Aircraft stability verification method

Abstract

The invention discloses an aircraft stability verification method, and relates to the technical field of aircrafts, and the method comprises the steps: building a fixed straight flight state of an aircraft after balancing according to an aircraft test working condition, and the aircraft test working condition is obtained through the division according to a thrust vector angle or a tilting mechanism actuation angle; under the condition that the aircraft is in the straightened flight state after trimming, inputting disturbance to the aircraft so as to enable the aircraft to be in a longitudinal oscillation state, and collecting flight parameter data of the aircraft; and determining a stability verification result of the aircraft under the aircraft test working condition according to the flight parameter data of the aircraft. According to the scheme, the test and analysis of the longitudinal dynamic stability of the tilt-rotor aircraft are realized, so that the safety of the tilt-rotor aircraft in configuration design is accurately determined, and the flight safety of the aircraft is improved.

Description

Technical Field

[0001] This application relates to the field of aircraft technology, and in particular to a method for verifying aircraft stability. Background Technology

[0002] During the horizontal flight process of a tiltrotor aircraft from its rotor configuration, the downwash of its own rotor disturbs the airflow on the lift surface, which can easily cause intensified or divergent oscillations in the pitch direction, resulting in strong pitch oscillations and inducing aircraft stall, leading to flight accidents.

[0003] However, the longitudinal dynamic stability of tiltrotor aircraft is still in the research stage, and the verification ideas and methods for the longitudinal dynamic stability of tiltrotor aircraft are still unexplored.

[0004] Therefore, it is necessary to propose a verification method for the longitudinal dynamic stability of tiltrotor aircraft.

[0005] The above content is only used to help understand the technical solution of this application and does not represent an admission that the above content is prior art. Summary of the Invention

[0006] The main purpose of this application is to provide a method for verifying the stability of aircraft, aiming to solve the technical problem of the lack of verification methods for the longitudinal dynamic stability of tiltrotor aircraft in the industry.

[0007] To achieve the above objectives, this application proposes an aircraft stability verification method, which is applied to a tiltrotor aircraft. The aircraft stability verification method includes:

[0008] Based on the test conditions of the aircraft, the straight flight state of the aircraft after trim is established. The test conditions of the aircraft are obtained by dividing the thrust vector angle or the tilt mechanism actuation angle.

[0009] When the aircraft is in the trimmed, upright flight state, a disturbance is input to the aircraft to make it oscillate longitudinally, and the flight parameter data of the aircraft is collected.

[0010] Based on the flight parameter data of the aircraft, the stability verification results of the aircraft under the test conditions are determined.

[0011] In one embodiment, the aircraft test conditions include a first-level test condition. Before the step of establishing the trimmed, stationary flight state of the aircraft based on the aircraft test conditions, the following steps are included:

[0012] According to the preset angle interval, the thrust vector angle or tilting mechanism actuation angle of the preset test range is divided to obtain several first-level test conditions.

[0013] In one embodiment, the first-level test condition includes a second-level test condition. After the step of dividing the thrust vector angle or tilting mechanism actuation angle of the preset test interval according to a preset angle interval to obtain several first-level test conditions, the following steps are included:

[0014] Based on the preset first quantity and the first-level test conditions, a number of the second-level test conditions are determined.

[0015] In one embodiment, the first-level test condition includes a second-level test condition. After the step of dividing the thrust vector angle or tilting mechanism actuation angle of the preset test interval according to a preset angle interval to obtain several first-level test conditions, the following steps are included:

[0016] Based on the flight envelope, weight and center of gravity analysis data of the aircraft, and tilt downwash airflow analysis data, at least one first angle test range and one second angle test range of the aircraft are determined.

[0017] Increase the number of Level 1 test conditions within the first angle test range;

[0018] And / or, reduce the number of Level 1 test conditions within the second angle test range.

[0019] In one embodiment, after the step of determining a plurality of secondary test conditions based on a preset first quantity and the primary test conditions, the method further includes:

[0020] Based on the flight envelope, weight and center of gravity analysis data of the aircraft, and tilt downwash airflow analysis data, at least one first angle test range and one second angle test range of the aircraft are determined.

[0021] Based on a preset second quantity, the number of secondary test conditions under the primary test condition within the first angle test range is increased, wherein the preset second quantity is greater than the preset first quantity; and / or

[0022] According to a preset third quantity, the number of secondary test conditions under the primary test condition within the second angle test interval is reduced, wherein the preset third quantity is less than the preset first quantity.

[0023] In one embodiment, the step of establishing the trimmed, stationary flight state of the aircraft based on the aircraft test conditions includes:

[0024] Based on the test conditions of the aircraft, determine the corresponding thrust vector angle or tilt mechanism actuation angle;

[0025] The aircraft is trimmed to establish a stationary flight state after trimming at the thrust vector angle or tilt mechanism actuation angle.

[0026] In one embodiment, the stability verification result includes longitudinal dynamic stability verification results. The step of determining the stability verification result of the aircraft under the test conditions based on the aircraft's flight parameter data includes:

[0027] Based on the flight parameter data of the aircraft, determine the oscillation period and oscillation amplitude of the aircraft under longitudinal oscillation conditions;

[0028] Based on the oscillation period and oscillation amplitude, it is confirmed whether the aircraft meets the heavy damping characteristics, and the longitudinal dynamic stability verification result of the aircraft under the test conditions is obtained.

[0029] In one embodiment, the disturbance includes a short-period longitudinal disturbance, the longitudinal oscillation state includes a longitudinal short-period oscillation state, and the method further includes:

[0030] Based on the pilot's first longitudinal control action, a short-period longitudinal disturbance in the form of a single pulse and / or a double pulse is input to the aircraft to put the aircraft into a short-period longitudinal oscillation state, and flight parameter data of the aircraft is collected. The oscillation period and amplitude of the aircraft in the short-period longitudinal oscillation state are determined based on the flight parameter data; or

[0031] Based on a preset first single-pulse signal and / or double-pulse signal, a short-period longitudinal disturbance is input to the aircraft to make the aircraft put into a longitudinal short-period oscillation state, and the flight parameter data of the aircraft is collected. Based on the flight parameter data, the oscillation period and oscillation amplitude of the aircraft in the longitudinal short-period oscillation state are determined.

[0032] In one embodiment, the disturbance further includes a long-period longitudinal disturbance, and the longitudinal oscillation state further includes a long-period longitudinal oscillation state; the method further includes:

[0033] Based on the pilot's second longitudinal control action, a long-period longitudinal disturbance in the form of a single pulse is input to the aircraft to put it into a long-period longitudinal oscillation state. Flight parameter data of the aircraft is collected, and the oscillation period and amplitude of the aircraft in the long-period longitudinal oscillation state are determined based on the flight parameter data; or

[0034] According to the preset second single pulse signal, a long-period longitudinal disturbance is input to the aircraft to make the aircraft put into a long-period longitudinal oscillation state, and the flight parameter data of the aircraft is collected. Based on the flight parameter data, the oscillation period and oscillation amplitude of the aircraft in the long-period longitudinal oscillation state are determined.

[0035] In one embodiment, the step of determining the oscillation period and amplitude of the aircraft in a longitudinal long-period oscillation state based on flight parameter data includes:

[0036] Based on the flight parameter data of the aircraft, construct the envelope curve of the flight parameter offset value versus time under the longitudinal long-period oscillation state of the aircraft;

[0037] Based on the envelope curve of the flight parameter offset value versus time, the oscillation period and oscillation amplitude of the aircraft in the longitudinal long-period oscillation state are determined.

[0038] One or more technical solutions proposed in this application have at least the following technical effects:

[0039] The aircraft stability verification method proposed in this application specifically involves establishing a trimmed, upright flight state of the aircraft based on the aircraft test conditions, wherein the test conditions are determined by dividing the test state according to the thrust vector angle or the tilt mechanism actuation angle; while the aircraft is in the trimmed, upright flight state, a disturbance is input to the aircraft to induce longitudinal oscillation, and flight parameter data of the aircraft is collected; based on the flight parameter data, the stability verification result of the aircraft under the test conditions is determined.

[0040] This application first determines the test conditions corresponding to different thrust vector angles or tilt mechanism actuation angles during the horizontal flight process of a tiltrotor aircraft from its rotor configuration. Then, during each test, a trimmed, upright flight state of the aircraft corresponding to the test condition is established. While the aircraft is in the trimmed, upright flight state, a disturbance is input to the aircraft to induce longitudinal oscillation, and flight parameter data is collected. This flight parameter data is then analyzed to obtain the stability verification results of the aircraft. Through the above scheme, the longitudinal dynamic stability of the tiltrotor aircraft is tested and analyzed to accurately determine the safety of the tiltrotor aircraft in its configuration design and flight control design, thereby improving the flight safety of the aircraft. Attached Figure Description

[0041] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0042] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 This is a flowchart illustrating an embodiment of the aircraft stability verification method of this application.

[0044] Figure 2 This is a flowchart illustrating Embodiment 2 of the aircraft stability verification method of this application.

[0045] Figure 3 This is a flowchart illustrating Embodiment 3 of the aircraft stability verification method of this application.

[0046] Figure 4 This is a flowchart illustrating Embodiment 4 of the aircraft stability verification method of this application.

[0047] Figure 5 This is a flowchart illustrating Embodiment 5 of the aircraft stability verification method of this application.

[0048] The purpose, features, and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0049] It should be understood that the specific embodiments described herein are merely illustrative of the technical solutions of this application and are not intended to limit this application.

[0050] To better understand the technical solution of this application, a detailed description will be provided below in conjunction with the accompanying drawings and specific implementation methods.

[0051] The main solution of this application embodiment is as follows: Based on the aircraft test conditions, establish the aircraft's trimmed, upright flight state, where the test conditions are determined by dividing the test state according to the thrust vector angle or the tilt mechanism actuation angle; while the aircraft is in the trimmed, upright flight state, input a disturbance to the aircraft to induce longitudinal oscillation, and collect the aircraft's flight parameter data; based on the aircraft's flight parameter data, determine the stability verification result of the aircraft under the test conditions.

[0052] Technical terms used in this application:

[0053] Tiltrotor aircraft: A type of aircraft that combines the high-speed cruise capability of a fixed-wing aircraft with the vertical takeoff and landing characteristics of a helicopter. Its core feature is that the rotor can tilt relative to the fuselage. Tiltrotor aircraft include aircraft in which at least some rotors are tilt rotors. That is to say, a tilt rotor aircraft can have all rotors as tilt rotors, or some rotors as tilt rotors and some rotors as fixed rotors.

[0054] Tiltrotor aircraft possess excellent vertical takeoff and landing (VTOL) performance, do not require long runways, and are capable of operating in urban areas and other space-constrained regions. Simultaneously, in horizontal flight, they exhibit speeds and ranges approaching those of fixed-wing aircraft. Tiltrotor aircraft can be fuel-powered or electric-powered. Electric-powered tiltrotor aircraft, also known as eVOTL (Electric Vertical Take-off and Landing), are used in urban air mobility, low-altitude rescue, and low-altitude logistics.

[0055] In this embodiment, for ease of description, the aircraft stability verification equipment will be used as the subject of the description.

[0056] During the process of establishing horizontal flight from the rotor configuration, the downwash of the rotor itself disturbs the airflow on the lift surface, which can easily cause aggravated or divergent oscillations in the pitch direction, resulting in strong pitch oscillations and inducing aircraft stall, leading to flight accidents.

[0057] However, the longitudinal dynamic stability of tiltrotor aircraft is still in the research stage, and the verification ideas and methods for the longitudinal dynamic stability of tiltrotor aircraft are still unexplored.

[0058] Therefore, it is necessary to propose a verification method for the longitudinal dynamic stability of tiltrotor aircraft.

[0059] This application provides a solution that first determines the test conditions corresponding to different thrust vector angles or tilt mechanism actuation angles during the horizontal flight process of a tiltrotor aircraft from its rotor configuration. Then, during each test, a trimmed, upright flight state of the aircraft corresponding to the test condition is established. While the aircraft is in the trimmed, upright flight state, a disturbance is input to the aircraft to induce longitudinal oscillation, and flight parameter data is collected. This flight parameter data is then analyzed to obtain the stability verification results of the aircraft. This solution enables the testing and analysis of the longitudinal dynamic stability of the tiltrotor aircraft, accurately determining the safety of the tiltrotor aircraft's configuration and flight control design, and improving the aircraft's flight safety.

[0060] It should be noted that the executing entity in this embodiment can be a computing service device with data processing, network communication, and program execution functions, such as a tablet computer, personal computer, or mobile phone, or an electronic device or aircraft stability verification device capable of performing the above functions. The following description uses an aircraft stability verification device as an example to illustrate this embodiment and the subsequent embodiments.

[0061] Based on this, the embodiments of this application provide a method for verifying the stability of an aircraft, referring to... Figure 1 , Figure 1 This is a flowchart illustrating the first embodiment of the aircraft stability verification method of this application.

[0062] The aircraft stability verification method is applied to tiltrotor aircraft, and the aircraft stability verification method includes steps S110 to S130:

[0063] Step S110: Based on the test conditions of the aircraft, establish the trimmed and upright flight state of the aircraft. The test conditions of the aircraft are obtained by dividing the thrust vector angle or the tilt mechanism actuation angle.

[0064] It should be noted that the thrust vector angle refers to the angle between the thrust direction generated by the rotor of a tiltrotor aircraft and the longitudinal axis of the aircraft body; the tilt mechanism actuation angle refers to the rotation angle of the tilt mechanism in a tiltrotor aircraft, which is used to change the thrust direction of the rotor, relative to the reference position.

[0065] While there are existing testing methods for the longitudinal dynamic stability of common aircraft (such as fixed-wing aircraft or helicopters), tiltrotor aircraft, due to their tilting mechanism, are prone to pitch oscillations (i.e., longitudinal oscillations) during the horizontal flight transition from rotor configuration to horizontal flight. When these longitudinal oscillations intensify or diverge, they can pose a significant threat to flight safety.

[0066] In this embodiment, considering the safety of the configuration and flight control design of the tiltrotor aircraft, a stability verification method for the aircraft is proposed. According to the actual test requirements, the thrust vector angle or tilt mechanism actuation angle of the tiltrotor aircraft is divided into several intervals. At least one test condition of the aircraft is selected in each interval, thereby obtaining multiple test conditions of the tiltrotor aircraft from vertical take-off and landing mode to cruise flight mode. This allows for a comprehensive verification of the stability of the aircraft under different thrust direction configurations, ensuring the comprehensiveness and reliability of the verification results.

[0067] It should be understood that in order to verify the longitudinal dynamic stability of a tiltrotor aircraft, the aircraft needs to be in a trimmed, upright flight state under the current test conditions. This allows the aircraft to enter a longitudinal oscillation state after being subjected to an input disturbance, and then the disturbance resistance capability of the aircraft in the longitudinal oscillation state after being subjected to a disturbance can be analyzed, that is, the longitudinal dynamic stability.

[0068] Based on the flight parameter information contained in the aforementioned test conditions, the aircraft is controlled and manipulated in the test environment to establish the trimmed and stable flight state of the aircraft in the test environment. This ensures that the initial flight state of the aircraft is stable in subsequent disturbance tests and avoids interference with the stability verification results due to deviations in the initial flight state.

[0069] In this application, trim refers to the aircraft's ability to maintain stable, level flight when its control systems are in the trim position and no longer moving. The aircraft's control systems include: an all-moving horizontal stabilizer, ailerons, elevators, and rudders, or an elevator-rudder mounted on a V-tail that functions as both rudder and elevator. The horizontal stabilizer and elevator affect longitudinal trim, while the ailerons and rudder affect lateral trim. Only after both longitudinal and lateral trim are completed can the aircraft maintain stable, level flight. After trim is complete, the aircraft is in a state of force equilibrium, i.e., lift = gravity, thrust = drag, and resultant moment in all directions = 0.

[0070] Vertical flight refers to a flight mode in which an aircraft maintains a fixed flight state or path without making any changes in attitude or propulsion. In vertical flight, the aircraft's motion parameters (such as attitude, speed, and altitude) remain constant, and the aircraft's control input remains relatively stable.

[0071] For tiltrotor aircraft, the stationary flight state refers to the aircraft maintaining a horizontal flight attitude with a constant speed, heading, and altitude at a fixed thrust vector angle or tilt mechanism actuation angle, without tilting or changing flight modes.

[0072] In one implementable embodiment, step S110 includes steps S1101 to S1102:

[0073] Step S1101: Determine the corresponding thrust vector angle or tilt mechanism actuation angle based on the test conditions of the aircraft.

[0074] Step S1102: Trim the aircraft to establish a stationary flight state of the aircraft after trimming at the thrust vector angle or tilt mechanism actuation angle.

[0075] Specifically, when the test condition of the aircraft is Level 1, the aircraft stability verification equipment needs to determine the required thrust vector angle or tilt mechanism actuation angle corresponding to the condition; when the test condition of the aircraft is Level 2, in addition to determining the required thrust vector angle or tilt mechanism actuation angle corresponding to the condition, the aircraft stability verification equipment also needs to determine the values ​​of other test parameters of the aircraft corresponding to Level 2, so as to subsequently construct the aircraft's trimmed and upright flight state.

[0076] Then, through numerical simulation or wind tunnel testing, the trim parameters required for the aircraft to achieve a steady flight state under the test conditions are calculated, such as the control surface deflection angle and rotor collective pitch. Based on the trim parameters, the steady flight state of the aircraft after trimming under the thrust vector angle or tilt mechanism actuation angle is established.

[0077] Step S120: When the aircraft is in the trimmed and stationary flight state, a disturbance is input to the aircraft to make the aircraft oscillate longitudinally, and the flight parameter data of the aircraft is collected.

[0078] Step S130: Determine the stability verification result of the aircraft under the test conditions based on the flight parameter data of the aircraft.

[0079] It should be noted that disturbance refers to external interference applied to an aircraft to stimulate its dynamic response, such as elevator pulse input or rotor collective pitch step input. Longitudinal oscillation refers to the state in which the aircraft exhibits periodic motion in the pitch plane, typically manifested as periodic changes in parameters such as airspeed, pitch angle, pitch rate, longitudinal acceleration, thrust vector, elevator skewness, and rotor tilt angle. It should be understood that the collected flight parameters include, but are not limited to, at least one of the following parameters: airspeed, pitch angle, pitch rate, longitudinal acceleration, thrust vector, elevator skewness, and rotor tilt angle.

[0080] Specifically, with the aircraft in a trimmed, stationary flight state, a disturbance is introduced to change the aircraft from this state to a longitudinal oscillation state. Flight parameter data is collected from the start of the disturbance, and this data is analyzed to determine how the flight parameters change in response to the disturbance. By confirming whether the changes in the flight parameters in response to the disturbance meet expectations, the stability verification results of the aircraft can be obtained.

[0081] Furthermore, the aircraft test conditions include Level 1 test conditions, and before step S110, step A01 is included:

[0082] Step A01: Divide the thrust vector angle or tilting mechanism actuation angle of the preset test interval according to the preset angle interval to obtain several first-level test conditions.

[0083] It should be noted that Level 1 test conditions refer to the test conditions of an aircraft as defined by the thrust vector angle or the tilt mechanism actuation angle.

[0084] Additionally, it should be noted that the preset angle interval is a fixed angle increment designed by relevant personnel based on actual test requirements to divide the aircraft test conditions. It is used to discretize the thrust vector angle or tilt mechanism actuation angle of a continuous interval into several primary test conditions. The preset test interval refers to a continuous range of thrust vector angles or tilt mechanism actuation angles defined by relevant personnel based on actual test requirements, typically needing to cover the angle change range during the aircraft rotor tilting process. The preset first quantity refers to the number of tests under the primary test conditions pre-set by relevant personnel based on actual test requirements.

[0085] Specifically, the aircraft stability verification equipment divides the preset test interval according to the preset angle interval to obtain several test sub-intervals. Based on the thrust vector angle or tilt mechanism actuation angle corresponding to the values ​​at both ends of the several test sub-intervals, it determines multiple first-level test conditions with different thrust vector angles or tilt mechanism actuation angles.

[0086] In another embodiment, the primary test condition includes a secondary test condition, and after step A01, step A02 is further included:

[0087] Step A02: Based on the preset first quantity and the first-level test conditions, determine a number of the second-level test conditions.

[0088] It should be noted that the secondary test condition refers to the aircraft test condition under the primary test condition obtained by further dividing the test based on other test parameters of the aircraft, under the condition of a fixed thrust vector angle or tilt mechanism actuation angle. The primary test condition and the secondary test condition are subordinate to each other, with multiple secondary test conditions set under the primary test condition.

[0089] Specifically, multiple different values ​​of other test parameters of the aircraft within the testable range are selected, and combined with the first-level test conditions, a first number of second-level test conditions are obtained under the first-level test conditions. The number of values ​​of other test parameters within the testable range must meet the first number of preset conditions, and one of the other test parameters of the aircraft is preferably speed.

[0090] It should be understood that the values ​​of multiple other test parameters corresponding to the first number of preset second-level test conditions under each first-level test condition may be different.

[0091] This application, through the aforementioned scheme, first determines the test conditions corresponding to different thrust vector angles or tilt mechanism actuation angles during the horizontal flight process of a tiltrotor aircraft from its rotor configuration. Then, during each test, a trimmed, upright flight state of the aircraft corresponding to the test condition is established. While the aircraft is in the trimmed, upright flight state, a disturbance is input to the aircraft to induce longitudinal oscillation, and flight parameter data is collected. This flight parameter data is then analyzed to obtain the stability verification results of the aircraft. Through the above scheme, the longitudinal dynamic stability of the tiltrotor aircraft is tested and analyzed, so as to accurately determine the safety of the tiltrotor aircraft in configuration design and flight control design, and improve the flight safety of the aircraft.

[0092] Based on the first embodiment of this application, in the second embodiment of this application, the content that is the same as or similar to that of Embodiment 1 and / or Embodiment 2 described above can be referred to the above description, and will not be repeated hereafter. Based on this, please refer to... Figure 2 , Figure 2 This is a flowchart illustrating the second embodiment of the aircraft stability verification method of this application. Following the step of determining a plurality of secondary test conditions based on a preset first quantity and the primary test conditions, the method further includes steps S210 to S230:

[0093] Step S210: Based on the flight envelope, weight center of gravity analysis data, and tilt downwash airflow analysis data of the aircraft, determine at least one first angle test range and one second angle test range of the aircraft.

[0094] It should be noted that the flight envelope refers to the tilt angle-velocity envelope of a tiltrotor aircraft during rotor tilting, obtained by relevant personnel based on CFD (Computational Fluid Dynamics) numerical simulations or wind tunnel tests; the weight and center of gravity analysis data refers to the data on the change of the center of gravity of the tiltrotor aircraft during rotor tilting, obtained based on CFD numerical simulations or wind tunnel tests, considering the empty aircraft or load distribution; and the tilt downwash airflow analysis data refers to the airflow disturbance generated by the downwash airflow induced by the rotor sweeping the lifting surface during rotor tilting, as well as the attitude change data of the aircraft under the influence of the tilt downwash airflow, obtained by CFD numerical simulations or wind tunnel tests.

[0095] Specifically, since the flight envelope refers to the range of airspeed of an aircraft at different tilt angles (i.e., thrust vector angles or tilt mechanism actuation angles), when determining the test range, it is necessary to ensure that the thrust vector angle or tilt mechanism actuation angle of the aircraft test conditions, as well as the selected airspeed value, are all within the tilt angle-velocity envelope. In other words, given the selected thrust vector angle or tilt mechanism actuation angle, the further selected airspeed value must be within the tilt angle-velocity envelope.

[0096] Subsequently, since the center of gravity should remain within a defined area throughout the flight, both forward and rearward shifts in the center of gravity will affect the aircraft's stability. Therefore, by using the tilt angle-velocity envelope, weight-center of gravity analysis data, and tilt downwash airflow analysis data, the tilt angle range where center of gravity changes drastically and / or attitude changes can be determined. This leads to the range where the aircraft's stability is prone to deterioration during rotor tilting, which is also the tilt angle range that requires focused testing—the first angle test range. For example, the longitudinal dynamic stability of the aircraft is usually poor under conditions such as high speed and heavy weight with a poor center of gravity and large tilt angles, low speed and heavy weight with a poor center of gravity position, and medium tilt angles. When these conditions are most affected by the downwash airflow disturbance, the corresponding test conditions will typically increase exponentially.

[0097] It should be understood that the aircraft stability verification equipment can also determine the tilt angle range with the most stable center of gravity and attitude changes by using the tilt angle-velocity envelope, weight and center of gravity analysis data, and tilt downwash airflow analysis data. This allows the aircraft to obtain the range in which its stability is clearly normal during rotor tilting, which is also the tilt angle range that does not require special testing, i.e., the second angle test range.

[0098] It should be understood that by collecting data on the changes in other parameters of the aircraft during rotor tilting, the tilting angle range in which the parameter changes are most drastic or most stable can be determined, such as altitude and rotor speed.

[0099] Step S220: According to the preset second quantity, increase the number of secondary test conditions under the primary test conditions within the first angle test range, where the preset second quantity is greater than the preset first quantity;

[0100] Specifically, after obtaining the first angle test range, in order to focus on testing the working conditions corresponding to the thrust vector angle or tilt mechanism actuation angle within this range, a second-level test condition can be added under the first-level test condition within this range. Specifically, by setting a preset second quantity greater than a preset first quantity, and then, based on the difference between the preset second quantity and the preset first quantity, under each first-level test condition within the first angle test range, by increasing the number of other test parameters of the aircraft within the testable range, the number of second-level test conditions under the first-level test condition is increased accordingly.

[0101] And / or step S230, according to a preset third quantity, reduce the number of secondary test conditions under the primary test conditions within the second angle test range, wherein the preset third quantity is less than the preset first quantity.

[0102] Specifically, after obtaining the second angle test range, in order to reduce test costs and time and improve the efficiency of testing the working conditions corresponding to the thrust vector angle or tilting mechanism actuation angle within this range, the number of secondary test conditions under the primary test conditions within this range can be reduced. Specifically, this is achieved by setting a preset third quantity that is less than a preset first quantity, and then, based on the difference between the preset third quantity and the preset first quantity, reducing the number of secondary test conditions accordingly under each primary test condition within the second angle test range.

[0103] Furthermore, the first-level test condition includes a second-level test condition, and after step A01, steps B01 to B03 are also included:

[0104] Step B01: Based on the flight envelope, weight and center of gravity analysis data, and tilt downwash airflow analysis data of the aircraft, determine at least one first angle test range and one second angle test range for the aircraft.

[0105] Step B02: Increase the number of Level 1 test conditions within the first angle test range;

[0106] Step B03, and / or, reduce the number of Level 1 test conditions within the second angle test range.

[0107] Specifically, the aircraft stability verification equipment can also increase or decrease the number of primary test conditions in different angle test ranges by increasing the sampling density in different angle test ranges.

[0108] For example, referring to the description of the above embodiments, at least one first angle test range and a second angle test range of the aircraft are determined based on the preset flight envelope, the weight and center of gravity analysis data of the aircraft, and the tilt downwash airflow analysis data.

[0109] Then, in the first angle test zone that requires key testing, the number of first-level test conditions in the first angle test zone is increased by reducing the angle interval used for division. This allows for a more comprehensive longitudinal dynamic stability test of the aircraft through a greater number of first-level test conditions, resulting in more accurate aircraft stability verification results.

[0110] Optionally, in the second angle test interval where no key test is required, the number of first-level test conditions in the first angle test interval can be reduced by increasing the angle intervals used for division or by reducing the number of original first-level test conditions, thereby improving the test efficiency of the aircraft's longitudinal dynamic stability.

[0111] This embodiment, through the above-described scheme, determines the key and non-key test zones of the aircraft based on the preset flight envelope, the weight and center of gravity analysis data of the aircraft, and the tilt-rotor downwash airflow analysis data. By increasing the number of secondary test zones for the primary test conditions within the key test zones and reducing the number of secondary test zones for the primary test conditions within the non-key test zones, the focus of the test conditions can be adjusted. This reduces unnecessary test conditions and improves the verification efficiency and accuracy of the longitudinal dynamic stability of the tiltrotor aircraft, thereby accurately determining the safety of the tiltrotor aircraft in terms of configuration and flight control design and improving the flight safety of the aircraft.

[0112] Based on the above embodiments of this application, in the third embodiment of this application, the same or similar content as the above embodiments can be referred to the above description, and will not be repeated hereafter. Based on this, please refer to... Figure 3 The stability verification result includes the longitudinal dynamic stability verification result. Step S130 includes steps S310 to S320:

[0113] Step S310: Determine the oscillation period and oscillation amplitude of the aircraft under longitudinal oscillation state based on the flight parameter data of the aircraft;

[0114] Specifically, based on the flight parameter data of the aircraft in a longitudinal oscillation state after the input disturbance, data analysis software can be used to fit the change curve of the aircraft's flight parameter values ​​with the disturbance time in the longitudinal oscillation state. Furthermore, based on the change curve, the oscillation period and oscillation amplitude of the aircraft's flight parameter values ​​with the disturbance time in the longitudinal oscillation state can be determined.

[0115] Among them, the oscillation period refers to the time required for an aircraft to complete one full oscillation in a longitudinal oscillation state; the oscillation amplitude refers to the maximum fluctuation of the flight parameters of an aircraft from its equilibrium position within a full oscillation period.

[0116] The method for obtaining the oscillation period from the change curve is not limited. It can be to further perform a fast Fourier transform or wavelet transform on the change curve to identify the peak frequency corresponding to different oscillation periods, and then obtain it by calculating the peak derivative.

[0117] Step S320: Based on the oscillation period and oscillation amplitude, confirm whether the aircraft meets the heavy damping characteristics, and obtain the longitudinal dynamic stability verification result of the aircraft under the test conditions.

[0118] It should be noted that the heavy damping characteristic in this application refers to the fact that after a disturbance is input to the aircraft, the oscillation amplitude of the aircraft's flight parameters decays to less than 1 / 10 of the initial amplitude within a set time. The set time is the time set by relevant personnel according to actual needs, and is usually 2 oscillation cycles.

[0119] Based on the oscillation period, confirm whether the oscillation amplitude of the flight parameters of the aircraft in the longitudinal oscillation state meets the change required by the heavy damping characteristics.

[0120] If the oscillation amplitude of the flight parameters of the aircraft in the longitudinal oscillation state meets the change required by the heavy damping characteristics, it can be considered that the tiltrotor aircraft has longitudinal dynamic stability under flight test conditions.

[0121] It should be understood that the aircraft test conditions selected in this application are discrete aircraft operating points. Therefore, if the tiltrotor aircraft has longitudinal dynamic stability under all the divided aircraft test conditions, it can be considered that the tiltrotor aircraft has longitudinal dynamic stability during the rotor tilting process.

[0122] This embodiment analyzes the flight parameter data of the aircraft to determine the oscillation period of the amplitude change of the flight parameters under longitudinal oscillation. Based on this oscillation period, it further determines the change in the oscillation amplitude of the flight parameters under longitudinal oscillation to meet the requirements of the heavy damping characteristics, thereby obtaining the stability verification results of the aircraft. By conducting tests and analyses on multiple aircraft test conditions to realize the longitudinal dynamic stability of the tiltrotor aircraft, the safety of the tiltrotor aircraft in configuration design and flight control design can be accurately determined, thereby improving the flight safety of the aircraft.

[0123] Based on the above embodiments of this application, in the fourth embodiment of this application, the same or similar content as the above embodiments can be referred to the above description, and will not be repeated hereafter. Based on this, please refer to... Figure 4 The disturbance includes a short-period longitudinal disturbance, the longitudinal oscillation state includes a short-period longitudinal oscillation state, and step S120 includes steps S410 to S420:

[0124] Step S410: When the aircraft is in the trimmed and stationary flight state, according to the pilot's first longitudinal control action, a short-period longitudinal disturbance in the form of a single pulse and / or a double pulse is input to the aircraft to make the aircraft be in a longitudinal short-period oscillation state, and the flight parameter data of the aircraft is collected.

[0125] It should be understood that longitudinal short-period oscillation refers to the damped oscillation state of an aircraft in the pitch plane at a short-period mode frequency. The longitudinal short-period oscillation of an aircraft typically involves a series of rapidly occurring changes in parameters such as pitch acceleration, pitch rate, and pitch attitude. Because these changes occur so rapidly, the change in flight speed is not significant. Furthermore, the angle of attack of the aircraft will change due to pitch motion, thus causing accompanying changes in normal acceleration.

[0126] Specifically, in order to apply short-period longitudinal disturbances to an aircraft, the aircraft can be inputted with short-period longitudinal disturbances by receiving instantaneous maneuvering and control actions performed by the pilot through the control stick, elevator, longitudinal controller, etc., i.e., the first longitudinal control action. This will induce the aircraft to perform short-period longitudinal oscillations and simultaneously record the complete flight parameter data of the aircraft in the short-period longitudinal oscillation state after the input disturbance, so as to subsequently evaluate the longitudinal dynamic stability of the aircraft.

[0127] Understandably, short-period longitudinal disturbances are essentially longitudinal control pulses, and the longitudinal control pulses that cause an aircraft to achieve a short-period oscillation state can be in the form of single pulses or double pulses. A double-pulse input disturbance causes the aircraft's pitch attitude to first deviate in one direction and then in the opposite direction. For example, a first longitudinal control action can be used to apply nose-down longitudinal control to the aircraft, causing a slight decrease in pitch attitude, followed by a reverse input of nose-up longitudinal control to restore the pitch attitude to a balanced state. A single-pulse input disturbance causes the aircraft's pitch attitude to deviate in one direction. For example, a first longitudinal control action can be used to apply nose-up or nose-down longitudinal control to the aircraft, producing changes in pitch rate, normal acceleration, and angle of attack.

[0128] Furthermore, when the aircraft uses the longitudinal controller to achieve short-cycle longitudinal disturbance, according to the first longitudinal control action, when the pitch attitude returns to the equilibrium position, the longitudinal controller is controlled to return to the equilibrium position and released, thereby triggering a short-cycle oscillation state without control; or the longitudinal controller is kept in the equilibrium position, thereby triggering a short-cycle oscillation state with fixed control.

[0129] For example, the first longitudinal control action can be a double-pulse input disturbance achieved by first applying a rear rudder stick input and then applying a front rudder stick input in the opposite direction, or it can be a single-pulse input disturbance achieved by applying longitudinal control with the nose pointing downwards.

[0130] Alternatively, in step S420, when the aircraft is in the trimmed, vertical flight state, a short-period longitudinal disturbance is input to the aircraft according to a preset first single-pulse signal and / or double-pulse signal to make the aircraft be in a longitudinal short-period oscillation state, and the flight parameter data of the aircraft is collected.

[0131] Referring to the above, multiple pre-set first single-pulse signals and first double-pulse signals can be used to generate short-period longitudinal disturbances in the form of single or double pulses, thereby triggering the aircraft to enter an uncontrolled short-period oscillation state or a fixed-controlled short-period oscillation state. Simultaneously, flight parameter data of the aircraft in the longitudinal short-period oscillation state after the input disturbance are collected for subsequent evaluation of the aircraft's longitudinal dynamic stability.

[0132] Furthermore, based on the scheme described in the above embodiments, after collecting flight parameter data showing that the aircraft is in a longitudinal short-period oscillation state after the input disturbance, it is necessary to further analyze whether the aircraft meets the heavy damping characteristics. Therefore, step S310 includes the following step S3101:

[0133] Step S3101: Determine the oscillation period and oscillation amplitude of the aircraft in the longitudinal short-period oscillation state based on the flight parameter data.

[0134] Specifically, based on the flight parameter data of the aircraft in a longitudinal short-period oscillation state after the input disturbance, the data analysis software is used to fit the change curve of the aircraft's flight parameter values ​​with the disturbance time in the longitudinal short-period oscillation state. Furthermore, based on the change curve, the oscillation period and oscillation amplitude of the aircraft's flight parameter values ​​with the disturbance time in the longitudinal short-period oscillation state are determined.

[0135] This embodiment, through the above-described scheme, specifically by inputting short-period longitudinal disturbances in the form of single pulses and / or double pulses to the aircraft based on the pilot's first longitudinal control action, or by using a preset first single pulse signal and / or double pulse signal, to put the aircraft into a longitudinal short-period oscillation state, thus achieving multiple input disturbance methods and increasing the testing flexibility of the aircraft's longitudinal dynamic stability; simultaneously, by collecting the aircraft's flight parameter data and further analyzing the flight parameter data, the stability verification results of the aircraft are obtained. By testing and analyzing the longitudinal dynamic stability of the tiltrotor aircraft under multiple test conditions, the safety of the tiltrotor aircraft in configuration design and flight control design can be accurately determined, thereby improving the aircraft's flight safety.

[0136] Based on the above embodiments of this application, in the fifth embodiment of this application, the same or similar content as the above embodiments can be referred to the above description, and will not be repeated hereafter. Based on this, please refer to... Figure 5 The disturbance further includes long-period longitudinal disturbances, and the longitudinal oscillation state further includes a long-period longitudinal oscillation state. Step S120 further includes steps S510 to S520:

[0137] Step S510: When the aircraft is in the trimmed and stationary flight state, according to the pilot's second longitudinal control action, a long-period longitudinal disturbance in the form of a single pulse is input to the aircraft to make the aircraft be in a long-period longitudinal oscillation state, and the flight parameter data of the aircraft are collected.

[0138] It should be understood that the longitudinal long-period oscillation state refers to the slow heave and velocity coupled oscillation of an aircraft in the pitch plane at a long-period mode frequency, which is manifested as large and relatively slow changes in parameters such as pitch attitude, flight speed and altitude.

[0139] Specifically, in order to apply long-period longitudinal disturbances to an aircraft, the aircraft can be input with long-period longitudinal disturbances by receiving instantaneous maneuvering and control actions performed by the pilot through the control stick, elevator, longitudinal controller, etc., i.e., the second longitudinal control action. This will induce the aircraft to perform long-period longitudinal oscillations and simultaneously record the complete flight parameter data of the aircraft in the long-period longitudinal oscillation state after the input disturbance, so as to evaluate the longitudinal dynamic stability of the aircraft in the future.

[0140] To test the longitudinal dynamic stability of an aircraft under long-period oscillation, it is usually necessary to deviate the aircraft's flight speed from the equilibrium speed by a significant amount, such as 10%, through elevator input. Then, the numerical oscillations of flight parameters such as airspeed, rate of climb and descent, altitude, and pitch attitude are allowed to occur naturally without any constraints on any variables, as long as the flight speed or other safety limits are not exceeded.

[0141] Understandably, long-period longitudinal disturbance is essentially a single-pulse longitudinal control pulse. Specifically, it can be achieved through a second longitudinal control action to create a relatively slow and long-lasting elevator pulse, causing the aircraft's speed to increase or decrease from the equilibrium point until it reaches the target where the speed deviates.

[0142] When an aircraft uses a longitudinal controller to implement long-period longitudinal disturbances, once the target velocity deviation is reached, the longitudinal controller should return to its initial position and be released.

[0143] Alternatively, in step S520, when the aircraft is in the trimmed and stationary flight state, a long-period longitudinal disturbance is input to the aircraft according to a preset second single pulse signal to make the aircraft be in a long-period longitudinal oscillation state, and the flight parameter data of the aircraft are collected.

[0144] Referring to the above, multiple pre-set second single-pulse signals can be used to generate a long-period longitudinal disturbance in the form of a single pulse, thereby triggering the aircraft to enter a long-period oscillation state. Simultaneously, flight parameter data of the aircraft in a long-period longitudinal oscillation state after the input disturbance are collected for subsequent evaluation of the aircraft's longitudinal dynamic stability.

[0145] Furthermore, based on the scheme described in the above embodiments, after collecting flight parameter data showing that the aircraft is in a longitudinal long-period oscillation state after the input disturbance, it is necessary to further analyze whether the aircraft meets the heavy damping characteristics. Therefore, step S310 includes the following step S3102:

[0146] Step S3102: Determine the oscillation period and amplitude of the aircraft in the longitudinal long-period oscillation state based on the flight parameter data.

[0147] Specifically, based on the flight parameter data of the aircraft in a longitudinal long-period oscillation state after the input disturbance, the data analysis software is used to fit the change curve of the aircraft's flight parameter values ​​with the disturbance time in the longitudinal long-period oscillation state. Furthermore, based on the change curve, the oscillation period and oscillation amplitude of the aircraft's flight parameter values ​​with the disturbance time in the longitudinal long-period oscillation state are determined.

[0148] This embodiment, through the above-described scheme, specifically by inputting long-period longitudinal disturbances in the form of single pulses to the aircraft based on the pilot's second longitudinal control action, or by implementing multiple input disturbance methods based on a preset second single pulse signal, increases the testing flexibility of the aircraft's longitudinal dynamic stability. Simultaneously, by collecting the aircraft's flight parameter data and further analyzing this data, the stability verification results of the aircraft are obtained. Through testing and analyzing the longitudinal dynamic stability of the tiltrotor aircraft under multiple test conditions, the safety of the tiltrotor aircraft's configuration and flight control design is accurately determined, thereby improving the aircraft's flight safety.

[0149] Based on the above embodiments of this application, in the sixth embodiment of this application, the same or similar content as the above embodiments can be referred to the above description, and will not be repeated hereafter. Based on this, step S3102 includes steps S610 to S620:

[0150] Step S610: Based on the flight parameter data of the aircraft, construct the envelope curve of the flight parameter offset value versus time under the longitudinal long-period oscillation state of the aircraft;

[0151] Step S620: Determine the oscillation period and oscillation amplitude of the aircraft in the longitudinal long-period oscillation state based on the envelope curve of the flight parameter offset value versus time.

[0152] It should be noted that the flight parameter offset value refers to the instantaneous deviation of each flight parameter from the trim reference value in the initial trimmed, straight-line flight state.

[0153] Specifically, firstly, based on the flight parameter data of the aircraft in a longitudinal long-period oscillation state after the input disturbance, the time-series variation curve of each flight parameter offset value is obtained. Then, peak analysis is performed on the time-series variation curve of the offset value to construct the envelope curve of the maximum and minimum offset values ​​of the flight parameters changing with the disturbance time under the longitudinal long-period oscillation state.

[0154] Then, based on the envelope curve of the flight parameter offset value versus time, the time when the flight parameter oscillation amplitude of the aircraft doubles is determined, and thus the oscillation period of the corresponding flight parameter is determined.

[0155] It should be understood that the oscillation period obtained when the aircraft is in a longitudinal short-period oscillation state can be the first oscillation period; the oscillation period obtained when the aircraft is in a longitudinal long-period oscillation state can be the second oscillation period.

[0156] Based on the first oscillation period, confirm whether the oscillation amplitude of the flight parameters of the aircraft in the longitudinal short-period oscillation state meets the change required by the heavy damping characteristic; based on the second oscillation period, confirm whether the oscillation amplitude of the flight parameters of the aircraft in the longitudinal long-period oscillation state meets the change required by the heavy damping characteristic.

[0157] When the oscillation amplitude of the flight parameters of the aircraft in the longitudinal short-period oscillation state meets the change required by the heavy damping characteristic, and the oscillation amplitude of the flight parameters of the aircraft in the longitudinal long-period oscillation state meets the change required by the heavy damping characteristic, it can be considered that the tiltrotor aircraft has longitudinal dynamic stability under the flight test conditions.

[0158] This embodiment analyzes the flight parameter data of an aircraft in a longitudinal long-period oscillation state after input disturbance. By constructing the envelope curve of flight parameter offset value versus time, the oscillation period and amplitude of the aircraft in the longitudinal long-period oscillation state are determined. Furthermore, based on the oscillation period, the oscillation amplitude of the flight parameters in the longitudinal long-period oscillation state is determined to meet the change required by the heavy damping characteristics, thereby obtaining the stability verification results of the aircraft. Through the test and analysis of the longitudinal dynamic stability of the tiltrotor aircraft under multiple test conditions, the safety of the tiltrotor aircraft in configuration design and flight control design is accurately determined, thereby improving the flight safety of the aircraft.

[0159] The above description is only a part of the embodiments of this application and does not limit the patent scope of this application. All equivalent structural transformations made under the technical concept of this application and using the contents of the specification and drawings of this application, or direct / indirect applications in other related technical fields, are included in the patent protection scope of this application.

Claims

1. A method for verifying the stability of an aircraft, characterized in that, The aircraft stability verification method is applied to tiltrotor aircraft, and the aircraft stability verification method includes: Based on the test conditions of the aircraft, the straight flight state of the aircraft after trim is established. The test conditions of the aircraft are obtained by dividing the thrust vector angle or the tilt mechanism actuation angle. When the aircraft is in the trimmed, upright flight state, a disturbance is input to the aircraft to make it oscillate longitudinally, and the flight parameter data of the aircraft is collected. Based on the flight parameter data of the aircraft, the stability verification results of the aircraft under the test conditions are determined.

2. The aircraft stability verification method as described in claim 1, characterized in that, The aircraft test conditions include a first-level test condition. Before the step of establishing the trimmed, stationary flight state of the aircraft based on the aircraft test conditions, the following steps are included: According to the preset angle interval, the thrust vector angle or tilting mechanism actuation angle of the preset test range is divided to obtain several first-level test conditions.

3. The aircraft stability verification method as described in claim 2, characterized in that, The first-level test condition includes a second-level test condition. Following the step of dividing the thrust vector angle or tilting mechanism actuation angle of a preset test interval according to a preset angle interval to obtain several first-level test conditions, the following steps are included: Based on the preset first quantity and the first-level test conditions, a number of the second-level test conditions are determined.

4. The aircraft stability verification method as described in claim 2, characterized in that, The first-level test condition includes a second-level test condition. Following the step of dividing the thrust vector angle or tilting mechanism actuation angle of a preset test interval according to a preset angle interval to obtain several first-level test conditions, the following steps are included: Based on the flight envelope, weight and center of gravity analysis data of the aircraft, and tilt downwash airflow analysis data, at least one first angle test range and one second angle test range of the aircraft are determined. Increase the number of Level 1 test conditions within the first angle test range; And / or, reduce the number of Level 1 test conditions within the second angle test range.

5. The aircraft stability verification method as described in claim 3, characterized in that, After the step of determining a number of secondary test conditions based on a preset first quantity and the primary test conditions, the method further includes: Based on the flight envelope, weight and center of gravity analysis data of the aircraft, and tilt downwash airflow analysis data, at least one first angle test range and one second angle test range of the aircraft are determined. Based on a preset second quantity, the number of secondary test conditions under the primary test condition within the first angle test range is increased, wherein the preset second quantity is greater than the preset first quantity; and / or According to the preset third quantity, the number of secondary test conditions under the primary test conditions within the second angle test range is reduced, and the preset third quantity is less than the preset first quantity.

6. The aircraft stability verification method as described in claim 1, characterized in that, The step of establishing the trimmed, stable flight state of the aircraft based on the aircraft test conditions includes: Based on the test conditions of the aircraft, determine the corresponding thrust vector angle or tilt mechanism actuation angle; The aircraft is trimmed to establish a stationary flight state after trimming at the thrust vector angle or tilt mechanism actuation angle.

7. The aircraft stability verification method as described in claim 1, characterized in that, The stability verification results include longitudinal dynamic stability verification results. The step of determining the stability verification results of the aircraft under the test conditions based on the aircraft's flight parameter data includes: Based on the flight parameter data of the aircraft, determine the oscillation period and oscillation amplitude of the aircraft under longitudinal oscillation conditions; Based on the oscillation period and oscillation amplitude, it is confirmed whether the aircraft meets the heavy damping characteristics, and the longitudinal dynamic stability verification result of the aircraft under the test conditions is obtained.

8. The aircraft stability verification method as described in claim 7, characterized in that, The disturbance includes a short-period longitudinal disturbance, the longitudinal oscillation state includes a short-period longitudinal oscillation state, and the method further includes: Based on the pilot's first longitudinal control action, a short-period longitudinal disturbance in the form of a single pulse and / or a double pulse is input to the aircraft to put the aircraft into a short-period longitudinal oscillation state, and flight parameter data of the aircraft is collected. The oscillation period and amplitude of the aircraft in the short-period longitudinal oscillation state are determined based on the flight parameter data; or Based on a preset first single-pulse signal and / or double-pulse signal, a short-period longitudinal disturbance is input to the aircraft to make the aircraft put into a longitudinal short-period oscillation state, and the flight parameter data of the aircraft is collected. Based on the flight parameter data, the oscillation period and oscillation amplitude of the aircraft in the longitudinal short-period oscillation state are determined.

9. The aircraft stability verification method as described in claim 8, characterized in that, The disturbance also includes a long-period longitudinal disturbance, and the longitudinal oscillation state also includes a long-period longitudinal oscillation state. The method further includes: Based on the pilot's second longitudinal control action, a long-period longitudinal disturbance in the form of a single pulse is input to the aircraft to put it into a long-period longitudinal oscillation state. Flight parameter data of the aircraft is collected, and the oscillation period and amplitude of the aircraft in the long-period longitudinal oscillation state are determined based on the flight parameter data; or According to the preset second single pulse signal, a long-period longitudinal disturbance is input to the aircraft to make the aircraft put into a long-period longitudinal oscillation state, and the flight parameter data of the aircraft is collected. Based on the flight parameter data, the oscillation period and oscillation amplitude of the aircraft in the long-period longitudinal oscillation state are determined.

10. The aircraft stability verification method as described in claim 9, characterized in that, The step of determining the oscillation period and amplitude of the aircraft in a longitudinal long-period oscillation state based on flight parameter data includes: Based on the flight parameter data of the aircraft, construct the envelope curve of the flight parameter offset value versus time under the longitudinal long-period oscillation state of the aircraft; Based on the envelope curve of the flight parameter offset value versus time, the oscillation period and oscillation amplitude of the aircraft in the longitudinal long-period oscillation state are determined.

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