degrees. The dihedral angle of the mid-wing body 31 is 7-9 degrees, specifically, 7 degrees, 8 degrees, or 9 degrees. The anhedral angle of the rear wing body 41 is 6-8 degrees, specifically, 6 degrees, 7 degrees, or 8 degrees. In a preferred combination, the anhedral angle of the front wing body 21 is 7 degrees, the anhedral angle of the mid-wing body 31 is 8 degrees, and the anhedral angle of the rear wing body 41 is 7 degrees. This arrangement ensures the lateral stability of the aircraft.

[0077] Specifically, the sweep angle of the front wing body 21 is 7-13 degrees. In practice, the sweep angle of the front wing body 21 can be 8, 9, 10, 11, or 12 degrees, or other values. The sweep angle of the mid-wing body 31 is 15 to 25 degrees, and can be, for example, 16, 17, 18, 19, 20, 21, 22, 23, or 24 degrees.

[0078] Specifically, the power devices of the first power group and the second power group are electric power units, and the power device of the third power group is a hydrogen power unit or a fuel power unit; or, the power devices of the first power group and the second power group are hydrogen power units or fuel power units, and the power device of the third power group is an electric power unit.

[0079] For aircraft using folding propellers, during level flight, the folding propellers on the front and rear wing assemblies 2 and 4 fold backward to reduce drag. The fuel or hydrogen power unit of the mid-wing assembly 3 provides the required thrust for flight. The propellers of the second power unit 32 are variable-pitch propellers, which change to a higher pitch during level flight to improve propeller efficiency. During level flight, the pitching moment is generated by the control surfaces of the front and rear wing bodies 21 and 41, the rolling moment by the control surfaces of the front and rear wing bodies 21 and 41, and the yaw moment by the differential tension of the left and right power units of the mid-wing assembly 3. At this time, the tension line of the mid-wing assembly 3 passes through the center of gravity of the aircraft, and the tension does not generate additional pitching moment. The mid-wing assembly has its own generator, which can generate electricity to charge the battery during this phase. Therefore, the aircraft only needs to carry enough batteries for takeoff, and the power required for landing is provided by the generator during level flight. For safety reasons, the power generation function provides a sufficient power reserve.

[0080] During use, the landing process is specifically as follows: the overall tension of the aircraft gradually decreases, the aircraft's altitude decreases until the tail of the aircraft and the wing-jointed landing gear touch the ground, the front wing assembly 2, the middle wing assembly 3, and the rear wing assembly 4 are further lowered, the rate of tension reduction of the front wing assembly 2 is faster, and the aircraft slowly lowers its head under the action of gravity and rotates forward around the touchdown point. During this process, the pontoon wheel 234 of the middle wing assembly 3 touches the ground first, the load-bearing bracket 231 is compressed, and then the pontoon wheel 234 below the front wing assembly touches the ground, and the pontoon load-bearing bracket 231 is compressed. The wing-jointed 5 of the middle wing body 31 and the rear wing body 41 increases the structural rigidity of the aircraft, and is more tolerant to possible emergency and rough landings. In addition, the landing gear at the wing-jointed 5 has a large lateral width, which provides better support for the aircraft during landing.

[0081] In a specific implementation, in order to facilitate take-off and landing, the wing 5 is provided with a landing gear 51 protruding backwards, and the rear side of the landing gear 51 has an arc-shaped structure.

[0082] Example 2

[0083] This embodiment is a further improvement on the embodiment 1, and the similarities are not repeated here, and only the differences are described below.

[0084] The difference from Example 1 is that the connection method of the power unit is different. That is, in this embodiment, the first power unit is an electric power unit, and the second power unit is a hydrogen power unit or a fuel power unit.

[0085] That is, the power of the second power group 32 is provided by an electric unit, and the power of the first power group 22 and the third power group 42 is provided by a fuel power unit or a hydrogen power unit.

[0086] In this case, the center of gravity of the aircraft should also be adjusted accordingly, namely, it should be located between the plane of the front wing body 21 and the plane of the rear wing body 41. In level flight, power is provided by the first power unit 22 and the third power unit 42, while the battery is also charged during level flight. In practice, the electric power unit includes a motor regulator and a motor, which drives the propeller. The fuel power unit includes an engine, which drives the propeller. A speed reducer and other structures may be added as needed.

[0087] It should be noted that in the above embodiments, front, back, left, and right refer to the front, back, left, and right of the aircraft.

[0088] The above describes in detail the structure, features and effects of the present invention based on the embodiments shown in the drawings. The above is only a preferred embodiment of the present invention, but the scope of implementation of the present invention is not limited to what is shown in the drawings. Any changes made in accordance with the concept of the present invention, or modifications to equivalent embodiments with equivalent changes, which do not exceed the spirit covered by the description and drawings, should be within the scope of protection of the present invention.

Claims

1. A three-wing hybrid vertical take-off and landing aircraft, comprising a stilt-body fuselage (1), a front wing assembly (2), a middle wing assembly (3) and a rear wing assembly (4); the front wing assembly (2), the middle wing assembly (3) and the rear wing assembly (4) are sequentially arranged on the stilt-body fuselage (1) along the front-rear direction of the stilt-body fuselage (1); the front wing assembly (2), the middle wing assembly (3) and the rear wing assembly (4) are each two, and are symmetrically arranged on both sides of the stilt-body fuselage (1); Features: The cantilever assembly (2) comprises a cantilever body (21), a first power group (22) and a first buoy mechanism (23); the cantilever body (21) is fixedly connected to the cantilever fuselage (1), the first buoy mechanism (23) is installed below the cantilever body (21); the first power group (22) is installed on the cantilever body (21); The first power group (22) is installed on the front wing body (21). In a stopped state, the first power group (22) is in a tilted state to provide a moment for tilting the tilted fuselage (1).

2. The three-wing hybrid vertical take-off and landing aircraft according to claim 1, characterized in that: In a level flight state, the front wing assembly (2), the middle wing assembly (3) and the rear wing assembly (4) are arranged in sequence from low to high along the height direction of the fuselage.

3. The three-wing hybrid vertical take-off and landing aircraft according to claim 2, characterized in that: It comprises a connecting wing (5), wherein the connecting wing (5) connects the middle wing assembly (3) and the rear wing assembly (4) on the same side of the cantilever fuselage (1); the connecting wing (5) is inclined outwards in a direction from front to rear.

4. The three-wing hybrid vertical take-off and landing aircraft according to claim 1, characterized in that: The first buoy mechanism (23) comprises a load-bearing bracket (231), a buoy body (232), a telescopic member (233) and a buoy wheel (234); The upper end of the load-bearing bracket (231) is connected to the front wing body (21), and the lower end is connected to the pontoon body (232); the lower end of the telescopic member (233) is hinged to the pontoon wheel (234), and the upper end is hinged to the front wing body (21).

5. The three-wing hybrid vertical take-off and landing aircraft according to claim 1, characterized in that: The middle wing assembly (3) comprises a middle wing body (31) and a second power group (32); The second power group (32) is installed on the middle wing body (31); The center of gravity of the aircraft is located on the plane where the middle wing body (31) is located.

6. The three-wing hybrid vertical take-off and landing aircraft according to claim 5, characterized in that: The mid-wing assembly (3) further comprises a second buoy mechanism (33); The second buoy mechanism (33) is installed at the bottom of the middle wing body (31).

7. The three-wing hybrid vertical take-off and landing aircraft according to claim 5, characterized in that: The rear wing assembly (4) comprises a rear wing body (41) and a third power group (42); The third power group (42) is installed on the rear wing body (41).

8. The three-wing hybrid vertical take-off and landing aircraft according to claim 7, characterized in that: In the length direction of the stilt-body fuselage (1), the distance between the front wing body (21) and the middle wing body (31) is greater than the distance between the middle wing body (31) and the rear wing body (41).

9. The three-wing hybrid vertical take-off and landing aircraft according to claim 7, characterized in that: At least one of the front wing body (21), the middle wing body (31) and the rear wing body (41) is provided with a control surface.

10. The three-wing hybrid vertical take-off and landing aircraft according to claim 7, characterized in that: The lengths of the front wing body (21), the middle wing body (31) and the rear wing body (41) increase sequentially.

11. The three-wing hybrid vertical take-off and landing aircraft according to claim 7, characterized in that: The anhedral angle of the front wing body (21) is 6-8 degrees, the anhedral angle of the middle wing body (31) is 7-9 degrees, and the anhedral angle of the rear wing body (41) is 6-8 degrees.

12. The three-wing hybrid vertical take-off and landing aircraft according to claim 7, characterized in that: The sweep angle of the front wing body (21) is 7-13 degrees, the sweep angle of the middle wing body (31) is 15 to 25 degrees; the sweep angle of the rear wing body (41) is -5 to 5 degrees.

13. The three-wing hybrid vertical take-off and landing aircraft according to any one of claims 1 to 12, characterized in that: The first power group (22), the second power group (32) and the third power group (42) are all composed of a power device and a propeller; The power devices of the first power group (22) and the second power group (32) are electric power units, and the power device of the third power group (42) is a hydrogen power unit or a fuel power unit; or, the power devices of the first power group (22) and the second power group (32) are hydrogen power units or fuel power units, and the power device of the third power group (42) is an electric power unit.

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