CN-122009479-A - Aircraft structure

Abstract

An aircraft structure comprising a fuselage, first and second front wings mounted to and/or extending from opposite sides of the fuselage, a continuous rear span defining first and second rear wings and a central stationary connection, a first wing connection member extending between the first and second front wings, a second wing connection member extending between the second front wing and the second rear wing, wherein the rear span is supported by a centrally located V-shaped tail joint defined by first and second angularly inclined arms, first and second electric motors each having a rotor wing mounted to each wing, each rotor wing pivoting between a first configuration for vertical flight and a second configuration for forward flight.

Inventors

• A. D. mole
• A. L. Swallow

Assignees

• 艾姆索创新私人有限公司

Dates

Publication Date

20260512

Application Date

20210917

Priority Date

20200918

Claims (8)

1. 1. An aircraft structure comprising: A body; First and second front wings mounted to and/or extending from opposite sides of the fuselage, A continuous rear span defining first and second rear wings and a central stationary connection portion, A first wing connection member extending between the first front wing and the first rear wing, A second wing connection member extending between the second front wing and the second rear wing, and A first electric motor and a second electric motor, each having a rotor mounted to each wing, each rotor pivoting between a first configuration for vertical flight and a second configuration for forward flight, Wherein the aft span is supported by a centrally located V-tail joint defined by a first angled arm and a second angled arm, and Wherein the first and second angled arms are joined at a proximal lower end, and the proximal lower end is mounted between a rear bulkhead and a tail cone of the fuselage such that the proximal lower end is built into an interior cavity formed by the rear bulkhead and the tail cone.
2. 2. The aircraft structure of claim 1, wherein each arm has a distal exposed portion extending above the tail cone.
3. 3. The aircraft structure of claim 2, wherein the distal exposed portion has a aerodynamic fairing on a leading edge.
4. 4. The aircraft structure of claim 3, wherein a pneumatic shield is positioned at a junction where the distal exposed portion of each arm extends upwardly beyond the fuselage.
5. 5. The aircraft structure of any one of claims 1 to 4, wherein the first and second angled arms are joined at the proximal lower end by a vertically extending mount to form a Y-shaped tail support.
6. 6. The aircraft structure of any one of claims 1 to 4, wherein the span ratio is defined as the ratio of: the span ratio of the aircraft structure is in the range of about 0.088 to 0.105.
7. 7. The aircraft structure of any one of claims 1-4, wherein the first and second angularly inclined arms are angularly offset relative to each other at an angle of about 19-26 degrees.
8. 8. The aircraft structure of any one of claims 1 to 4, wherein each wing has a fixed leading edge and a pivoting trailing control surface.

Description

Aircraft structure The application is a divisional application of China patent application 202180063941.8 with the name of aircraft structure, which is applied for Ai Msuo Innovation private Co-Ltd, with the application date of 2021, 9 and 17. Technical Field The present disclosure relates to an aircraft structure. In particular, the present invention relates to an improved structure for a box wing aircraft, and more particularly to an improved structure for a vertical take-off and landing (VTOL) box wing aircraft. However, it should be understood that the improved structures disclosed herein may be applied to other aircraft types. Background Aeroelasticity involves the interaction between inertial, elastic and aerodynamic forces acting on an elastic body exposed to a fluid flow. One particular aspect of aeroelasticity is known as "chatter". Flutter involves unconstrained vibrations that can lead to destruction of the aircraft. Flutter must be taken into account when designing aircraft structures. Chatter involves dynamic instability of the elastic structure within the fluid flow caused by feedback between deflection of the body and the force applied by the fluid flow. In a linear system, a "chatter point" is a point at which the structure undergoes simple harmonic motion-zero net damping-and thus any further reduction in net damping will result in self-oscillation and eventual failure. The aerodynamic-exposed structures, including the wings and airfoils (aerofoil), must be carefully designed within known parameters to avoid flutter. Changing the mass distribution of an aircraft or the stiffness of one component may induce flutter in a pneumatic component that is clearly irrelevant. Flutter may develop uncontrollably and cause serious damage or destruction of the aircraft. The variation in mass distribution and local structural stiffness can be used to vary the aircraft flight speed up to the flutter point. In practice, the aircraft must be designed in such a way that the aircraft does not run at or near the flutter point. However, designing an aircraft to avoid catastrophic failure due to flutter can be challenging, as small changes in one parameter can have a substantial impact on the manner in which the aircraft structure reacts at different speeds and conditions. One approach for reducing the risk of a flutter point failure is to limit the maximum flight speed to a level significantly below the speed at which the flutter point will be encountered. However, this may be impractical, and in practice this may adversely affect the commercial viability of a given aircraft design by undesirably limiting maximum speed. Another measure to reduce the risk of an aircraft running at or near flutter speeds is to increase the stiffness of the fuselage, in particular the wing. While such an increase in stiffness may increase the maximum operational speed at which the aircraft can safely operate without reaching the flutter point, a disadvantage is that an increase in stiffness is typically associated with an increase in weight. This has the disadvantage of reducing the maximum payload that the aircraft can carry, which unfortunately reduces the number of people or the weight of the cargo that can be transported. Again, such a reduction in payload is undesirable and may have an adverse effect on the overall commercial viability of the proposed aircraft design. A box wing aircraft or a closed wing aircraft is a specific type of aircraft in which there are typically two wings on each side of the aircraft, which are connected to each other by struts/brackets or winglets at or near each wing tip, such that on each side of the aircraft, the front and rear wings (or alternatively, the upper and lower wings) are secured to each other (in addition to the connection to the fuselage) using mechanical connections. The box wing structure may provide additional wing stiffness, which is beneficial for flutter. However, there are certain problems and challenges associated with box wing aircraft. If a box wing aircraft has rotors mounted to each wing, there is a problem in that the airflow through the rotors mounted to the front wings may adversely affect the rotors mounted to the rear wings because the wake of the front rotors effectively passes through the rear rotors. In this way, any vertical overlap between the swept areas of the rotors of the front and rear wings may generate noise and be aerodynamically inefficient. In some box wing aircraft, the rear wing is mounted directly to the fuselage of the aircraft. This arrangement increases the stiffness of the rear wing, which is beneficial for increasing the flutter point. However, such mounting arrangements typically reduce the vertical gap between the front and rear wings, potentially resulting in the aforementioned undesirable overlap between the rotor of the front wing and the swept area of the rotor of the rear wing. Furthermore, the mounting arrangement of the rear wing to th