Vertical take-off aircraft, procedures for operating a vertical take-off aircraft

Abstract

A vertical take-off aircraft (1) with a wing (2) is proposed, wherein the wing (2) has a propeller (3) arranged in a propeller channel (3.1) for generating an airflow (4) along an upward direction (Z) of the vertical take-off aircraft (1), wherein the wing (2) has a multi-part flap (5) which, in a closed position, is provided for closing the propeller channel (3.1), and wherein, in an open position, the flap (5) is provided as an air guide element for directing the airflow (4) into the propeller channel (3.1). Furthermore, a method is proposed.

Description

[0001] The present invention relates to a vertical takeoff aircraft having a propeller arranged in a propeller duct in a wing. Furthermore, the present invention relates to a method for operating a vertical takeoff aircraft.

[0002] Vertical takeoff aircraft are well known in the art. To generate lift, the propulsion units of some vertical takeoff aircraft can be rotated, so that they generate either thrust or lift depending on their rotational position. The design of such a rotating engine is complex, and the rotating engines themselves are sometimes prone to failure.

[0003] An alternative to this is the provision of lift-generating engines in addition to those designed solely for propulsion. Such additional engines are, for example, housed in the wings of the vertical takeoff aircraft, allowing them to provide a uniform lift to the vertical takeoff aircraft.

[0004] The disadvantage of this is that during the forward motion of the vertical takeoff aircraft, the aerodynamics of the wing are disrupted, and less lift is generated by the wing than would be possible without this disruption. Furthermore, the arrangement of the engines for lift within the wing means that there is little space along the upward direction of the vertical takeoff aircraft for efficient airflow to the engine. Typically, such engines have propellers located in a propeller duct in the wing. The airflow to the propeller is hardly directed, but is generated diffusely from above the wing.

[0005] Vertical takeoff aircraft whose wings have a propeller duct are known from the publications US 3 088 694 A, CN 1 14 620 226 B, KR 10 2019 0 047 446 A, CN 2 08 198 824 U, WO 2019 / 062 257 A1, US 2017 / 0 158 322 A1, and US 3 171 613 A. The propeller duct can be closed with a multi-part flap. When open, the flap components effectively form air deflectors.

[0006] An object of the present invention is therefore to provide a vertical take-off aircraft and a method for operating a vertical take-off aircraft in which the described disadvantages of the prior art do not occur, but which enable aerodynamically efficient wings and a cleverly directed air flow to a propeller in the wing.

[0007] This problem is solved by claims 1 and 8.

[0008] The vertical takeoff aircraft according to the invention has a wing containing a propeller duct. A propeller is arranged in the propeller duct, which generates lift during operation. Thus, for example, vertical takeoff, vertical landing, or hovering can be enabled by the operation of the propeller.

[0009] In addition, a flap is mounted on the wing that covers the propeller duct when closed. This advantageously ensures that the aerodynamically effective surface of the wing is barely affected by the propeller duct.

[0010] The flap is made up of several parts and can be moved from a closed position to an open position. In the open position, the flap no longer covers the propeller duct, but instead serves as an air guide element that effectively directs the airflow into the propeller duct during propeller operation.

[0011] It's conceivable that the flap will automatically move from the closed to the open position when the propeller is started up. It's also conceivable that the flap will automatically move from the open to the closed position when the propeller is shut down.

[0012] Advantageous embodiments and further features of the invention can be found in the dependent claims and the description based on the drawings.

[0013] According to a preferred embodiment of the present invention, the flap is round in the closed position. This covers the entire surface of the generally round propeller duct. However, it is also conceivable for the flap to have a triangular, square, preferably square, or polygonal shape.

[0014] According to the invention, the flap is two-part and has a first partial flap and a second partial flap. When the flap is moved from the closed position to the open position, the first and second partial flaps are displaced laterally along the transverse direction of the vertical takeoff aircraft and upwardly along the upward direction of the vertical takeoff aircraft. In this way, the flap covering the recess is advantageously brought into a position ideally suited for directing the airflow toward the propeller duct.

[0015] In particular, the first and second flaps are each connected to the wing via an inner and an outer link rod. The inner link rod is the rod located closer to the propeller. The outer link rod, on the other hand, is positioned farther away from the propeller. The simple connection of the flaps to the wing creates a very stable and low-maintenance mechanism.

[0016] According to a further preferred embodiment of the present invention, it is provided that the inner joint rods and / or the outer joint rods are rigid, and that the inner joint rods and / or the outer joint rods are each pivotally connected to the wing and pivotally connected to one of the partial flaps. The axes of rotation of the pivot joints are preferably arranged along the longitudinal direction of the vertical take-off aircraft. This contributes to a robust construction of the vertical take-off aircraft and thus to an improvement in safety. The joint rods are preferably arranged in recesses in the wing so that they can be stowed in an aerodynamically advantageous manner.

[0017] According to the invention, when the flap is open, airflow is allowed above and below the partial flaps into the propeller duct. This represents an advantageous way to direct the air into the propeller duct in a controlled manner. By directing the airflow through the partial flaps, the air intake by the propeller from above the wing contributes significantly more to lift.

[0018] According to a further preferred embodiment of the present invention, it is provided that, in the open position of the flap, the outer ends of the partial flaps are arranged further away from the wing in the upward direction of the vertical take-off aircraft than the inner ends of the partial flaps. This results in a funnel-shaped contour of the open flap that is open at the top, which contributes to highly efficient airflow intake into the propeller. The outer ends in the sense of the present invention are the ends of the partial flaps that are further away from the propeller than the inner ends when the flap is open in the transverse direction of the vertical take-off aircraft. In particular, it is provided that the inner ends of the partial flaps are arranged directly opposite one another when the flap is closed.

[0019] Preferably, the flap has an upwardly convex contour along a plane spanned by the vertical and transverse directions of the vertically takeoff aircraft. This only slightly impairs the aerodynamically effective area of ​​the wing. At the same time, sufficient space is created in the propeller tunnel to accommodate a powerful propeller in the wing to generate strong lift.

[0020] According to a further preferred embodiment of the present invention, the propeller is electrically operated, preferably battery-powered. This enables quiet and environmentally friendly operation of the vertical takeoff aircraft.

[0021] A further object of the present invention to solve the problem formulated at the outset is a method according to the invention for operating a vertical take-off aircraft, in which, in order to operate the propeller, the flap is moved from the closed position to the open position, so that the open flap directs the air flow into the propeller duct.

[0022] All details, features and advantages disclosed above in the context of the vertical take-off aircraft according to the invention relate equally to the method according to the invention.

[0023] Further details, features, and advantages of the invention will become apparent from the drawings and the following description of preferred embodiments with reference to the drawings. The drawings represent only exemplary embodiments of the invention, which do not limit the scope of the invention. Fig. 1 (a)-(b) schematically illustrate a section through a wing of a vertical take-off aircraft according to an exemplary embodiment of the present invention, viewed in the longitudinal direction of the vertical take-off aircraft. Fig. 1 (c) illustrates a schematic plan view of a wing of a vertical takeoff aircraft according to an exemplary embodiment of the present invention. Fig. 2 (a)-(b) schematically illustrate a section through a wing of a vertical take-off aircraft according to another exemplary embodiment of the present invention, viewed in the longitudinal direction of the vertical take-off aircraft. Fig. 2 (c) is a schematic plan view of a wing of a vertical take-off aircraft according to the Fig. 2 (a)-(b) illustrates an exemplary embodiment of the present invention. Fig. 3 (a)-(b) schematically illustrate a section through a wing of a vertical take-off aircraft according to another exemplary embodiment of the present invention, viewed in the longitudinal direction of the vertical take-off aircraft. Fig. 3 (c) is a schematic plan view of a wing of a vertical take-off aircraft according to the Fig. 3 (a)-(b) illustrates an exemplary embodiment of the present invention. Fig. 1 to 3 illustrate schematic views of vertical takeoff aircraft according to exemplary embodiments in accordance with various embodiments of the present invention.

[0024] Fig. 1 (a), (b), Fig. 2 (a), (b) and Fig. 3 (a), (b) schematically illustrate sections through a wing 2 of a vertical take-off aircraft 1 according to exemplary embodiments of the present invention, viewed in the longitudinal direction X of the vertical take-off aircraft 1.

[0025] To generate lift, the vertical takeoff aircraft 1 has a propeller 3, which is arranged within the wing 2 in a propeller duct 3.1. In the exemplary embodiment shown, the propeller 3 is battery-powered.

[0026] During flight in the longitudinal direction X, the vertically takeoff aircraft 1 is powered by engines (not shown here) to generate propulsion. The lift required for flight is then provided by aerodynamically effective surfaces, such as the surfaces of the wings 2. The propeller 3 shown is not required for this purpose and is therefore out of service.

[0027] To ensure that the aerodynamic effect of the wings 2 is not impaired or is impaired as little as possible during flight along the longitudinal direction X, a round, multi-part flap 5 is provided on the wing 2. When the propeller 3 is not in operation, the flap 5 closes the propeller channel 3.1 and ensures that the propeller channel 3.1 hardly impairs the aerodynamic effect of the wing 2.

[0028] To provide sufficient space for the propeller 3, the flap 5 is upwardly convex, relative to the section shown here, in the plane spanned by the upward direction Z and the transverse direction Y of the vertical takeoff aircraft 1. This allows for generous space in the propeller duct 3.1 while minimizing the impact on the aerodynamic performance of the wing 2.

[0029] For a vertical take-off, a vertical landing or a hover with no or only slight movement along the longitudinal direction X of the vertical take-off aircraft 1, the propeller channel 3.1 is opened by moving the flap 5 from the closed position as shown in the Fig. 1 (a), Fig. 2 (a) and Fig. 3 (a), into the open position as shown in the Fig. 1 (b) and (c), 2 (b) and (c) and 3 (a) and (c).

[0030] For this purpose, a first partial flap 5.1 and a second partial flap 5.2 are pivoted such that they expose the propeller duct 3.1 and serve as air guiding elements for directing an air flow 4 into the propeller duct 3.1. The upward and outward movement of the partial flaps 5.1, 5.2 is indicated by arrows in the figures.

[0031] The convex shape of the flap 5 described above also has an advantageous effect on the guidance of the air flow 4 into the propeller duct 3.1. For this purpose, the partial flaps 5.1, 5.2 are moved such that the inner ends 9 of the partial flaps 5.1, 5.2 are arranged lower in the vertical direction Z than the outer ends 8. The air flow 4 is guided above and below the partial flaps 5.1, 5.2 into the propeller duct 3.1, as shown in the Fig. 1 (b), Fig. 2 (b) and Fig. 3 (b).

[0032] The way in which the partial flaps 5.1, 5.2 are hinged to the wing 2 ensures good mechanical stability and a high degree of operational reliability. The partial flaps 5.1, 5.2 are each hinged to the wing 2 via an inner hinge rod 6 and an outer hinge rod 7. The hinge points between the partial flaps 5.1, 5.2 and the hinge rods 6, 7 can each be rotated.

[0033] The Fig. 1 (a), (b) and (c) illustrate an exemplary embodiment in which the joint rods 6, 7 are hinged to the wing 2 outside the propeller duct 3.1. The inner joint rods 6 are attached to the inner ends 9 of the partial flaps 5.1, 5.2, and the outer joint rods 7 are attached to the outer ends 8 of the partial flaps 5.1, 5.2. This allows all joint rods 6, 7 to be arranged outside the propeller duct 3.1. The air flow 4 is therefore not disrupted by the joint rods 6, 7. However, the required greater length of the joint rods 5, 6 means greater play in the mechanism and a larger space requirement around the propeller duct 3.1 for unfolding the flap 5.

[0034] The Fig. 2 (a), (b) and (c) illustrate an exemplary embodiment in which the articulated rods 6, 7 are articulated at the inner ends 9 of the partial flaps 5.1, 5.2. In this arrangement, the articulated rods 6, 7 are pivoted at least partially into the region of the propeller channel 3.1 in order to close the flaps 5. Since the articulated rods 6, 7 can be made shorter, the connection of the partial flaps 5.1, 5.2 to the wing 2 is more stable. Furthermore, the partial flaps 5.1, 5.2 are arranged in a more space-saving manner during use, so that less space needs to be provided around the propeller channel 3.1 and several propeller channels 3.1 can be arranged closer together on the wing 2.

[0035] The Fig.3 (a), (b), and (c) depict an exemplary embodiment of the vertical takeoff aircraft 1, in which the outer link rods 7 are telescopically designed and are hinged to the outer ends of the partial flaps 5.1, 5.2. The inner link rods 6 are hinged to the inner ends of the flaps 5.1, 5.2. This results in a very space-saving arrangement that allows for steeply arranged partial flaps 5.1, 5.2 and a very dense arrangement of several propeller rods 3.1 next to one another on a wing 2.

Claims

[1] Vertical take-off aircraft (1), comprising a wing (2), wherein the wing (2) has a propeller (3) arranged in a propeller duct (3.1) for generating an air flow (4) along an upward direction (Z) of the vertical take-off aircraft (1), wherein the wing (2) has a multi-part flap (5) which, in a closed position, is provided for closing the propeller duct (3.1), wherein the flap (5) is provided, in an open position, as an air guide element for directing the air flow (4) into the propeller duct (3.1), wherein the flap (5) is two-part and has a first partial flap (5.1) and a second partial flap (5.2), wherein when the flap (5) is transferred from the closed position to the open position, the first and second partial flaps (5.1, 5.2)2) be displaced laterally along the transverse direction (Y) of the vertical take-off aircraft (1) and upwards along the upward direction (Z) of the vertical take-off aircraft (1), . characterized by that in the open position of the flap (5) the air flow (4) above the partial flaps (5.1, 5.2) and below the partial flaps (5.1, 5.2) is enabled into the propeller duct (3.1). [2] Vertical take-off aircraft (1) according to claim 1, characterized by that the flap (5) is round in the closed position. [3] Vertical take-off aircraft (1) according to one of the preceding claims, characterized by that the first partial flap (5.1) and the second partial flap (5.2) are each articulated to the wing (2) via an inner joint rod (6) and an outer joint rod (7). [4] Vertical take-off aircraft (1) according to claim 3, characterized bythat the inner joint rods (6) and the outer joint rods (7) are rigid and that the inner joint rods (6) and / or the outer joint rods (7) are each rotatably articulated on the wing (2) and rotatably on one of the partial flaps (5.1, 5.2), wherein the axes of rotation of the rotary joints are preferably each arranged along the longitudinal direction (X) of the vertically take-off aircraft (1). [5] Vertical take-off aircraft (1) according to one of the preceding claims, characterized by that in the open position of the flap (5), outer ends (8) of the partial flaps (5.1, 5.2) are arranged further away from the wing (2) along the upward direction (Z) of the vertically take-off aircraft (1) than inner ends (9) of the partial flaps (5.1, 5.2). [6] Vertical take-off aircraft (1) according to one of the preceding claims, characterized bythat the flap (5) has an upwardly convex contour along a plane spanned by the vertical direction (Z) and the transverse direction (Y) of the vertically take-off aircraft (1). [7] Vertical take-off aircraft (1) according to one of the preceding claims, characterized by that the propeller (3) is electrically and preferably battery-powered. [8] Method for operating a vertical take-off aircraft (1) according to one of the preceding claims, characterized by that to operate the propeller (3) the flap (5) is moved from the closed position to the open position so that the open flap directs the air flow (4) into the propeller duct (3.1)

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