Double-wing-layout tail-sitting type manned fixed-wing vertical take-off and landing aircraft

Abstract

The utility model discloses a double-wing-layout tail-sitting type manned fixed wing vertical take-off and landing aircraft which comprises a streamline aircraft body, a vertical tail wing, a propeller tip and propeller wing fusion duct power device, an upper row of fixed wings and a lower row of fixed wings. A manned cabin is arranged on the front side of the streamline fuselage, and a cabin cover capable of opening and closing the manned cabin is arranged at the front end of the streamline fuselage. The lower row of fixed wings are mounted on two sides of the streamline fuselage; the front end of the vertical empennage is provided with an upper row of fixed wings, and the rear end of the vertical empennage is provided with a rudder; wing tips of the double rows of fixed wings are respectively provided with a propeller tip and propeller wing fusion duct power device. The vertical take-off and landing and high-speed efficient cruise aircraft can simultaneously meet the requirements of two tasks of vertical take-off and landing and high-speed efficient cruise, the overall aerodynamic characteristic of the aircraft is good, the lift-drag ratio is high, the flight process is stable, the transition process from vertical to horizontal flight is good in stability and high in efficiency, and compared with a traditional vertical take-off and landing aircraft, the vertical take-off and landing aircraft has better hovering and horizontal flight efficiency; and better hovering anti-crosswind stability is achieved.

Description

Technical Field

[0001] The utility model relates to a tail-sitting manned fixed-wing vertical take-off and landing aircraft with a double-wing layout, belonging to the technical field of manned fixed-wing vertical take-off and landing aircraft. Background Art

[0002] Traditional aircraft are mainly divided into two categories: fixed-wing aircraft and rotary-wing aircraft. Fixed-wing aircraft have fast flight speed and high cruising efficiency, but cannot hover and need a runway for takeoff; rotary-wing aircraft can hover in the air and can take off and land vertically, but have slow flight speed and low cruising efficiency. Some existing aircraft that combine rotary and fixed wings are relatively complex in structure, with poor aerodynamic performance and poor level flight and cruising performance, especially in the process of vertical takeoff and landing to level flight mode conversion. The performance of the aircraft is low during the conversion process, which reduces the range of the aircraft. In addition, the aircraft has poor stability during the mode conversion process, poor stability when encountering crosswinds during vertical takeoff and landing, weak crosswind resistance, and the overall design is not novel enough.

[0003] The four rotors of a quadcopter cancel each other out, so there is no need to provide additional torque to balance the aircraft. The aircraft attitude is adjusted only by adjusting the speed, and there is no need for a propeller pitch adjustment device, which makes the design simpler. The quadcopter vertical take-off and landing aircraft has multiple rotors, so it has a larger load capacity, and the blades can also be made smaller, making it easy to miniaturize. It is precisely because of these many advantages that quadcopters have broad application prospects and research value.

[0004] However, there is currently a lack of manned aircraft that integrates the rotors of a quad-rotor with fixed wings. In view of this, the present utility model is proposed. Summary of the invention

[0005] The utility model provides a tail-sitting manned fixed-wing vertical take-off and landing aircraft with a double-wing layout, which provides effective hardware support for realizing vertical take-off and landing and high-speed and efficient cruising through the ingenious combination of a double-wing layout and a propeller-wing fusion ducted power device.

[0006] The technical scheme of the utility model is: a tail-sitting manned fixed-wing vertical take-off and landing aircraft with a double-wing layout, comprising a streamlined fuselage 2, double-row fixed wings, a vertical tail 11, and a blade tip-rotor-wing fusion ducted power device; the double-row fixed wings include an upper row of fixed wings 13 located above the center of gravity of the streamlined fuselage 2, and a lower row of fixed wings 3 located below the center of gravity of the streamlined fuselage 2; the front side of the streamlined fuselage 2 is a manned cabin, and the front end of the streamlined fuselage 2 is provided with a cabin cover 1 that can open and close the manned cabin; the lower row of fixed wings 3 are installed on both sides of the streamlined fuselage 2; the vertical tail 11 is fixed to the upper part of the streamlined fuselage 2, the upper row of fixed wings 13 are installed at the front end of the vertical tail 11, and the rudder 10 is installed at the rear end of the vertical tail 11; the wingtips of the double-row fixed wings are all equipped with the wingtip-rotor-wing fusion ducted power device.

[0007] The upper row of fixed wings 13 and the lower row of fixed wings 3 are both swept wings, and the two are arranged in parallel.

[0008] The blade tip and wing integrated ducted power device includes a winglet 4, a duct 5, an aileron 6, a motor compartment 7, a propeller 8, and a support frame 9. The wingtips of the upper row fixed wing 13 and the lower row fixed wing 3 are both installed with the motor compartment 7, and the propeller 8 is installed at the rear end of the motor compartment 7; the winglet 4 is installed at the outer end of the motor compartment 7, one end of the winglet 4 is fixedly connected to the motor compartment 7, and the other end of the winglet 4 is fixedly connected to the inner wall of the duct 5; the duct 5 is coaxially arranged with the propeller 8, and the support frame 9 for installing the aileron 6 is provided at the rear end of the outer wall of the duct 5, and a duct reinforcement rib 12 is formed at the connection between the support frame 9 and the outer wall of the duct 5 close to the streamlined fuselage 2.

[0009] An extension portion is provided at one end of the duct reinforcement rib 12 away from the duct 5 , and the extension portions of the four duct reinforcement ribs 12 form a four-point support.

[0010] The utility model also comprises a landing gear installed at the lower part of the streamlined fuselage 2.

[0011] The beneficial effects of the utility model are:

[0012] The utility model can simultaneously achieve the two mission requirements of vertical take-off and landing and high-speed and efficient cruising. The overall aerodynamic characteristics of the aircraft are good, the lift-to-drag ratio is high, the flight process is smooth, and the transition process from vertical to level flight is stable and efficient. Compared with traditional vertical take-off and landing aircraft, it has better hovering and level flight efficiency, and has better hovering and crosswind stability. Specifically: First, the utility model adopts a double-row fixed-wing design, which reduces the span of the fixed wings to meet the national standard for one-way lane parking while ensuring sufficient power for manning; the upper and lower rows of fixed wings in the double-row fixed wings are arranged in parallel, one is located below the center of gravity, and the other is located above the center of gravity, and the force distribution is uniform, which can improve the stability of the aircraft. Second, the center of the wingtip propeller-wing fusion ducted power device of the utility model is fixed to the wingtip of the fixed wing, realizing the fusion of multiple components. By fully considering the aerodynamic optimization of propeller-wing fusion and the reasonable allocation of the positions of various aerodynamic components, the stability and maneuverability of the aircraft in various flight states can be met, and the aerodynamic performance of the aircraft can also be greatly improved. In addition, the rotation direction of the propeller is opposite to the rotation direction of the fixed-wing wingtip vortex, which can resist the wingtip vortex. At the same time, the propeller wake is uniform and vortex-free through the internal propeller-wing fusion characteristics, and the wake interacts with the aileron, so that the aileron can better exert its control characteristics under the action of the ideal wake. Third, the utility model has four wingtip propeller-wing fusion ducted power devices, with high safety redundancy. Even if all four wingtip propeller-wing fusion ducted power devices fail, the lift generated by the fixed wing can be used for gliding. In case of emergency landing, the landing gear can help the aircraft to achieve safe forced landing in fixed-wing mode, and the fuselage size design allows the aircraft to make an forced landing on a national standard one-way lane, ensuring the safety of the aircraft. Fourth, the fuselage of the utility model is designed in a form of scaling from front to back, which ensures that the cabin has sufficient manned space, ensures the streamline of the fuselage, and optimizes the aerodynamic performance. Fifth, the utility model fully utilizes the propeller-wing fusion characteristics through the rear-positioned propeller and the winglet design in the duct, which can effectively improve the pulling force generated by the propeller, and the design of the winglet can rectify the airflow inhaled by the propeller, so that the propeller wake is non-rotating and uniform, which is conducive to improving the maneuverability of the aileron and improving flight efficiency; the utility model optimizes the aerodynamic characteristics of the coupling of the power propeller and the fixed wing through ingenious design, and realizes the fusion of the fixed wing and the rotor more efficiently. Sixth, the angle between the fixed wing and the longitudinal axis of the fuselage of the utility model is always a favorable angle of attack for the fixed wing. When the aircraft is in the three modes of vertical to level flight, level flight, and level flight to vertical flight, the longitudinal axis of the aircraft fuselage and the relative incoming flow direction are always kept the same, and the fixed wing of the aircraft is always kept in a favorable angle of attack state during flight. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a schematic diagram of the three-dimensional structure of the whole aircraft in fixed-wing mode. Figure 1 ;

[0014] Figure 2This is a schematic diagram of the three-dimensional structure of the whole aircraft in fixed-wing mode. Figure 2 ;

[0015] Figure 3 It is the front view of the utility model;

[0016] Figure 4 This is a top view of the aircraft in fixed-wing mode.

[0017] Figure 5 To reflect the side view during vertical take-off and vertical landing;

[0018] Figure 6 To reflect the side view during the takeoff-level flight transition;

[0019] Figure 7 To show the side view of the whole aircraft during level flight;

[0020] Figure 8 To show the rear view of the vertical take-off and landing aircraft during level flight;

[0021] Fig. 9 A schematic diagram showing the definition of the coordinate system;

[0022] The numbers in the figure are: 1-canopy, 2-streamlined fuselage, 3-lower row fixed wing, 4-wingtip, 5-duct, 6-aileron, 7-propeller motor compartment, 8-propeller, 9-support frame, 10-rudder, 11-vertical tail, 12-duct reinforcement rib, 13-upper row fixed wing. DETAILED DESCRIPTION

[0023] The utility model is further described below in conjunction with the accompanying drawings and embodiments, but the content of the utility model is not limited to the described scope.

[0024] Example 1: Figure 1-9 As shown, a tail-sitting manned fixed-wing vertical take-off and landing aircraft with a double-wing layout comprises a streamlined fuselage 2, double-row fixed wings, a vertical tail 11, and a blade tip-rotor-wing fusion ducted power device; the double-row fixed wings comprise an upper row of fixed wings 13 located above the center of gravity of the streamlined fuselage 2, and a lower row of fixed wings 3 located below the center of gravity of the streamlined fuselage 2; the front side of the streamlined fuselage 2 is a manned cabin, and the front end of the streamlined fuselage 2 is provided with a cabin cover 1 that can open and close the manned cabin to meet the needs of single-pilot flight; the lower row of fixed wings 3 are installed on both sides of the streamlined fuselage 2; the vertical tail 11 is fixed to the upper part of the streamlined fuselage 2, the upper row of fixed wings 13 are installed at the front end of the vertical tail 11, and the rudder 10 is installed at the rear end of the vertical tail 11 for aircraft yaw adjustment; the wingtips of the double-row fixed wings are all equipped with the wingtip-rotor-wing fusion ducted power device.

[0025] Furthermore, it also includes a landing gear installed at the lower part of the streamlined fuselage 2. The landing gear is installed under the fuselage and can be composed of a wing-shaped support rod, a wheel well, and a tire. It is retracted to the belly cabin of the aircraft when the aircraft is flying normally, and is lowered when the aircraft needs to make an emergency landing, so that the aircraft can make an emergency landing in a fixed-wing mode. The wheel well and the wing-shaped support rod are designed to be streamlined, which can reduce air resistance. At the same time, after the power unit mechanism fails, the landing gear can be lowered to achieve a landing similar to that of a fixed-wing aircraft. This design improves the safety of the aircraft.

[0026] Furthermore, the blade tip and wing integrated ducted power device includes a winglet 4, a duct 5, an aileron 6, a motor compartment 7, a propeller 8, and a support frame 9. The wingtips of the upper row fixed wing 13 and the lower row fixed wing 3 are both installed with the motor compartment 7, and the propeller 8 is installed at the rear end of the motor compartment 7; the winglet 4 is installed at the outer end of the motor compartment 7, one end of the winglet 4 is fixedly connected to the motor compartment 7, and the other end of the winglet 4 is fixedly connected to the inner wall of the duct 5; the duct 5 is coaxially arranged with the propeller 8, and the support frame 9 for installing the aileron 6 is provided at the rear end of the outer wall of the duct 5, and a duct reinforcement rib 12 is formed at the connection between the support frame 9 and the outer wall of the duct 5 close to the streamlined fuselage 2.

[0027] Furthermore, an extension portion is provided at one end of the duct reinforcement rib 12 away from the duct 5 , and the extension portions of the four duct reinforcement ribs 12 form a four-point support.

[0028] Furthermore, the support frame 9 is H-shaped, one end of the first vertical rod is attached to the outer wall of the duct and connected to the upper row fixed wing 13 / the lower row fixed wing 3 as a reinforcing rib at the connection, the second vertical rod is connected to the duct shell at one end on the same side as the first vertical rod, the other ends of the two tightening rods are free ends, the rear end of the cross bar is used to install the aileron 6 (a servo is installed inside the support frame 9 to control the rotation of the aileron), and the width of the aileron 6 is flush with the duct 5. The rear aileron can use the wake of the propeller 8 to roll the aircraft. This assembly method can fix the duct to make the duct structure more stable, and can also install the aileron 6 behind the propeller 8, and can also install a servo inside to control the aileron.

[0029] Furthermore, the streamlined fuselage 2 is a streamlined single-seat fuselage, which converges rapidly to the tail at the highest point, and the cabin is placed between the nose and the highest point to meet the space requirements for single-person driving; the lower part of the streamlined fuselage 2 is slightly curved and extends to the tail; the width of the streamlined fuselage 2 does not change from the head to the widest point. It is streamlined and lightweight in design while meeting the strength of the fuselage, reducing its own gravity and optimizing aerodynamic performance.

[0030] Furthermore, the vertical tail 11 is placed above the center of gravity of the aircraft, and the upper row of fixed wings 13 are installed at the front end thereof, which can fix the upper row of fixed wings 13 without destroying the streamline of the fuselage; the part above the upper row of fixed wings 13 extends out a rudder, which can control the yaw of the aircraft. The vertical tail 11 is a common tail, and a rudder 10 is arranged on the rear side, and is fixedly connected to the rear half of the fuselage. When parked, four support rods support the aircraft at four points.

[0031] Furthermore, the lift centers of the upper row fixed wings 13 and the lower row fixed wings 3 are on the same plumb plane as the center of gravity of the fuselage 2; the lower row fixed wings 3 are fixed to the lower part of the fuselage at one quarter of the height of the fuselage, the upper row fixed wings 10 are fixed to the front end of the vertical tail 11 and are parallel to the lower row fixed wings 3, and both rows of fixed wings are swept wings.

[0032] Furthermore, two winglets 4 are installed in each of the blade tip and wing fused duct power devices, and the two are symmetrical about the wing plane. They serve as a fulcrum for supporting the duct shell respectively, and can support and stabilize the duct 5 while resisting the wingtip vortex; the plane where the winglet 4 is located has an angle of 60 degrees with the horizontal plane. It is installed at the front end of the propeller to rectify the incoming flow, so that the wake of the propeller 8 is uniform, vortex-free and more stable.

[0033] Furthermore, the rotation direction of the propeller 8 is such that when viewed from the tail to the nose, the two propellers 8 on the left rotate counterclockwise, while the two propellers 8 on the right rotate clockwise, thereby ensuring that the rotation direction of the propellers on the left and right sides is opposite to the rotation direction of the wingtip vortex of the fixed wing; the above-mentioned rotation direction setting can not only balance the torque caused by the rotation, but also inhibit the wingtip vortex of the fixed wing, and at the same time, the propeller wake is made uniform and vortex-free through the internal propeller-wing fusion characteristics, and the wake interacts with the aileron, so that the aileron can better exert its control characteristics under the action of the ideal wake.

[0034] Furthermore, the aircraft is bilaterally symmetrical and is a plane-symmetrical aircraft, the planes of symmetry are the longitudinal axis and the vertical axis, and the center of gravity of the aircraft is located in the middle of the fuselage. The lift center of the upper row fixed wing 13 is located above the center of gravity, providing a nose-down moment; the lift center of the lower row fixed wing 3 is located below the center of gravity, providing a nose-up moment. The line connecting the lift center of the upper and lower rows of fixed wings and the center of gravity of the fuselage is parallel to the longitudinal axis of the fuselage and perpendicular to the symmetry plane of the horizontal axis of the longitudinal axis of the aircraft. The propeller tip wing fusion duct power device on the upper and lower rows of fixed wings provides a nose-up or nose-down moment by changing the torque difference generated by the rotation speed. The propeller rotation speeds on the same row of fixed wings are opposite to offset the torque, and the rotation speed direction is opposite to the wingtip vortex, thereby offsetting the wingtip vortex.

[0035] The entire process of tilting is divided into five processes. Taking the aircraft of the utility model as an example, the specific working principle is described as follows:

[0036] The horizontal axis, vertical axis and vertical axis are specifically defined in the attached Fig. 9In the figure, the center of gravity of the aircraft is taken as the origin, and the X-axis is forward along the longitudinal symmetry plane of the aircraft as the positive direction, which is called the longitudinal axis; the Z-axis is perpendicular to the longitudinal axis in the longitudinal symmetry plane of the aircraft, with the upward direction as the positive direction, which is called the vertical axis; the Y-axis is perpendicular to the longitudinal symmetry plane, with the right direction as the positive direction, which is called the horizontal axis. The positive and negative directions of the rotation of the aircraft around each axis are determined in accordance with the right-hand rule. It should be noted that the words "front", "rear", "left", "right", "up" and "down" used in the following description refer to the directions in the accompanying drawings, where "front" represents the positive direction of the longitudinal axis of the aircraft, "rear" represents the negative direction of the longitudinal axis of the aircraft, "right" represents the positive direction of the horizontal axis of the aircraft, "left" represents the negative direction of the horizontal axis of the aircraft, "up" represents the positive direction of the vertical axis of the aircraft, and "down" represents the negative direction of the vertical axis of the aircraft. The clockwise and counterclockwise directions around each axis are defined by the right-hand rule. The direction that complies with the right-hand rule is "clockwise", and the opposite is "counterclockwise".

[0037] Vertical take-off process: Figure 5As shown, in this process, the aircraft stands vertically on the ground, and the four support rods on the aircraft support the fuselage at four points, and the rotation axis of the propeller is parallel to the longitudinal axis of the fuselage. The forces on the aircraft include: the vertical upward force generated by the four propellers, the gravity on the aircraft, and the horizontal force generated by the double-row fixed wing. The moments on the aircraft include: the nose-up moment and nose-down moment generated by the speed difference between the upper and lower rows of propellers, the yaw moment generated by the rudder on the vertical tail, and the roll moment generated by the differential deflection of the ailerons on the left and right sides. When the aircraft takes off, the propeller 8 starts to rotate to provide lift, and the lift is greater than the gravity to make the entire aircraft leave the ground. After the aircraft reaches a certain height, the pulling force is reduced to balance the lift and gravity, and it hovers in the air. Since the aircraft is symmetrical on the left and right, the roll moment and the yaw moment cancel each other out. In the whole process, the nose-up moment generated by the front lower row propeller 8 and the nose-down moment generated by the upper row propeller are guaranteed to be equal, that is, the pitch moment balance of the aircraft is guaranteed. When the aircraft is hovering and is disturbed by crosswinds in any direction, it can be decomposed into vertical upward, downward, left, right, forward, and backward crosswinds. Therefore, only the upward, downward, left, right, forward, and backward anti-crosswind methods are considered for balancing operations. That is, when the aircraft is affected by vertical backward crosswinds, it will tend to move backward. At this time, the speed of the upper propeller can be increased and the speed of the lower propeller can be reduced to make the aircraft produce a downward attitude change. At this time, the horizontal force generated by the four propeller pulls resists the front crosswind force, and the upward force generated by the four propeller pulls resists the aircraft's own gravity. The aircraft maintains torque balance in this state by adjusting the torque. When the aircraft is affected by the vertical forward crosswind, it will tend to move forward. At this time, the speed of the upper row of propellers 8 can be reduced by increasing the speed of the lower row of propellers 8, so that the aircraft will have an upward attitude change. At this time, the horizontal component force generated by the four propeller pulling forces resists the rear crosswind force, and the upward component force generated by the four propeller pulling forces resists the aircraft's own gravity, and the aircraft is kept in torque balance in this state by adjusting the torque. When the aircraft is affected by the vertical left crosswind in the hovering state, the aircraft will tend to move to the left. At this time, by adjusting the differential of the aileron, the aircraft will produce a rolling motion in the corresponding direction, and the left crosswind will be transformed into a backward crosswind, and a balancing operation can be performed. When the aircraft is affected by the vertical right crosswind in the hovering state, the aircraft will tend to move to the right. At this time, by adjusting the differential of the aileron, the aircraft will produce a rolling motion in the corresponding direction, and the right crosswind will be transformed into a backward crosswind, and a balancing operation can be performed. When resisting the crosswinds on the left and right sides, it is necessary to keep the lift and gravity of the aircraft balanced, and balance the aircraft torque by adjusting the torque. When the aircraft is affected by vertically upward and vertically downward crosswinds, the gravity and lift are unbalanced, and the hovering state of the aircraft will change. The pulling force can be changed by changing the speed of the propeller 8 to achieve the balance of the aircraft, and the torque of the aircraft can be balanced by adjusting the torque.

[0038] Vertical takeoff-level flight transition process: Figure 6 As shown, the aircraft enters the tilt transition process from the hovering state. At this time, the forces on the aircraft include: the force generated by the propeller 8 parallel to the longitudinal axis of the fuselage 2, the force generated by the fixed wing parallel to the vertical axis of the fuselage, the gravity of the aircraft, the lift generated by the upper and lower rows of fixed wings on the fuselage, and the resistance generated by the fuselage and the fixed wing. The moments on the aircraft include: the nose-up moment or nose-down moment generated by the difference between the pulling force of the upper row of propellers 8 and the pulling force of the lower row of propellers, the adjustable yaw moment generated by the rudder 10, which is convenient for controlling the overall yaw movement of the aircraft, and the rolling moment and adjustable pitch moment generated by the aileron 6. During the tilting process, the pulling force of the upper propeller 8 is increased, and the pulling force of the lower propeller 8 is reduced, generating a nose-down moment, causing the aircraft to pitch down. After the tilting begins, the propeller thrust generates a positive component along the longitudinal axis of the ground system, allowing the aircraft to have a forward flight speed along the longitudinal axis of the ground system. The propeller 8 thrust generates a positive component along the vertical axis of the ground system, allowing the aircraft to have an ascending speed along the vertical axis of the ground system. The sum of the forward flight speed and the ascending speed is the incoming flow speed, and the incoming flow speed is parallel to the longitudinal axis of the fuselage. Since the fixed-wing installation angle and the longitudinal axis of the fuselage are at a favorable angle of attack, it is ensured that the fixed-wing of the aircraft always maintains a favorable angle of attack when flying. During the tilting process, the propeller 8 and aileron 6 as a whole generate a pitching moment that causes the aircraft to lower its head, causing the aircraft to lower its head. During the tilting process of the aircraft, since the aircraft is symmetrical on the left and right, the rolling moment and yaw moment on the left and right sides of the aircraft cancel each other out. As the aircraft gradually tilts to a horizontal position as a whole, such as Figure 4 As shown in the figure, the ground system longitudinal axis speed of the aircraft increases continuously during the tilting process, and the aircraft enters the fixed-wing flight mode. During the tilting process, the aircraft speed direction is kept consistent with the longitudinal axis of the fuselage.

[0039] Level flight process: Figure 7As shown, during this process, the forces acting on the aircraft include: the forward pulling force generated by the upper and lower rows of four propellers 8, the lift generated by the upper and lower rows of fixed wings, the drag generated by the aircraft as a whole, and the gravity acting on the aircraft. The moments acting on the aircraft include: the nose-up moment or nose-down moment generated by the differential of the upper and lower rows of propellers on the fuselage, the rolling moment provided by the aileron 6, and the yaw moment provided by the rudder of the vertical tail 11. In the level flight state, the lift of the aircraft is balanced with the gravity it is subjected to, and the thrust is balanced with the drag. Since the aircraft is symmetrical on the left and right, the yaw and roll moments on the left and right sides of the aircraft cancel each other out. When the nose-up moment of the aircraft is equal to the nose-down moment, the pitch moment of the aircraft is balanced. When the aircraft is subject to pitch disturbance, the aircraft's angle of attack changes, and the lift of the upper and lower rows of fixed wings and the fuselage changes, that is, additional lift is generated. The additional lift will generate a torque opposite to the disturbance direction to ensure pitch stability. When the aircraft cannot return to a balanced state by itself, the speed difference of the upper and lower rows of propellers 8 can also be controlled to adjust the horizontal pulling force difference above and below the center of gravity of the aircraft to ensure pitch stability. In addition, the upper and lower ailerons can be controlled to differentially deflect to assist in adjusting the pitch attitude. When the aircraft is subject to roll disturbance, the lift of the upper and lower rows of fixed wings on the left and right sides of the fuselage is unbalanced, which can generate a stabilizing torque opposite to the rolling direction. Since the vertical tail 11 is located above and behind the center of gravity, the side force generated will form a stabilizing torque opposite to the rolling direction on the center of gravity, so that the aircraft maintains roll stability. When the aircraft cannot return to a balanced state by itself, the ailerons 6 on the left and right sides of the fuselage can also be controlled to deflect to achieve roll balance. In addition, by manipulating the deflection of the left and right ailerons 6, the different lift differences generated by the two ailerons 6 on the left and the two ailerons 6 on the right will generate a torque that drives the aircraft to roll, causing the aircraft to roll. When the aircraft is subject to lateral disturbances, the vertical tail 11 will be affected by the airflow and will generate a lateral force in the same direction as the yaw direction, causing the aircraft to generate a stabilizing torque opposite to the yaw direction. In addition, when the aircraft is subject to heading disturbances and sideslips, the fixed wing of the aircraft can use a sweep angle, and the existence of the sweep angle will increase the resistance of the front wing on the sideslipping side and reduce the resistance on the other side, thereby generating a yaw stabilizing torque. When the aircraft cannot return to a balanced state by itself, the rudder 10 can also be adjusted to ensure yaw stability. In addition, by manipulating the deflection of the rudder 10, a yaw torque that drives the aircraft to yaw can be generated, causing the aircraft to yaw. When the aircraft is affected by wind during level flight, the wind speed direction can be decomposed into the left and right side crosswinds and the wind in the symmetry plane for analysis. Regarding the effect of the wind in the symmetry plane, due to Therefore, when the aircraft is affected by the wind in the plane of symmetry, the aircraft needs to adjust the angle of attack of the aircraft according to the size and direction of the relative airspeed, so that the aircraft changes its pitch angle, prevents the aircraft from insufficient lift due to too small an angle of attack or stalling due to too large an angle of attack, and enables the aircraft to maintain a favorable angle of attack. When affected by the wind in the plane of symmetry, since changing the angle of attack of the aircraft requires changing the differential speed of the upper and lower rows of propellers 8 of the aircraft, it is necessary to re-ensure the force balance of the aircraft after adjusting the angle of attack when affected by the wind, and achieve torque balance by adjusting the torque. When affected by a vertical left crosswind, the aircraft will tend to move to the left. At this time, the two ailerons on the left side of the aircraft can be controlled downward, and the two ailerons on the right side can be controlled upward, so that the aircraft will have a rolling angle to the right. At this time, the upper and lower rows of fixed wings of the aircraft will produce a right component force to resist the crosswind. Similarly, when the aircraft is affected by a vertical right crosswind, the aircraft will tend to move to the right. At this time, the two ailerons 6 on the left side of the aircraft can be controlled to move upward and the two ailerons 6 on the right side can be controlled to move downward, so that the aircraft will roll to the left. The upper and lower rows of fixed wings of the aircraft will generate a left component force to resist the crosswind. When resisting the crosswind on both sides, it is necessary to maintain the balance between the lift and gravity and the thrust and drag of the aircraft, and balance the aircraft torque by adjusting the torque.

[0040] Level flight-vertical landing transition process: Figure 6 As shown, the forces on the aircraft at this time include: the force along the longitudinal axis generated by the propeller 8, the lift generated by the fixed wing and the gravity on the aircraft. The moments on the aircraft include: the nose-up moment generated by the left and right propellers 8 on the lower row, the nose-down moment generated by the left and right propellers 8 on the upper row, the yaw moment generated by the rudder 10 and the rolling moment generated by the aileron differential. During the tilting process, the rotation speed of the upper row propeller 8 is first reduced while the rotation speed of the lower row propeller 8 is increased, so that the nose-down moment is reduced and the nose-up moment is increased. The overall nose-down moment of the aircraft is less than the nose-up moment. The aircraft raises its head, and at the same time, the rotation speed of the four propellers 8 is continuously reduced to reduce its speed along the longitudinal axis of the fuselage. Due to the nose-up moment, the longitudinal axis of the aircraft fuselage is facing upward, and the pulling force generated by the propeller 8 is the same as the gravity of the aircraft, so as to achieve the purpose of hovering. During the tilting process, since the aircraft is symmetrical on both sides, the rolling moment and yaw moment on the left and right sides are equal to achieve rolling and yaw balance. By ensuring that the nose-up moment and the nose-down moment are equal during the entire tilting process, the pitch moment balance of the aircraft can be ensured.

[0041] Landing process: Figure 5As shown, after the aircraft tilts to a vertical state as a whole, the propeller 8 still keeps rotating, and the aircraft stabilizes in a hovering state first, and then begins to land slowly. During the landing process, the aircraft is subjected to the following forces: the gravity of the fuselage 2, the pulling force generated by the propeller 8 along the longitudinal axis of the fuselage, and the rotation speed of the four propellers 8 can be controlled so that the lift of the aircraft is less than the gravity, so that the entire aircraft lands slowly; the torques subjected to the aircraft are: the speed difference between the upper and lower rows of propellers 8 and the nose-up or nose-down torque generated by the aileron 6, and the rolling torque generated by the propellers 8 on the left and right sides of the fuselage. Since the left and right sides of the aircraft are symmetrical and have the same rotation speed, the rolling torque and yaw torque on the left and right sides of the aircraft cancel each other out. The nose-up torque and the nose-down torque are equal during the entire landing process, which can ensure that the pitch moment of the aircraft is balanced. The solutions for maintaining the balance of the aircraft after being disturbed by wind in this process are the same as those in the vertical take-off process, and will not be repeated here.

[0042] It should be noted that the side view of the aircraft when the entire aircraft is stationary is also as follows. Figure 5 shown.

[0043] It can be known from the application of the above technical scheme that the aerodynamic centers of the double-row fixed wings are respectively placed above and below the same vertical plane of the center of gravity of the fuselage, which can improve the flight pitch stability of the aircraft. At the same time, the height difference between the upper row fixed wing 13 and the lower row fixed wing 3 in the vertical axis direction can reduce the airflow interference between each propeller 8 group, reduce the interference resistance caused by the interaction of airflow, and improve the cruising range; the four blade tip wing fusion ducted power devices have the same structure, all including winglets 4, propellers 8, etc. In the level flight stage, the upper row fixed wing 13 and the lower row fixed wing 3 are on the same vertical plane, so that the pitch operation of the fuselage can be achieved through the speed difference between the upper and lower ducts in the fixed wing mode. The blade tip wing fusion ducted power device can improve the aerodynamic efficiency due to the blade fusion design of the propeller 8, winglet 4, and fixed wing part, and can reduce the induced drag caused by the wingtip vortex, reduce the damage of the circumferential flow to the lift, and improve the lift-to-drag ratio, so as to achieve the purpose of increasing lift and reducing drag.

[0044] The specific implementation modes of the present invention have been described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above implementation modes, and various changes can be made within the knowledge scope of ordinary technicians in the field without departing from the purpose of the present invention.

Claims

1. A tail-sitting manned fixed-wing vertical take-off and landing aircraft with a biplane layout, characterized in that: The invention comprises a streamlined fuselage (2), a double-row fixed wing, a vertical tail (11), and a blade tip-blade fused ducted power device; the double-row fixed wing comprises an upper row fixed wing (13) located above the center of gravity of the streamlined fuselage (2), and a lower row fixed wing (3) located below the center of gravity of the streamlined fuselage (2); the front side of the streamlined fuselage (2) is a manned cabin, and the front end of the streamlined fuselage (2) is provided with a cabin cover (1) capable of opening and closing the manned cabin; the lower row fixed wing (3) is mounted on both sides of the streamlined fuselage (2); the vertical tail (11) is fixed to the upper part of the streamlined fuselage (2), the upper row fixed wing (13) is mounted at the front end of the vertical tail (11), and a rudder (10) is mounted at the rear end of the vertical tail (11); and the blade tip-blade fused ducted power device is mounted on the wingtips of the double-row fixed wings.

2. The tail-sitting manned fixed-wing vertical take-off and landing aircraft according to claim 1, characterized in that: The upper row of fixed wings (13) and the lower row of fixed wings (3) both adopt swept wings, and the two are arranged in parallel.

3. The tail-sitting manned fixed-wing vertical take-off and landing aircraft according to claim 1, characterized in that: The blade tip and wing fused ducted power device comprises a winglet (4), a duct (5), an aileron (6), a motor compartment (7), a propeller (8), and a support frame (9); the motor compartment (7) is installed at the wingtips of the upper row fixed wing (13) and the lower row fixed wing (3); the propeller (8) is installed at the rear end of the motor compartment (7); the winglet (4) is installed at the outer end of the motor compartment (7); one end of the winglet (4) is fixedly connected to the motor compartment (7); the other end of the winglet (4) is fixedly connected to the inner wall of the duct (5); the duct (5) and the propeller (8) are coaxially arranged; the support frame (9) for installing the aileron (6) is provided at the rear end of the outer wall of the duct (5); and a duct reinforcing rib (12) is formed at the connection between the support frame (9) and the outer wall of the duct (5) close to the streamlined fuselage (2).

4. The tail-sitting manned fixed-wing vertical take-off and landing aircraft according to claim 3, characterized in that: An extension portion is provided at one end of the duct reinforcement rib (12) away from the duct (5), and the extension portions of the four duct reinforcement ribs (12) form a four-point support.

5. The tail-sitting manned fixed-wing vertical take-off and landing aircraft according to claim 1, characterized in that: It also includes a landing gear installed at the lower part of the streamlined fuselage (2).

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