WO2025236002A1 - Vtol aircraft with independently tilting channel wing propulsors - Google Patents

Abstract

A method of vector propulsion in a canard/wing layout of a VTOL aircraft is disclosed. Channel wings with embedded propellers as a system can vary tilt angle depending desired flight mode. Variations in angle of tilt of the channel wing propulsors are independent to the angle of incidence of a separate lifting surfaces. Variation in angle of tilt of the channel wing propulsors are also independent to one or more channel wing propulsors. Channel wing propulsors may be used to achieve VTOL flight by tilting channel wing propulsors such that the resultant vector of the created by the propeller thrust and lift vector of the channel wing is in the vertical direction.

Description

VTOL Aircraft with Independently Tilting Channel Wing Propulsors

RELATED APPLICATIONS

This application claims the benefit of U.S. provisional application no. 63/645,268 filed May 10, 2024, the contents of which are hereby incorporated by reference in their entirety.

TECHNICAL FIELD

The present invention relates to aircraft design. In particular, embodiments of the present invention are directed to fixed wing vertical takeoff and landing (VTOL) aircraft that allow the tilt angle of a channel wing with an embedded propeller as a propulsive system to be varied independently of the incidence angle of the aircraft’s fixed aerodynamic surfaces, and the tilt angle of other channel wing propulsors.

BACKGROUND OF THE INVENTION

A channel wing propulsor is a system defined as an airfoil in the shape of a semicircular duct that is sized to accommodate an embedded propeller. A purpose of a channel wing propulsor is to augment the thrust created by a propeller by generating additional lift due to induced airflow through the semi-circular airfoil. As a result, the channel wing propulsor concept sees particular benefit by augmenting propulsive thrust in situations with zero or low forward airspeed.

To enable VTOL capability, an aircraft leveraging channel wing propulsive technology may control the propulsors to provide a vertical thrust vector. This can be achieved by varying the tilt angle of the channel wing propulsor, defined as the relative angle of the channel wing chord with respect to a longitudinal reference axis along the length of the fuselage.

To provide predictable low speed flight characteristics, the tilt angle of the channel wing propulsor may be varied independently from the rest of the lifting surface and other propulsors. This may ensure that the angle of attack of the wing (defined as the angle between the wing chord and relative wind) is constant throughout the transition from VTOL to wing-borne flight.

This invention is related to US 10,696,390 B2, by one of the present inventors, issued June 30, 2020, the contents of which are hereby incorporated. SUMMARY OF INVENTION

One embodiment pertains to an aircraft of a wing/canard configuration that is capable of both VTOL and wing-borne flight. To achieve propulsion and control, the aircraft uses propellers embedded in a channel wing, and allows the propeller and channel wing to tilt independently of other lifting surfaces and propulsors

To achieve hover flight, the propellers and channel wings are tilted to an angle such that the resultant lift and thrust vector is in the vertical direction. Forward and aft (longitudinal) maneuvering in hover flight is achieved through a combination of pitch attitude change and varying tilt angle of the propellers and channel wings. Lateral movement is achieved by varying roll attitude. Yaw is controlled through differential tilt of laterally arranged channel wing propulsors.

Transition to wing-borne flight is achieved by tilting all channel wing propulsors forward. As the aircraft gains airspeed, flight control laws blend. Upon reaching the forward position, the aircraft maneuvers via aerodynamic control surfaces. Transition back to hover is achieved by tilting the channel wing propulsors back and allowing the aircraft to decelerate back into a hover.

In some aspects, the techniques described herein relate to a Vertical Take-Off and Landing (VTOL) aircraft in a wing/canard configuration capable of VTOL, semi- wing-borne, and wing-borne flight, said aircraft including: a fuselage defining fore and aft sections, a left side, a right side, a topside, a bottom side, and a longitudinal centerline; a canard aerodynamic lifting surface extending from the fuselage fore section left side, defining a left canard rotational axis, and extending from the fuselage fore section right side, defining a right canard rotational axis; a wing aerodynamic lifting surface extending from the fuselage aft section left side, defining a left wing rotational axis, and extending from the fuselage aft section right side, defining a right wing rotational axis; left and right fore channel wing propulsors disposed respectively to the left and right sides of the fuselage in the canard aerodynamic lifting surface; and left and right aft channel wing propulsors disposed respectively to the left and right sides of the fuselage in the wing aerodynamic lifting surface; wherein said left fore, right fore, left aft, and right aft channel wing propulsors each include a semi-circular airfoil duct and each is rotatable about, respectively, the left canard, right canard, left wing, and right wing rotation axes; wherein the aircraft is configurable in a VTOL flight mode in which the channel wing propulsors are rotated such that resultant propulsive vectors are substantially vertical; wherein the aircraft is configurable in a semi-wing-borne flight mode in which the channel wing propulsors are rotated such that resultant propulsive vectors generate forward airspeed insufficient for wing-borne flight; wherein the aircraft is configurable in a wing-borne flight mode in which the channel wing propulsors are rotated such that resultant propulsive vectors generate forward airspeed sufficient for wing-borne flight; and wherein the aircraft's aerodynamic lifting surfaces other than the channel wing propulsors are at a fixed angle of incidence throughout all modes of flight.

In some aspects, the techniques described herein relate to an aircraft, wherein a rotation of at least one of the channel wing propulsors is independent of one or more of the remaining channel wing propulsors. In some aspects, the techniques described herein relate to an aircraft, wherein the channel wing propulsors in VTOL flight mode are configurable to provide differential tilting of laterally aligned channel wing propulsors to achieve vectored yaw control of the aircraft. In some aspects, the techniques described herein relate to an aircraft, wherein the channel wing propulsors in VTOL flight mode are configurable to provide independent tilting of laterally aligned channel wing propulsors to effect forward or aft longitudinal translation of the aircraft.

In some aspects, the techniques described herein relate to an aircraft, further including aerodynamic control surfaces other than the channel wing propulsors to aid in control of the aircraft throughout all stages of flight. In some aspects, the techniques described herein relate to an aircraft, wherein the channel wing propulsors in wing- borne flight mode are configurable to provide thrust differentially to control yaw. In some aspects, the techniques described herein relate to an aircraft further including aerodynamic rudders or drag producing devices to effect achieve yaw control in wing- borne or semi-wing-borne flight mode. In some aspects, the techniques described herein relate to an aircraft, wherein the channel wing propulsors are independently controllable in wing-borne or semi-wing-borne flight mode to effect air braking or augment control surfaces.

In some aspects, the techniques described herein relate to an aircraft, wherein the channel wing propulsors, configured in wing-borne flight mode are controllable in combination with elevators, ailerons, and differential thrust to create stable flight. In some aspects, the techniques described herein relate to an aircraft, wherein the channel wing propulsors, configured in wing-borne or semi-wing-borne flight mode are controllable to effect flight without use of aerodynamic control surfaces. In some aspects, the techniques described herein relate to an aircraft wherein a drive power source for said channel wing propulsors is electrically powered. In some aspects, the techniques described herein relate to an aircraft wherein a drive power source for said channel wing propulsors uses internal combustion. In some aspects, the techniques described herein relate to an aircraft wherein a drive power source for said channel wing propulsors uses a hybrid power system. In some aspects, the techniques described herein relate to an aircraft,, wherein the channel wing propulsors, configured in wing-borne or semi-wing-borne flight mode are controllable to effect short or conventional takeoff and landing. In some aspects, the techniques described herein relate to an aircraft wherein each of the channel wing propulsors is configured for direct drive or mechanically coupled from a respective drive power source.

In some aspects, the techniques described herein relate to a vectored propulsion system in an aircraft including: a tiltable channel wing propulsor having a center of rotation substantially transverse to a thrust vector of the channel wing propulsor, said channel wing propulsor including a semi-circular airfoil, an embedded propeller, a drive system, and a mounting structure; and a mechanical system controllable to effect a tilt of the channel wing propulsor about the center of rotation; wherein the tilt of the channel wing propulsor is controlled independently of other controls of the aircraft via a tilt control actuator; and wherein the tilt of the channel wing propulsor is articulated about a fixed structural member fixed in the aircraft's body frame.

In some aspects, the techniques described herein relate to a vectored propulsion system, wherein the tilt of the channel wing propulsor may be at any rotation about the center of rotation. In some aspects, the techniques described herein relate to a vectored propulsion system wherein the mechanical system includes a linear actuator inside a fuselage of the aircraft. In some aspects, the techniques described herein relate to a vectored propulsion system wherein the mechanical system includes a gear mechanism. In some aspects, the techniques described herein relate to a vectored propulsion system wherein the linear actuator is coupled to a respective drive power source of the channel wing propulsor. In some aspects, the techniques described herein relate to a vectored propulsion system wherein a drive for the mechanical system is electrically powered. In some aspects, the techniques described herein relate to a vectored propulsion system wherein a drive for the mechanical system is pneumatic. In some aspects, the techniques described herein relate to a vectored propulsion system wherein a drive for the mechanical system is hydraulic. In some aspects, the techniques described herein relate to a vectored propulsion system, wherein the embedded propeller is disposed in the channel wing propulsor to provide one of push thrust or pull thrust.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an isometric view of an exemplary embodiment of the aircraft in a VTOL configuration showing the layout of channel wing propulsors providing thrust- borne flight.

FIG. 2 illustrates an isometric view of an exemplary embodiment of the aircraft in a VTOL configuration showing the layout of channel wing propulsors at different tilt angles in thrust-borne flight.

FIG. 3 illustrates an isometric view of an exemplary embodiment of the aircraft in wing-borne flight.

FIG. 4 illustrates a detailed semitransparent isometric view of an exemplary channel wing propulsor with tilt actuator mechanism via a linear actuator in a preferred embodiment.

FIG. 5 illustrates a detailed semitransparent isometric view of an exemplary channel wing propulsor with a tilt actuator mechanism via a geared system in an exemplary embodiment.

DETAILED DESCRIPTION

As used herein any reference to an “embodiment” or “some embodiments” means that a particular element, feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the inventive concepts disclosed herein. The appearances of the phrase “in some embodiments” in various places in the specification are not necessarily all referring to the same embodiment, and embodiments of the inventive concepts disclosed may include one or more of the features expressly described or inherently present herein, or any combination of sub-combination of two or more such features, along with any other features which may not necessarily be expressly described or inherently present in the instant disclosure.

FIG. 1 provides a view of an aircraft 90 in accordance with an embodiment of the invention in a VTOL configuration, relying primarily on thrust forces to stay aloft and maneuver. Here, the rear channel wing propulsors 102 and 101 and forward channel wing propulsors 103 and 104 are set to an angle such that the resultant vector created by the propeller thrust and lift vector is in the vertical direction. During the VTOL configuration, the lifting surfaces 100 and 105 are at set to a fixed angle of incidence relative to the longitudinal axis of the fuselage. The lifting surfaces 100 and 105 are set at the optimal angle of incidence for wing-borne flight. This provides an added benefit of ensuring predictable low speed flight characteristics in semi wing-borne and wing-borne flight and improved attitude control against wind.

FIG. 2 is a secondary view of the aircraft 90 in a VTOL configuration. In this secondary view each channel wing propulsor 101, 102, 103, and 104 can vary tilt angle independently from one another. Laterally arranged channel wing propulsors can actuate independently, achieving differential tilt of 101 and 102 in addition with 103 and 104 enabling vectored yaw in a hover. Simultaneously, tilting of the channel wing propulsors concurrently at the wing 101 and 102 and at the canard 103 and 104 creates forward and aft (longitudinal) movement in hover flight. The ability to independently vary tilt angle of each channel wing propulsor creates fine vectored thrust movements enabling corrections against disturbances. This ensures stability of the aircraft in a hover, stable transition into semi-wing-borne flight, and proceeding wing-borne flight.

FIG. 3 is a view of the aircraft 90 in a wing-borne flight configuration. Upon transition from semi-wing-borne flight, channel wing propulsors 101 and 102 are set so that the resultant thrust vector is in the forward direction. During this configuration, the outer lifting surfaces 100 and 105 generate majority of the lift with aid of resultant lift from the channel wing propulsors 101 , 102, 103, 104, to stay aloft. The aircraft maneuvers in wing-borne flight with aerodynamics controls surfaces via ailerons 300 and elevators 301. Yaw control in wing-borne flight is achieved by differential thrust of laterally positioned channel wing propulsors 101 and 102 in addition to 103 and 104. This aircraft is in a wing/canard configuration and is appropriately sized for desirable flying characteristics in wing-borne flight. As a result, the canard channel wing propulsors 103 and 104 are proportionately scaled about the center of gravity and aerodynamic center to the wing channel wing propulsors 101 and 102. This proportionality complements stability through transition from semi-wing-borne flight into wing-borne flight.

For this wing-borne configuration to revert into a VTOL configuration the individual channel wing propulsors 101 , 102, 103, 104, begin increasing their tilt angle relative to the angle of incidence of the wings chord line. During the process of tilting the channel wing propulsors back to the desired resultant vertical thrust angle, channel wing propulsors, due to their inherent geometry, act as air brakes to achieve desired deceleration profile. Transition from semi-wing-borne lift back into VTOL mode is also a gentle operation due to the proportionality between the canard and wing channel wing propulsors.

FIG. 4 is a semitransparent isometric detail view of a channel wing propulsor, adjacent lifting surface 105, and an associated preferred mechanism to enable individual tilting of a channel wing propulsor. The channel wing propulsor comprises of an airfoil in the shape of a semi-circular duct 400 with an embedded propeller 401. Attached to the propeller is a direct drive motor 402 which is mounted to a center structure 403. The duct, propeller, motor, and center mount structure can tilt together about a fixed circular spar 404. The fixed spar 404 which is used as structure to mount the lifting surface 105, is mounted to a fuselage structure 405 (semitransparent for illustration purposes). Inside the fuselage structure is the location of a tilting mechanism. Rotation of the tilting mechanism is achieved using a linear actuator 406 and linkage assembly 407. The linkage assembly 407 transfers linear motion into rotational motion. The rotational motion is transferred axially about the fixed spar to connect to the channel wing propulsor. This mechanism is used for all channel wing propulsors regardless of location adjacent to the wing or canard.

FIG. 5 is a semitransparent isometric detail view of a channel wing propulsor, adjacent lifting surface 105, and an additional mechanism to enable individual tilting of a channel wing propulsor. As presented in figure 4, the channel wing propulsor 103, rotates about a fixed circular spar 404. The fixed spar 404 which is used as structure to mount the lifting surface 105, is mounted to a fuselage structure 405. A servo motor with a drive gear 501 is mounted to a channel wing propulsor 103. A driven gear is mounted to the fuselage structure 502. Rotation of the driver gear in gear mesh generates the desired tilt angle of the channel wing propulsor.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, by way of illustration and example only, it is clearly understood that the present invention is not to be construed as limiting the present invention, and various changes and modifications may be made by those skilled in the art within the protective scope of the invention without departing off the spirit of the present invention.

Claims

WHAT IS CLAIMED IS:

1. A Vertical Take-Off and Landing (VTOL) aircraft in a wing/canard configuration capable of VTOL, semi-wing-bome, and wing-borne flight, said aircraft comprising: a fuselage defining fore and aft sections, a left side, a right side, a topside, a bottom side, and a longitudinal centerline; a canard aerodynamic lifting surface extending from the fuselage fore section left side, defining a left canard rotational axis, and extending from the fuselage fore section right side, defining a right canard rotational axis; a wing aerodynamic lifting surface extending from the fuselage aft section left side, defining a left wing rotational axis, and extending from the fuselage aft section right side, defining a right wing rotational axis; left and right fore channel wing propulsors disposed respectively to the left and right sides of the fuselage in the canard aerodynamic lifting surface; and left and right aft channel wing propulsors disposed respectively to the left and right sides of the fuselage in the wing aerodynamic lifting surface; wherein said left fore, right fore, left aft, and right aft channel wing propulsors each comprise a semi-circular airfoil duct and each is rotatable about, respectively, the left canard, right canard, left wing, and right wing rotation axes; wherein the aircraft is configurable in a VTOL flight mode in which the channel wing propulsors are rotated such that resultant propulsive vectors are substantially vertical; wherein the aircraft is configurable in a semi-wing-bome flight mode in which the channel wing propulsors are rotated such that resultant propulsive vectors generate forward airspeed insufficient for wing-borne flight; wherein the aircraft is configurable in a wing-bome flight mode in which the channel wing propulsors are rotated such that resultant propulsive vectors generate forward airspeed sufficient for wing-borne flight; and wherein the aircraft’s aerodynamic lifting surfaces other than the channel wing propulsors are at a fixed angle of incidence throughout all modes of flight.

2. The aircraft according to claim 1, wherein a rotation of at least one of the channel wing propulsors is independent of one or more of the remaining channel wing propulsors.

3. The aircraft according to claim 1, wherein the channel wing propulsors in VTOL flight mode are configurable to provide differential tilting of laterally aligned channel wing propulsors to achieve vectored yaw control of the aircraft.

4. The aircraft according to claim 1, wherein the channel wing propulsors in VTOL flight mode are configurable to provide independent tilting of laterally aligned channel wing propulsors to effect forward or aft longitudinal translation of the aircraft.

5. The aircraft according to claim 1, further comprising aerodynamic control surfaces other than the channel wing propulsors to aid in control of the aircraft throughout all stages of flight.

6. The aircraft according to claim 1, wherein the channel wing propulsors in wing-borne flight mode are configurable to provide thrust differentially to control yaw.

7. The aircraft according to claim 1 further comprising aerodynamic rudders or drag producing devices to effect achieve yaw control in wing-borne or semi-wing-borne flight mode.

8. The aircraft according to claim 1, wherein the channel wing propulsors are independently controllable in wing-borne or semi-wing-borne flight mode to effect air braking or augment control surfaces.

9. The aircraft according to claim 1, wherein the channel wing propulsors, configured in wing-borne flight mode are controllable in combination with elevators, ailerons, and differential thrust to create stable flight.

10. The aircraft according to claim 1, wherein the channel wing propulsors, configured in wing-borne or semi-wing-borne flight mode are controllable to effect flight without use of aerodynamic control surfaces.

11. The aircraft of claim 10 wherein a drive power source for said channel wing propulsors is electrically powered.

12. The aircraft of claim 10 wherein a drive power source for said channel wing propulsors uses internal combustion.

13. The aircraft of claim 10 wherein a drive power source for said channel wing propulsors uses a hybrid power system

14. The aircraft, according to claim 1, wherein the channel wing propulsors, configured in wing-borne or semi-wing-bome flight mode are controllable to effect short or conventional takeoff and landing.

15. The aircraft of claim 1 wherein each of the channel wing propulsors is configured for direct drive or mechanically coupled from a respective drive power source.

16. A vectored propulsion system in an aircraft comprising: a tiltable channel wing propulsor having a center of rotation substantially transverse to a thrust vector of the channel wing propulsor, said channel wing propulsor comprising a semicircular airfoil, an embedded propeller, a drive system, and a mounting structure; and a mechanical system controllable to effect a tilt of the channel wing propulsor about the center of rotation; wherein the tilt of the channel wing propulsor is controlled independently of other controls of the aircraft via a tilt control actuator; and wherein the tilt of the channel wing propulsor is articulated about a fixed structural member fixed in the aircraft’s body frame.

17. The vectored propulsion system according to claim 16, wherein the tilt of the channel wing propulsor may be at any rotation about the center of rotation.

18. The vectored propulsion system according to claim 16 wherein the mechanical system comprises a linear actuator inside a fuselage of the aircraft.

19. The vectored propulsion system according to claim 16 wherein the mechanical system comprises a gear mechanism.

20. The vectored propulsion system according to claim 18 wherein the linear actuator is coupled to a respective drive power source of the channel wing propulsor.

21. The vectored propulsion system of claim 20 wherein a drive for the mechanical system is electrically powered.

22. The vectored propulsion system of claim 20 wherein a drive for the mechanical system is pneumatic.

23. The vectored propulsion system of claim 20 wherein a drive for the mechanical system is hydraulic.

24. The vectored propulsion system according to claim 16, wherein the embedded propeller is disposed in the channel wing propulsor to provide one of push thrust or pull thrust.