Enhanced flight mode

Abstract

In the descending process of the aircraft, the flight control system seeks and keeps a glide gradient, and the glide gradient is determined according to the parameters input by a single pilot; for example, the position of a control shaft of a flight joystick. During landing approach, a pilot visually observes a predetermined landing site, so that the pilot can easily determine an appropriate guide slope selection. The glide slope defines a ratio of forward and descent speeds that is automatically established and maintained / updated as a function of pilot input, while these speeds are automatically lowered during descent, although the two speed directions are each affected by significantly different aircraft mechanisms controlling them. The aircraft ends its glide path when the speed is zero or near zero so as to be able to land by short-distance vertical descent. Thus, the pilot gets rid of both the problems of coordinating the speed to reach a specific guide gradient and reducing the speed while maintaining such coordination.

Description

[0001] Related Applications

[0002] This application claims priority to U.S. Provisional Patent Application No. 63 / 410,673 filed on September 28, 2022.

[0003] The contents of this reference are incorporated herein by reference in their entirety.

[0004] Technical Field and Background Art

[0005] The present invention, in some embodiments, relates to the field of aircraft flight control, and more particularly, but not limited to, flight control during an aircraft landing process.

[0006] A multirotor helicopter aircraft design uses multiple power source driven propellers to provide vertical lift and / or horizontal thrust. Multirotor helicopters are used and / or proposed for use in a range of applications, including cargo and / or passenger transportation. Practical multirotor helicopters have been made possible by technologies such as computerized control and / or sensor electronics, relatively lightweight and powerful electric motors, improvements in battery storage energy-to-weight ratios, and / or improved power generation using relatively lightweight generators.

[0007] Aircraft are controlled in flight in multiple directional axes (e.g., yaw, pitch, and roll). They have a forward speed and a rate of climb (ROC, which is negative when descending, or "descent rate"). Overall control of these flight parameters is usually achieved by using several independently operating aircraft mechanisms. Often, more than one flight mechanism affects a particular flight parameter, and a particular flight mechanism often affects more than one flight parameter. Summary of the invention

[0008] According to an aspect of some embodiments of the present disclosure, there is provided a method for automatically controlling a forward speed and a descent speed of an aircraft during its descent to a landing site, the method comprising: adjusting a target glide slope of the aircraft according to an updated indication by a pilot of a correction to the target glide slope of the aircraft; automatically adjusting a speed ratio as the target glide slope is adjusted to correspond to the descent of the aircraft along the target glide slope; and maintaining the speed ratio corresponding to the target glide slope while automatically reducing the forward speed from a start speed to a stop speed; wherein the start speed and the stop speed differ by at least half of the start speed of the aircraft.

[0009] According to some embodiments of the present disclosure, the termination speed is less than 10% of the startup speed of the aircraft.

[0010] According to some embodiments of the present disclosure, the termination speed is stationary.

[0011] According to some embodiments of the present disclosure, the start-up speed is at least 80% of a design cruising speed of the aircraft.

[0012] According to some embodiments of the present disclosure, the terminal speed is reached when the aircraft is above the landing site.

[0013] According to some embodiments of the present disclosure, the aircraft descends from a start altitude to a termination altitude while slowing down from the start speed to the termination speed, and a ratio of the start altitude to the termination altitude is within three times a ratio of the start speed to the termination speed.

[0014] According to some embodiments of the present disclosure, within at least half of the difference between the starting altitude and the ending altitude, the forward speed decreases nearly linearly as a function of altitude.

[0015] According to some embodiments of the present disclosure, the deceleration of the forward speed as a function of altitude comprises a deceleration that increases within at least 10% of a difference between the starting altitude and the ending altitude.

[0016] According to some embodiments of the present disclosure, the deceleration of the forward speed as a function of altitude comprises a deceleration that decreases within at least 10% of a difference between the starting altitude and the ending altitude.

[0017] According to some embodiments of the present disclosure, within at least 90% of the difference between the starting altitude and the ending altitude, the forward speed decreases linearly on average as a function of altitude.

[0018] According to some embodiments of the present disclosure, the termination height is within 2 meters from the landing site in the vertical direction.

[0019] According to some embodiments of the present disclosure, the termination height is within 0.5 meters from the landing site in the vertical direction.

[0020] According to some embodiments of the present disclosure, the termination velocity is less than 2 m / s.

[0021] According to some embodiments of the present disclosure, the termination speed is stationary.

[0022] According to some embodiments of the present disclosure, the termination altitude and the termination speed are reached at a position above the landing site.

[0023] According to some embodiments of the present disclosure, the method includes hovering the aircraft at the position above the landing site.

[0024] According to some embodiments of the present disclosure, the time process of the update indication of the correction includes: a first stage, in which the correction results in a modification of the target glide slope until the course of the aircraft descending along the target glide slope is aimed at the landing place; and a second stage, which is after the first stage, in which the correction keeps the course of the aircraft aimed at the landing place and keeps descending along the target glide slope.

[0025] According to some embodiments of the present disclosure, the time process of the update indication of the correction includes: a first stage, in which the correction causes a modification of the target glide slope until the route of the aircraft descending along the target glide slope is aimed at a position away from the landing site; and a second stage, in which the correction adjusts the route of the aircraft toward the landing site along the adjustment value of the target glide slope.

[0026] According to some embodiments of the present disclosure, the pilot communicates the updated indication of the correction by adjusting an axis of a flight controller.

[0027] According to some embodiments of the present disclosure, the method includes, when the terminal speed is reached: stopping adjusting the ratio of the speeds to correspond to a descent of the aircraft along the target glide slope; and using the axis of the flight controller as an indication of a target flight parameter other than the glide slope.

[0028] According to some embodiments of the present disclosure, the target flight parameters include movement of the aircraft along only one vertical height direction and a direction orthogonal to the vertical height.

[0029] According to some embodiments of the present disclosure, after reaching the terminal speed, the aircraft remains airborne, but the altitude of the aircraft is no longer adjusted according to the updated indication of the correction to the target glide slope.

[0030] According to some embodiments of the present disclosure, maintaining the ratio corresponds to the target glide slope so that the aircraft moves along a glide path, and the movement along the glide path includes a forward descending movement along a straight line, during which the target glide slope remains unchanged and the lateral movement of the aircraft remains constant.

[0031] According to some embodiments of the present disclosure, the updated indication of the correction and the subsequent maintaining of the ratio of the speed generate a glide path corresponding to the target glide slope, and the glide path guides the flight path of the aircraft toward a ground position closer to or farther away from the aircraft according to the target glide slope indicated by the correction, which is steeper or gentler.

[0032] According to some embodiments of the present disclosure, the revised update indication and the subsequent maintaining of the ratio of the speeds generate a glide path corresponding to the target glide slope, the glide path descending toward the landing site at a relatively higher speed to achieve a relatively steeper target glide slope, and the same forward speed.

[0033] According to some embodiments of the present disclosure, the updated indication of the correction is determined by the pilot based on the pilot's direct view of the position of the landing site at an angle of 10° or more descending from the horizontal plane.

[0034] According to some embodiments of the present disclosure, the updated indication of the correction is determined by the pilot based on the pilot's direct view of the position of the landing site at an angle of 30° or more below the horizontal.

[0035] According to some embodiments of the present disclosure, the pilot's direct view of the position of the landing site is performed through a window portion located in the aircraft below the pilot's waist level.

[0036] According to some embodiments of the present disclosure, the pilot's direct view of the position of the landing site is through a window portion, which is positioned adjacent to the pilot's footrests from the pilot's perspective.

[0037] According to some embodiments of the present disclosure, the updated indication of the correction is determined by the pilot based on a camera view of the landing site at an angle of 30° or more below the horizontal.

[0038] According to one aspect of some embodiments of the present disclosure, there is provided a flight control system for a vertical landing aircraft, comprising a processor and a memory comprising instructions, wherein the instructions instruct the processor to: adjust the target glide slope of the aircraft according to an updated indication by a pilot to correct the target glide slope of the aircraft; adjust the ratio of forward speed to descent speed as the target glide slope is adjusted to correspond to the descent of the aircraft along the target glide slope; and maintain the ratio corresponding to the target glide slope while automatically reducing the forward speed from a starting speed to a termination speed; wherein the starting speed and the termination speed differ by at least half of the starting speed.

[0039] According to some embodiments of the present disclosure, the flight control system includes the aircraft.

[0040] According to some embodiments of the present disclosure, the terminal speed is stationary, and the starting speed is at least 80% of a design cruising speed of the aircraft.

[0041] According to some embodiments of the present disclosure, the aircraft descends from a start altitude to a termination altitude while slowing down from the start speed to the termination speed, and a ratio of the start altitude to the termination altitude is within three times a ratio of the start speed to the termination speed.

[0042] According to some embodiments of the present disclosure, the termination altitude and the termination speed are reached at a position above the landing site, and the flight control system maintains the aircraft in a hovering state at the position.

[0043] According to an aspect of some embodiments of the present disclosure, there is provided a method for a pilot to land an aircraft, comprising: looking out from the aircraft in a downward direction through a forward window adjacent to a foot pedal of the pilot's feet; identifying a visible landing site in the downward direction through the forward window; and approaching the landing site while reducing speed and altitude until the aircraft lands at the landing site at a stationary forward speed.

[0044] According to some embodiments of the present disclosure, the approach is performed while maintaining a forward speed and a descent speed proportional to each other, the proportion establishing a glide slope that guides the aircraft to the touchdown site.

[0045] According to some embodiments of the present disclosure, the approach is performed while reducing forward speed using a function of decreasing vertical distance from the touchdown site.

[0046] According to an aspect of some embodiments of the present disclosure, there is provided an aircraft, comprising: a window in a front lower position, which includes an area located below the waist of a pilot in an upright sitting position during forward level flight of the aircraft; and a light positioned to project one or more target indications into the pilot's field of view using the window as a reflective surface.

[0047] According to an aspect of some embodiments of the present disclosure, a method for flying an aircraft is provided, comprising: providing a first sequence of flight direction indications to the aircraft using movement of a flight controller along an axis, wherein the first sequence of flight direction indication controls a glide slope setting for determining a glide path of the aircraft; and providing a second sequence of flight direction indications to the aircraft using movement of the flight controller along the same axis, wherein the second sequence of flight direction indication controls one of a group consisting of: horizontal but non-vertical movement of the aircraft, vertical but non-horizontal movement of the aircraft, and a pitch angle of the aircraft, but not horizontal or vertical movement of the aircraft.

[0048] According to an aspect of some embodiments of the present disclosure, there is provided a vertical landing aircraft having a computerized flight control system that provides an enhanced flight mode for the aircraft, wherein the computerized flight control system maintains a fixed ratio between the forward speed and the vertical speed of the aircraft while causing both speeds to decrease toward a stationary landing speed as a function of height above ground.

[0049] According to some embodiments of the present disclosure, the aircraft includes a transparent window, which faces downward toward the ground from the perspective of a pilot of the aircraft who is sitting upright, and through which the landing area reached when reaching a stationary speed can be seen during descent and speed reduction.

[0050] According to some embodiments of the present disclosure, the aircraft includes a camera facing downward toward the ground; and a display screen that displays a view to the pilot of the aircraft in which the landing area reached when reaching a stationary speed is seen during the descent and speed reduction process.

[0051] According to an aspect of some embodiments of the present disclosure, there is provided a computerized flight control system configured to maintain a fixed ratio between a forward speed and a vertical speed of an aircraft while causing both speeds to decrease toward a stationary landing speed as a function of altitude above the ground.

[0052] According to some embodiments of the present disclosure, the stationary landing speed is achieved in the hover mode when zero forward speed is reached close to zero altitude.

[0053] According to some embodiments of the present disclosure, the fixed ratio selects the location of the target landing area, and the fixed ratio is selected based on the adjustment of the control stick movement.

[0054] According to some embodiments of the present disclosure, the target landing area is adjusted by changing the descent angle in response to the control stick movement, the changing comprising replacing the fixed ratio with a ratio corresponding to the changed descent angle.

[0055] According to some embodiments of the present disclosure, the flight control system adjusts the target landing area by changing the descent rate and / or forward speed deceleration in response to the replaced fixed ratio.

[0056] According to an aspect of some embodiments of the present disclosure, there is provided a method for vertically landing an aircraft, comprising automatically maintaining a fixed ratio between a forward speed and a vertical speed of the aircraft while decreasing both speeds toward a stationary landing speed as a function of height above the ground.

[0057] Unless otherwise defined, all technical and / or scientific terms used herein have the same meanings as those generally understood by those skilled in the art in relation to the present disclosure. Although methods and materials similar or equivalent to the methods and materials described herein may be used to practice or test embodiments of the present disclosure, exemplary methods and / or materials are described below. In the event of a conflict, the patent specification including the definitions shall prevail. In addition, the materials, methods, and examples are for illustrative purposes only and are not meant to be necessarily restrictive.

[0058] As will be appreciated by those skilled in the art, various aspects of the present disclosure may be embodied as a system, method or computer program product. Therefore, various aspects of the present disclosure may take the form of an embodiment that is entirely hardware, an embodiment that is entirely software (including firmware, resident software, microcode, etc.), or an embodiment that combines software and hardware aspects, all of which may generally be referred to herein as a "circuit," "module," or "system" (e.g., a method that can be implemented using a "computer circuit"). In addition, some embodiments of the present disclosure may take the form of a computer program product embodied in one or more computer-readable media having a computer-readable program code thereon. The implementation of the method and / or system of some embodiments of the present disclosure may involve performing and / or completing selected tasks manually, automatically, or in combination with both. In addition, according to the actual instruments and devices of some embodiments of the method and / or system of the present disclosure, a number of selected tasks may be performed by hardware, software or firmware and / or a combination thereof (e.g., using an operating system).

[0059] For example, the hardware for performing selected tasks according to some embodiments of the present disclosure can be implemented as a chip or circuit. As software, the selected tasks according to some embodiments of the present disclosure can be implemented as multiple software instructions, which are executed by a computer using any suitable operating system. In some embodiments of the present disclosure, one or more tasks performed in the method and / or system are performed by a data processor (also referred to herein as a "digital processor", referring to a data processor that runs using a group of digital bits), such as a computing platform for executing multiple instructions. For example, the instruction execution element of the processor may include one or more microprocessor chips, ASICs and / or FPGAs. Optionally, the data processor includes a volatile memory and / or non-volatile storage for storing instructions and / or data, such as a magnetic hard disk and / or a removable medium, which is used to store instructions and / or data. Optionally, a network connection is also provided. Optionally, a display screen and / or a user input device, such as a keyboard or a mouse, are also provided. Any of these embodiments mentioned in this article is more commonly used as an example of a computer circuit.

[0060] In some embodiments of the present disclosure, any combination of one or more computer-readable media may be used. A computer-readable medium may be a computer-readable signal medium or a computer-readable storage medium. A computer-readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared or semiconductor system, device or apparatus, or any suitable combination of the former. More specific examples (non-exhaustive list) of computer-readable storage media include the following: an electrical connection with one or more wires, a portable computer floppy disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above devices. In this article, a computer-readable storage medium may be any tangible medium that can contain or store a program for use or connection with an instruction execution system, device or device. A computer-readable storage medium may also contain or store information for use by such a program, for example, data structured in a manner recorded in a computer-readable storage medium so that a computer program can access these data in the form of, for example, one or more tables, lists, arrays, data trees and / or other data structures. Here, computer-readable storage media that record data in the form of retrievable digital bit groups are also referred to as digital memories. It should be understood that in some embodiments, when the computer-readable storage medium is not read-only in nature and / or is in a read-only state, the computer-readable storage medium can also be optionally used as a computer-writable storage medium.

[0061] Herein, a data processor is said to be "configured to" perform data processing operations because it is connected to a computer-readable medium to receive instructions and / or data therein, process them, and / or store the results of the processing in the same or another computer-readable medium. The processing performed (optionally processing the data) is specified by the instructions, and the effect is that the processor operates in accordance with the instructions. The processing behavior can be optionally or alternatively represented by one or more other terms; for example: compare, estimate, determine, calculate, identify, associate, store, analyze, select and / or convert. For example, in some embodiments, the digital processor receives instructions and data from a digital memory, processes the data according to the instructions, and / or stores the results of the processing in the digital memory. In some embodiments, "providing" the processing results includes one or more of the acts of transmitting, storing and / or displaying the processing results. The display optionally includes displaying on a display screen, providing the results by sound indication, printout or other forms accessible to human sensory capabilities.

[0062] A computer readable signal medium may include a propagated data signal containing computer readable program code, for example, in baseband form or as part of a carrier wave. Such a propagated signal may take any of a variety of forms, including but not limited to electromagnetic, optical, or any suitable combination thereof. A computer readable signal medium may be any computer readable medium that is not a computer readable storage medium, which may communicate, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device.

[0063] Program code embodied on a computer readable medium and / or data used thereby may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, RF, etc., or any suitable combination of the foregoing.

[0064] The computer program code for performing the operation of some embodiments of the present disclosure can be written in any combination of one or more programming languages, including object-oriented programming languages, such as Java, Smalltalk, C++ or similar languages, and traditional procedural programming languages, such as "C" programming languages ​​or similar programming languages. In addition or alternatively, a sequence of logical operations (optionally logical operations corresponding to computer instructions) can be embedded in the design of ASIC and / or the configuration of FPGA devices. The program code can be executed completely on the user's computer, or it can be executed partially on the user's computer (for example, as an independent software package), and it can also be executed partially on the user's computer and partially on a remote computer, or it can be executed completely on a remote computer or server. In the latter scenario, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or an external computer can be connected (for example, through the Internet of an Internet service provider).

[0065] Some embodiments of the present disclosure are described below with reference to the flowchart representations and / or block diagrams of the methods, devices (systems) and computer program products of the embodiments of the present disclosure. It is understood that each box in the flowchart representation and / or block diagram and the combination of multiple boxes in the flowchart representation and / or block diagram can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate a means for implementing the functions / actions specified in one or more boxes in the flowchart and / or block diagram.

[0066] These computer program instructions may also be stored in a computer-readable medium, which may instruct a computer, other programmable data processing apparatus, or other device to operate in a specific manner, so that the instructions stored in the computer-readable medium produce a product, which includes instructions for implementing the functions / actions specified in one or more boxes in the flowchart and / or block diagram.

[0067] The computer program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device, so that a series of operating steps are executed on the computer, other programmable apparatus, or other device to produce a computer-implemented process, so that the instructions executed on the computer or other programmable apparatus provide a process for implementing the functions / actions specified in one or more boxes in the flowchart and / or block diagram.

[0068] Some of the methods described herein are generally designed for computer use only and may not be feasible or practical for a human expert to perform manually. A human expert who wants to perform a similar task manually, such as inspecting an object, may wish to use an entirely different approach, such as leveraging expert knowledge and / or the pattern recognition capabilities of the human brain, which may be much more efficient than manually completing the steps of the method described herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0069] Some embodiments of the present disclosure are described herein with reference to the accompanying drawings only by way of example. Now with specific reference to the details in the accompanying drawings, it should be emphasized that the details shown are exemplary and are intended to provide an illustrative discussion of the embodiments of the present disclosure. In this regard, the description combined with the accompanying drawings will make it obvious to those skilled in the art how the embodiments of the present disclosure can be implemented.

[0070] In the attached picture:

[0071] Figure 1Schematically illustrating, according to some embodiments of the present disclosure, automatically controlling a relative rate of claim (ROC) and forward speed to maintain a glide slope during a landing approach of a vertical landing vehicle in terrain to a target landing site;

[0072] Figure 2A Schematically illustrates the range of elevation angles that can be used to directly visually select a landing site according to some embodiments of the present disclosure;

[0073] Figure 2B Schematically illustrates the relationship between horizontal velocity (forward velocity) and vertical velocity (descent velocity) to obtain the glide slope constant k according to some embodiments of the present disclosure;

[0074] Figure 2C Schematically illustrates direct joystick adjustment of the glide slope constant k from the perspective of a cockpit of an aircraft according to some embodiments of the present disclosure;

[0075] Figure 2D According to some embodiments of the present disclosure, the forward speed v H 、ROCv V , the equations relating the aircraft altitude h (altitude above the landing area), the glide slope constant k, and the velocity function f(h);

[0076] Figure 3A The relationship between the ground speed and the altitude of a vertical landing aircraft during a landing approach is schematically illustrated according to some embodiments of the present disclosure;

[0077] Figure 3B The relationship between the descent speed (negative ROC) and the altitude of a vertical landing aircraft during a landing approach is schematically illustrated according to some embodiments of the present disclosure;

[0078] Figure 4A – 4E schematically illustrates multiple stages of a landing approach for a vertical landing vehicle according to some embodiments of the present disclosure;

[0079] Figure 5 is a schematic flow chart of a method for controlling a landing approach of a vertical landing aircraft according to some embodiments of the present disclosure; and

[0080] Figure 6 A flight control system for a vertical landing aircraft according to some embodiments of the present disclosure is schematically illustrated. DETAILED DESCRIPTION

[0081] The present invention, in some embodiments, relates to the field of aircraft flight control, and more particularly, but not limited to, flight control of an aircraft during landing.

[0082] Overview

[0083] Landing Control

[0084] Broad aspects of some embodiments of the present disclosure relate to flight landing guidance systems and methods.Under typical aircraft control schemes, the requirements for manual coordination are high to simultaneously control the descent rate relative to the ground height, forward speed, approach direction, and destination during the approach of a vertical landing aircraft.

[0085] To land at a controlled airport, existing systems typically require the selection of a geographic location from a list or map, and then appropriate adjustments to the map and / or aircraft controls to execute the landing itself, e.g., along a runway and / or on a landing pad, typically based on a protocol of handoff requests and authorities. Controlled airport landings are particularly well suited for automation because airport conditions are actively monitored and maintained to facilitate safe operation of the aircraft.

[0086] However, in other scenarios, the landing site may be chosen more or less autonomously, and / or the chosen landing site may be unknown and / or variable. This may be particularly true for the landing site of a sport aircraft. Short / vertical takeoff or landing (SVTOL) aircraft are able to choose a landing site particularly flexibly. For example: going for a picnic at a location on a mountain seen from the air, which involves the use of landing skills and methods that are different from those of a controlled airport. Such an aircraft may be, for example, a helicopter or a multirotor aircraft.

[0087] One possible method of landing on a site is to operate indirectly by setting parameters of an automatic and / or auto-assisted landing system from a map. Based on the previous example, a mountain is found on an electronic map (e.g., relative to the current location), and the navigation system indicates that this is the landing destination. However, this creates a layer of indirection between visual site identification and landing site identification because the map location may be identified incorrectly; and / or the map itself may be incomplete, out of date, and / or otherwise incorrect. In addition, even if the location of the landing site is correctly identified, the landing site may not be sufficiently characterized to enable reliable automatic landing. There may be temporary obstacles (e.g., livestock) and / or permanent obstacles (e.g., fences, boulders, cables, and / or trees) that are unknown to the navigation system and / or not detected by the autoland system.

[0088] Therefore, setting up a general automatic system (e.g., a navigation map system accessed by a portable device relying on GPS signals) to navigate to a landing site may involve potential dangers: there are risks when selecting a point on the map to land (e.g., a mistake may be made when reading the map, or the map may not be updated and have new obstacles that were not there before (e.g., a sheep standing on a hill that was not shown in the map).

[0089] Thus, for safety, the pilot preferably approaches the landing site in a manner that verifies the suitability and safety of the landing site and its surroundings while maintaining margin to identify and maneuver around obstacles and conditions that could interfere with landing and / or endanger the aircraft. The risk naturally increases near the ground. The ground is home to a variety of potential irregularities, with a large number of them to collide with - and the time to react decreases as the ground is closer. Therefore, the potential advantage lies in safely and gradually reducing both altitude and speed on approach while also maintaining visual contact with the landing site. For example, the pilot can visually control while looking out from the aircraft at the target landing site.

[0090] However, an aircraft has multiple control degrees of freedom: for example, the positions of control surfaces and / or power levels for different engines. Also, control operations may affect the aircraft in complex ways that often affect more than one aspect of flight dynamics: for example, both speed and pitch angle may be affected simultaneously; and the same given pilot input may have different effects depending on the aircraft's current dynamic state (e.g., hovering vs. fast forward flight) and / or the current environment (e.g., turbulence and / or crosswind). This may increase the complexity of efficiently reaching a target landing site without overshoot, provided that the aircraft is in a safe dynamic state (e.g., not too fast, or not approaching or exceeding safe limits of performance, responsiveness, and / or pilot perception and / or reaction time).

[0091] Pilot-selected glide slope

[0092] An aspect of some embodiments of the present disclosure relates to a system and method for flight landing, which promotes the aircraft glide slope to an input parameter directly controlled by the pilot. In some embodiments, the glide slope is mapped to the positioning of the primary flight control device (primary pilot control apparatus), for example, preferably the control axis of the flight joystick (flight controller). In some embodiments, the axis for controlling the glide slope can be switched between multiple functions according to the flight mode during flight. For example, it can also be used as an altitude control (e.g., during cruise flight) and / or as a forward / backward position control (e.g., for slight adjustments in position above the landing site when hovering).

[0093] Herein, an "axis" of a flight stick / flight controller refers to a control axis that provides an output that is variable within a range of other states between extremes, e.g., the range includes at least a center state of the range, and a plurality of distinguishable states on each side of the center value. For example, a typical digital control axis may output an integer value within an 8-bit (0–255) or 16-bit (0–65535) range, optionally truncated on one or both sides of the range, or with a dead band. The use of non-digital control axes (e.g., based on resistance and / or voltage levels) is not excluded. The pilot may perceive the control axis to be numerically continuous between its extreme values. The control axis is not necessarily implemented as a flight stick axis; for example, it may be implemented as a slider. It is not excluded that the pilot input is implemented by means other than a control axis; for example, a toggle switch or a push button arrangement, the grade change and / or the rate of grade change commanded by it is proportional to the duration and / or number of presses.

[0094] The mapping between the pilot input and the indication of the (target) glide slope is optionally performed by any suitable process and / or means. In a simple example, the mapping may be a lookup table that indexes the raw control axis value to the glide slope. However, the flight computer 651 may maintain an internal representation of the target glide slope that is relatively set and / or adjusted depending on the operation of the pilot input device.

[0095] Thus, in some embodiments, an enhanced flight mode is provided for a vertical landing aircraft, helicopter, or multirotor aircraft, wherein a computerized flight control system (e.g., Figure 6 The flight control system 650 in FIG. 6 maintains a fixed ratio between forward speed and vertical speed while decreasing both speeds as a function of altitude above the ground. The ratio is fixed by the current glide slope, which is selected and optionally changed by the pilot during the approach to landing. References to forward speed herein are understood to be forward ground speed (i.e., speed relative to the surface of the earth).

[0096] The corresponding method of using the enhanced flight mode produces a linear glide slope that makes it easy for the pilot to estimate the exact location of the landing during the approach and eliminates the workload associated with reducing the approach speed to achieve the landing while maintaining the glide slope. This capability is particularly useful for landing at a location without a controlled approach, and optionally also for descending to a landing location with a controlled approach, for example, based on landing guidance equipment provided by the runway and / or instructions from an air traffic controller.

[0097] Direct (optionally and preferably single-axis) pilot control of the glide slope can reduce pilot control complexity by eliminating the need to coordinate management of forward speed and descent rate (through separate operation of the aircraft subsystems they each control). In order to maintain the pilot-selected glide slope, the horizontal aircraft speed (forward speed) and the vertical aircraft speed (descent rate) are automatically adjusted to maintain a ratio that is appropriate for the currently selected glide slope (e.g., the tangent of its angle). For example, at a glide slope with an inclination of 45°, the rate of forward speed and the descent rate are the same. At a glide slope with an inclination of 10°, the forward speed is approximately 5.8 times the descent rate. Optionally, the landing glide path can be started from any initial speed reached by the aircraft. The initial speed when starting the glide slope control mode is typically at least 80% of the aircraft's design cruise speed (which can, for example, be in the range of 80–120 knots, such as 90 knots, without excluding other values). Alternatively, the glide path may begin at any initial forward speed or descent speed (absolute, or relative to its designed cruise speed) of the aircraft (e.g., subject to the constraints of the aircraft's performance). The forward speed at which the pilot begins providing direct glide slope input during descent is also referred to herein as the "start-up speed" (of the aircraft).

[0098] It is important to note that definitions of forward speeds other than forward ground speed (e.g., forward airspeed) generally lack the properties to place the visually pinpointed target landing site at the end of the glide slope. However, forward airspeed measurements may be corrected to forward ground speed as appropriate. Optionally, the difference may be ignored (e.g., at high altitude / speed) even if this is expected to result in a bias, thereby requiring the pilot to continue to make corrections to the input, particularly as the relative contribution of wind speed bias increases as forward speed decreases.

[0099] Alternatively, the landing glide path may be started from any initial altitude reached by the aircraft. For example, the initial altitude at which the glide path is started may be, for example, in the range of 100–2000 m, or other suitable circumstances, for example, depending on the characteristics of the aircraft and / or the flight plan, such as cruising altitude. For example, starting from 2000 m, a 10° glide slope has a distance to the landing site of approximately 11.5 km; a 60° glide slope has a distance to the landing site of approximately 0.5 km. Glide slopes starting from other altitudes are adjusted proportionally.

[0100] The altitude at which the pilot begins providing direct glide slope inputs (beginning glide slope control mode) during a descent is also referred to herein as the "start altitude."

[0101] In an idealized scenario: once the glide path is aligned with the landing site, the aircraft can descend along a constant glide slope at varying speeds (e.g., as a function of altitude above the ground) to the landing site. For example, during the approach, the speed can be reduced to a stationary speed as a function of altitude above the ground, so the aircraft will enter a stationary hover above or just before the landing site. Starting from a stationary speed (preferably zero), a (vertical or near-vertical) landing operation can be initiated. Other functions of altitude and / or other parameters will be explained below. In some embodiments, initiating a vertical landing operation includes leaving a glide slope control mode. This can include remapping a pilot control previously used as a glide slope indication to a different function; for example, controlling altitude, or forward / reverse positioning above the landing site.

[0102] Since the glide slope is controlled by the pilot (and therefore can be modified), it is not necessarily maintained constant throughout the landing approach. Alternatively, it is modified during any portion of the landing approach. Preferably, the glide slope is updated and modified throughout the landing approach as long as the glide slope control mode remains active. "Update and modify" means that the system repeatedly accesses the state of an indication of the pilot control, such as the flight controller axis position, and uses this indication to adjust (e.g., calculate) the current target glide slope of the aircraft.

[0103] During the approach, the pilot can use controls to adjust the glide slope in an intuitive manner - where the controls actually move the touchdown point by steepening and flattening the glide slope, changing the heading and / or moving the entire glide slope sideways (optionally, without changing the heading).

[0104] For example, the pilot may initially select an incorrect glide slope, and / or the glide slope at the beginning of the landing approach mode may not be suitable for the intended landing site. The pilot may change the landing site, and / or as the approximate area of ​​the landing site approaches and it can be more clearly observed, the landing site can be selected more accurately (and optionally progressively). At higher speeds (for example, to slow down the increase in cabin air pressure, and / or to be able to maintain a safe high speed in a longer flight distance), it may not be desirable to fully reduce the glide slope to the "average" glide slope required for landing to preferably establish a more rapid descent after the aircraft slows down. On the contrary, the pilot may prefer a steep and high-speed initial descent phase, for example, in order to observe (or simply experience) the terrain more carefully. Control and / or sensing inaccuracies may cause drift, inducing the pilot to modify the glide slope, for example, ground speed sensing and / or wind correction is inaccurate. Any of these changes may be naturally compensated when the pilot provides input to guide the aircraft back to the visually selected landing site.

[0105] Pilot observing landing site

[0106] Other aspects of controlling to maintain a suitable glide path may be intuitively experienced by the pilot, and / or suitable for automatic control and minimize risk, particularly with an appropriate airframe design. For example, in some embodiments, the system automatically approaches the landing site in an intuitive manner while maintaining control by the pilot.

[0107] "Appropriate airframe design", in some embodiments, includes a design that allows the pilot to see directly through the terrain at low elevation angles. For example, an "approach flight mode" (glide slope control mode) can be used for assisted landing maneuvers with glide slopes of 10° to 60° below the horizon. The slope angle is also determined by the pilot's visibility of the target landing area. The pilot sees the visibility of the final landing site below through a window under his / her legs (or through a camera pointed at the landing site) to trigger and start the glide slope approach mode. The glide path is a straight line all the way to a very low altitude hover. Since the glide path may be changed by the pilot, the actual flight path may be curved.

[0108] Note that the typical glide slope for a fixed-wing aircraft on final approach to a runway is much shallower than this, ranging from 3°–5.5° (the latter being considered quite steep).

[0109] In some embodiments, an aircraft configured to allow for a steeper glide slope provides a viewing window that is substantially located below the pilot's feet; for example, a window that is at least partially obscured from the pilot's perspective by the pilot's legs and / or feet.

[0110] The angle of declination that can be observed is optionally adjusted by adjusting the pitch angle of the aircraft. Optionally (e.g., when the aircraft is a multirotor aircraft), the pilot can adjust this angle coupled with the aircraft pitch angle adjustment to the glide slope and / or descent speed. For example, different combinations of aircraft pitch angle and thruster power can achieve the same glide slope. In some embodiments, this is compounded with the wing-body lift effect related to speed and angle of attack.

[0111] Changes in speed may impose constraints on the aircraft pitch angle, for example, as the aircraft slows down near the ground to avoid generating excessive forward (horizontal) speed, it may be constrained to fly more horizontally. In some embodiments, the glide slope is partially constrained by the aircraft pitch angle, for example, optionally constrained to those angles consistent with keeping the landing site in view. This constraint is optionally applied more strictly when closer to the ground, because this is where the greatest certainty is needed. Therefore, the pilot can choose an initial (steep) slow glide speed that will deliberately undershoot the selected landing site to have a gentler glide slope (and better landing site visibility) during landing.

[0112] As long as the pilot can observe the terrain at the end point of the current glide slope, it should be intuitively obvious to them where on the ground this is simply by observing drift and / or optical flow patterns in the field of view (e.g., without the aid of a map or even automatic markings provided by the aircraft). Ideally, the current ground target will increase in size, but this current ground target will "stay still" during the approach from the pilot's perspective (where it can be anywhere). Everything else visually flows outward from this point.

[0113] In non-ideal situations (for example, if there is drift in the glide path, perhaps due to lateral movement of the aircraft), then adjusting the glide slope will adjust the pilot's "vertical" (up / down, also near / far) perception axis to directly correct this drift, while drift along the "horizontal" perception axis (left-right) can be corrected by adjusting one or both of the aircraft angle (azimuth) and the aircraft's lateral speed.

[0114] Visually viewing the touchdown site means that the pilot can operate the controls to ensure that they remain at a fixed angular position relative to (among other things) the pilot's viewing angle. Optionally, keeping the touchdown area at a fixed position relative to the pilot's eyes (e.g., between his legs) is key to making this glide slope descent easy for the pilot to achieve: the pilot is flying along a predetermined straight line, toward a selected (and monitored) point in the lower window. Even if the instantaneous flight path differs significantly from the pilot's perceived direction of motion, incremental corrections made by the pilot to stabilize the relative direction of the touchdown site are usually sufficient to maintain the glide path, provided that the speed is sufficiently reduced on closer approach.

[0115] Landing site indication and / or selection based on glide slope

[0116] However, in some embodiments, a display is provided that shows the navigation computer's estimated landing site location (e.g., based on where the ground will be intersected based on the current trajectory including the glide slope). This may be marked on a map display, for example, as an area and / or location, and / or as light reflected from a transparency placed in the pilot's measured and / or estimated line of sight so that (for the pilot) it corresponds to the estimated angular position of the landing site. In some embodiments, the display includes a "foot-down" reflective display, for example, a beam of directional illumination that is scattered / reflected on the surface of a transparent viewport located at the pilot's line of sight below the pilot's waist.

[0117] Optionally, the navigation system is configured to determine potential landing sites within the approximate area toward which the aircraft is heading (e.g., an area deemed to be large enough and sufficiently flat based on known map information) and to appropriately indicate to the pilot those landing sites (or their absence, optionally including an indication that they are "prohibited" for reasons other than physical suitability).

[0118] Optionally, the aircraft and the pilot interact at least in part through flight navigation selection to select a specific landing site (e.g., when several landing sites may still be available). For example, a single location that is closest (or otherwise "most suitable," such as in terms of size and / or flatness) to the currently selected glide path is highlighted, which can be accepted by the pilot by pressing a button or other indication (e.g., verbal confirmation). Optionally, multiple options that are substantially consistent with the current glide path are displayed, and the pilot is able to select from them (e.g., verbally state one, and / or poll and select). The landing can then proceed, and the pilot is free to operate the aircraft as otherwise (e.g., including by directly selecting a glide slope), with the landing site selected at that location displayed to help maintain flight direction and / or as a basis for providing warnings. Optionally, the pilot instructs the navigation system to convert the glide slope-assisted landing site selection into instructions for at least a partially automatic landing procedure (e.g., fly along the glide slope to hover over the landing site, adjusting as needed to reach the landing site). The pilot can optionally take over as desired (eg, again using the axis controls to select a glide slope).

[0119] Optionally, once the target landing site is selected, the navigation computer and / or the pilot and the navigation computer working in conjunction may employ a more indirect navigation strategy to reach the landing site. For example, the pilot may optionally deviate from the direct glide path to the landing site, while the navigation computer informs the pilot in real time whether the final correction to prevent overshoot is still within the flight envelope of the aircraft. Optionally, the computer calculates the parameters of the optimal path to the selected landing site (e.g., optimal in terms of energy budget, optionally within limiting performance parameters, such as descent rate and / or aircraft pitch angle), indicates these parameters to the pilot (e.g., including a suggested target glide slope, which may be dynamic during descent, and the computer will adjust the speed appropriately along this target glide slope), and / or guides the aircraft itself according to these parameters. In some embodiments, feedback to the pilot includes force feedback (e.g., on the flight controller) that is proportional to the deviation between the course indication provided by the pilot and the selected glide slope.

[0120] speed as a function of height

[0121] As another aspect of the glide path: the aircraft speed is automatically reduced, in some embodiments, as a function of the descent altitude.

[0122] In a conventional aircraft, the final descent may be a straight line, but the forward speed is roughly constant, so a constant rate of descent, to maintain the straight line. The difficult part for a human pilot is to maintain the straight line while reducing speed (all the way to zero for a vertical landing aircraft), so the rate of descent (ROC - rate of climb) needs to be constantly adjusted. Reducing speed and ROC simultaneously requires a highly coordinated effort and involves changing both power and pitch angle, which also affect each other.

[0123] During the glide slope control mode or "approach mode", according to some embodiments of the present disclosure, the aircraft remains on that line (as long as the pilot still selects that line) while reducing speed along that line (by automatically coordinating both power and pitch angle), and creating a situation where the fore and aft movement of the control stick only changes the angle of the approach line. To the pilot, it appears that the control stick moves the aiming / target point on the ground. In some embodiments, the speed along the linear descent path is reduced linearly. For example, the pilot starts with a "default" glide slope and ends at some target or aiming point on the ground that the aircraft is flying to. The pilot only needs to adjust the position of this point on the ground with the flight control stick. In addition to selecting the glide slope, the pilot can also change the course longitudinally: for example, by changing the bearing and / or moving the aircraft with a lateral component.

[0124] Automatic (and ensured) deceleration may thereby reduce the risk of ground obstacles, while also allowing the pilot more time to react to ground observations and / or aircraft behavior. In any case, the final reduction of the forward (ground) speed to a stationary speed slow enough to initiate the final landing (e.g., zero, imperceptible, less than 10 cm / sec, or less than 1 m / sec) is expected to occur at / above the landing site (or at least at a location surveyed by the pilot as a suitable landing space). The reduction of the descent rate to a stationary state (e.g., a brief hover at a fixed altitude, or the descent is slowed to a low rate, e.g., 0–100 cm / sec, before landing) optionally occurs at or above the ground clearance. Preferably, the altitude will be sufficient to ensure that contact with the ground is broken (the altitude is optionally determined based on the possibility of unknown ground obstacles), but not too high to avoid prolonged hovering time as the aircraft descends. In some embodiments, the target altitude at the minimum descent speed is a few centimeters (e.g., 10-100 cm); the target altitude is optionally increased to account for wind conditions, objects / irregularities at the landing site, and / or uncertainty in any of these factors. The altitude at which the aircraft exits the glide slope control mode is also referred to herein as the "termination altitude." Optionally, the termination altitude is within 0.1 m, 0.5 m, 1 m, or 2 m of the landing site in the vertical direction.

[0125] Here, the forward speed of the aircraft when the glide slope control mode is terminated is also referred to as the "termination speed". In some embodiments, the termination speed is no greater than half of the aircraft's start-up speed, however, when the termination speed is not less than this value, it is expected that the aircraft will not be in a state suitable for vertical landing without further action. In some embodiments, the termination speed is less than 10% of the aircraft's start-up speed. In some embodiments, the termination speed is less than 2 m / sec, less than 1 m / sec, or less than 0.1 m / sec. Preferably, the termination speed is a stationary speed (e.g., zero, or stationary in the sense of "allowing station-keeping" by the pilot's action).

[0126] Prior to reaching the touchdown site, the altitude used is measured relative to, for example, the ground currently beneath the aircraft, relative to the altitude above the ground at the intersection of the current extrapolated glide path and the ground surface, relative to the altitude above the ground at a selected GPS coordinate, and / or relative to a pilot-entered and / or pilot-adjusted (e.g., offset) altitude. In some embodiments, speed adjustments as a function of altitude are made relative to a static altitude above the ground reference. Optionally, the altitude above the ground reference is dynamic, but is static as long as a particular projected course of flight is maintained. Optionally, the altitude above the ground reference is variable along the projected course of flight. Optionally, the altitude above the ground reference is constrained to change relatively slowly (e.g., to avoid causing sudden speed adjustments). The altitude above the ground reference can be switched along the glide path as needed, for example, according to any of these definitions, as they may change, become available, and / or increase in relation to the aircraft's navigation.

[0127] Optionally, the maximum altitude in some area of ​​the terrain is used as a ground clearance reference. Optionally, the ground clearance reference is determined from the terrain in another way; for example, excluding peaks that the assumed route is to avoid. The area of ​​the terrain used to determine the ground clearance reference is optionally selected and / or sized based on the current route. For example, it can be selected to include the expected end point of the current route. The area of ​​the area can increase when the speed is higher and / or in response to more aggressive manipulation (for example, reflecting uncertainty); conversely, it can be reduced when the speed is reduced and / or the route is maintained more constantly.

[0128] The terrain area considered when calculating the altitude optionally includes the terrain at the aircraft's current position and any expected landing site, and / or the terrain between the aircraft's current position and any expected landing site, for example, at least to prevent collision with the terrain, and optionally also to prevent traversal of intermediate terrain at unacceptably high speeds at low altitudes, such as speeds exceeding 50 knots at an altitude of 20 m or less from the ground and / or known ground obstacles.

[0129] Height-dependent functions and other speed function parameters

[0130] The main constraint of the altitude-dependent velocity function is that the vehicle comes to a standstill as it approaches the intended hovering altitude over the landing site. “Standstill” means at least that the velocity is reduced to the point where the vehicle remains “over” the landing site, allowing a human-supervised landing without backtracking.

[0131] For example, the aircraft is sufficiently stationary that the pilot can perform a position-holding maneuver to maintain the aircraft near the landing site. For example, the pilot can perform multiple decisions and actions, as appropriate, using normal human reaction time, to complete the landing (landing completion) from a location above the landing site to a location on the landing site without leaving the airspace above the landing site; the landing site is optionally considered to include an area with a diameter of approximately two aircraft lengths or less. However, various embodiments are not limited to immediately switching out of the glide slope control mode over the landing site.

[0132] In some embodiments, in at least one of the vertical descent speed and the forward speed, the stationary speed is zero. In some embodiments, the speed does not reach zero completely before landing (e.g., landings with a short roll are not excluded), and even for vertical landings, at least a brief pre-landing hover is typically expected. In some embodiments, once the aircraft is close to the ground and the landing site, the aircraft can thus leave the glide slope control mode, for example, replacing the last selected end point of the glide path with the target ground location and adjusting the speed appropriately to reach the location, whether or not the speed matches the specific glide slope. This may include switching the pilot's control mode, such as using forward / backward left / right up / down pilot commands to directly position the aircraft.

[0133] For at least some glide slopes, the altitude-dependent speed function preferably allows the same fixed ratio of forward airspeed to descent speed to be maintained over all or nearly all (e.g., at least 90%, 95%, or 99% of the time and / or distance) of the range between the initial descent and the minimum (e.g., functional rest and / or zero) forward speed just prior to landing, at which speed ratio the initial descent is achieved as close to full forward cruise speed as possible. For some supported glide slopes, it may not be practical to maintain the target location in clear direct line of sight of the pilot at all times; for example, due to constraints on the pitch angle of the aircraft. A camera view of the landing site is optionally provided at any stage; but particularly for landing, a camera view is optionally provided, for example to verify that the ground directly below the aircraft is clear of obstacles. For some of the glide slopes supported, all or nearly all of the above glide slopes may not be practical at all speeds; for example, a full speed maximum-slope diving descent may be precluded at some speeds for safety and / or aerodynamic reasons, particularly in embodiments providing wing lifting bodies. In some embodiments, for some altitudes / speeds where glide slopes are not available, the aircraft control system optionally transfers pilot inputs to the nearest available glide slope, and / or otherwise warns and / or corrects the pilot.

[0134] In some embodiments, the relationship between altitude and speed is selected as a constraint that is limited by restrictions on what can be maintained and / or recovered in one or both flight directions. For example, the constraints on deceleration are generally different along one axis (forward) than along another axis (descent); and in either case, they are limited. Depending on the aerodynamics of the wing-lifting body, the direction of the aircraft may be constrained at different speeds and speed ratios; for example, such a wing provided in some embodiments may function primarily as a brake at lower speeds, while its lift at higher speeds limits the independence of the through-air direction and the pitch angle of the aircraft. The importance of maintaining the touchdown site in the pilot's forward field of view may be subject to constraints that vary with altitude. These factors may affect which glide slopes are available and / or how aggressively braking maneuvers are performed.

[0135] Under these constraints (and in any other similar circumstances that may apply), the speed along the glide path for a particular glide slope may optionally be selected to decrease (preferably monotonically, and at least on average) as any function of altitude.

[0136] An approximately uniform deceleration is optional (linear reduction to an expected zero or near-zero speed at the touchdown site), but is not required. In some embodiments, the proportional reduction in forward speed (e.g., between the start speed and the end speed) is approximately equal to the proportional reduction in altitude. Optionally, the two proportional reductions are within a factor of 1.25, 2, 3, or 4 of each other. For example, there may be a "gamma" constant γ that exponentially adjusts the relationship between altitude (above the target altitude) and forward speed, e.g. In this case, γ = 1 indicates a linear relationship, and higher / lower values ​​of γ (e.g., in [3 -1 ,3] range indicates an initially slower or initially faster deceleration.

[0137] It is particularly noted that the function of minimizing the time to reach the landing site, and the function of minimizing the energy used to reach the landing site. Constraints may be included to avoid excessive dynamic acceleration at the landing site, for example, to maintain safety and / or comfort. In some embodiments, a function with lower dynamics (slower / more constant deceleration) may be provided; for example, to reduce the need to change the pitch angle of the aircraft, and / or to otherwise prioritize the comfort of passengers and / or the visibility of the landing site to the pilot. In some embodiments, steeper glideslopes are associated with deceleration functions, which are more actively optimized, for example, to save time and / or energy, while gentler glideslopes are biased towards comfort. Optionally, the selection (and optionally the pilot's optional) optimization (or another aspect of other height / speed function "style") is not related to the glideslope. As an example of "style", a pilot (e.g., a pilot familiar with the area) may prefer to swipe down to a lower altitude relatively quickly before a sudden drop in speed and landing; or vice versa (e.g., in order to have time to choose a landing site), a relatively sudden initial deceleration at a high altitude, and then a leisurely descent.

[0138] In some embodiments, time, distance and / or another input is used as a parameter that can be considered as modifying the baseline altitude function that determines the speed. For example, if more flight time has passed after takeoff, or there is a long distance to reach the landing site, energy efficiency can be given more priority. These parameters, as well as altitude, are optionally used as proxies for each other, in whole or in part. Once the landing mode begins, a longer distance can be considered as a proxy for a gentler glide slope, otherwise the altitude is the same. However, landing from a lower altitude generally means a shorter landing time / distance. In short, there is no special requirement that the altitude itself must be used as an independent variable of the function, or even strictly speaking, it is not required to be an independent variable. However, "altitude" is a reference for ease of description because landing gives it a definite final value, and because along the glide slope (or even a monotonically decreasing glide slope), each "altitude" is only visited once relative to this reference. Therefore, the speed mentioned here as a function of altitude should be understood to be equivalently replaced under appropriate circumstances. However, while controlling the glide slope, the pilot still has the ability to perceive the selection of a ground position (eg, along a ground axis) toward which the aircraft is to descend.

[0139] Before explaining at least one embodiment of the present disclosure in detail, it should be understood that the application of the present disclosure is not necessarily limited to the details of the structure and arrangement of the components and / or methods described in the following description and / or drawings. The features described in the present disclosure, including the features of the present invention, may have other embodiments, or be implemented or performed in various different ways.

[0140] Parameters for descent to landing under glide slope control

[0141] Reference now Figure 1 , which schematically illustrates automatic control of a relative rate of compensation (ROC) and forward speed to maintain a glide slope during a landing approach of a vertical landing vehicle 1 to a target landing site 3 in a terrain 2 according to some embodiments of the present disclosure.

[0142] At position 10A, the aircraft 1 is in the descent phase before landing, with a relatively low descent speed 12 relative to the forward speed 13 that determines the descent slope 11. When the aircraft 1 reaches position 10B, the pilot has placed the vertical landing aircraft 1 on the glide slope 4 (slightly steeper than the descent slope 11). The glide slope 4 is maintained at positions 10C, 10D and 10E, while the forward speed 13 and the descent speed 12 are reduced; however, these speeds are maintained at the same ratio to maintain the same glide slope 4 and remain in the target position to reach a position at or just above the target landing site 3.

[0143] Reference now Figure 2A , which schematically illustrates a range of elevation angles that may be used for direct visual selection of a landing site 3 according to some embodiments of the present disclosure. Axis 20 represents the direction of forward flight (horizontally), and axis 21 represents the direction of descent (vertically), establishing a pitch angle plane represented by circle 20A. Typical glide slopes are within range 22, between approximately 10° (glide slope 22B) and 60° (glide slope 22A) below the horizontal plane. The glide path is not necessarily on pitch angle plane 2A as shown, as the aircraft may experience non-zero yaw angles.

[0144] In some embodiments, aircraft 1 includes wings 10 and rotors 5 .

[0145] In some embodiments, the wing 10 is a fixed wing that provides up to at least 25%-75% lift at the forward cruising speed of the aircraft 1. In some embodiments, the wing 10 includes a half that protrudes laterally from either side of the fuselage 6. Optionally, the wing 10 is a fixed shape (e.g., without aerodynamic control surfaces). Other wing configurations (e.g., a wing mounted on a support column, a twin wing, and / or a wing with movable control surfaces) are not excluded.

[0146] A vertical stabilizer 7A is also shown. A split tail arrangement may optionally be used (e.g., including a vertical stabilizer located on either portion of the split tail). One or more horizontal stabilizers may optionally be provided (e.g., as part of the tail and / or in a canard configuration on the front side of the wing 10).

[0147] In some embodiments, thrust is provided by rotors 5. In some embodiments, the plane of rotation 5A of the propeller of each rotor 5 is fixed in direction relative to the fuselage 6 of the aircraft 1. The flight control system of the aircraft optionally adjusts the pitch angle direction of the aircraft 1 (i.e., the angle in the pitch angle plane represented by circle 20A) as part of adjusting the ratio between horizontal thrust and vertical thrust, and / or as part of adjusting the effective total thrust (e.g., the thrust at a fixed rotor speed, which is affected by the relative airspeed at a selected angle of the airflow through the rotor). In addition, the rotor speed, including the relative rotor speed, is adjusted by the flight control system as part of adjusting the ratio between horizontal thrust and vertical thrust, and / or as part of adjusting the effective total thrust. Optionally, one or more control surfaces are provided that can adjust the aerodynamic performance of the aircraft in response to the airflow conditions above the aircraft, and / or these control surfaces can adjust (e.g., transfer) the thrust by diverting the airflow generated by the rotors 5. In some embodiments, four rotors 5 are provided. In some embodiments, the rotors 5 are driven by electricity, i.e., by one or more onboard batteries. In some embodiments of the present disclosure, other configurations of wings, powerplants (eg, different types and / or numbers of engines), and / or power sources are optionally provided.

[0148] In some embodiments, the cockpit 7 of the aircraft 1 is configured as a high-visibility cockpit, and the transparent area on any lateral side thereof is located at or below the waist of the pilot sitting in the cockpit to ensure good lateral visibility of the ground. In some embodiments, the front lower window 8 provides an observation area located at or below the pilot's waist, such as Figure 2C 7. Optionally or alternatively, ground visual monitoring is provided by a camera 9, such as an internally or externally mounted camera. Optionally, the aircraft 1 carries one or more passengers in addition to the pilot (e.g., a passenger sitting next to the pilot). For example, the aircraft's load capacity is optionally 150 kg or more, 200 kg or more, 250 kg or more, 350 kg or more, or 500 kg or more. In some embodiments, the aircraft's load capacity is in the range of 150-350 kg, or 100-400 kg.

[0149] It is important to note that, particularly in the area of ​​"short range" (e.g., 120 km or less range) battery powered aircraft, the combined limitations of battery technology (e.g., power storage density) and / or electric motor power-to-weight ratio impose significant constraints on the payload capacity and flight envelope of the aircraft. Since the cruise time is relatively short, a larger portion of the variation in energy expenditure that helps determine the reserve portion required for the aircraft energy budget is reflected in the landing phase of the flight. In some embodiments, the aircraft 1 has a rated payload of between 200-300 kg, a flight time of at least 30 minutes (e.g., 30 minutes, 45 minutes, or 60 minutes), and a maximum rated range of between about 80 km and 150 km (e.g., in the range of 90-120 km).

[0150] It can therefore be appreciated that the ability of the aircraft to reliably and predictably use energy reserves from cruising speed to landing has potentially significant implications for the aircraft's availability for extended flights close to the rated range limit. This reliable predictability is reflected in the consistency of the landing time and / or the consistency of the power level used during the landing phase of the flight, preferably even for pilots who are new to the aircraft, and preferably without placing high demands on the pilot's attention, especially when the pilot is busy evaluating the choice and / or conditions of the landing site 3. Consistency does not necessarily mean that every flight is the same, but rather that the pilot can make a predetermined flight plan based on a confident assumption; for example, the actual landing time and / or energy budget consumed will be within 10%, 20%, or 30% of the predetermined expectation. For example, if the pilot expects that the time from cruising speed to the landing site hovering will not use more than 10% of the total energy budget of the flight, then when deciding whether their battery energy reserves are indeed safe, they can consider that up to 3% additional is needed. This can be a problem for the pilot, for example when making quick decisions and / or evaluating the performance of the aircraft as a function of battery life, charge state and / or weather.

[0151] In some embodiments, the difference in average landing energy budget expenditure among a certain range of pilots with different skill levels (each operating according to the same predetermined landing parameters) (e.g., the 95% of pilots closest to the average level in a randomly selected group of pilots) is insignificant or negligible during planning compared to the impact of changes in other flight conditions such as weather; for example, the impact of weather changes on energy consumption during landing is less than 50% or 25%.

[0152] Reference now Figure 2B, which schematically illustrates the relationship between the horizontal speed (forward speed) and the vertical speed (descent speed) to obtain the glide slope constant k according to some embodiments of the present disclosure. The instantaneous ratio of the descending speed 12 to the forward speed 13 is expressed as And the instantaneous ratio of the forward deceleration 24 and the descending deceleration 25 is expressed as As long as k remains constant, the aircraft will remain on the same glide slope (eg, a slope within the range between glide slope 22A and glide slope 22B, although flatter or steeper glide slopes are not excluded).

[0153] The glide slope 22B again shows a glide slope of about 10°, with (approximately) k=0.18. To maintain this slope, the ratio of the forward speed 13B must (at least on average) remain in a certain ratio to the descent speed 12B; for example, a deceleration is applied at landing so that the forward deceleration 24B and the descent deceleration 25B also maintain the same ratio. For a steeper glide slope 22A, different ratios (between the forward speed 13A and the descent speed 12A, and between the forward deceleration 24A and the landing deceleration 25A) will be maintained; for example, (approximately) k=1.75.

[0154] Cockpit observation and control of the glide slope controlled descent to landing

[0155] Reference now Figure 2C , which schematically illustrates direct joystick adjustment of the glide slope constant k from the perspective of the cockpit 7 of the aircraft 1 according to some embodiments of the present disclosure.

[0156] During the descent to landing, in some embodiments of the present disclosure, the pilot uses the flight controller 505 to set the current value of k (corresponding to the glide slope 4). For example, pushing the flight controller 505 forward will cause k to increase, and accordingly, the descent rate will be steeper. Pulling the flight controller 505 back will cause k to decrease, and accordingly, the descent rate will be gentler.

[0157] Movements of the flight controller 505 are optionally resolved relative (e.g., indicating a rate of change relative to a current state) or absolute (e.g., the position of the flight controller 505 is directly converted to the value of a set parameter, such as a glide slope). A mixture of these parameters may be used, such as a mid-range of movement of the flight controller 505 being resolved absolute relative to some set point (e.g., some altitude), with rate control being performed at the extremes of the controller's range of movement, and the set point also being modified as the controller returns to this mid-range of motion.

[0158] Since the response of the aircraft generally lags behind the input, the operation of the "absolute" mode can be understood as setting the target control value. The flight control logic of the aircraft is preferably configured to handle the switching between flight control modes so that the position of the flight control stick before the switch is not solved in a way that causes a sudden change in the flight of the aircraft after the switch. This may include a gradual switching of the flight controller axis solution, such as a gradual change between relative and absolute control modes, and / or a gradual change in the solution of the flight controller position when the aircraft switches between flight control modes.

[0159] It should be noted that direct coupling of the control axis of the flight controller 505 to k and the glide slope 4 is preferably a special mode of aircraft operation. For example, during cruise flight, the same axis can optionally be matched to another directly controlled parameter; for example, climb rate, aircraft pitch angle, throttle, or a combination of any two or more thereof.

[0160] The glide slope of the aircraft during landing will generally be affected by the positioning of the flight controller 505, for example, the flight surface of the aircraft is changed by its operation. However, it should be emphasized that the actual glide slope produced will generally be affected by other factors (importantly the airspeed of the aircraft), and a skilled pilot must balance these factors with the input provided through the flight controller 505 to keep the aircraft on course. In the embodiment of the present disclosure, the aircraft itself is responsible for maintaining this balance.

[0161] Generally speaking, for an aircraft in flight, "flying where it is pointed" is neither a given nor a default. In particular, during landing operations, fixed-wing aircraft will typically point away from the ground. Also in embodiments of the present disclosure, it should be understood that selecting a glide slope is distinct from selecting the altitude (and particularly the pitch angle) of the aircraft so that it corresponds to the glide slope. In some embodiments, the pitch angle of the aircraft may vary even if the flight controller 505 remains stable as part of the aircraft's effort to maintain a constant ratio of forward speed to descent rate.

[0162] The time between the moment the pilot begins adjusting the glide slope to aim at the target and the moment the aircraft reaches a glide slope consistent with reaching that target (if maintained thereafter) may be only a few seconds, for example the aircraft is aimed at the landing site in 1-20 seconds. Optionally a longer time may be required, for example to suppress the power of the aircraft. For rapid adjustment, it may be particularly appropriate for aircraft that rely primarily on rotor lift to reduce rotor thrust as needed to increase the vertical descent rate. After establishing the glide slope, the pilot is preferably free to indicate updating corrections as appropriate for the remainder of the flight (e.g. until the terminal speed / terminal altitude is reached). Optionally, if the initial course was set correctly and other conditions remain stable, the pilot's indication of updating corrections does not change.

[0163] If the pilot's initial indication of the glide slope is incorrect, the pilot may initially be satisfied that the glide slope is correctly established, but realize upon further descent that the landing site is not being approached directly (e.g., it is drifting in view). The pilot may then naturally enter a phase of providing correction indications to the aircraft, for example based on the angular position of the stable target landing site as perceived by the pilot. Optionally, there is no strong limit on the amplitude of the indication allowed, for example, to allow for changes in the selected landing site. Optionally, the aircraft control system reduces the sensitivity of the system to pilot correction indications after an initial apparently stable selection is made, for example to enhance the pilot's ability to make fine corrections without overcorrecting.

[0164] For steep descent slopes (e.g., including angles of 10°–60° below the horizontal), a potential advantage of the aircraft is to provide the pilot with low-angle forward visibility. In some embodiments of the present disclosure, this is provided by a front lower window 8 that extends upward from about the height of the pilot's feet 501 in an upright sitting position. In some embodiments, footrests 501A define this height. In other words, in level flight, the window includes a viewing area below the horizontal plane of the pilot's waist.

[0165] Therefore, the target landing point 3 is located on or near the current glide slope 4 of the aircraft 1 , and often the target landing point 3 appears to be outside the front lower window 8 to the pilot.

[0166] exist Figure 2C In the example of , the current heading of aircraft 1 is located at the intersection of horizontal line 503 (indicating the ROC of aircraft 1) and vertical line 502 (its bearing). Since the aircraft is not necessarily "pointing" at its current heading, this intersection is not necessarily located at a consistent or predetermined location in the pilot's field of view. Instead (when the aircraft pitch angle α is constant): as k is adjusted up or down, the effect on the glide slope is as if the horizontal line 503 (and therefore the aircraft's expected "contact point" with the ground) is adjusted accordingly (but oppositely) up or down (as shown by the arrowed -k in the figure). In this case, "down and up" also corresponds to "closer and farther away" because the ground is viewed from an oblique angle.

[0167] In some cases, the pitch angle α may also change as k changes, or in other ways, such as as speed decreases. This alone may cause the viewport position (relative to the pilot's perspective) of the intersection between horizontal line 503 and vertical line 502 to change significantly, even though this has no direct relationship to the ground position of that intersection.

[0168] While a pilot generally cannot determine the current target landing site based solely on its relative angular position in the pilot's field of view, the pilot may be able to perceive the target landing site (the aircraft's current heading toward the ground) from the general pattern of optical flow in its vicinity (e.g., as shown by arrow 504). If the location is stable (e.g., no sideslip, aircraft attitude changes, or changes in the glide slope itself), it will be fixed in angle but "growing" while other areas move outward from it. However, at greater distances and / or lower speeds, the center of the optical flow may be difficult to perceptually determine.

[0169] Nevertheless, the pilot can still easily and intuitively keep the aircraft close to the landing site 3 under visual monitoring, even if only by operating the flight controls 505 to keep the visual (angular) position of the target landing site 3 constant, no matter where it is (as long as there is a net decrease in distance and no change in pitch angle is required to reduce speed). If a pitch angle change occurs, the pilot can keep allowing the angular position of the landing site 3 to move, while taking into account the change that has occurred, but not necessarily knowing its precise magnitude. For example, the movement of the horizon line can provide an intuitive visual cue that a pitch angle change is occurring. The sense of balance can also provide a sensory cue, at least when decelerating gently.

[0170] Even if the instantaneous heading of the aircraft 1 remains off course (e.g., due to a pilot's misperception of the true heading), the pilot's continued corrections will gradually bend the aircraft toward the intended landing site. Although a perceived heading error of, say, 15° is very large at a distance of several thousand meters, continued corrections during final approach will cause the absolute error to decrease over time. As the aircraft approaches to within a few meters of the landing site, the same 15° error will be less noticeable - by then, the pilot will generally find it easier to determine the true heading of the then much slower aircraft by intuition and sight, and adjust corrections accordingly.

[0171] Figure 2C Also shown in the figure is a flight instrument panel 506. In some embodiments, it displays information that the pilot can use additionally or alternatively to locate and / or confirm the location of the current target landing site. For example, the flight navigation computer can perform calculations to determine the current target intersection with the ground and optionally display it to the pilot as a map. In another example, the flight navigation computer optionally displays a representation simulating the pilot's perspective, indicating the pilot's subjective direction of the current target intersection with the ground. In another example, a light (e.g., a dot, a crosshair, text and / or a graphic symbol) is projected onto the front lower window 8 itself and is controlled to indicate the location of the currently selected intersection with the ground as perceived by the pilot.

[0172] Optionally or alternatively, the navigation system may use the pilot's navigation input to help determine where the pilot is trying to go (e.g., a point in distance that is maintained at a constant angular position). If this is inconsistent with the aircraft's current course, the pilot may receive suggestions from the system to adjust the course. Optionally, the navigation system itself may adjust the operation of the aircraft to assist the pilot. In some embodiments, the navigation system's estimate of the pilot's intent may be presented to the pilot, and the pilot will have the opportunity to confirm or correct this estimate.

[0173] In some embodiments, once the pilot and the navigation system have jointly confirmed the target landing site, other functions may become available. For example, the navigation system may optionally control the flight operation itself to reach the target landing site (if the pilot permits), and / or suggest to the pilot a faster and / or more energy-efficient route to reach the target landing site. In some embodiments, the flight system uses its own available maps and / or sensor data to evaluate the target landing site; for example, to determine whether there are obstacles that may not yet be visible from the air, to verify that the landing site is sufficiently flat, to check whether the landing site may be susceptible to avalanche or landslide conditions, and / or to check whether there are known issues with landing rights. Optionally, these checks can be performed on the current target route intersection with the ground even if the pilot has not yet explicitly confirmed that it is the target landing site.

[0174] Function-based parameter control during descent for glide slope control

[0175] Common function constraints

[0176] Reference now Figure 2D , which illustrates the relationship between the forward speed v according to some embodiments of the present disclosure. H 、ROCv V , aircraft altitude h (altitude above the landing area), glide slope constant k and velocity function f(h) are related to equations 201, 201B.

[0177] Equation 201lim(h→h offset )v H =0 indicates the end condition of the glide slope: when the aircraft altitude h approaches a certain height above the ground h offset When the final (vertical or near-vertical) landing is completed from this altitude, the forward speed v H Zero (or close to zero, for example, less than 1 m / sec).

[0178] Equation 201Bv V =kv H =f(h) represents Figure 2BThe glide slope equation written in different forms in , and is equivalent to the altitude function f(h). The flight control system of the aircraft 1 can use this function as a function of altitude to adjust the aircraft speed during the descent. In some embodiments, other factors are used to modify f(h) and / or as a proxy for altitude, such as Figure 5 Discussion.

[0179] Speed ​​reduction as a function of altitude

[0180] Reference now Figure 3A , which schematically illustrates the relationship between the ground speed and the altitude of a vertical landing aircraft 1 during a landing approach according to some embodiments of the present disclosure. Figure 3B , which schematically illustrates the relationship between the descent speed (negative ROC) and the altitude of the vertical landing aircraft 1 during the landing approach according to some embodiments of the present disclosure.

[0181] This reflects an embodiment of two control loops: one for ROC and one for forward speed. For example, forward speed is optionally a linear function of height above the ground, offset by some minimum altitude at which minimum speed is achieved and / or glide slope control mode is exited). There is also a maximum altitude above which speed does not increase.

[0182] The ROC also has these characteristics, for example, it is also a maximum above a certain altitude, and reaches zero - at least when landing, and optionally at an offset altitude, where the pilot optionally receives direct control of altitude (e.g., replacing control of descent slope) and has enough time to react appropriately to the situation. In some embodiments, this can be viewed as real-time manipulation of the ROC using the joystick: pushing the joystick forward increases the ROC (in the negative direction) - this makes the approach steeper, and vice versa. For linear deceleration as a function of altitude: a faster steeper approach (as a function of time) reduces both forward speed and descent speed (e.g., the aircraft reaches the ground and the expected minimum forward speed faster). However, compared to any given altitude, a steeper approach will descend faster than a flatter approach, while forward speed optionally remains unchanged. Linear deceleration is not necessarily maintained in all embodiments.

[0183] from Figure 3AStart: The three paths 42, 42A and 42B between point 40 on the slope and the final descent speed / altitude envelope 44 represent a series of different relationships between altitude and ground speed (horizontal / forward flight speed). Path 42 represents a linear altitude / speed relationship, where horizontal speed decreases proportionally as a function of decreasing altitude along a given glide slope. Alternatively, path 42 represents this relationship over any selected glide slope. In this case, the greater the deceleration rate, the steeper the glide slope.

[0184] However, there is no particular requirement that the relationship between ground speed and altitude be linear. Path 42A shows a situation where the speed is decelerated earlier ("faster") than in the linear case. This increases the landing time, but may provide more opportunities to observe (and possibly improve or change) the target landing site. Path 42B shows a situation where the speed is maintained longer than in the linear case. This reduces the landing time. This mode may be suitable to conserve available energy, and / or when the pilot is confident in the suitability of the landing site.

[0185] It should be noted that all of paths 42, 42A, and 42B (including paths between them) are consistent with maintaining a constant glide slope (or even the same constant glide slope). Alternatively, the glide slope may be modified during the descent without necessarily deviating from a given relationship between altitude and forward speed. In some embodiments, the "aggressiveness" of the descent is used to select which particular relationship between ground speed and altitude to use. For example, a steeper descent slope (already faster deceleration on linear path 42) may be associated with a faster deceleration path 42A, which may increase the safety margin and may allow additional time to assess the landing site. The reduction in speed for a more gradual descent may be delayed as a function of altitude (such as path 42B), for example to avoid unduly extending the flight length.

[0186] Alternatively, deceleration as a function of altitude may be more delayed in a rapid descent, consistent with the rapid descent being interpreted as indicating a particular rush to reach the landing site. Conversely, a gentle descent angle may cause the speed to decrease more, for example as if a gentle descent angle indicates an interest in lingering to observe the area.

[0187] Optionally, multiple deceleration modes are available, and the navigation computer of aircraft 1 gives the pilot the opportunity to select which mode is appropriate for his situation. Optionally, the pilot can select the altitude / speed relationship, for example, by selecting an exponential factor to switch from linear to "superlinear" (e.g., path 42A) or "sublinear" (e.g., path 42B). Optionally, this selection is made based on the setting of the throttle input; for example, squeezing the throttle trigger will make the altitude / speed relationship more biased, so that the speed decreases more slowly as a function of altitude (i.e., starting from its current value).

[0188] It is important to note again that the choice of glide slope k is dynamically controlled by the pilot (e.g., by movement of the flight control axes), and optionally modified at any time during the descent, e.g., to select a new landing site. If this k is associated with a speed-altitude function, the aircraft can optionally interpret it as a command to speed up or slow down as necessary to match the "new" path. Alternatively, the aircraft can slow down but not speed up, simply continuing to use the originally selected relationship between ground speed and altitude, or making a partial switch, e.g., depending on how much speed and / or altitude still needs to be discarded.

[0189] The vertical descent of line 43C represents a decrease in altitude at forward cruise speed until a threshold altitude is reached at which the aircraft switches to glide slope control (e.g., the pilot directly selects the glide slope by operating the flight control axis). However, the entry of glide slope control may occur in other ways. Region 43 indicates a series of paths that may cause the glide slope control to switch. For example, a direct descent along line 43A at a constant sub-cruise speed may only trigger the altitude / speed relationship when the actual forward speed intersects the altitude / speed function used during the descent. Alternatively, path 43B represents a descent from an overspeed condition. Optionally (even in the case where glide slope control has not been enabled), the altitude-speed relationship is brought to a higher altitude to help ensure a smooth switch. Alternatively, deceleration is only initiated after glide slope control is enabled (e.g., below the altitude of point 40). In another option, once the aircraft enters the glide slope control mode, the altitude-speed relationship will simply adjust to the current speed. In another option, entry into the glide slope control mode itself occurs at a higher or lower altitude to allow for earlier or later initiation of initial deceleration as appropriate.

[0190] The final landing speed / altitude envelope 44 indicates that the forward speed may actually be reduced to zero over the landing target before the true vertical descent, or may continue to slow from a low but non-zero forward speed as the vehicle completes the landing. Although the figure does not show a non-zero forward speed during landing (glide), this is not excluded.

[0191] Figure 3A The points involved in the paths 42, 42A, and 42B are also generally applicable to Figure 3BPaths 52, 52A, 52B in the altitude-descent speed graph are appropriately varied. In the scenario shown in the figure, it is contemplated that the initial descent rate (e.g., in region 53 defined by paths 53A and 53B) is likely not to fully match the given glide slope initially selected by the pilot. As for the forward speed case, this can be handled in different ways. When the aircraft descends to the on-grade condition at point 50, the options shown adjust the descent speed so that it matches some appropriate "starting" value (e.g., determined to be an appropriate ratio to the current forward speed). Pilot inputs after point 50 are then resolved relative to whatever value is reached. Optionally, there is no such preliminary match, and any current descent speed (based on its ratio to the forward speed) becomes directly the initially selected glide slope at the time of the glide slope control transition. Otherwise, the altitude-speed relationship is optionally handled as described in the ground speed versus altitude graph. On landing, the descent speed must be greater than zero until contact with the ground. Controls and pilot prompts during landing descent

[0192] Reference now Figure 4A -4E, which schematically illustrates multiple stages of a landing approach of a vertical landing aircraft 1 according to some embodiments of the present disclosure.

[0193] exist Figure 4A In some embodiments, aircraft 1 is a fixed-rotor, fixed-wing aircraft whose dynamic characteristics are such that a large portion of the lift is generated by wing 10 at higher forward speeds. In addition, the pitch angle of aircraft 1 adjusts the proportion of thrust generated by rotor 5, which contributes to both lift (vertically) and forward speed (horizontally). The pitch angle can also affect the total thrust, for example, based on the difference in airspeed in the horizontal and vertical directions. This dynamic interaction can be complex in terms of its direct effect on aircraft speed. However, when the pilot directly controls the glide slope, the pilot is buffered by the flight control system of aircraft 1 to protect him from this complexity.

[0194] In some embodiments, the nature of the pilot's control of the aircraft is patterned. For example, there is optionally a mode change from cruise flight to final approach (glide slope control), and optionally a mode change from a glide slope control mode to a vertical descent. It should be understood that there may also be other flight modes, such as takeoff, rise to cruise flight and / or sport flight. Optionally, one or more mode changes are automatic, for example, triggering a change from a cruise flight mode to a glide slope control mode when the aircraft descends below a certain altitude. Optionally, at least in some cases, the pilot can induce or reverse the change in flight mode (e.g., reverse automatic change). The mode change may be instant, but it is not necessary. For example, the meaning of a certain axis input by the pilot to the flight controller 505 can be a smooth change to gradually reduce its effect, which is resolved as a direct indication of the thrust level, and gradually increase its effect, which is resolved as a change in the indication of the glide slope.

[0195] In the situation shown in the figure, the pilot perceives Landing Site 3 in the distance, with an angular magnitude and direction 410A. The angular magnitude and distance to the Landing Site are not to scale, but in this figure, the angular magnitude is "smallest", and the distance is greatest. Since the glide slope 415A is not within the angular position of Landing Site 3, the aircraft 1 overshoots, as shown by the right arrow 411A. Perceptually, the pilot may recognize this overshoot as a tendency for Landing Site 3 to drift lower / closer in his lower field of view.

[0196] Figure 4A The situation may correspond to the pre-landing phase of flight, before the mode in which the pilot directly controls the glide slope is enabled. In this case, the glide slope 415A is a result of other commanded flight conditions of the aircraft 1; for example, as a result of the pilot input to adjust the thrust and / or pitch angle of the aircraft 1.

[0197] Optionally or alternatively, Figure 4A The situation may correspond to a flight phase in which a mode in which the pilot directly controls the glide slope is enabled (eg, at the pilot's request and / or due to descent to the mode activation altitude), but the pilot has not yet aligned the aircraft 1 with its final landing site.

[0198] arrive Figure 4B , direct pilot control of the glide slope is enabled, and the pilot has moved the glide slope control axis of the flight controller 505 to adjust the glide slope 415B so that the aircraft's glide slope coincides with the (now slightly larger) visual angle 410B corresponding to touchdown point 3. In this case, the descent is at 45°, with forward speed 413B and descent speed 412B being equal.

[0199] Optionally, the pilot input controlling the glide slope results in a corresponding angular change 414B in the pitch angle α of the aircraft 1. For example, the flight control system of the aircraft 1 may respond to the pilot input to reduce the glide slope by (1) reducing thrust to increase the descent speed 412B, and (2) increasing the portion of the rotor thrust provided in the forward direction to maintain the forward speed 413B to the descent speed 412B at the pilot-commanded ratio k. During the pitch angle adjustment, the pilot may perceive the landing site 3 as drifting below his field of view (e.g., drifting upward / farther away in this case), even though the aircraft 1 is actually on a glide path directly leading to the landing site 3. However, it is possible that any pitch angle adjustment is immediate in response to the pilot input to modify the glide slope, and that the adjustment is rapid enough that the pilot can attribute it to his own input; once the pilot stops modifying the glide slope, these adjustments cease.

[0200] exist Figure 4C In the embodiment, the glide slope 415C is maintained within the range of the visual angle 410C corresponding to the target landing point 3, while the forward speed 413C and the descending speed 412C are again reduced at a constant ratio.

[0201] However, although the pilot-commanded glide slope 415C remains constant and is centered within the angle 410C corresponding to the landing site 3, the pitch angle α has moved more toward the horizontal direction as shown by arrow 414C. This may be the result, for example, of the flight control system of the aircraft 1 attempting to continue to reduce the forward speed 413C and the descending speed 412C at a constant ratio. For example, the amount of lift provided by the wing 10 may now be sufficiently reduced, thereby requiring the rotor 5 to provide more vertical thrust. In order to avoid increasing forward thrust, the aircraft 1 tilts back toward the horizontal.

[0202] In some cases, automatic pitch angle adjustments performed as part of a speed reduction corresponding to a decrease in altitude may give the pilot a stronger illusion of course drift (e.g., in the closer / lower direction of arrow 411C). However, the pilot may intuitively feel the difference between movement of the entire field of view (such as changes in pitch angle) and movement of the stable portion of the field of view (such as changes in glide slope). In addition, as landing site 3 is approached, it may be easier to confirm that landing site 3 is still in the center of the optical flow close to the ground. Nevertheless, even if the pilot mistakenly attempts to "correct" the opposite illusion, their intuitive continued focus on the angular direction of the stable landing site 3 will still guide the aircraft to the intended destination.

[0203] Also in Figure 4D, glide slope 415D remains within visual angle 410D corresponding to the now approaching target landing site 3, while forward speed 413C and descent speed 412C are again reduced at a constant ratio. At this point, the angular size of landing site 3 (and visual angle 410D) has expanded enough to partially obstruct the pilots' line of sight, but they can see enough of the surroundings and / or landing site 3 itself to maintain their orientation.

[0204] The aircraft pitch angle α is further adjusted by angle change 414D, and the rotor 5 is now placed in a horizontal or near horizontal position, optionally with slight adjustments (e.g., tilted back) where appropriate, to continue to counteract the forward speed 413D. The pilot now has a strong visual cue of his absolute motion relative to the landing site 3, thereby potentially preventing the illusion of confusing the aircraft's glide slope.

[0205] exist Figure 4E In the case of , the vehicle 1 has reached the end of the glide path: it is completely above the landing site 3, the forward speed is cancelled, and the descent speed 412E is kept low from now on to achieve a safe landing. In the static hover mode, all thrust is directed in the vertical direction, ie α is zero.

[0206] The glide slope mode is now optionally canceled. Optionally, the flight controller has set the glide slope before the movement in the axis, and now directs the descent rate 412E of the aircraft 1. The pilot can now look in multiple directions (e.g., including to the side of the aircraft 1) to monitor the position and / or status of the landing site 3 (e.g., within the angular range 410E). The flight control system of the aircraft 1 optionally makes a small angular adjustment 414E to the pitch angle α, if appropriate, to perform position holding above the current ground position.

[0207] Optionally, the switch from the glide slope mode to the final vertical descent mode is performed in a blended (gradual) manner so that the glide slope response of the aircraft 1 to changes in the position of the flight controller 505 gradually becomes weaker (e.g., as a function of height above the ground) in favor of vertical position and / or speed. This change can be asymmetric; for example, it may occur faster in the descending-increasing direction, but may lag in the other direction to allow the pilot to control forward propulsion without necessarily increasing altitude (or without significantly increasing altitude).

[0208] Operation of Glide Slope Control Mode

[0209] Reference now Figure 5 , which is a schematic flowchart of a method for controlling a landing approach of a vertical landing aircraft 1 according to some embodiments of the present disclosure.

[0210] At block 602, the flow chart begins.

[0211] At box 604, in some embodiments, the aircraft flight control system monitors the aircraft state and / or pilot input to determine whether conditions are met to initiate glide slope control of the aircraft. Optionally, glide slope control is initiated by an explicit pilot command. Conditions for automatic switching optionally include descending below a certain altitude, which altitude is optionally predicted based on previous events, such as the time of flying at cruising speed above the altitude. In some embodiments, an emergency switch is initiated to switch to the glide slope control mode in the event of low battery remaining power (and / or otherwise limited energy reserves), and / or damage and / or failure (e.g., of the rotor) is detected.

[0212] From block 606 , in some embodiments, if the conditions for initiating the glide slope control mode are met, the flow chart proceeds to block 610 . Otherwise, the flow returns to block 604 .

[0213] At block 610, in some embodiments, the aircraft altitude h, forward (horizontal) speed v H , descent (vertical) speed v V and the current pilot-commanded glide slope k. In some embodiments, the pilot-commanded glide slope k is provided based on the movement of the flight controller, for example, based on the movement of a specific axis of the flight controller.

[0214] A flight controller (e.g., flight controller 505) optionally has multiple control axes; for example, a primary axis for each of the left / right and forward / reverse motions of a joystick, an axis of rotation (e.g., about a geometric axis extending through the longitudinal axis of the joystick), and one or more secondary axes, such as a directionally placed selector switch, a dual-axis "hat" joystick, one or more throttle axes, and optionally one or more buttons. Preferably, once glide slope control is initiated, the flight controller's primary forward / reverse motion axis becomes the direct control axis for glide slope. Optionally, another axis (e.g., an axis of a dual-axis "hat" joystick) is used instead. The glide slope control axis optionally resolves explicitly to glide slope (relatively, absolutely, or a mixture of these); for example, as Figure 2C Description of the relevant.

[0215] At block 612, in some embodiments, the value accessed at block 610 is compared by function f(h), for example, based on Figure 3A–3B related description of any principle to construct the function. Optionally, additional input from the pilot adjusts f(h), for example, adjusting whether the deceleration occurs slower or faster early on. Optionally, other factors adjust f(h), such as flight time, current speed, current distance from the ground (e.g., along the current glide path), distance to a previous target landing site, or other factors. In addition, it should be understood that the "altitude" as an independent variable of the speed function is optionally replaced by one or more parameters, such as the target landing time, or the remaining distance to the landing site. Conversely, "altitude" can also be understood as a proxy for these parameters and / or a combination of these parameters. However, since the final condition for landing is a zero altitude above the ground, the altitude itself has special importance. The altitude itself can be defined in various ways, such as described in the overview, and optionally the definition used can be dynamically changed when appropriate during the landing process, for example, depending on the proximity of the landing site and / or the characteristics of the intermediate terrain.

[0216] It is possible that there is a difference between the speed indicated by f(h) and the actual speed of the aircraft. For example, the aircraft may enter the glide slope control mode at a speed and altitude that is inconsistent with the altitude / speed function. Optionally, this situation is avoided by adjusting the function f(h) to match the current flight parameters and reducing the speed based on this. Optionally, too large a deviation may prevent entry into the glide slope mode and / or cause exit from the glide slope mode. In some embodiments, the function f(h) is defined to allow entry under several different parameter combinations, optionally using appropriate "funneling" to adjust the aircraft flight parameters so that they tend to the standard flight envelope used during the glide slope control mode.

[0217] In full relative mode, it is optionally possible to avoid having the commanded value of k differ from v by treating the position of the flight controller axis as representing the commanded rate of change of k (whatever it currently is). V and v H The potential benefit of this is that a centered stick position (optionally with a surrounding "dead zone" of no response) can represent no commanded change, which can help the pilot understand what their sensory experience is. The commanded rate of change may not be achieved immediately, for example due to response lag, but the pilot can wait for the cumulative effect.

[0218] However, in some embodiments, the position of the flight controller axis indicates (at least in part) a target value for k. In this case, the control goal of the aircraft flight control system is to reduce the difference between the commanded k and the actual k over time.

[0219] As described, for example, relative to Figure 3A-3B, optionally there is a set of different functions of altitude and speed according to which the aircraft can depart from a given current altitude and speed. Optionally, the set can be selected automatically or by the pilot. Optionally, the set can be selected by a predetermined selection. Optionally, the set is selected dynamically, for example, based on changes in current conditions and / or pilot input.

[0220] At block 614, in some embodiments, the current flight characteristics of the aircraft are appropriately adjusted so that the aircraft altitude h, forward (horizontal) speed v H , descent (vertical) speed v V The expected measured value of the glide slope k currently commanded by the pilot becomes closer to or continues to be consistent with respect to f(h). Generally speaking, the glide slope controlled flight converts the pilot command to select and / or change the glide slope k into aircraft flight parameter adjustments that produce and / or result in matching v V and v H The actual ratio of can be adjusted, for example, by appropriate adjustment of thrust, vehicle pitch angle, and optionally other parameters, such as adjustment of wing shape, activation of secondary thrusters and / or movement of thrust splitter surfaces.

[0221] At the same time, reducing v V and v H , to a certain offset height h above or at ground level offset When v V = 0 (at least approximately). As mentioned above, this reduction can be linear, or it can follow another function. There may be several different but coordinated changes in the flight parameters of the aircraft at the same time - some changes affect one of the two speeds almost independently of the other, and some changes cause changes in the forward speed and the descent speed to be closely correlated (or even negatively correlated).

[0222] In the case where consistency with f(h) has been established, the adjustment of block 614 may include maintaining the current flight characteristics (e.g., continuing to maintain the existing engine power reduction rate), and / or gradually adjusting these characteristics, such as gradually and appropriately adjusting the aircraft pitch angle to make the current relative contribution to the vertical lift of the aircraft wing and the aircraft rotor thrust. When the difference is large, the adjustment can be adaptively made more abrupt, for example, based on safety margins and / or flight comfort considerations.

[0223] At block 616, in some embodiments, a determination is made automatically (or optionally manually) as to whether the glide slope control mode should now be exited (e.g., because the aircraft has reached v H =0 and h=h offsetIf not, the flowchart continues to execute block 610. Otherwise, the flowchart continues to execute block 618 to complete the landing. For example, once the minimum altitude (the minimum altitude of the glide slope, i.e., h offset ), the aircraft's flight control system automatically switches to "hover mode", which maintains altitude above the ground (ROC = 0) unless otherwise requested by the pilot, and allows the pilot to move the aircraft laterally (e.g., left / right and optionally forward / backward) to fine-tune the exact touchdown point.

[0224] At block 620 , after landing, the flowchart ends.

[0225] Flight control system supporting glide slope control mode

[0226] Reference now Figure 6 , which schematically illustrates a flight control system 650 of a vertical landing aircraft 1 according to some embodiments of the present disclosure. The elements of the flight control system 650 specifically related to the glide slope control are emphasized; however, it should be understood that the landing control system 650 includes the function of overall control of the flight of the aircraft 1.

[0227] In some embodiments, the flight computer 651 includes a computer processor and a memory storing instructions that are executed by the computer processor to control the flight characteristics of the aircraft 1. Elements of the aircraft 1 other than the landing control system 650 are described herein, for example, in conjunction with Figure 2A and Figure 2C , for description.

[0228] The flight computer 651 determines the current flight state of the aircraft based on an appropriate combination of data received from the position / velocity sensor 652, other aircraft state sensors / actuators 654, engines 656, and / or map data 657. Position / velocity sensing (including altitude and aircraft attitude sensing, such as pitch, yaw / azimuth, and / or roll) can use any suitable technology or combination of technologies, such as GPS, radio beacons, inertial tracking, magnetic compass, barometric pressure, pitot tubes, and / or MEMS. The aircraft state sensors can provide data such as temperature, battery remaining power, flight time, cabin pressure, and equipment operating status, or any other data generally related to aircraft functions. In particular, the engine 656 can provide information about its current torque and / or rotation rate, such as an indication of thrust and / or performance. In some embodiments, the map data 657 is used to put the sensor data into context; for example, to determine the current absolute altitude and / or predicted altitude along the current or predicted route. The "Actuators" portion of aircraft state sensors / actuators 654 (optional in some embodiments) provides information about the position of actuators of the aircraft, such as the position of movable flight control surfaces, if applicable, where appropriate.

[0229] In some embodiments, the memory of the flight computer 651 includes parameters describing target state information 659, which the computer 651 uses to determine whether adjustments need to be made to the operation of the actuators in the engine 656 and / or the aircraft state sensor / actuator 654 and what adjustments need to be made. Part of the target state information 659 is predetermined, such as parameters that specify how to respond to various data modes to fly correctly in one or more modes. For example, it can describe how the pitch angle and thrust can be changed under the current (controllable) state conditions to advance towards a new (flight) state condition, such as according to instructions entered by the pilot. The target state information 659 is also set in part by pilot input 660, which indicates to the flight computer what the pilot wants to do. It can take many forms, such as autopilot settings, map selections, flight mode settings, and / or instantaneous inputs from flight controls (such as joysticks). The target state information 659 can also describe the conditions for switching flight modes, such as switching from cruise flight to a glide slope control mode for landing approach, and switching from a glide slope control mode to a hovering descent mode during the final stages of landing.

[0230] In some embodiments, in a glide slope control mode (approaching to landing site 3 in part based on a route specified by its slope), pilot input 660 includes a glide slope input 662, such as provided by a motion axis of flight controller 505, such as Figure 2C664, optionally mapped to an active control axis (e.g., a trigger, which acts as a throttle input, or more commonly an airspeed selector input). Additionally or alternatively, the deceleration profile of the descent is set to a persistent parameter (e.g., selection of mode). Optionally, it is fixed, such as a linear deceleration, which is selected where appropriate to achieve reaching the target landing site at an offset position above the ground. The deceleration profile will be, for example, Figure 3A -3B. The pilot also typically controls other inputs 666 where appropriate; for example, yaw angle and / or azimuth are typically controlled by flight controller 505. Other inputs 666 also optionally include, for example, map selections and other navigation inputs, mode selections, and / or parameters that control how flight computer 651 selects from flight control options (e.g., responding with greater or less sensitivity and / or abruptness).

[0231] General

[0232]

[0043] When referring to quantities or values ​​herein, the term "about" means "within ±10%."

[0233] The terms "includes," "comprising," "having" and variations thereof mean "including but not limited to."

[0234] The term "consisting of" means "including and limited to."

[0235] The term "consisting essentially of" means that the composition, method or structure may include additional ingredients, steps and / or components, but only if the additional ingredients, steps and / or components do not materially change the main and novel characteristics of the claimed composition, method or structure.

[0236] As used herein, the singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise. For example, the term "a compound" or "at least one compound" may include a plurality of compounds, including mixtures thereof.

[0237] As used herein, “example” and “exemplary” mean “serving as an example, instance, or illustration.” Any embodiment described as “example” or “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments and / or to exclude the incorporation of features from other embodiments.

[0238] The word “optionally” is used herein to mean “provided in some embodiments and not provided in other embodiments.” Any particular embodiment of the present disclosure may include multiple “optional” features, unless such features conflict with each other.

[0239] In the present application, embodiments may be presented with reference to a range format. It should be understood that the description in a range format is only for convenience and brevity and should not be construed as an immutable limitation on the scope of protection of the description of the present disclosure. Therefore, the description of a range should be deemed to have specifically disclosed all possible sub-ranges and single values ​​within the range. For example, the description of a range such as "from 1 to 6" should be deemed to have specifically disclosed sub-ranges such as "from 1 to 3", "from 1 to 4", "from 1 to 5", "from 2 to 4", "from 2 to 6", "from 3 to 6"; and each single value within the range, such as 1, 2, 3, 4, 5 and 6. This applies regardless of the magnitude of the range.

[0240] Whenever a numerical range is indicated herein (e.g., "10-15," "10 to 15," or any pair of numbers connected by these other similar range indications), the meaning is to include any number (fractional or integer) within the indicated range limits, which also includes the range limits, unless the context clearly dictates otherwise. These phrases used herein are used interchangeably, i.e., "range between" a first indicated number and a second indicated number, "to" a first indicated number, "to" a second indicated number, or "until" a first indicated number (or another such range indicating term) a second indicated number, and are meant to include the first and second indicated numbers and all fractions and integers therebetween.

[0241] Although the description of the present disclosure is provided in conjunction with specific embodiments, many substitutions, modifications and variations are obvious to those skilled in the art. Therefore, it is intended to include all such substitutions, modifications and variations, and they will fall within the spirit and broad scope of the appended claims.

[0242] It is understood that, for the sake of clarity, certain features described in separate embodiments of the present disclosure may also be provided in combination in a single embodiment. Conversely, for the sake of brevity, various features described in a single embodiment may also be provided separately, or in any suitable sub-combination, or appropriately provided in any other described embodiment of the present disclosure. Certain features described in the context of different embodiments should not be considered essential features of those embodiments, unless the embodiment cannot be used without those elements.

[0243] Applicant intends that all publications, patents and patent applications mentioned in this specification be fully incorporated into this specification by reference, to the extent that each individual publication, patent or patent application is specifically and individually noted to be incorporated into this specification by reference when cited. In addition, citing or indicating any reference in this application should not be construed as an admission that the reference can serve as prior art for the present disclosure. As for the section headings used, they should not be construed as necessarily restrictive. In addition, any priority document of the present application is hereby fully incorporated into this specification by reference.

Claims

1. A method for automatically controlling the forward speed and the descending speed of an aircraft during its descent to a landing site, characterized in that: The method comprises: adjusting the target glide slope of the aircraft according to an updated indication from the pilot to correct the target glide slope of the aircraft; As the target glide slope is adjusted, automatically adjusting the speed ratio to correspond to the descent of the aircraft along the target glide slope; and while automatically reducing the forward speed from the starting speed to the ending speed, maintaining the ratio of the speeds corresponding to the target glide slope; The start speed and the end speed differ from each other by at least half of the start speed of the aircraft. 2 . The method of claim 1 , wherein the termination speed is less than 10% of the start-up speed of the aircraft. The method of claim 2 , wherein the terminal velocity is stationary.

4. The method according to any one of claims 1 - 2, wherein the start-up speed is at least 80% of the design cruising speed of the aircraft.

5. The method according to any one of claims 1-4, comprising landing the aircraft at the landing site, wherein the terminal speed is reached when the aircraft is above the landing site.

6. The method of any one of claims 1-4, wherein the aircraft descends from a start altitude to a termination altitude while slowing from the start speed to the termination speed, and a ratio of the start altitude to the termination altitude is within three times a ratio of the start speed to the termination speed.

7. The method according to claim 6, wherein: The forward speed decreases approximately linearly as a function of altitude over at least half of the difference between the start altitude and the end altitude.

8. The method according to any one of claims 6-7, wherein: The deceleration of the forward speed as a function of altitude includes a deceleration that increases within at least 10% of a difference between the starting altitude and the ending altitude.

9. The method according to any one of claims 6 to 8, wherein: The deceleration of the forward speed as a function of altitude includes a deceleration that decreases within at least 10% of a difference between the starting altitude and the ending altitude.

10. The method according to any one of claims 6-7, wherein: The forward speed decreases linearly on average as a function of altitude over at least 90% of the difference between the start altitude and the end altitude.

11. The method according to any one of claims 6-10, wherein the termination height is within 2 meters from the landing site in the vertical direction.

12. The method according to claim 10, wherein the termination height is within 0.5 meters from the landing site in the vertical direction.

13. The method according to any one of claims 11-12, wherein the terminal velocity is less than 2 m / s.

14. The method of claim 13, wherein the terminal velocity is stationary.

15. The method according to any one of claims 7-14, wherein the termination altitude and the termination speed are reached at a position above the landing site.

16. The method of claim 15, comprising hovering said aircraft at said position above said landing site.

17. The method according to any one of claims 1 to 16, wherein the time course of the modified update indication comprises: a first phase, in which the correction results in a modification of the target glide slope until the flight path of the aircraft descending along the target glide slope targets the landing site; as well as The second stage is after the first stage. In the second stage, the correction keeps the flight path of the aircraft aimed at the landing site and keeps descending along the target glide slope.

18. The method according to any one of claims 1 to 16, wherein the time course of the modified update indication comprises: a first phase, in which the correction results in a modification of the target glide slope until the flight path of the aircraft descending along the target glide slope aims at a position away from the touchdown site; as well as In the second stage, the correction adjusts the flight path of the aircraft toward the landing site along the adjustment value of the target glide slope.

19. The method of any one of claims 1 - 18, wherein the pilot communicates the updated indication of the correction by adjusting an axis of a flight control.

20. The method of claim 19, comprising upon reaching the terminal velocity: ceasing to adjust the ratio of the speeds to correspond to a descent of the aircraft along the target glide slope; and The axis of the flight controller is used as an indication of a target flight parameter other than glide slope.

21. The method of claim 20, wherein the target flight parameters include movement of the aircraft along only one vertical height direction and a direction orthogonal to the vertical height.

22. The method according to any one of claims 1 to 21, wherein: After reaching the terminal speed, the aircraft remains airborne but the altitude of the aircraft is no longer adjusted based on the updated indication of the correction to the target glide slope.

23. The method according to any one of claims 1 to 22, wherein: Maintaining the ratio corresponds to the target glide slope so that the aircraft moves along a glide path, wherein the movement along the glide path includes a forward descent movement along a straight line, during which the target glide slope remains unchanged and the lateral movement of the aircraft remains constant.

24. The method according to any one of claims 1-23, wherein the update indication of the correction and the subsequent maintenance of the ratio of the speed produce a glide path corresponding to the target glide slope, and the glide path guides the flight path of the aircraft toward a ground position closer to or farther from the aircraft according to the steeper or shallower target glide slope indicated by the correction.

25. The method according to any one of claims 1-24, wherein the revised update indication and the subsequent maintaining of the ratio of the speeds produce a glide path corresponding to the target glide slope, the glide path descending toward the landing site at a relatively higher speed to achieve a relatively steeper target glide slope, and the same forward speed.

26. The method of any one of claims 1-25, wherein the updated indication of the correction is determined by the pilot based on the pilot's direct view of the location of the landing site at an angle of 10° or more below horizontal.

27. The method of claim 26, wherein the updated indication of the correction is determined by the pilot based on the pilot's direct view of the position of the touchdown site at an angle of 30° or more below horizontal.

28. The method according to any one of claims 26 - 27, wherein the direct view of the position of the landing site by the pilot is through a window portion of the aircraft located below the pilot's waist level.

29. The method according to any one of claims 26-28, wherein the pilot's direct view of the position of the landing site is through a window portion, which is located adjacent to the pilot's footrests from the pilot's perspective.

30. The method of any one of claims 1-25, wherein the updated indication of the correction is determined by the pilot based on a camera view of the touchdown site at an angle of 30° or more below horizontal.

31. A flight control system for a vertical landing aircraft, comprising a processor and a memory including instructions, characterized in that: The instructions instruct the processor to: adjusting the target glide slope of the aircraft according to an updated indication from the pilot to correct the target glide slope of the aircraft; As the target glide slope is adjusted, a ratio of the forward speed to the descending speed is adjusted to correspond to the descent of the aircraft along the target glide slope; as well as while automatically reducing the forward speed from the starting speed to the ending speed, maintaining the ratio corresponding to the target glide slope; The start speed and the end speed differ from each other by at least half of the start speed.

32. A flight control system according to claim 31, comprising said aircraft.

33. A flight control system according to any one of claims 31 - 32, wherein the terminal speed is stationary and the start speed is at least 80% of the design cruising speed of the aircraft.

34. A flight control system according to any one of claims 31-33, wherein the aircraft descends from a start altitude to a terminal altitude while slowing from the start speed to the terminal speed, and the ratio of the start altitude to the terminal altitude is within three times the ratio of the start speed to the terminal speed.

35. The flight control system of claim 34, wherein the termination altitude and the termination speed are reached at a position above a landing site, at which position the flight control system maintains the aircraft in a hovering state.

36. A method for a pilot to land an aircraft, characterized in that: include: looking out of the aircraft in a downward direction through a forward-facing window adjacent to a footrest for the pilot's feet; identifying a visible landing site along the downward direction through the front window; as well as An approach is made toward the landing site while reducing speed and altitude until the aircraft touches down at the landing site at a stationary forward speed.

37. The method of claim 36, wherein the approach is performed while maintaining a forward speed and a descent speed proportional, the proportion establishing a glide slope that guides the aircraft to the touchdown location.

38. A method according to any one of claims 36 to 37, wherein the approach is performed while reducing forward speed using a function of decreasing vertical distance from the touchdown site.

39. An aircraft, characterized in that: include: a forward lower position window including an area located below the waist of a pilot in an upright sitting position during forward level flight of the aircraft; as well as A light, positioned to project one or more target indications into the pilot's field of view using the window as a reflective surface.

40. A method of flying an aircraft, characterized in that: include: providing a first sequence of flight direction indications to the aircraft using movement of a flight controller along an axis, wherein the first sequence of flight direction indications controls a glide slope setting for determining a glide path for the aircraft; and providing a second sequence of flight direction indications to the aircraft using movement of the flight control along the same axis, wherein the second sequence of flight direction indication controls is one of the group consisting of: horizontal but not vertical motion of the aircraft, vertical but not horizontal motion of the vehicle, and The pitch angle of the aircraft, but not the horizontal or vertical movement of the aircraft.

41. A vertical landing aircraft having a computerized flight control system providing an enhanced flight mode for the aircraft, characterized in that: The computerized flight control system maintains a fixed ratio between the forward speed and the vertical speed of the aircraft while decreasing both speeds toward a stationary landing speed as a function of altitude above the ground.

42. The aircraft of claim 41, comprising a transparent window which, from the perspective of a pilot of the aircraft in an upright sitting position, faces downward toward the ground, through which the landing area reached when reaching static speed is visible during descent and speed reduction.

43. An aircraft according to claim 41, comprising a camera facing downward toward the ground; and a display screen that displays a view to the pilot of the aircraft in which the landing area reached when reaching static speed is seen during descent and speed reduction.

44. A computerized flight control system, characterized in that: It is configured to maintain a fixed ratio between the forward and vertical speeds of the aircraft while causing both speeds to decrease toward a stationary landing speed as a function of altitude above the ground.

45. A computerized flight control system as claimed in claim 44 wherein the stationary landing speed is achieved in the hover mode when zero forward speed is reached near zero altitude.

46. ​​A computerised flight control system according to any one of claims 44-45, wherein the fixed ratio selects the location of the target landing area, and the fixed ratio is selected in accordance with adjustment of control column movement.

47. A computerized flight control system according to claim 46, wherein the target landing area is adjusted by changing the descent angle in response to the control column movement, the changing comprising replacing the fixed ratio with a ratio corresponding to the changed descent angle.

48. A computerized flight control system according to claim 47, wherein the flight control system adjusts the target landing area by changing the descent rate and / or forward speed deceleration in response to the replaced fixed ratio value.

49. A method for vertically landing an aircraft, characterized in that: The method includes automatically maintaining a fixed ratio between the forward speed and the vertical speed of the aircraft while reducing both speeds toward a stationary landing speed as a function of altitude above the ground.

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