Systems and methods for powered flying vehicles

Abstract

The air vehicle includes a frame, a propulsion system coupled to the frame, a first power source coupled to the frame and configured to power the propulsion system, traction wheels coupled to the frame and configured to engage in tractive engagement with a ground surface during low-speed ground operation of the air vehicle, and a second power source coupled to the frame and configured to power the traction wheels.

Description

[Technical Field]

[0001] (Related Applications) This application claims the benefit of and priority to U.S. Provisional Patent Application No. 63 / 367,128, entitled "FLYING BICYCLE," filed June 28, 2022, which is incorporated herein by reference in its entirety.

[0002] The field of the disclosure relates generally to electrically powered flight vehicles, and more particularly to systems and methods for augmenting electrically powered flight vehicles during ground operations. [Background technology]

[0003] Propeller-based aircraft operate under efficiency constraints imposed by the pitch of the propeller blades. For example, the optimal blade pitch for cruise is quite different from the optimal blade pitch for runway acceleration and takeoff. Typical fixed-pitch propellers compromise both cruise and takeoff performance to obtain a blend that only partially reduces the propeller's performance in each situation. Thus, known aircraft equipped with fixed-pitch propellers optimized to avoid cruise compromise penalties cannot rapidly accelerate and decelerate for short takeoffs and landings because the propeller design significantly sacrifices takeoff performance. Variable-pitch propellers were designed to solve this problem, but the mechanisms for varying the propeller pitch are heavy and mechanically complex, imposing their own efficiency penalties, especially on lightweight aircraft. The penalties imposed by variable-pitch propellers are magnified when attempting to distribute many propulsion devices along the wing span.

[0004] Additionally, electric aircraft utilize distributed electric propulsion systems to distribute thrust and fly at much slower forward speeds, minimizing the risk of injury to crew members. Distributed electric propulsion systems can generate more lift for a given wing area. Higher wing loadings and smaller wings result in a more comfortable ride. However, powered drift aircraft struggle to achieve short landing distances due to the high thrust that must be provided by the propellers upon arrival. Summary of the Invention

[0005] This Summary is provided to introduce a selection of concepts in a simplified form further described below in the Detailed Description. This Summary is not intended to identify key features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

[0006] Disclosed herein are novel embodiments of air vehicles that include an electric power source, either without pedals (such as a motorcycle) or with pedals integrated into the electric power source (such as an electric bicycle), that directly drives the wheels of the air vehicle. The motor can generate high torque at low speeds, allowing the wheels to accelerate the air vehicle quickly and efficiently by traction with the ground without relying on low-speed thrust from a propeller. Because reliance on the propeller for takeoff thrust is reduced or eliminated, a fixed propeller pitch can be selected to increase efficiency during cruise. In some embodiments, the resulting efficiency improvement is in the range of 5-10% compared to a fixed-pitch propeller with a pitch selected to facilitate both takeoff and cruise.

[0007] Additionally, novel embodiments of control surfaces implemented by wheel fairings are disclosed herein. The wheel fairings can function as speed brakes to generate drag during approach to landing or deceleration on the landing surface, significantly reducing the ground area required for landing. The wheel fairings also reduce wheel drag during ground operations. The wheel fairing control surfaces can also provide limited manual control authority to the air vehicle operator while an automatic flight control system maintains stable flight path control via electric propulsors.

[0008] In one aspect, an air vehicle is provided that includes a frame, a propulsion system coupled to the frame, a first power source coupled to the frame and configured to power the propulsion system, traction wheels coupled to the frame and configured for tractional engagement with a surface during low-speed ground operation of the air vehicle, and a second power source coupled to the frame and configured to power the traction wheels.

[0009] In another aspect, an air vehicle is provided that includes a frame, a propulsion system coupled to the frame, a first power source coupled to the frame and configured to power the propulsion system, a guidance wheel pivotally coupled to the frame and configured to steer the air vehicle during ground operations, and a guidance wheel fairing coupled to the frame at least partially enclosing the guidance wheel and configured to pivot with the guidance wheel, the guidance wheel fairing operable as a control surface for the air vehicle.

[0010] In another aspect, an air vehicle is provided. The air vehicle includes a frame, a guidance wheel pivotally coupled to the frame, a guidance wheel fairing configured to at least partially surround and pivot around the guidance wheel, and at least one manual control configured to orient the guidance wheel fairing in response to operation by a human operator on board the air vehicle. The orientation is selectable to set the air vehicle's orientation during flight. The air vehicle also includes a plurality of propulsion devices coupled to the frame and a controller coupled to the frame. The controller includes at least one processor in communication with a memory and operably coupled to the plurality of propulsion devices, the memory storing executable instructions for causing the processor to automatically maintain level flight during flight. [Brief explanation of the drawings]

[0011] A more particular description of the principles briefly described above will be made by reference to specific embodiments thereof, which are illustrated in the accompanying drawings. The principles herein will be described and explained with additional specificity and detail through the use of the accompanying drawings, with the understanding that these drawings depict only exemplary embodiments of the present disclosure and are therefore not to be considered limiting of its scope. [Figure 1A] FIG. 1A is a schematic perspective view of an air vehicle according to an embodiment of the present disclosure. [Figure 1B] FIG. 1B illustrates a schematic bottom view of the air vehicle of FIG. 1A in accordance with an embodiment of the present disclosure. [Figure 1C] FIG. 1C is a schematic perspective view of the air vehicle of FIG. 1A illustrating the airframe and alternative propulsion system according to an embodiment of the present disclosure. [Figure 2A] FIG. 2A is a schematic block diagram of a power system of the air vehicle of FIG. 1A, according to an embodiment of the present disclosure. [Figure 2B] FIG. 2B illustrates another schematic block diagram of the power system of the air vehicle of FIG. 1A in accordance with an embodiment of the present disclosure. [Figure 3]FIG. 3 is a table of example control characteristics corresponding to each degree of freedom of the air vehicle of FIG. 1A according to an embodiment of the present disclosure. [Figure 4] FIG. 4 illustrates an exemplary controller data flow that may be used by the air vehicle controller shown in FIG. 1A. [Figure 5] FIG. 5 is a schematic block diagram of a computer system in which other aspects of the present disclosure can be implemented. DETAILED DESCRIPTION OF THE INVENTION

[0012] Various exemplary embodiments of the present disclosure are described in detail below. While specific implementations are described, it should be understood that this description is for illustrative purposes only. Those skilled in the relevant art will recognize that other components and configurations may be used without departing from the spirit and scope of the present disclosure. Accordingly, the following description and drawings are illustrative and should not be construed as limiting. Numerous specific details are set forth to provide a thorough understanding of the present disclosure. However, in certain instances, well-known or conventional details are not set forth to avoid obscuring the description. References to one or an embodiment in this disclosure may refer to the same embodiment or any embodiment. Such references refer to at least one of the exemplary embodiments.

[0013] Reference to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of the present disclosure. Appearances of the phrase "in one embodiment" in various places throughout this specification do not necessarily all refer to the same embodiment or to separate or alternative exemplary embodiments that are mutually exclusive of other exemplary embodiments. Furthermore, various features are described that are exhibited by some exemplary embodiments and not by other exemplary embodiments. Features of one example may be combined with and used in conjunction with other features of other examples.

[0014] The terms used herein generally have their ordinary meaning in the art, within the context of this disclosure and in the specific context in which each term is used. Alternative and synonymous terms may be used for any one or more of the terms discussed herein, and no special significance should be attached to whether a term is recited or discussed herein. In some cases, synonyms for particular terms are provided. The recitation of one or more synonyms does not preclude the use of other synonyms. The use of examples anywhere in this specification, including examples of any term discussed herein, is for illustrative purposes only and is not intended to further limit the scope and meaning of the disclosure or any exemplified term. Similarly, the present disclosure is not limited to the various exemplary embodiments provided herein.

[0015] Without intending to limit the scope of the present disclosure, examples of instruments, devices, methods, and their associated results according to exemplary embodiments of the present disclosure are set forth below. It should be noted that titles or subtitles may be used in the examples for the convenience of the reader, but should in no way limit the scope of the disclosure. Unless otherwise defined, technical and scientific terms used herein have the meanings commonly understood by those skilled in the art to which this disclosure pertains. In the case of conflict, the present specification, including definitions, will control.

[0016] Additional features and advantages of the present disclosure will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the principles disclosed herein. The features and advantages of the present disclosure may be realized and obtained by means of the instruments and combinations particularly pointed out in the appended claims. These and other features of the present disclosure will become more fully apparent from the following description and the appended claims, or may be learned by practice of the principles described herein.

[0017] For clarity of explanation, in some examples, the technology may be presented as including individual functional blocks that represent devices, device components, steps or routines in a software-implemented method, or a combination of hardware and software.

[0018] In the figures, some structural or method features may be shown in a particular arrangement and / or order. However, it should be understood that such a particular arrangement and / or order may not be required. Rather, in some embodiments, such features may be arranged in a different manner and / or order than that shown in the illustrative figures. Furthermore, the inclusion of a structural or method feature in a particular figure does not imply that such feature is required in all embodiments, and some embodiments may not include other features or may be combined with other features.

[0019] As used herein, ordinal terms (e.g., "first," "second," "third," etc.) used to modify elements such as structures, components, operations, etc., do not by themselves indicate a priority or order of the element relative to another element, but rather merely distinguish the element from another element having the same name (using the ordinal term).

[0020] While the concepts of the present disclosure are susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and are herein described in detail, It should be understood, however, that there is no intention to limit the concepts of the present disclosure to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the scope of this disclosure and the appended claims.

[0021] FIG. 1A is a schematic perspective view of an exemplary embodiment of air vehicle 100, and FIG. 1B is a bottom view of air vehicle 100. In some embodiments, air vehicle 100 is an ultralight vehicle. An "ultralight air vehicle" refers to a vehicle that is certified as an ultralight vehicle under Title 14, Chapter 103 of the United States Code of Federal Regulations ("14 CFR Part 103"). For example, to comply with 14 CFR Part 103, as amended in June 2023, a powered air vehicle must weigh less than 254 pounds, have a fuel capacity not exceeding 5 U.S. gallons, be unable to fly at a horizontal flight speed greater than 55 knots, and have a power-off stall speed of 24 knots or less.

[0022] In some embodiments, air vehicle 100 meets some, but not all, of the requirements for an ultralight vehicle. For example, but not by way of limitation, an exception may be obtained from 14 CFR Part 103 for a home-built vehicle that does not meet the requirements of weighing less than 254 pounds, having a fuel capacity not exceeding 5 U.S. gallons, and being unable to achieve a horizontal flight speed greater than 55 knots, but having a power-off stall speed of 24 knots or less.

[0023] In some embodiments, the air vehicle 100 is a light sport aircraft. A "light sport aircraft" refers to a vehicle that meets the definition of a "light sport aircraft" provided in Title 14 of the Code of Federal Regulations, Section 1.1 ("14 CFR 1.1"). For example, to meet 14 CFR 1.1, as amended in June 2023, a light sport aircraft must have a maximum takeoff weight of 1,320 pounds or less for aircraft not intended for operation over water (1,430 pounds for aircraft intended for operation over water), a maximum airspeed in full continuous power level flight of 120 knots or less under standard atmospheric conditions at sea level, and a maximum stall speed or minimum steady flight speed without the use of lift augmentation devices (VS1) of 45 knots or less at the aircraft's maximum certified takeoff weight and critical center of gravity.

[0024] In some embodiments, the air vehicle 100 meets some, but not all, of the requirements of a light sports vehicle.

[0025] Embodiments of air vehicle 100 other than those described above in terms of FAA regulations are contemplated.

[0026] The air vehicle 100 may include a frame 102 configured to provide structural support for other components of the air vehicle 100. In some embodiments, the frame 102 is formed substantially from steel. Additionally or alternatively, the frame 102 may include one or more of aluminum or carbon fiber reinforced composite material. However, other materials for the frame 102 are also contemplated. In the illustrated embodiment, the frame includes multiple elongated members 146 bonded together. In some embodiments, the elongated members 146 may be extendable to accommodate riders of different heights. Other constructions for the frame 102 are also contemplated.

[0027] The air vehicle 100 can also include at least one wing 108 coupled to the frame 102. In some embodiments, the at least one wing 108 includes two wings 108, each defined as extending from either side of the frame 102 along the span dimension S of the air vehicle. (In other words, "two wings" does not simply refer to a single left wing paired with a single right wing.) For example, in the illustrated embodiment, the two wings 108 are forward wings 108 and aft wings 108, with "forward" and "aft" defined relative to the longitudinal dimension L of the air vehicle. In some embodiments, the use of two wings 108, combined with the distribution of the propulsion units 106 along the span dimension S of both wings, as described below, facilitates achieving required lift performance while the width of the air vehicle along the span dimension is substantially reduced relative to the width of known ultralight or similar air vehicles. For example, known ultralight vehicles typically have widths of 17 feet or more. In contrast, embodiments of the air vehicle 100 having a forward wing and aft wing 108 may have a width along the span dimension of no more than 12 feet, advantageously allowing the air vehicle 100 to be accommodated in a 12-foot-wide highway lane or a trailer built for use in such a lane. Further, in some such embodiments, an air vehicle 100 having two wings 108 may have a width along the span dimension of no more than 9 feet, advantageously allowing the air vehicle 100 to be easily accommodated in a 10-foot-wide highway lane or a trailer built for use in such a lane. Additionally or alternatively, the forward wing 108 may include a slot 150 defined therein for receiving a portion of the traction wheel 118 therein with a clearance fit, advantageously allowing the length of the air vehicle 100 to be reduced along the longitudinal dimension L (by allowing the longitudinal length of the forward wing 108 to overlap the position of the traction wheel 118).In some embodiments, the forward wings 108 can be positioned low to the ground (e.g., the ratio of the forward wing 108's height above the ground to the forward wing 108's chord length can be less than 0.5), which helps maximize ground effect. "Ground effect" refers to the reduction in aerodynamic drag generated by a fixed wing when the wing is in close proximity to a fixed surface. Increasing ground effect correspondingly reduces takeoff distance and also reduces friction forces during ground operation, maximizing range during ground operation. Other numbers and arrangements of the at least one wing 108 are also contemplated.

[0028] In some embodiments, the at least one wing 108 may be formed from a Dacron wing skin covering a wing box formed from, for example, steel or aluminum, although other materials for the at least one wing 108 are also contemplated.

[0029] At least one wing 108 may include additional features that promote improved stability of the air vehicle 100. For example, in the illustrated embodiment, the at least one wing 108 includes rigid winglets 124 extending along the vertical dimension V from opposite tips of the wing. Additionally or alternatively, the at least one wing 108 may include one or more control flaps 126 actuable for stability or guidance, either manually by a human operator 134 or automatically by an onboard avionics package 216 (shown in FIG. 2A ). Other implementations of stability and guidance functions are also contemplated. For example, without limitation, the air vehicle 100 may include circulation control features (such as wing clearances or micro-compressors, not shown) to prevent or reduce flow separation over the wing 108 or fuselage 164, thereby improving lift coefficients, such as at high angles of attack.

[0030] The air vehicle 100 may also include a propulsion system 104 coupled to the frame 102 and configured to power the air vehicle 100 during flight. In the illustrated embodiment, the propulsion system 104 is indirectly coupled to the frame 102 by attaching the propulsion system to at least one wing 108. For example, the propulsion system 104 may include one or more propulsion units 106, each of which may be housed in a nacelle 140 affixed to a bottom surface 142 of the at least one wing 108. However, other implementations of coupling the propulsion system 104 to the frame 102 are contemplated.

[0031] In some embodiments, the propulsion system 104 includes multiple propulsion units 106. For example, as described above, the propulsion units 106 can be distributed along the span dimension S of each wing 108 to improve the lift performance of the air vehicle 100. In the illustrated embodiment, each propulsion unit 106 is implemented as a fixed-pitch propeller 156, avoiding the weight and complexity penalties of a variable-pitch propeller, as described above. However, other implementations of the propulsion units 106 are contemplated. For example, as shown in another exemplary embodiment of the air vehicle 100 in FIG. 1C , the propulsion units 106 can be implemented as ducted fans 158. In this case, each propulsion unit 106 includes a fan 160 surrounded by a duct 162 to improve efficiency. Additionally or alternatively, the propulsion units 106 can each include a stator (not shown) positioned aft of the propeller or fan. These types of propulsion units 106 are heavier than fixed-pitch propellers 156 and may be used, for example, in a light-sport aircraft implementation of the air vehicle 100. However, these examples of propulsion device types and aircraft use cases are not intended to be limiting.

[0032] In some embodiments, the propulsion devices 106 are electrically powered. The use of electrically powered propulsion devices 106 may allow for reduced weight, noise, and complexity of the air vehicle 100, for example, as compared to internal combustion engines. However, other implementations of the propulsion devices 106 are also contemplated.

[0033] The air vehicle 100 may also include a first power source 110 coupled to the frame 102 and configured to power the propulsion system 104. For example, the first power source 110 may include one or more propulsion batteries 148 configured to power the propulsion system 104. In some embodiments, the propulsion batteries 148 may be distributed along at least one wing 108 to improve redundancy and reliability of the first power source 110 and reduce wing structural weight. For example, in the illustrated embodiment, at least one propulsion battery 148 is located in each nacelle 140 (for clarity, only one propulsion battery location is shown in FIG. 1B , but it should be understood that other nacelles 140 or airframe 164 may also house propulsion batteries 148). Other numbers or locations of propulsion batteries 148 are also contemplated, an example of which is shown in FIG. 2B (discussed below).

[0034] Additionally or alternatively, the first power source 110 may include one or more solar panels 112 configured to power the propulsion system 104. For example, the one or more solar panels 112 may be located on an upper surface 114 of at least one wing 108 to facilitate sunlight exposure during flight and may be used to charge the propulsion batteries 148. In the illustrated embodiment, the upper surfaces 114 of both the forward and aft wings 108 include solar panels 112. However, other numbers and locations of solar panels 112 are contemplated.

[0035] Additionally or alternatively, first power source 110 may include an internal combustion engine and generator combination (sometimes referred to as a generator set (not shown)) or a fuel cell (not shown). For example, the generator set or fuel cell may be located within electronics enclosure 144 and connected to propulsion unit electric motors 208 or configured to charge propulsion batteries 148. The generator set may be geared or non-geared, for example, of the cylinder-piston type or turbomechanical type.

[0036] Additionally or alternatively, air vehicle 100 may include an adapter plug for charging propulsion battery 148 from a ground-based charging station.

[0037] Additional or alternative implementations of first power source 110 are contemplated.

[0038] Air vehicle 100 also includes traction wheels 118 coupled to frame 102 and configured to engage in tractive engagement with the ground surface during low-speed ground operation of the air vehicle. "Traction engagement with the ground surface" means that friction between the traction wheel outer surface and the ground surface is sufficient to move the air vehicle during powered rotation of the traction wheels along the ground surface during low-speed ground operation. "Low-speed ground operation" occurs while the air vehicle is operating over the ground at a speed between zero and the traction loss speed, at which the lift generated by the moving air vehicle counteracts the weight of the air vehicle to the extent that frictional forces between the traction wheel outer surface and the ground surface no longer generate traction. In some embodiments, the traction loss speed may be 20 miles per hour (mph) or greater. Further, in some such embodiments, the traction loss speed may be 28 miles per hour (mph) or greater. However, other traction loss speeds are contemplated.

[0039] The air vehicle 100 may also include a second power source 116 coupled to the frame 102 and configured to power the traction wheels 118. For example, during takeoff of the air vehicle 100, the traction wheels are driven by the second power source 116 to accelerate the air vehicle from zero speed, through a relatively low speed range where the propulsion system 104 is inoperable or ineffective (e.g., due to a stall condition of the propulsion device 106, implemented as a fixed-pitch propeller 156), to a speed where the propulsion system 104 is effective for powering the air vehicle. In other words, in the non-limiting case of an air vehicle 100 having a fixed-pitch propeller 156, tractive engagement of the traction wheels 118 with the ground surface allows the air vehicle to accelerate to a speed where the fixed-pitch propeller 156 no longer stalls, and the propulsion system 104 can then contribute to the air vehicle 100 reaching or continuing flight speed. Because the propulsion system 104 does not need to accelerate the air vehicle 100 during low-speed ground operation, the propulsion system 104 may be tuned to operate more efficiently at cruising speeds.

[0040] For example, the pitch of the fixed-pitch propeller 156 may be selected for improved efficiency at cruise speed. In another example, the chemical design of the propulsion battery 148 may be selected to provide a high specific energy that increases the cruise range of the air vehicle 100. In another example, the chemical design of the propulsion battery 148 may be selected to provide a high specific energy that reduces weight and improves takeoff performance. As a non-limiting example, while conventional fixed-pitch propellers used for both takeoff and cruise generally have a pitch in the range of 10 to 12 inches, the propulsion system 106 of the present disclosure may be implemented as a fixed-pitch propeller 156 with a pitch of at least 15 inches to improve cruise performance because takeoff thrust is provided or augmented by the thrust wheels 118. In some embodiments, the propulsion system 106 of the present disclosure implemented as a fixed-pitch propeller 156 with a pitch of approximately 18 inches is particularly advantageous for cruise performance.

[0041] Furthermore, compared to conventional air vehicles that require propulsion systems to power all phases of takeoff and cruise, the air vehicle 100 of the present disclosure allows takeoff from much shorter runways. For example, the traction wheels enable the air vehicle to accelerate to 20 mph in a much shorter runway distance than a fixed-pitch propulsion system tuned to operate at both speeds below 20 mph and at cruise speed. Furthermore, the air vehicle 100 of the present disclosure achieves these benefits without the weight, operating cost, or complexity penalties associated with controllable pitch propellers.

[0042] In some embodiments, the second power source 116 may include a pedal set 120 coupled to the frame 102 and configured for operation by a human operator 134 on board the air vehicle 100 that drives the traction wheels 118. In other words, the human operator 134 may pedal the pedal set 120 to directly power the traction wheels 118. For example, vigorous human pedaling may generate a power level of approximately 400 watts.

[0043] Additionally or alternatively, the second power source 116 may include a traction motor 122 configured to drive the traction wheel 118, similar to an electric bicycle. In the illustrated embodiment, the traction motor 122 is mounted directly to the traction wheel 118. However, other mounting arrangements for the traction motor 122 are contemplated. By way of non-limiting example, the traction motor 122 may be implemented as a mid-drive electric motor arrangement (not shown), for example, located below the operator seat 136, and may include a chain and gear arrangement (not shown) to facilitate speed adjustment. In some embodiments, the traction motor 122 is implemented as a 500-watt traction motor. It has been determined that embodiments of the air vehicle 100 of the present disclosure can achieve takeoff speed with approximately 250 watts of power applied to the traction wheel 118 from a human operator 134 vigorously pedaling the pedal set 120, combined with power provided by the 500-watt traction motor 122, even with zero thrust contribution from the propulsion system 104. However, other sizes of traction motor 122 are contemplated. For example, a traction motor 122 implemented as a 750 watt motor may reduce reliance on pedaling without incurring excessive added weight. In some embodiments, ground operation at speeds up to 28 miles per hour may be more efficient using traction motor 122 compared to air vehicles without traction wheels, while benefiting from reduced overall vehicle weight due, for example, to a corresponding reduction in wingspan.

[0044] It should be noted that while the air vehicle 100 can achieve takeoff speed without thrust contribution from the propulsion system 104 in at least some conditions, even with a fixed-pitch propeller 156 optimized for cruise speed, the propulsion system 104 may be used to contribute takeoff thrust in some cases.

[0045] In some embodiments, the second power source 116 may include one or more traction batteries 152 configured to power the traction motors 122. For example, the one or more traction batteries 152 may be housed in an electronics enclosure 144 mounted to the frame 102 forward of the longitudinal dimension L of the traction wheels 118. However, other locations or mounting arrangements are contemplated. Alternatively, the one or more traction batteries 152 may be implemented as traction capacitors. For example, the traction capacitors may discharge during the takeoff phase of the air vehicle 100 to power the traction motors 122. Other methods for powering the traction motors 122 are also contemplated.

[0046] In some embodiments, both the traction battery 152 and the propulsion battery 148 can have a chemistry that prioritizes a high mass-specific energy, improving the range of the air vehicle 100 for both ground operation, where the air vehicle 100 can function as an electric bicycle using the traction battery, and for flight operation. Alternatively, the traction battery 152 can have a chemistry that prioritizes a high mass-specific power (reducing reliance on the propulsion system 104 during takeoff), while the propulsion battery 148 can have a chemistry that prioritizes a mass-specific energy, maximizing cruise range. Alternatively, both the traction battery 152 and the propulsion battery 148 can have a chemistry that prioritizes a high mass-specific power, prioritizing ultra-short takeoff and landing (super-STOL) capability. Alternatively, for applications where the air vehicle 100 is used primarily for short “hop” flights and extended ground operation, the traction battery 152 can have a chemistry that prioritizes a high mass-specific energy, while the propulsion battery 148 can have a chemistry that prioritizes a mass-specific power. Other trade-offs between competing demands that emphasize specific power versus specific energy in either or both of the energy sources of first power source 110 and second power source 116 are also possible. In each alternative, the designs of traction motor 122, propulsion electric motor 208, traction motor ESC 204 (described in more detail below), and propulsion ESC 206 (described in more detail below) may be selected to match the corresponding battery chemistry.

[0047] The air vehicle 100 may further include a guidance wheel 128 pivotally coupled to the frame 102 and configured to steer the air vehicle 100 during ground operation. More specifically, the guidance wheel 128 may be pivoted about an axis 154 extending at least partially along the vertical dimension V, thereby altering the ground path of the air vehicle 100 during ground operation. For example, the air vehicle 100 may include at least one manual control 132 configured to manually orient the guidance wheel in response to manual manipulation by an onboard human operator 134. The manual control 132 may be coupled to the guidance wheel 128 via a suitable manual control linkage 138 that translates movement of the manual control unit 132 into pivoting of the guidance wheel 128. For example, the manual control 132 may be implemented similarly to a push bar used to steer the rear wheel of a recumbent bicycle.

[0048] In the illustrated embodiment, the air vehicle 100 includes first and second guidance wheels 128 aft of the traction wheel 118, positioned on opposite sides of the frame 102 with respect to the span dimension S. Each of the first and second guidance wheels 128 is coupled to a corresponding manual control 132. Thus, the traction wheel 118 and the first and second guidance wheels 128 cooperate to enable the air vehicle 100 to operate as a ground-based cycle on the Earth's surface. In some embodiments, the two rear guidance wheels 128, the corresponding manual control 132 and manual control linkage 138, the seat 136, and the portion of the frame 102 connecting them may be advantageously implemented by incorporating a recumbent bicycle into the air vehicle 100 and swapping out the front wheel of the recumbent bicycle for the traction wheel 118 including the traction motor 122 mounted thereon. Other arrangements and implementations of the one or more guidance wheels 128 are also contemplated.

[0049] The air vehicle 100 may also include a guidance wheel fairing 130 coupled to the frame 102 and at least partially surrounding the guidance wheel 128. In some embodiments, the guidance wheel fairing 130 may be configured to pivot about an axis 154 and operable as a control surface for the air vehicle 100. For example, the guidance wheel fairing 130 may define an airfoil profile having a local airfoil span extending at least partially in the vertical dimension V, causing the guidance wheel fairing 130 to act as a vertical control surface. It should be noted that an axis 154 "extending at least partially in the vertical dimension V" includes an axis 154 oriented obliquely to the plane defined by the vertical dimension V and the span dimension S. In other words, two diagonally oriented guide wheel fairings 130 may cooperate to define a V-shaped control surface that provides vertical and horizontal control surfaces.

[0050] In some embodiments, the same manual controller 132 that enables manual orientation of the guidance wheel 128 to steer the air vehicle 100 during low-speed ground operations can also enable manual orientation of the guidance wheel fairing 130 to set the orientation of the air vehicle 100 during flight. For example, each guidance wheel fairing 130 can be configured to pivot with its corresponding guidance wheel 128, and at least one manual controller 132 configured to orient the guidance wheel 128 to steer the air vehicle during low-speed ground operations can be manually operated to change the orientation of the air vehicle 100 during flight. In other words, the manual controller 132 can be used to pivot the guidance wheel fairing 130 (together with the guidance wheel 128 at least partially enclosed therein) about an axis 154 extending at least partially in the vertical dimension V, such that airflow around the pivoted guidance wheel fairing 130 causes the air vehicle to yaw and change the orientation of the air vehicle 100. Without being limited to a separately implemented manual controller, other mechanisms for pivoting the guidance wheel fairing 130 are also contemplated. For example, independent control of guidance wheel fairing 130 relative to guidance wheel 128 may be utilized to allow pivoting of guidance wheel fairing 130 in a drag-inducing position for use as a speed brake for deceleration at a LZ, while guidance wheel 128 itself remains in a straight orientation for maneuvering air vehicle 100 at the LZ. Alternatively, guidance wheel fairing 130 may be configured to lock in place during ground operations while allowing guidance wheel 128 to pivot internally.

[0051] In embodiments in which more than one guidance wheel 128 is used, the air vehicle 100 may include a respective guidance wheel fairing 130 that at least partially surrounds a corresponding one of the guidance wheels 128 and is configured to pivot therewith. For example, when the first and second guidance wheels 128 are located on opposite sides of the frame 102 with respect to the span dimension S, each guidance wheel fairing 130 may operate as a control surface. The use of the guidance wheel fairings 130 may enable stability, guidance, and control of the air vehicle 100 to be achieved even when the air vehicle 100 does not include vertical control surfaces that are actuable separately from the first and second guidance wheel fairings 130, as shown.

[0052] In some embodiments, the guidance wheel fairing 130 may be pivotable about the axis 154 independent of the pivoting ability (or lack thereof) of the guidance wheel 128. For example, the orientation of the guidance wheel 128 about the axis 154 may even be fixed (i.e., non-pivotable) relative to the frame 102, and the manual controller 132 may be configured to pivot the guidance wheel fairing 130 about the axis 154 while the guidance wheel 128 remains fixed. Other implementations of pivoting each guidance wheel fairing 130 relative to either or both the frame 102 and the corresponding guidance wheel 128 are also contemplated.

[0053] Alternatively, the guidance wheel fairing 130 may be fixed (i.e., non-pivotable) relative to the frame 102 and sized to accommodate pivoting of the enclosed guidance wheel 128 within the airfoil shape of the guidance wheel fairing 130. In any of the above embodiments or otherwise, the guidance fairing 130 may include an independently actuable control flap (not shown) at its aft portion to provide additional controllability.

[0054] In some embodiments, the first and second guidance wheel fairings 130 are further operable to induce drag to slow the air vehicle 100 to a controlled glide path during descent from flight to the ground. The guidance wheel fairings 130 may be pivotable independently of one another, for example, to allow for deployment in opposite directions that create symmetric drag. For example, the first and second guidance wheel fairings 130 can be pivoted outward in opposite directions about axis 154 90 degrees from the position shown in FIG. 1A , inducing significant drag and thereby presenting an obstacle to the airflow that reduces airspeed. While 90 degrees is used as an example, drag-inducing pivots of less than 90 degrees are also contemplated. While axis 154 is illustrated as extending substantially along vertical direction V, a significant amount of drag can be created for orientations of axis 154 that extend only partially vertically. Additionally, the first and second guidance wheel fairings 130 may be further operable in a similar manner to decelerate the air vehicle 100 after landing from flight, i.e., on the ground after landing. Thus, the guidance wheel fairings 130 may advantageously facilitate reducing the length of the ground path required to land the air vehicle 100.

[0055] Notably, the benefits of using the guidance wheel fairing 130 as a control or drag-inducing surface may also be obtained in embodiments that do not include powered traction wheels 118. For example, rather than the traction wheels 118 described herein, the air vehicle 100 may instead include a simple nose wheel and benefit from the guidance wheel fairing 130 described herein. The present disclosure contemplates such use of the guidance wheel fairing 130 independent of the traction wheels 118.

[0056] The guidance wheel fairing 130 can also increase steering traction during ground operation of the air vehicle 100. For example, when a human operator 134 pivots the guidance wheel 128 to perform a right turn, the aerodynamic force of the guidance wheel fairing 130 creates a yaw force that pulls the air vehicle 100 toward the desired right turn.

[0057] In some embodiments, the traction wheels 118 are further configured to provide braking force to the air vehicle 100 during landing, which can advantageously facilitate reducing the length of the ground path required to land the air vehicle 100. Additionally, the traction motors 122 may be further configured for regenerative charging. In response to brake application, or more generally, deceleration of the air vehicle 100 on the landing path, the traction motors 122 may switch to a regenerative mode in which the motors reverse their spin and become generators that convert momentum into electricity. The electricity may be used, for example, to recharge the traction battery 152 (or traction capacitor) or one or more propulsion batteries 148. Embodiments in which braking or regenerative charging is provided by one or more guidance wheels 128 are also contemplated.

[0058] 1C, the air vehicle 100 can also include an airframe 164 coupled to the frame 102 and contoured to define an aerodynamic profile of the air vehicle 100 along the longitudinal dimension L. For example, the airframe 164 can enclose one or more of the human operator 134, the seat 136, the pedal set 120, the manual controls 132, and some or all elements of the frame 102 to reduce drag that would be induced by the less aerodynamic contour of these elements.

[0059] 2A shows a schematic block diagram of an exemplary embodiment of a power system 200 of air vehicle 100. Power system 200 includes, for example, one or more solar panels 112, a pedal set 120, a traction motor 122, one or more propulsion batteries 148, and a traction battery 152 (or traction capacitor).

[0060] Power system 200 may also include a traction motor electronic speed control (ESC) 204 coupled between traction battery 152 and traction motor 122. For example, traction motor ESC 204 may be housed with or integrated into traction motor 122. Additional or alternative power system components associated with traction motor 122 are also contemplated.

[0061] The power system 200 may further include a propulsion unit ESC 206 and a propulsion unit electric motor 208 coupled between each propulsion unit 106 and one or more propulsion batteries 148. For example, the propulsion unit ESC 206 and the propulsion unit electric motor 208 may be housed in a nacelle 140 corresponding to the propulsion unit 106. Additional or alternative power system components associated with the propulsion units 106 are also contemplated.

[0062] Power system 200 may also include a propulsion system power bus 212 that couples solar panels 112 to propulsion batteries 148 and enables solar panels 112 to charge propulsion batteries 148. Power system 200 may further include a solar panel converter 210 that converts direct current (DC) voltage provided by solar panels 112 to DC voltage for propulsion batteries 148. Other implementations of propulsion system power bus 212 are also contemplated.

[0063] In some embodiments, power system 200 may include a traction wheel power bus link 218 that couples a second power source 116 associated with traction wheels 118 (e.g., one or more of traction battery 152, traction motor 122, or pedal set 120) to propulsion system power bus 212. In this arrangement, second power source 116 may be used to charge power for first power source 110 (e.g., propulsion battery 148), or vice versa. Power system 200 may further include a traction wheel converter 220 that converts a direct current (DC) voltage provided by second power source 116 to a DC voltage output by solar panel 112 (which enables traction wheel power bus link 218 to be connected via solar panel converter 210) or to the DC voltage of propulsion system power bus 212 for direct coupling. The power system 200 may also include a bus power monitor 214 and an avionics package 216 configured to automatically implement and control cross-charging between the first power source 110 and the second power source 116.

[0064] 2B is a schematic block diagram of another exemplary embodiment of a power system 200 for air vehicle 100. Power system 200 shown in FIG. 2B may include the same or similar elements as those described above, except that propulsion batteries 148, designated here as 148F, for the left and right inboard motors of both the forward and aft wings 108 may be housed in the airframe rather than in the nacelles 140 of the propulsion units 106. Other arrangements of propulsion batteries 148 and other components of power system 200 are also contemplated.

[0065] Additionally, the power system 200 may include a USB port 222 to allow charging of the on-board human operator's 134 cell phone 224 and, optionally, connectivity with other interfaces. Other types of ports are contemplated.

[0066] 3 is a table 300 of example control features corresponding to each degree of freedom of the air vehicle 100. The control features may include the guidance wheel fairing 130, as described above, operable by a human operator 134 to adjust the orientation of the air vehicle 100. The control features may also include a throttle (not shown) operable by an on-board human operator 134 to adjust altitude during flight by adjusting motor speed across all propulsion units 106, represented in Table 3 as "Differential RPM All Motors," and a pedal set 120 and traction motor 122 to adjust the speed of the air vehicle 100 during ground operations, takeoff, and landing.

[0067] Control features may also include varying speed control inputs to the propulsion ESCs 206 of the distributed propulsion systems 106 that control the movement of the air vehicle 100 in a particular degree of freedom. In particular embodiments, the avionics package 216 includes a controller 202 configured to autopilot the air vehicle 100 within a particular degree of freedom using differential speed control inputs to the propulsion ESCs 206 while accommodating manual control of some aspects of flight by an onboard human operator 134. For example, the controller 202 may be programmed to automatically maintain the air vehicle 100 in level flight during the cruise phase while accommodating altitude adjustments by the human operator 134 using the throttle.

[0068] More specifically, the controller 202 may be programmed to automatically maintain the current altitude by automatically varying the speeds of all propulsion unit electric motors 208 to increase or decrease the lift of the air vehicle 100 in response to altitude perturbations. The controller 202 may also be programmed to detect a human operator's 134 desire to increase or decrease altitude by detecting manual adjustments to the throttle, and in response, shift control of the motor speeds to prevent a rapid increase or decrease in altitude. The controller may also revert to altitude autopilot in response to detecting that the throttle remains at a set point. The controller may also be programmed to detect a human operator's 134 desire to decrease altitude (e.g., to initiate landing or to change the desired grind path for landing) by detecting that the manual control 132 is being used to deploy the guidance wheel fairing 130 to a drag-inducing position, and in response, shift control of the motor speeds to prevent a rapid decrease in altitude during descent. In other words, the controller can shift to limited autopilot control that accommodates the manual control actions of the human operator 134 while maintaining the air vehicle 100 within a safe envelope of dynamic stability.

[0069] Additionally or alternatively, the controller 202 may be programmed to perform pitch control using two or more of the multiple propulsors 106 distributed along the vertical dimension V of the air vehicle. More specifically, the controller may automatically reduce pitch perturbations by commanding differential thrust from two or more propulsors 106 distributed along the vertical direction. For example, in the illustrated embodiment, the rear wings 108 are positioned above the forward wings 108 by a height H along the vertical dimension V, and the controller may vary the motor speeds of the four propulsors 106 on the forward wings relative to the motor speeds of the four propulsors 106 on the rear wings to control the pitch orientation of the air vehicle 100.

[0070] Additionally or alternatively, the controller 202 may be programmed to implement yaw control using two or more of the multiple propulsors 106 distributed along the span dimension S of the air vehicle. More specifically, the controller can automatically reduce yaw perturbations by commanding differential thrust from two or more propulsors 106 distributed along the span dimension. For example, in the illustrated embodiment, the four propulsors of each wing 108 are distributed along the wing's span, and the controller can vary the motor speed of the propulsor 106 on the right side of the wing relative to the motor speed of the propulsor 106 on the left side of the wing to control the yaw orientation of the air vehicle 100. The controller may also be programmed to detect the human operator's 134 desire to change orientation, for example, by sensing when the manual control device 132 is being used to deploy the guidance wheel fairing 130 into a yaw-inducing position, and in response, can shift control of the motor speed to prevent abrupt changes in yaw while the guidance wheel fairing 130 is so deployed. In response to the manual control device 132 returning to a non-yaw-inducing position, the controller 202 can detect that the desired new orientation has been established and can shift back to automatic control of the yaw perturbation. In other words, the controller can shift to limited autopilot control that accommodates the manual control actions of the human operator 134 while maintaining the air vehicle 100 within a safe envelope of dynamic stability.

[0071] Additionally or alternatively, the controller 202 may be programmed to implement roll control using two or more of the multiple propulsion units 106 located at outboard positions on opposite sides of the frame 102 along the span dimension S. More specifically, the controller may automatically reduce roll perturbations by commanding differential thrust from two or more propulsion units 106 located at opposite outboard positions. For example, in the illustrated embodiment, the controller may control the pitch orientation of the air vehicle 100 by varying the motor speed of the left outboard propulsion unit 106 on each of the forward and aft wings relative to the motor speed of the right outboard propulsion unit 106 on each of the forward and aft wings (this variation creates differential lift on the left wing tip relative to the right wing tip).

[0072] In some embodiments, control flaps 126 may also be used to control the dynamic orientation of air vehicle 100. For example, the position commands for each control flap 126 may be provided either manually by a human operator 134, automatically by an autopilot function of controller 202, or a combination thereof.

[0073] Additionally, as noted in the "Land" column of table 300, controller 202 may also be programmed to assist in maintaining the stability of air vehicle 100 during ground operations while adapting to human operator inputs to throttle and manual control 132. As previously mentioned, during ground operations, manual control 132 may control the orientation of air vehicle 100 by steering guidance wheel 128.

[0074] Other implementations for controlling air vehicle 100 in one or more degrees of freedom are also contemplated.

[0075] 4 illustrates an example embodiment of a controller data flow 400 that may be used by the controller 202. The controller data flow 400 may receive motor speed commands 402 corresponding to each propulsion unit ESC 206, including commands for eight propulsion units 106 distributed along the forward and aft wings 108 in the illustrated example, provided by the throttle, by the autopilot function of the controller 202, or a combination thereof. The controller data flow 400 may also receive aft flap commands 404 and forward flap commands 406 corresponding to the positions of the aft and forward control flaps 126, provided by the human operator 134, by the autopilot function of the controller 202, or a combination thereof. The controller data flow 400 may further receive right guidance wheel fairing commands 408 and left guidance wheel fairing commands 410 provided by the human operator 134. These commands may be sent to an aero-propulsive model 418, which calculates the resulting forces and moments on the air vehicle 100 during flight. Forces and moments from the aerodynamic propulsion model 418 may be sent to the air vehicle model 422 .

[0076] Controller data flow 400 may also include an environmental model 416 that models the effects of atmospheric conditions (e.g., crosswinds) on air vehicle 100. The output of environmental model 416 may be sent to aerodynamic and propulsion model 418 for inclusion in aerodynamic force and moment calculations, or may be sent directly to air vehicle model 422.

[0077] Controller data flow 400 can also receive traction motor speed commands 412 and pedal speed commands 414 provided by human operator 134. These commands can be sent to traction motor model 420, which calculates the resulting forces and moments on air vehicle 100 during ground operation. The output of traction motor model 420 can be sent to air vehicle model 422.

[0078] The air vehicle model 422 can calculate model state outputs 424, including the position, orientation, and their rates of change of the air vehicle 100, based on various environmental, force, and moment inputs, and state visualization outputs 426 for displaying the state to the human operator 134. The autopilot function of the controller 202 can use the model state outputs 424 to generate one or more next iterations of the motor rate commands 402, the aft flap commands 404, or the forward flap commands 406.

[0079] FIG. 5 illustrates an exemplary computing device that may be used in connection with any of the systems or components of controller 202, avionics package 216, traction motor ESC 204, propulsion ESC 206, or other components disclosed herein. In this example, FIG. 5 illustrates a computing system 500 including components that communicate electrically with each other using a system connection 502, such as a bus. Computing system 500 includes a processing unit (CPU or processor) 504 and a system connection 502 that couples various system components to processor 504, including system memory 508, such as read-only memory (ROM) 510 and random access memory (RAM) 512. Computing system 500 may include a cache 506 of high-speed memory directly connected to processor 504, closely connected to processor 504, or integrated as part of processor 504. Computing system 500 can copy data from memory 508 and / or storage device 514 to cache 506 for quick access by processor 504. In this way, cache 506 can provide a performance boost that avoids processor delays while waiting for data. These and other modules may control or be configured to control processor 504 to perform various operations. Other system memory 508 may also be available for use. Memory 508 may include multiple different types of memory with different performance characteristics. Processor 504 may include any general-purpose processor; hardware or software services, such as services 1-516, services 2-518, and services 3-520 stored in storage device 514, configured to control processor 504; and special-purpose processors in which software instructions are incorporated into the actual processor design. Processor 504 may also be a fully self-contained computing system, including multiple cores or processors, buses, memory controllers, caches, etc.Multi-core processors can be symmetric or asymmetric.

[0080] To enable user interaction with the computing system 500, the input device(s) 526 can represent any number of input mechanisms, such as a microphone for speech, a touch-sensitive screen for gesture or graphical input, a keyboard, a mouse, motion input, speech, etc. The output device(s) 522 can also be one or more of numerous output mechanisms known to those skilled in the art. In some examples, a multimodal system can allow a user to provide multiple types of input for communicating with the computing system 500. The communications interface 524 can generally manage and control user input and system output, including wireless input and output links. There is no limitation to operation with a particular hardware arrangement, and therefore the basic functionality herein can be easily replaced as improved hardware or firmware arrangements are developed.

[0081] The storage device 514 is a non-volatile memory and may be a hard disk or other type of computer-readable medium capable of storing data that can be accessed by a computer, such as a magnetic cassette, a flash memory card, a solid-state memory device, a digital versatile disk, a cartridge, random access memory (RAM) 512, read-only memory (ROM) 510, and hybrids thereof.

[0082] The storage device 514 may include services 516, 518, 520 for controlling the processor 504. Other hardware or software modules are contemplated. The storage device 514 may be connected to the system connection 502. In one aspect, a hardware module that performs a particular function may include software components stored on a computer-readable medium in association with hardware components necessary to perform the function, such as the processor 504, the system connection 502, and the output device 522.

[0083] In some embodiments, computer-readable storage devices, media, and memories may include cable or wireless signals containing bitstreams, etc. However, when referred to, non-transitory computer-readable storage media explicitly excludes media such as energy, carrier signals, electromagnetic waves, and the signals themselves.

[0084] Methods according to the above-described examples may be implemented using computer-executable instructions stored on or otherwise available from a computer-readable medium. Such instructions may include, for example, instructions and data that cause or otherwise configure a general-purpose computer, a special-purpose computer, or a special-purpose processing device to perform a particular function or group of functions. Some of the computer resources used may be accessible over a network. The computer-executable instructions may be, for example, binaries, intermediate format instructions such as assembly language, firmware, or source code. Examples of computer-readable media that may be used to store instructions, information used, and / or information created during methods according to the described examples include magnetic or optical disks, flash memory, USB devices with non-volatile memory, networked storage devices, etc.

[0085] Apparatuses implementing methods according to these disclosures can include hardware, firmware, and / or software and can take any of a variety of form factors. Typical examples of such form factors include laptops, smartphones, small form factor personal computers, personal digital assistants, rack-mounted devices, standalone devices, etc. The functionality described herein can also be embodied in peripheral devices or add-in cards. Such functionality can be implemented on a circuit board, among different chips or different processes running on a single device, to name a few.

[0086] The instructions, media for communicating such instructions, computing resources for executing them, and other structures for supporting such computing resources are means for providing the functionality described in these disclosures.

[0087] While various examples and other information have been used to describe aspects within the scope of the appended claims, those skilled in the art will be able to derive a wide variety of implementations using these examples, and no limitation of the claims based on the specific features or arrangements in such examples should be implied. Moreover, while some subject matter may be described in terms specific to example structural features and / or method steps, it should be understood that the subject matter defined in the appended claims is not necessarily limited to these described features or acts. For example, such functionality may be distributed differently or performed in components other than those identified herein. Rather, the described features and steps are disclosed as example components of systems and methods within the scope of the appended claims.

[0088] Claim language containing "at least one of" means at least one of a set, and indicates that one member of the set or multiple members of the set satisfy the claim. For example, claim language containing "at least one of A and B" means A, B, or A and B.

Claims

1. An air vehicle, The frame and a propulsion system coupled to the frame; a first power source coupled to the frame and configured to power the propulsion system; a traction wheel coupled to the frame and configured to engage a ground surface during low speed ground operation of the air vehicle; a second power source coupled to the frame and configured to power the traction wheels; An aircraft equipped with:

2. 10. The air vehicle of claim 1, wherein the air vehicle weighs less than 254 pounds, has a fuel capacity not exceeding 5 U.S. gallons, and is incapable of level flight at speeds exceeding 55 knots.

3. The air vehicle of claim 1 , wherein the propulsion system includes one or more fixed-pitch propellers.

4. The second power source is 10. The air vehicle of claim 1, including a pedal set coupled to the frame and configured for operation by a human operator on board the air vehicle that drives the traction wheels.

5. The second power source is The air vehicle of claim 1 , including a traction motor configured to drive the traction wheel.

6. 6. The air vehicle of claim 5, wherein the first power source includes one or more propulsion batteries, and the traction motor is operable to charge the one or more propulsion batteries.

7. The air vehicle of claim 5 , wherein the second power source includes one or more traction batteries or traction capacitors configured to power the traction motors.

8. The air vehicle of claim 1 , wherein the low speed ground operation includes a speed of the air vehicle between zero and 28 miles per hour.

9. The air vehicle of claim 1 , wherein the first power source includes one or more propulsion batteries and solar panels.

10. further comprising at least one wing coupled to the frame; The air vehicle of claim 1 , wherein the propulsion system includes a plurality of electrically powered propulsion units distributed along the at least one wing.

11. 11. The air vehicle of claim 10, wherein the at least one wing includes a forward wing and an aft wing, the first set of the plurality of propulsion devices is distributed along the forward wing and the second set of the plurality of propulsion devices is distributed along the aft wing, and a width of the air vehicle does not exceed 12 feet.

12. The air vehicle of claim 10 , wherein the first power source includes a plurality of propulsion batteries distributed along the at least one wing.

13. The air vehicle of claim 10 , wherein the first power source includes one or more solar panels located on an upper surface of the at least one wing.

14. The air vehicle of claim 1 , wherein the traction wheels are configured to apply a braking force to the air vehicle during landing of the air vehicle.

15. a guidance wheel pivotally coupled to the frame and configured to steer the air vehicle during ground operation; a guidance wheel fairing coupled to the frame, at least partially surrounding the guidance wheel, and configured to pivot with the guidance wheel; Furthermore, The air vehicle of claim 1 , wherein the guidance wheel fairing is operable as a control surface for the air vehicle.

16. the guidance wheel includes a first guidance wheel, and the guidance wheel fairing includes a first guidance wheel fairing; The flying vehicle is a second guidance wheel pivotally coupled to the frame and configured to steer the air vehicle during ground operation; a second guidance wheel fairing coupled to the frame, at least partially surrounding the second guidance wheel and configured to pivot with the guidance wheel; Furthermore, 16. The air vehicle of claim 15, wherein the first guidance wheel and the second guidance wheel are located on opposite sides of the frame.

17. 17. The air vehicle of claim 16, wherein the traction wheel and the first and second guidance wheels cooperate to enable the air vehicle to operate as a ground-based cycle on the surface of the Earth.

18. An air vehicle, The frame and a propulsion system coupled to the frame; a first power source coupled to the frame and configured to power the propulsion system; a guidance wheel pivotally coupled to the frame and configured to steer the air vehicle during ground operation; a guidance wheel fairing coupled to the frame, at least partially surrounding the guidance wheel, and configured to pivot with the guidance wheel; Equipped with The guidance wheel fairing is operable as a control surface of the air vehicle.

19. 20. The air vehicle of claim 18, wherein the guidance wheel fairing defines an airfoil profile.

20. 20. The air vehicle of claim 18, wherein the guidance wheel fairing includes an independently actuable control flap at its aft portion.

21. the guidance wheel includes a first guidance wheel, and the guidance wheel fairing includes a first guidance wheel fairing; The flying vehicle is a second guidance wheel pivotally coupled to the frame and configured to steer the air vehicle during ground operation; a second guidance wheel fairing coupled to the frame, at least partially surrounding the second guidance wheel and configured to pivot with the guidance wheel; Furthermore, 20. The air vehicle of claim 18, wherein the first guidance wheel and the second guidance wheel are located on opposite sides of the frame.

22. 22. The air vehicle of claim 21, wherein the air vehicle does not include vertical control surfaces that are actuable separately from the first guidance wheel fairing and the second guidance wheel fairing.

23. 22. The air vehicle of claim 21, wherein the first guidance wheel fairing and the second guidance wheel fairing are further operable to induce drag to decelerate the air vehicle to a controlled glide path during descent from flight to the ground.

24. 22. The air vehicle of claim 21, wherein the first guidance wheel fairing and the second guidance wheel fairing are configured to lock in place after landing from flight.

25. It also has a front wheel, 22. The air vehicle of claim 21, wherein the first guidance wheel fairing and the second guidance wheel fairing cooperate to enable the air vehicle to operate as a ground-based cycle on the surface of the Earth.

26. 26. The air vehicle of claim 25, wherein the nose wheel comprises a traction wheel configured for tractive engagement with a ground surface during low speed ground operation of the air vehicle.

27. An air vehicle, The frame and a guidance wheel pivotally coupled to the frame; a guidance wheel fairing at least partially surrounding the guidance wheel and configured to pivot; at least one manual control device configured to orient the guidance wheel fairing in response to operation by a human operator on board the air vehicle, the orientation being selectable to set the air vehicle's orientation in flight; a plurality of propulsion units coupled to the frame; a controller coupled to the frame, the controller including at least one processor in communication with a memory and operably coupled to the plurality of propulsion devices, the memory storing instructions executable by the processor to cause the air vehicle to automatically maintain level flight during flight; An aircraft equipped with:

28. 28. The air vehicle of claim 27, wherein two or more propulsors of the plurality of propulsors are distributed along a span dimension of the air vehicle, and the instructions are executable to cause the processor to automatically reduce yaw perturbations about an orientation set by manual orientation by commanding differential thrust from the two or more propulsors.

29. 28. The air vehicle of claim 27, wherein two or more propulsors of the plurality of propulsors are distributed along a span dimension of the air vehicle, and the instructions are executable to cause the processor to automatically reduce pitch perturbations by commanding differential thrust from the two or more propulsors.

30. 28. The air vehicle of claim 27, wherein two or more propulsors of the plurality of propulsors are located outboard along a span dimension on opposite sides of the frame, and the instructions are executable to cause the processor to automatically reduce roll perturbations by commanding differential thrust from the two or more propulsors.

Images