Wing with Duct Having Flap

Abstract

The ducted wing is configured to be connected to an aircraft. The ducted wing includes jet foils arranged in an integrally continuous array. Each jet foil includes a propulsion fan, an upper wing portion, and a lower wing portion extending beyond an end of the upper wing portion. Each jet foil includes a duct formed between the upper wing portion and the lower wing portion, and the propulsion is within the duct. Further, each jet foil may have one or more flaps at a leading edge or a trailing edge of the jet foil. The jet foil may have a flap that controls either an inlet area or an outlet area of the propulsion fan, and a flap that controls so that the aircraft can operate in any of a plurality of different takeoff modes.

Description

Technical Field

[0001] (Cross - Reference to Related Applications) This application claims the benefit of U.S. Provisional Patent Application No. 63 / 356,891, filed on June 29, 2022, which is hereby incorporated by reference in its entirety.

[0002] The present disclosure generally relates to an aircraft including a series of propulsion fans. More specifically, the present disclosure generally relates to a ducted wing having an integrated electric ducted fan that enables variable modes of airflow for conventional takeoff and landing (CTOL), vertical takeoff and landing (VTOL), and short takeoff and landing (STOL) of an aircraft.

Background Art

[0003] (Description of Related Art) Existing electric conventional takeoff and landing jets typically use propulsion fans that utilize open rotors and propellers. These types of propulsion fans have reached their acoustic limits. Conventional propulsion fans have 2 - 5 blades supported at one end, which limits the number of blades to 5 or less. To lower the frequency generated by a conventional propulsion fan to a band that is less perceptible to the human ear, the rotational speed of the fan must be increased. However, since conventional propulsion fans are only supported by a single - end structure, they cannot be driven at higher speeds. Furthermore, since conventional propulsion fans are supported only at one end, the angle of the fan blades may change as the blade fan rotates at high speed, and as a result, the sound heard by the human ear changes. As a result, existing conventional takeoff and landing jets increase noise pollution.

Summary of the Invention

[0004] An aircraft with a wing with a duct incorporating a series of jet foils is disclosed. The aircraft can be configured to carry passengers, cargo, or a combination thereof. Each jet foil includes a thruster and, in some embodiments, a series of flaps for controlling the takeoff and landing mode of the aircraft and the areas of the inlet and outlet of the thruster. The series of jet foils are integrated to form a wing with a duct. A set of flaps can control the takeoff and landing mode according to the set angle of the flaps, enabling CTOL, VTOL, and STOL depending on the angle of the flaps. Another set of flaps controls the areas of the inlet and outlet of the thruster to optimize efficiency at various airspeeds. The thruster is embedded in the leading edge of the wing with a duct, minimizing the intake of boundary layer air. In some embodiments, part of the wing with a duct can be used to carry payloads such as sensors, equipment, batteries, and fuel.

Brief Description of the Drawings

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DETAILED DESCRIPTION OF THE INVENTION

[0006] The figures, and the following description, are provided by way of example only, and describe certain embodiments. Those skilled in the art will readily recognize from the following description that alternative embodiments of the structures and methods described herein can be used without departing from the principles described herein. Here, several embodiments are referred to in detail, and these examples are described in the accompanying drawings. Note that where possible, similar or like reference numerals are used in the drawings to indicate similar or like functions.

[0007] Figures 1A, 1B, 1C, 1D, 1E, 1F, and 1G are different views of an aircraft 100 with a ducted wing according to one embodiment. Depending on the orientation of one or more flaps of the ducted wing, the aircraft 100 can operate in one of a plurality of different landing and takeoff modes, such as conventional takeoff and landing (CTOL), vertical takeoff and landing (VTOL) mode, and short takeoff and landing (STOL) mode, as further described below.

[0008] Specifically, FIG. 1A is a perspective view of the upper front of the aircraft 100 according to one embodiment as seen from the left side, FIG. 1B is a right side view of the aircraft 100 with a ducted wing according to one embodiment, FIG. 1C is a front view of the aircraft 100 with a ducted wing according to one embodiment, FIG. 1D is a left side view of the aircraft 100 with a ducted wing according to one embodiment, FIG. 1E is a rear view of the aircraft 100 with a ducted wing according to one embodiment, FIG. 1F is a bottom view of the aircraft 100 with a ducted wing according to one embodiment, and FIG. 1G is a top view of the aircraft 100 with a ducted wing according to one embodiment. In one embodiment, by using the flaps included in the ducted wing, the aircraft 100 can transition between CTOL, STOL, and VTOL modes according to the required application.

[0009] Generally, the aircraft 100 may be, for example, a regional aircraft capable of carrying passengers and cargo. The aircraft 100 can carry a plurality of passengers, such as from 5 to over 30 passengers, depending on its configuration. In one embodiment, the aircraft 100 is all-electric with a visual flight rules (VFR) range of less than 200 miles, hybrid-electric (using a range extender) to achieve a maximum of 500 miles according to instrument flight rules (IFR), or non-electric for distances over 500 miles.

[0010] The all-electric aircraft 100 can be equipped with a battery that is liquid-cooled, propagation-resistant, quadruple redundant, with a capacity of 384 kWh and an energy density of 255 Whr / kg (back level). The battery pack can include cylindrical battery cells manufactured by Farasis, with an energy density of 305 Whr / kg (cell level), 2C discharge / recharge, and a 2000-cycle life. In a hybrid electric propulsion embodiment, a range extender such as a 250 kW turbogenerator manufactured by Rolls-Royce can be used.

[0011] In one embodiment, the aircraft 100 (e.g., an airplane) includes a fuselage 101, a plurality of ducted wings 103, a continuously arranged jet foil 109, a plurality of booms 105, a plurality of horizontal tails 111 (e.g., wings), a plurality of vertical tails 107 (e.g., wings), and one or more landing mechanisms 113. The horizontal tail 111 and the vertical tail 107 together form the tail of the aircraft 100. It should be noted that in other embodiments, the aircraft 100 may include components different from those shown in FIGS. 1A - 1E.

[0012] The fuselage 101 is the main body of the aircraft 100. The fuselage 101 has a hollow structure. The fuselage 101 may be a single continuous structure or a modular structure formed by a plurality of components together with the fuselage 101. In one embodiment, the fuselage 101 contains one or more payloads. In one embodiment, the aircraft 100 is all-electric. However, the aircraft 100 can utilize a hybrid electric system to enable longer flight times, greater payloads, and / or longer ranges as in the other embodiments described above.

[0013] In one embodiment, the fuselage 101 may further include electrical components for controlling the aircraft 100. Examples of electrical components for controlling the aircraft 100 include one or more controllers such as one or more processors and memory devices used to control the continuously arranged jet foils 109 and actuate one or more control surfaces of the aircraft 100 (e.g., control of ailerons, rudders, elevators, tabs, flaps, spoilers, slats, etc.).

[0014] The jet foils 109 continuously arranged integrally with the ducted wing 103 may include a plurality of thrusters 201 (shown in FIG. 2). In one embodiment, each jet foil includes a part of the ducted wing 103 and a corresponding thruster 201 disposed within the duct of the jet foil 109. Each jet foil 109 is connected to at least one other jet foil 109 and is configured to collectively form the ducted wing 103. An example of the thruster 201 is described in U.S. Provisional Patent Application No. 63 / 356,891, filed on June 29, 2022, which is hereby incorporated by reference in its entirety.

[0015] In one embodiment, the thruster 201 is integrated with the leading edge of the ducted wing 103 rather than the trailing edge of the ducted wing 103. Incorporating the continuously arranged thrusters 201 into the leading edge of the ducted wing 103 rather than the trailing edge of the ducted wing 103 provides many advantages. For example, the thruster 201 has less boundary layer intrusion compared to thrusters located at the trailing edge of the wing, and in the ducted wing 103, the trailing edge of the ducted wing 103 functions as a noise shield, shielding people located on the ground from the jet noise generated by the thruster 201. Therefore, the aircraft 100 reduces noise pollution caused by the ducted wing 103. Furthermore, the ducted wing 103 has a large increase in lift due to the Coanda effect, a smaller total wetted area than a wing with separate podded thrusters, and the inlet of the ducted wing 103 reduces the inflow distortion at high angles of attack.

[0016] The number of the thrusters 201 included in the ducted wing 103 depends on the use of the aircraft 100. For example, 32 thrusters can be used for the ducted wing 103, but any number of thrusters can be used in other embodiments. The plurality of thrusters 201 can generate, for example, a maximum static thrust of 4,465 pounds and a continuous output of 835 kW / 1,128 kW.

[0017] One or more landing mechanisms 113 may be attached to the lower surface of the fuselage 101. The landing mechanism 113 may be, for example, a landing gear (e.g., a tricycle gear) or a landing skid. However, in other embodiments, other landing mechanisms 113 may be used.

[0018] The ducted wing 103 is the main wing near the fuselage of the aircraft 100. The ducted wing 103 is a central element connecting the fuselage 101, the boom 105, the horizontal tail 111, and the vertical tail 107. The ducted wing 103 is located between the first end (e.g., the front) and the second end (e.g., the rear) of the fuselage 101. The ducted wing 103 is configured to provide lift to the aircraft 100 for flight, and in one embodiment, it has anhedral with respect to the fuselage 101 for the purpose of ensuring stability. However, in other embodiments, the ducted wing 103 may have dihedral with respect to the fuselage 101. The ducted wing 103 may be made of composite materials such as carbon fiber, metal (e.g., aluminum or titanium), or alloy.

[0019] In one embodiment, the ducted wing 103 includes a first side 103A disposed on a first side (e.g., the right side) of the fuselage 101 and a second side 103B disposed on a second side (e.g., the left side) of the fuselage 101. The first side 103A of the ducted wing 103 includes a first plurality of integrated thrusters 201A sequentially and integrally arranged over the length of the first side 103A of the ducted wing 103. Similarly, the second side 103B of the ducted wing 103 includes a second plurality of integrated thrusters 201B sequentially and integrally arranged over the length of the second side 103B of the ducted wing 103. The different groups of thrusters 201 integrally arranged on each of the first side 103A and the second side 103B of the ducted wing 103 can be controlled individually. That is, the first plurality of integrated thrusters 201A can be controlled separately from, for example, the second plurality of integrated thrusters 201B.

[0020] In one embodiment, as shown in FIGS. 1A-1G, the first side 103A and the second side 103B of the ducted wing 103 are connected to the lower surface of the fuselage 101. However, in other embodiments, the first side 103A and the second side 103B of the ducted wing 103 may be attached to the upper surface of the fuselage 101 for the purpose of improving ground clearance, passenger access, and cargo loading and unloading. As will be further described below, the ducted wing 103 includes one or more control surfaces, such as flaps and ailerons, for controlling the aircraft 100 during flight and takeoff and landing.

[0021] In one embodiment, the first side 103A and the second side 103B of the ducted wing may be configured as one continuous structure coupled to the lower or upper surface of the fuselage 101. Alternatively, the first side 103A and the second side 103B of the ducted wing 103 may be separate structures attached to the lower or upper surface of the fuselage 101, respectively.

[0022] In one embodiment, the aircraft 100 includes a boom 105 connected to the tip of the ducted wing 103. As shown in the side views of the aircraft in FIGS. 1B and 1D, the body of each boom 105 extends rearward with respect to the front portion of the fuselage 101 such that the end of each boom is positioned in front of the end of the fuselage 101. The tip of the boom 105 can be used for a forward-facing camera or sensor system. There is space for arranging a primary battery system behind this toroidal shape. By arranging the battery behind the toroidal volume, it becomes possible to add a span load in accordance with the structural, aeroelastic, and natural harmony characteristics of the ducted wing 103. The volume of the boom 105 can be used not only for navigation lights but also for additional sensors (such as optical, auditory, visual, olfactory, etc.). The boom 105 also has an air intake for cooling the battery and sensor components.

[0023] In one embodiment, the aircraft 100 includes a horizontal tail 111 attached to the end of the boom 105. As shown in FIGS. 1A to 1D, the horizontal tail 111 is arranged in an outer horizontal tail arrangement. That is, each horizontal tail 111 extends horizontally away from the side of the boom 105 to which the horizontal tail 111 is connected. The horizontal tails arranged outside the horizontal tail 111 can reduce the wetted area, drag, and mass compared to the horizontal stabilizers attached to a conventional fuselage. Also, by arranging the tail 115 outside, it is possible to keep the tail away from the downwash of the continuously arranged propellers 201, which complicates the control at low speeds and during takeoff.

[0024] The horizontal stabilizer 111 attached to the end of the boom 105 has an elevator surface for providing longitudinal stability at all stages of flight. By disposing the horizontal stabilizer 111 outwardly, the horizontal stabilizer 111 is not subject to the downwash of the thruster 201, which complicates control at low speeds and during takeoff and increases the amount of trim change. Therefore, the length of the boom 105 is determined according to an airflow modeling indicating the position of the downwash of the jet foil 109. Further, the length of the boom 105 is also determined according to an airflow modeling such that the horizontal stabilizer 111 is positioned in the upwash region of the vortex shedding separation of the ducted wing 103 around the boom 105. The effect of the horizontal stabilizer 111 is thus increased as the vortex shedding further provides lift. As a result, under cruise conditions, the horizontal stabilizer has a net lift vector oriented in the forward flight direction, whereby a positive thrust component reduces battery consumption. In one embodiment, the horizontal stabilizer 111 has a dihedral angle of approximately 5 degrees to assist with horizontal tip collisions during landing of the aircraft 100. The horizontal stabilizer 111 can have, for example, flaps that can be actuated by an electromechanical actuator.

[0025] The vertical fin 107 (e.g., vertical stabilizer) is disposed on the upper surface of the boom 105 and at the rear end of the boom 105 to reduce the risk of collision between the boom and the fin. In one embodiment, a single vertical fin is attached to the upper surface of the corresponding boom 105 and extends upwardly from the upper surface of the boom 105 towards the sky so that the vertical fin 107 is located above the boom 105. Each vertical fin 107 may have a movable control surface such as a ladder that enables yaw control. The movable control surface of the vertical fin 107 pivots about an end connected to a part of the vertical fin 107 and maintains the aircraft 100 in a straight line with the direction of travel of the aircraft 100. The movable control surface may move (e.g., pivot) to change the direction of travel of the aircraft 100 (e.g., yaw control). The vortex lift-off from the boom 105 also aids the effect of the vertical fin 107. By further aerodynamically optimizing the vortex lift, it is possible to reduce the size of the vertical fin 107 (tail volume coefficient) while maintaining the same or better performance compared to more conventional aircraft designs.

[0026] FIG. 2 is a cross-sectional view of the jet foil 109 continuously arranged integrally with the ducted wing 103 according to one embodiment. By directly incorporating the duct into the airfoil leading edge to form the ducted wing 103, the drag and weight of the duct are minimized, the distortion of the fan inflow is minimized, and low noise is achieved. The ducted wing 103 aligns the airflow and eliminates the need for a high-lift slat. In one embodiment, each jet foil 109 includes a thruster 201 configured to generate thrust, an upper wing portion 230, a lower wing portion 250, and one or more flaps 210.

[0027] In one embodiment, the upper wing portion 230 of the jet foil 109 constitutes the upper half of the duct included in the jet foil 109. The upper wing portion 230 is configured to control the exhaust flow of the thruster 201. The lower wing portion 250 is configured to control different takeoff and landing modes of the aircraft 100. The lower wing portion 250 includes a first lower wing portion 250A at the leading edge of the lower wing portion 250 and extends to a position aligned with the rear end 6 of the upper wing portion 230. In some embodiments, the lower wing portion 250 may include flaps configured to pivot between different angles associated with specific takeoff and landing modes. For example, one angle of the flap is associated with the normal takeoff and landing mode, another angle of the flap is associated with the vertical takeoff and landing mode, and yet another angle is associated with the short takeoff and landing mode.

[0028] The lower wing portion 250A overlaps the upper wing portion 230 and is connected to the upper wing portion 230. The upper wing portion 230 and the first lower wing portion 250A collectively form an integral duct of the jet foil 109. The thruster 201 is disposed between the upper wing portion 230 of the jet foil 109 and the first lower wing portion 250A of the lower wing portion 250.

[0029] The lower wing portion 250 also includes a second lower wing portion 250B. The second lower wing portion 250B extends from the end of the first lower wing portion 250A to the trailing edge of the lower wing portion 250. As shown in FIG. 2, the second lower wing portion 250B does not overlap the upper wing portion 230.

[0030] In one embodiment, one or more flaps 210 are connected to the upper wing portion 230 and the lower wing portion 250. In one embodiment, the flap 210 includes a first flap 210A configured to be attached to the upper wing portion 230 and a second flap 210B configured to be attached to the lower wing portion 250. One end of each flap 210 is configured to be attached to the end of the ducted wing 103. In one embodiment, one end of the flap 210 is configured to be attached to the trailing edge of the ducted wing 103. In another embodiment, one end of the flap 210 is configured to be attached to the leading edge of the ducted wing 103. Each flap 210 is configured to pivot about the attachment point to the edge of the ducted wing 103. The flap 210 can have different configurations depending on the attachment position.

[0031] For example, the second flap 210B may be configured to pivot about the attachment point to the trailing edge of the lower wing portion 250 and may be configured to guide the airflow from the thruster 201 to control lift and drag. The second flap 210B enables a plurality of takeoff modes including VTOL, STOL, and CTOL by controlling the direction of the airflow from the thruster 201. In another example, the first flap 210A is configured to pivot about the attachment point to the trailing edge of the upper wing portion 230 and is further configured to control the area of the exhaust outlet of the thruster 201, thereby controlling the mass flow rate conditions for efficient fan operation and thus increasing thrust. In some embodiments, each flap 210 is a single-element flap. In other embodiments, a part of the flap 210 is a multi-element flap.

[0032] Furthermore, the wing 103 with ducts increases the lift during low-speed cruise from the conventional CLmax of 1.8 to 6.0 or more. This enables a three-fold higher wing loading while reducing the wing area to one-third compared to the conventional wing design. Also, by directly integrating the duct into the airfoil leading edge of the wing 103 with ducts, the drag during high-speed cruise is reduced (e.g., improved by 40% or more) compared to the conventional wing design. The high lift is achieved without adding a high pitching moment. Further, by integrating the duct into the jet foil leading edge of the wing 103 with ducts, the ride comfort is improved, and a low stall speed of 61 knots is enabled with a takeoff / landing balanced runway length of less than 3000.

[0033] The continuously arranged jet foils 109 included in the wing 103 with ducts enhance the lift of the wing over a plurality of speed ranges and provide thrust throughout the flight envelope. By embedding the continuously arranged jet foils 109 into the wing 103 with ducts, the drag can be reduced while maximizing the efficiency of the generated thrust. In some embodiments, the wing 103 with ducts also includes ailerons for roll control and additional flaps for trim over various stages of flight.

[0034] The flap 210 includes both a first flap 210A at the upper part of the trailing edge of the wing 103 with ducts (e.g., the upper wing part 230) and a second flap 210B at the lower part of the trailing edge of the wing 103 with ducts, and can adjust the area ratio of the exhaust to match a specific cruise speed and deflect the exhaust flow so that it does not deviate from the upper surface of the lower wing. By adjusting the area ratio, the efficiency can be improved at any cruise speed without the need for a variable pitch propeller wing. In one embodiment, the deflection of the flap 210 may be automatically performed mechanically or electronically as a function of the airspeed.

[0035] Since the thrusters are incorporated into the leading edge of the ducted wing 103, the upper wing section 230 and the lower wing section 250 function like a compound aircraft where the vertical portion of the duct array enhances the structural rigidity. As shown in Figure 2, the lower wing section 250 incorporates a thruster longer than the upper wing section 230 such that the end of the flap 210A attached to the upper wing section 230 extends beyond the lower wing section 250 at the leading edge of the ducted wing 103, which also has the effect of reducing fluid distortion on the thruster 201 surface regardless of the angle of attack or flight speed. Incorporating the ducted wing 103 behind the leading edge is important because it requires additional pylons to avoid boundary layer intrusion, resulting in increased drag.

[0036] Due to the complex integration, a ducted wing 103 is formed with a primary wing spar and at least two secondary wing spars for increased rigidity. The ducted wing 103 may be equipped with up to 50 thrusters, for example, to provide multi-engine redundancy. Since these thrusters are each driven by the same signal from a FADEC (Full Authority Digital Engine Control), the pilot can control the thrust of the entire continuously arranged thrusters 201 with a single throttle. The thrusters 201 included in the continuously arranged jet foil 109 are each replaceable. The leading edge of the continuously arranged thrusters 201 is pivotable for maintenance, providing access for maintenance personnel to remove the fan, stator, or electric motor as needed. However, the thrusters 201 themselves do not pivot in each mode of takeoff and landing. Introducing sweep into the ducted wing 103 can align the lift center and thrust center, avoiding a nose-down pitching moment throughout the speed range. Depending on the relative arrangement of the boom and tail fin with respect to the wing closer to the fuselage, structural weight benefits can also be obtained.

[0037] As further described below, each duct of the continuously arranged jet foils 109 is elliptical in shape at the inlet lip, but transitions to a cylindrical cross-section from the fan face to the stator region and then to a rectangular cross-section so that the exhaust of the aircraft 100 adheres smoothly and laminarly to the upper surface of the lower airfoil. The jet foils 109 are specially designed considering the balance of aerodynamic force and thrust without generating pitching moment. Inside the duct, there is a center body that houses an electric motor for driving each thruster 201. Wiring to the motor is done through one or more stators for power and active cooling as needed. In some embodiments, the upper wing portion 230 and the lower wing portion 250 can include one or more payloads such as electronics, sensors, fuel, cargo, or mechanical elements.

[0038] Figures 3A - 3F are different views of an application example of the ducted wing 103 of the aircraft 100 according to some embodiments. As shown in Figures 3A - 3F, the ducted wing 103 includes a plurality of second flaps 210B that are rotatable independently of each other. As shown in Figures 3A - 3F, the flaps 210B rotate to various positions to enable various takeoff modes.

[0039] By arranging the thrusters 201 in series, several control and thrust vectoring possibilities are expanded. The thrust can be varied between the respective thrusters 201 to induce yawing, rolling, and pitching moments. The relative pitch difference in the spanwise direction between the jet foils 109 can be utilized to increase the climb and descent speeds. This can be further enhanced by additional control surfaces installed at the trailing edge.

[0040] The spanwise combination of ducts within the jet foil 109 is suitable for integration along the wing or as the multi-element wing itself. The continuous array can be arranged and extended as a multi-element wing with sweep, stagger, dihedral, and taper, according to the needs of the system. The choice of whether to integrate the continuously arrayed propulsors 201 as a complete multi-element wing depends not only on the relative size of the propulsors 201 but also on the amount of thrust (minus drag) required.

[0041] For example, FIG. 3A shows the position of the second flap 210B on the lower wing portion 250 during CTOL or cruise. As shown in FIGS. 3A, 3E, and 3F, while the aircraft is in the CTOL mode, the second flap 210B is in the first position (e.g., the first angle). The first position of the second flap 210B is optimized for in-flight CTOL or cruise. In one embodiment, the default position of the second flap 210B maximizes the overall length of the ducted wing 103. The second flap 210B may be controlled independently of other flaps 210, such as the first flap 210A, depending on the embodiment.

[0042] FIG. 3B shows the second position of the second flap 210B of the VTOL lower wing portion 250. While the aircraft is in the VTOL mode, the second flap 210B is angled (e.g., pivoted) downward at the maximum pivotable angle (e.g., the second angle) of the second flap 210B to direct the thrust generated by the propulsor 201 downward, as indicated by the arrow 301. By directing the thrust downward, the aircraft 100 is configured for VTOL. In one embodiment, the maximum pivot angle of the second flap 210B is 45 degrees. Using an angle greater than 45 degrees results in reduced efficiency.

[0043] Figures 3C and 3D show the third position of the second flap 210B on the lower wing 250 in STOL mode. In one embodiment, the STOL capability of the aircraft 100 enables the aircraft 100 to take off and clear an obstacle of a predetermined height (e.g., 50 feet) within a predetermined distance (e.g., 1500 feet) from the start of the takeoff roll and then stop within a predetermined distance of 1500 feet. Thus, the aircraft 100 can take off and land when the length of the runway or landing area is relatively short.

[0044] The second flap 210B in STOL mode is in a third position that is an intermediate position between the first position of the second flap 210B for CTOL and the second position of the second flap 210B for VTOL. In one embodiment, the second flap 210B is at an intermediate angle between the maximum pivot angle of the second flap 210B for VTOL and the angle of the second flap 210B for CTOL. Figures 3E and 3F show the second flap 210B on the lower wing 250 for CTOL and are in a position optimized for CTOL as compared to Figures 3C and 3D.

[0045] Note that in CTOL mode, STOL mode, and VTOL mode, the angle of the thruster 201 integrated with the ducted wing 103 is fixed. That is, the thruster 201 does not rotate to change the direction of thrust to enable CTOL, STOL, or VTOL. Rather, the position (e.g., angle) of the second flap 210B changes to enable each mode of the aircraft 100, and the thruster 201 maintains a constant angle between different modes of the aircraft 100.

[0046] Figures 4A and 4B are a perspective view and a cross-sectional view, respectively, of an array of continuous jet foils 109 forming a ducted wing 103 according to one embodiment. Figures 4A and 4B show different jet foils 109 that collectively make up the ducted wing 103. In one embodiment, the array of continuous jet foils 109 includes a first jet foil 109A, a second jet foil 109B, and a third jet foil 109C arranged laterally to form part of the ducted wing 103. The first jet foil 109A includes a first thruster 201A, a first upper wing portion 230A, and a first lower wing portion 250A. The second jet foil 109B includes a second thruster 201B, a second upper wing portion 230B connected to extend from an end of the first upper wing portion 230A of the first jet foil 109A, and a second lower wing portion 250B connected to extend from an end of the first lower wing portion 250A of the first jet foil 109A. Finally, the third jet foil 109C includes a third thruster 201C, a third upper wing portion 230C connected to extend from an end of the second upper wing portion 230B of the second jet foil 109B, and a third lower wing portion 250C connected to extend from an end of the second lower wing portion 250B of the second jet foil 109B. Although three jet foils 109 are shown in Figures 4A and 4B, the array of continuous jet foils 109 may include any number of jet foils.

[0047] In FIGS. 4A and 4B, the connection portions between the first upper wing portion 230A, the second upper wing portion 230B, and the third upper wing portion 230C, as well as the connection portions between the first lower wing portion 250A, the second lower wing portion 250B, and the third lower wing portion 250C, are not straight rectangular lines and edges, but are curved. In these embodiments, the inlets and outlets of the corresponding thrusters 201 may be more conical, and the flaps 210 following their edges may also be curved accordingly. One advantage of such curves is that less material is required, and accordingly the weight is reduced. In other embodiments not shown, the connection between the thrusters 201 may be smoother, in which case the edges between the upper wing portion 230 and the lower wing portion 250 respectively are straight. In this embodiment, since the upper wing portion 230 has a straight edge instead of being curved, and the lower wing portion 250 also has a straight edge instead of being curved, the airflow on the ducted wing 103 becomes more uniform and resembles a two-dimensional flow across the entire ducted wing 103. Furthermore, in this embodiment where the edges are straight, the corresponding flaps 210 match the shape of the edges of the upper wing portion 230 and the lower wing portion 250.

[0048] FIGS. 5A - 5D are cross-sectional views of the jet foil 109 included in the ducted wing 103 according to some embodiments having various flap arrangements. Specifically, FIG. 5A is a cross-sectional view of the jet foil 109 including the aforementioned first flap 210A and second flap 210B. FIG. 5B is a cross-sectional view of the jet foil 109 including a third flap 210C in addition to the first flap 210A and the second flap 20B. FIG. 5C is a cross-sectional view of the jet foil 109 including a fourth flap 210D in addition to the first flap 210A and the second flap 20B. FIG. 5D is a cross-sectional view of the jet foil 109 including both a third flap 210C and a fourth flap 210D in addition to the first flap 210A and the second flap 20B. The plurality of flaps 210 are each controlled independently of each other.

[0049] Referring to FIG. 5A, in one embodiment, each jet foil 109 includes a thruster 201 having an inlet diameter and an outlet diameter. The jet foil 109 includes an inlet 500A having a corresponding inlet diameter and an outlet 500B having a corresponding outlet diameter, and in the default position, the inlet diameter is larger than the outlet diameter.

[0050] The upper wing portion 230 includes a first end 501 and a second end 503 on the opposite side of the first end 501. The lower wing portion 250 also includes a first end 505 and a second end 507 on the opposite side of the first end 505 of the lower wing portion 250. In one embodiment, each of the first end 501 of the upper wing portion 230 and the first end 505 of the lower wing portion 250 is rounded as shown in FIG. 5A.

[0051] In one embodiment, the first end 501 (i.e., the leading edge) of the upper wing portion 230 is in front of the first end 503 (i.e., the leading edge) of the lower wing portion 250. That is, in one embodiment, the first end 501 of the upper wing portion 230 extends beyond the first end 505 of the lower wing portion 250 such that the first end 501 of the upper wing portion 230 does not overlap the first end 505 of the lower wing portion 250. As a result, the inlet surface area of the jet foil 109 is not perpendicular to the air flow but is inclined. The inclined inlet surface area improves the low-speed performance and reduces the distortion of the flow field at the inlet.

[0052] In one embodiment, the upper wing portion 230 has a convex outer surface 509 and a concave inner surface 511. The outer surface 509 of the upper wing portion 230 is not parallel to the inner surface 511 of the upper wing portion 230, as shown in FIG. 5A. In one embodiment, the thickness of the upper wing portion 230 varies from the first end portion 501 of the upper wing portion 230 to the second end portion 503 of the upper wing portion 230. Specifically, the thickness of the upper wing portion 230 increases from the first end portion 501 of the upper wing portion 230 until it reaches the intermediate portion 513 of the upper wing portion 230 that is between the first end portion 501 and the second end portion 503 of the upper wing portion 230. In one embodiment, the intermediate portion 513 corresponds to (e.g., overlaps with) the position of the thruster 201 within the jet foil 109. Thus, in one embodiment, the thickest portion of the upper wing portion 230 is in line with the thruster 201. The thickness of the upper wing portion 230 decreases from the intermediate portion 513 of the upper wing portion 230 to the second end portion 503 of the upper wing portion 230.

[0053] The lower wing portion 250 has an inner surface 515 that faces the inner surface 511 of the upper wing portion 230. The inner surface 515 of the lower wing portion 250 is connected to the inner surface 511 of the upper wing portion 230 and collectively forms the inner surface of the duct of the jet foil 109 in which the thruster 201 is disposed. The inner surface 515 of the lower wing portion 250 includes a concave first portion 519 and a convex second portion 521.

[0054] In one embodiment, the concave first portion 519 of the inner surface 515 of the lower wing portion 250 overlaps with the concave inner surface 511 of the upper wing portion 230. In one embodiment, the concave first portion 519 of the inner surface 51� of the lower wing portion 250 is included in the aforementioned first lower wing portion 250A. The thruster 201 is disposed between the concave first portion 519 of the inner surface 515 of the lower wing portion 250 that forms the duct of the jet foil 109 and the concave portion of the inner surface 511 of the upper wing portion 230. In one embodiment, the duct formed by the upper wing portion 230 and the lower wing portion 250 has the largest inner diameter at the concave first portion 519 of the inner surface 515 of the lower wing portion 250 and the concave inner surface 511 of the upper wing portion 230 that overlaps with the thruster 201. As shown in FIG. 5A, the thruster 201 is closer to the inlet 500A than the outlet 500B of the duct.

[0055] Since the convex second portion 521 of the upper inner surface 515 of the lower wing portion 250 is included in the second lower wing portion 250B, it does not overlap with the upper wing portion 230. Also, the lower wing portion 250 has an outer surface 517. The outer surface 517 of the lower wing portion 250 is convex in shape from the first end portion 505 of the lower wing portion 250 to the second end portion 507 of the lower wing portion 250 in one embodiment.

[0056] In one embodiment, the thickness of the lower wing portion 250 varies from the first end portion 505 of the lower wing portion 250 to the second end portion 507 of the lower wing portion 250. Specifically, the thickness of the lower wing portion 250 increases from the first end portion 505 of the lower wing portion 250 to the middle portion 523 of the lower wing portion 250 corresponding to (e.g., overlapping) the second end portion 503 of the upper wing portion 230. Thus, the thickest portion of the lower wing portion 250 is aligned with the second end portion 503 of the upper wing portion 230. The thickness of the lower wing portion 250 decreases from the middle portion 523 of the lower wing portion 250 toward the second end portion 507 of the lower wing portion 250.

[0057] As a result of both the inner surface 511 of the upper wing portion 230 and the inner surface 515 of the lower wing portion 250 being uneven, the inner diameter (and thus the area) of the duct of the jet foil varies from both the first end portion 501 of the upper wing portion 230 and the first end portion 505 of the lower wing portion 250 to the second end portion 503 of the upper wing portion 230 and the middle portion 523 of the lower wing portion 250. As shown in FIG. 5A, the diameter (and thus the area) of the duct increases from the inlet 500A of the jet foil to the portion of the duct overlapping the middle portion 513 of the upper wing portion, and decreases from the middle portion 513 to the outlet 500B of the duct between the second end portion 503 of the upper wing portion 230 and the middle portion 523 of the lower wing portion 250.

[0058] As described above, one or more flaps 210 may be connected to the jet foil 109. In FIG. 5A, the second end 503 of the upper wing portion 230 includes a first flap 210A, and the second end 507 of the lower wing portion 250 includes a second flap 210B. The first flap 210A is configured to control the exit area of the exit 500B (e.g., the exhaust port) of the jet foil 109. The area of the exit 500B can be decreased from its maximum area to its minimum area by pivoting the first flap 210A downward, thereby changing the angle of the first flap 210A and changing the diameter of the exit. By controlling the exit area of the jet foil 109, the air flow of the aircraft 100 can be optimized in various speed ranges, and maximum efficiency can be obtained.

[0059] In contrast, the second flap 210B controls the direction of the exhaust flow, thereby changing the direction of the thrust. As described above, the angle (e.g., position) of the second flap 210B corresponds to a specific mode of the aircraft 100. In FIG. 5A, the angle of the second flap 210B corresponds to the CTOL mode, but the second flap 210B may be angled downward to a maximum angle corresponding to the VTOL mode of the aircraft 100 or an intermediate angle corresponding to the STOL mode of the aircraft 100.

[0060] FIG. 5B shows another embodiment of the jet foil 109. The embodiment shown in FIG. 5B is similar to the embodiment shown in FIG. 5A. Therefore, descriptions of the components common to both the embodiments of FIGS. 5A and 5B are omitted respectively.

[0061] In the embodiment of FIG. 5B, a third flap 210C is added to the first end 501 of the upper wing portion 230. Thus, the jet foil 109 of FIG. 5B includes a first flap 210A at the second end 503 of the upper wing portion 230, a second flap 210B at the second end 507 of the lower wing portion 250, and a third flap 210C at the first end 501 of the upper wing portion 230. The first flap 210A and the second flap 210B perform the same functions as described above with respect to FIG. 5A. The third flap 210C may be configured to be arranged at different angles in order to change the inlet area of the inlet 500A of the jet foil 109. For example, the angle of the third flap 210C can be changed downward toward the center of the thruster 201 to control the inlet area of the inlet 500A of the jet foil 109. By controlling such an inlet area in addition to the outlet area of the jet foil 109, the inlet air flow of the aircraft 100 is further optimized in various speed ranges, and the efficiency is maximized.

[0062] FIG. 5C shows another embodiment of the jet foil 109. The embodiment shown in FIG. 5C is the same as the embodiment shown in FIG. 5A. Therefore, descriptions of the components common to both the embodiments of FIGS. 5A and 5C are omitted respectively.

[0063] In the embodiment of FIG. 5C, a fourth flap 210D is added to the first end 505 of the lower wing portion 250. Thus, the jet foil 109 of FIG. 5C includes a first flap 210A at the second end 503 of the upper wing portion 230, a second flap 210B at the second end 507 of the lower wing portion 250, and a fourth flap 210D at the first end 505 of the lower wing portion 250. The first flap 210A and the second flap 210B perform the same functions as described above with respect to FIG. 5A. The fourth flap 210D may be configured to be arranged at a different angle to change the inlet area of the inlet 500A of the jet foil 109. For example, the angle of the fourth flap 210D can be changed upward toward the center of the thruster 201 to control the inlet area of the inlet 500A of the jet foil 109. By controlling such inlet area in addition to the outlet area of the jet foil 109, the inlet air flow of the aircraft 100 is further optimized in various speed ranges and the efficiency is maximized.

[0064] FIG. 5D shows yet another embodiment of the jet foil 109. The embodiment shown in FIG. 5D is similar to the embodiments shown in FIGS. 5A-5C. Accordingly, descriptions of the components common to any of the embodiments of FIGS. 5A-5C are omitted.

[0065] In the embodiment of FIG. 5C, the third flap 210C is added to the first end 503 of the upper wing portion 230, and the fourth flap 210D is added to the first end 505 of the lower wing portion 250. Accordingly, the jet foil 109 of FIG. 5D includes the first flap 210A at the second end 503 of the upper wing portion 230, the second flap 210B at the second end 507 of the lower wing portion 250, the third flap 210C at the first end 501 of the upper wing portion 230, and the fourth flap 210D at the first end 505 of the lower wing portion 250. The first flap 210A and the second flap 210B perform the same functions as described above with respect to FIG. 5A. The third flap 210C and the fourth flap 210D may be configured to be arranged at different angles to change the inlet diameter of the inlet 500A of the jet foil 109, and thus change the inlet area of the inlet 500A of the jet foil 109. By having both the third flap 210C and the fourth flap 210D, the adjustment range of the inlet area of the inlet 500A of the jet foil 109 is widened as compared with the embodiments of FIGS. 5B and 5C. 5B and 5C having a single flap 210 at the inlet of the jet foil 109 can further optimize the inlet air flow in various speed ranges of the aircraft 100.

[0066] In one embodiment, the wing 103 with ducts may include a control mechanism connected to each flap 210 to control the angle of the flap 210. The control mechanism may include a servo motor and a rod in one embodiment. One end of the rod is connected to the servo motor, and the second end of the rod is connected to the flap 210B. The servo motor can extend the rod to pivot the flap 210 to the maximum movable angle, and can also contract the rod to return the rod to the default position.

[0067] FIGS. 6A-6C are various top views and side views of the fuselage 101 of the aircraft 100 configured to carry passengers 610 and cargo 620 according to some embodiments. As shown in FIGS. 6A-6C, the aircraft 100 can include one or more passengers 610 disposed at the front of the fuselage 101.

[0068] Figures 7A - 7E are top and side views of the fuselage 101 of an aircraft 100 configured to carry passengers 610 according to one embodiment. In the example shown here, two pilots are located at the front of the fuselage 101, and a security divider separates the passenger cabin. The passengers 610 sit in two compartments in one embodiment. The first compartment has club seats, and larger passengers can sit in the row closest to the pilots, thereby improving the weight balance throughout the seat layout. The rear-facing seats enabled by the club seats necessarily improve the safety of the pilots.

[0069] In one embodiment, the rear cabin compartment is equipped with two-person seats facing the rear. In order to improve visibility from these seats, a wide-view window can also be provided at the rear end of the fuselage 101.

[0070] The five-seater configuration is similar to the passenger configuration shown in each figure, except that the rear cabin is removed, two rows of club seats each have two seats, and the pilot compartment can only accommodate one pilot. The nine-seater configuration can be reconfigured to accommodate smaller individuals traveling in groups of twelve (for example, when a family wishes to fly). When the backrests of the co-pilot seats in each row are folded down, a luggage compartment appears. These backrests can be folded to allow large carry-on luggage to be transported in the cabin.

[0071] References in the specification to "one embodiment" or "an embodiment" mean that a particular feature, structure, or characteristic is included in at least one embodiment of the present disclosure. The appearance of the phrase "in one embodiment" in various places in the specification does not necessarily refer to the same embodiment.

[0072] Although the present disclosure has been specifically shown and described with reference to one embodiment and several alternative embodiments, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention.

Claims

1. A ducted wing configured to be attached to an aircraft, wherein the ducted wing is A plurality of ducted fans are integrated with the leading edge of the ducted wing, each of which is connected to at least one other ducted fan to collectively form the ducted wing, each ducted fan forms a duct between its upper and lower wing portions, and each ducted fan is An upper wing portion connected to the upper wing portions of adjacent duct fans of the plurality of duct fans, the upper wing portion having a first leading edge, a trailing edge opposite to the first leading edge, an outer surface between the first leading edge and the trailing edge of the upper wing portion, and an inner surface opposite to the outer surface of the upper wing portion, between the first leading edge and the trailing edge of the upper wing portion, A lower wing portion having the leading edge portion of the ducted wing, the lower wing portion having a second leading edge, a trailing edge on the opposite side of the second leading edge of the lower wing portion and extending beyond the trailing edge of the upper wing portion, an outer surface between the second leading edge and the trailing edge of the lower wing portion, and an inner surface extending from the inner surface of the upper wing portion and forming a duct within the duct fan, wherein the duct includes a lower wing portion extending from the first leading edge of the upper wing portion and the second leading edge of the lower wing portion to the trailing edge of the upper wing portion and to the intermediate portion of the lower wing portion between the second leading edge and the trailing edge of the lower wing portion, and a plurality of duct fans. Includes, A thruster fan provided within the duct of the duct fan, the thruster fan being positioned between the upper wing portion and the lower wing portion, and including a thruster fan that is closer to the first leading edge of the upper wing portion and the second leading edge of the lower wing portion than to the trailing edge of the upper wing portion, The diameter of the duct changes from the second leading edge of the upper wing and the lower wing to the trailing edge of the upper wing and the intermediate portion of the lower wing. Each of the propulsion fans of the plurality of ducted fans has a ducted blade that is angled in a certain direction with respect to the chord line of the lower wing portion of the ducted fan.

2. The ducted wing according to claim 1, wherein the trailing edge of the upper wing portion is configured to change the diameter of the outlet of the duct defined between the trailing edge of the upper wing portion and the intermediate portion of the lower wing portion.

3. The ducted wing according to claim 2, wherein the first flap is configured to change the diameter of the outlet of the duct by pivoting between a first position corresponding to a first angle of the first flap and a second position of the first flap corresponding to a second angle greater than the first angle.

4. The ducted wing according to claim 2, wherein the trailing edge of the lower wing portion includes a second flap, the second flap being configured to pivot between a first position corresponding to a first angle of the second flap associated with the normal takeoff and landing mode of the aircraft, a second position greater than the first angle of the second flap and corresponding to a second angle of the second flap associated with the vertical takeoff and landing mode of the aircraft, and a third position between the first and second angles of the second flap and corresponding to a third angle of the second flap associated with the short takeoff and landing mode of the aircraft.

5. The ducted wing according to claim 4, wherein at least one of the first leading edge of the upper wing or the second leading edge of the lower wing includes at least one flap configured to change the diameter of the inlet of the duct defined between the first leading edge of the upper wing and the second leading edge of the lower wing.

6. The ducted wing according to claim 5, wherein each of the at least one flaps is configured to change the diameter of the inlet of the duct by pivoting between a first position corresponding to a first angle of the at least one flap and a second position of the at least one flap corresponding to a second angle greater than the first angle of the at least one flap.

7. The ducted wing according to claim 1, wherein the first leading edge of the upper wing extends beyond the second leading edge of the lower wing so that the first leading edge of the upper wing does not overlap with the second leading edge of the lower wing.

8. The ducted wing according to claim 1, wherein the outer surface of the upper wing portion is convex between the first leading edge and the trailing edge of the upper wing portion, and the inner surface of the upper wing portion is concave between the first leading edge and the trailing edge of the upper wing portion.

9. The ducted wing according to claim 8, wherein the thickness of the upper wing portion increases from the first leading edge of the upper wing portion to the intermediate portion of the upper wing portion located between the first leading edge and the trailing edge of the upper wing portion, and the thickness of the upper wing portion decreases from the intermediate portion to the trailing edge of the upper wing portion.

10. The ducted wing according to claim 9, wherein the outer surface of the lower wing portion is convex between the second leading edge and the trailing edge of the lower wing portion, the first portion of the inner surface of the lower wing portion is concave between the second leading edge and the intermediate portion of the lower wing portion, and the second portion of the inner surface of the lower wing portion is convex between the intermediate portion and the trailing edge of the lower wing portion.

11. The ducted wing according to claim 10, wherein the thickness of the lower wing portion increases from the second leading edge of the lower wing portion to the middle portion of the lower wing portion, and decreases from the middle portion of the lower wing portion to the trailing edge of the lower wing portion.

12. The ducted wing according to claim 11, wherein the intermediate portion of the lower wing is aligned with the trailing edge of the upper wing.

13. It is an aircraft, Torso and, A plurality of ducted wings connected to the fuselage, each of the plurality of ducted wings including a ducted fan integrally and continuously arranged to generate thrust, Multiple booms, each boom being attached to the end of a corresponding ducted wing from the multiple ducted wings, A plurality of horizontal stabilizers, each of which is connected to the end of a corresponding boom from the plurality of booms, The aforementioned continuously arranged and integrated duct fans form a duct between the upper and lower blades of the duct fan, and each duct fan is An upper wing portion having a first leading edge, a trailing edge opposite to the first leading edge, an outer surface between the first leading edge and the trailing edge of the upper wing portion, and an inner surface opposite to the outer surface of the upper wing portion, A lower wing having a second leading edge, a trailing edge on the opposite side of the second leading edge of the lower wing and extending beyond the trailing edge of the upper wing, an outer surface between the second leading edge and the trailing edge of the lower wing, and an inner surface extending from the inner surface of the upper wing and forming a duct within the duct fan, wherein the duct extends from the upper wing and the second leading edge of the lower wing to the trailing edge of the upper wing and the intermediate portion of the lower wing between the second leading edge and the trailing edge of the lower wing, A thruster fan provided within the duct of the duct fan, the thruster fan being positioned between the upper wing portion and the lower wing portion, and including a thruster fan that is closer to the first leading edge of the upper wing portion and the second leading edge of the lower wing portion than to the trailing edge of the upper wing portion, An aircraft in which the diameter of the duct changes from the first leading edge of the upper wing and the second leading edge of the lower wing to the trailing edge of the upper wing and the middle portion of the lower wing.

14. The plurality of vertical stabilizers further include a plurality of vertical stabilizers, each connected to the end of a corresponding boom from the plurality of booms, The aircraft according to claim 13.

15. The aircraft according to claim 13, wherein the trailing edge of the upper wing portion is configured to change the diameter of the outlet of the duct defined between the trailing edge of the upper wing portion and the intermediate portion of the lower wing portion.

16. The aircraft according to claim 15, wherein the first flap is configured to change the diameter of the outlet of the duct by pivoting between a first position corresponding to a first angle of the first flap and a second position of the first flap corresponding to a second angle greater than the first angle.

17. The aircraft according to claim 15, wherein the trailing edge of the lower wing portion includes a second flap, the second flap being configured to pivot between a first position corresponding to a first angle of the second flap associated with the normal takeoff and landing mode of the aircraft, a second position greater than the first angle of the second flap and corresponding to a second angle of the second flap associated with the vertical takeoff and landing mode of the aircraft, and a third position between the first and second angles of the second flap and corresponding to a third angle of the second flap associated with the short takeoff and landing mode of the aircraft.

18. The aircraft according to claim 17, wherein at least one of the first leading edge of the upper wing or the second leading edge of the lower wing includes at least one flap configured to change the diameter of the inlet of the duct defined between the first leading edge of the upper wing and the second leading edge of the lower wing.

19. The aircraft according to claim 18, wherein each of the at least one flaps is configured to change the diameter of the inlet of the duct by pivoting between a first position corresponding to a first angle of the at least one flap and a second position of the at least one flap corresponding to a second angle greater than the first angle of the at least one flap.

20. The aircraft according to claim 13, wherein the first leading edge of the upper wing extends beyond the second leading edge of the lower wing so that the first leading edge of the upper wing does not overlap with the second leading edge of the lower wing.

21. The aircraft according to claim 13, wherein the outer surface of the upper wing portion is convex between the first leading edge and the trailing edge of the upper wing portion, and the inner surface of the upper wing portion is concave between the first leading edge and the trailing edge of the upper wing portion.

22. The aircraft according to claim 21, wherein the thickness of the upper wing portion increases from the first leading edge of the upper wing portion to the intermediate portion of the upper wing portion located between the first leading edge and the trailing edge of the upper wing portion, and the thickness of the upper wing portion decreases from the intermediate portion to the trailing edge of the upper wing portion.

23. The aircraft according to claim 22, wherein the outer surface of the lower wing portion is convex between the second leading edge and the trailing edge of the lower wing portion, the first portion of the inner surface of the lower wing portion is concave between the second leading edge and the middle portion of the lower wing portion, and the second portion of the inner surface of the lower wing portion is convex between the middle portion and the trailing edge of the lower wing portion.

24. The aircraft according to claim 23, wherein the thickness of the lower wing portion increases from the second leading edge of the lower wing portion to the middle portion of the lower wing portion, and decreases from the middle portion of the lower wing portion to the trailing edge of the lower wing portion.

25. The aircraft according to claim 24, wherein the intermediate portion of the lower wing is aligned with the trailing edge of the upper wing.

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