A method for suppressing false alarms in FOQA monitoring

Abstract

This invention provides a method for suppressing false alarms in FOQA monitoring. The method includes: (1) calculating the takeoff and landing times; (2) calculating the average taxiing direction during takeoff and landing; (3) calculating the lateral movement distance per second before takeoff and after landing using the differential method; (4) summing the lateral movement distances per second to obtain the lateral distance relative to the runway at each moment; and (5) using the lateral movement distance to suppress false alarms in FOQA. This invention uses QAR data to calculate the lateral distance of the aircraft relative to the runway during takeoff and landing, effectively avoiding the false alarm problem that ground operation items in traditional FOQA alarm logic are prone to cause due to boundary condition settings, airport requirements, and other factors, and strongly supports flight data analysis work such as FOQA monitoring.

Description

Technical Field

[0001] This invention relates to the field of flight data analysis, and in particular to a method for suppressing false alarms in FOQA monitoring. Background Technology

[0002] Flight Quality Assurance (FOQA) is an internationally recognized and crucial means of ensuring flight safety, widely accepted by the global civil aviation industry. International civil aviation conventions stipulate that operators of aircraft with a maximum certified takeoff weight exceeding 27,000 kg should develop and implement a FOQA program as part of their safety management system. It is also recommended that operators of aircraft with a certified takeoff weight exceeding 20,000 kg develop and implement a FOQA program.

[0003] To improve aviation safety, the Civil Aviation Administration of China (CAAC) implemented a flight quality monitoring program for all air transport carriers starting in 1997, and issued Airworthiness Directive CAD1997-MULT-38, stipulating that from January 1, 1998, all transport aircraft registered and operating in China must be equipped with Quick Access Recorders (QARs) or equivalent equipment. On December 15, 2000, the CAAC Aviation Safety Office issued the "Regulations on the Management of Flight Quality Monitoring Work," which set forth work requirements in three aspects: "equipment and monitoring requirements," "organizational setup and personnel," and "operation," thus standardizing flight quality monitoring work. On January 4, 2010, the Civil Aviation Administration of China (CAAC) issued the "Rules for the Qualification Assessment of Large Aircraft Public Air Transport Carriers" (CCAR-121-R4), which formally established requirements for flight quality monitoring in the form of regulations.

[0004] The value of flight quality monitoring lies in identifying potential safety hazards such as non-compliant operations, defective procedures, aircraft performance degradation, and imperfections in air traffic control systems as early as possible by monitoring flight parameter exceedances. This provides data and information support for the formulation and implementation of improvement measures. However, during flight quality monitoring, false alarms have consistently plagued monitoring personnel due to issues with the data itself and unreasonable monitoring threshold and logic settings. In particular, alarms related to ground operations have always been a major source of false alarms.

[0005] Taking an airline's FOQA monitoring items as an example, these include ground operation items such as "excessive straight-line taxiing speed" and "excessive turning speed." Because existing procedures cannot accurately determine whether the aircraft is on the runway, i.e., its position relative to the runway, the aircraft is highly likely to trigger the "excessive straight-line taxiing speed" alarm during takeoff. During landing, because air traffic control often requires pilots to leave the runway area as quickly as possible, false alarms related to ground operation items are also easily triggered. Therefore, in summary, when performing FOQA work, it is necessary to conditionally suppress certain alarm items triggered by the aircraft on the airport runway. The suppression and non-suppression phases are as follows: Figure 2 As shown. Summary of the Invention

[0006] The purpose of this invention is to provide a method for calculating the lateral distance of an aircraft from the runway when it is on the ground, in order to address the problems existing in current FOQA monitoring technology and solve the problem that false alarms are prone to occur in existing ground monitoring items.

[0007] The objective of this invention is achieved through the following technical solution:

[0008] A method for suppressing false alarms in FOQA monitoring, the method comprising the following steps:

[0009] (1) Calculate the takeoff and landing times;

[0010] (2) Calculate the average taxiing direction during takeoff and landing;

[0011] (3) Use the differential method to calculate the lateral movement distance per second before takeoff and after landing;

[0012] (4) Sum the lateral movement distances per second to obtain the lateral distance relative to the runway at each moment;

[0013] (5) Use lateral movement distance to suppress false alarms in FOQA.

[0014] As a further technical solution, the specific content of step (1) is as follows:

[0015] (1.1) Acquire landing gear wheel load signal data;

[0016] (1.2) Calculate the first moment when the landing gear wheel load signal changes from loaded to unloaded, and take it as the aircraft takeoff point;

[0017] (1.3) Calculate the last moment when the landing gear wheel load signal changes from no load to load, and take it as the aircraft landing point.

[0018] As a further technical solution, the specific content of step (2) is as follows:

[0019] (2.1) Let the aircraft magnetic heading data be set E. Reorganize the data in E, and let... All have a∈R 360 R 360 A 360° ring;

[0020] (2.2) Obtain the magnetic heading data subset E from E, which is from several seconds before the takeoff point to the takeoff time. T ={θ1,θ2,…,θ n-1 ,θ n}, where θ n Magnetic heading at takeoff;

[0021] (2.3) Calculate θ1, θ2, ..., θ on the ring. n-1 to θ n The difference, and take the mean θ aver , then θ aver With θ n Adding them together, we get the average takeoff direction θ at the moment of takeoff. 起 ,Right now:

[0022]

[0023] It should be noted that both addition and subtraction occur within the ring R. 360 Operations on.

[0024] (2.4) Similarly, a subset of magnetic heading data from the landing moment to several seconds after landing is obtained, and the average taxiing direction θ at the landing moment is calculated using the same algorithm as in (2.3). 降 .

[0025] As a further technical solution, the specific content of step (3) is as follows:

[0026] (3.1) Find the differential. Let the ground velocity of the aircraft at time t after landing be v. t The angle is θ t The ground speed at t+1 is v t+1 The angle is θ t+1 Divide the aircraft's ground speed and angle from time t to t+1 into n parts, where n ≥ 1000. The data of the i-th derivative represents the data of the i-th derivative. Data at time t; the i-th ground velocity data value from time t to t+1. for:

[0027]

[0028] Similarly, the value of the i-th angle data from time t to t+1 is:

[0029]

[0030] (3.2) Consider the moving distance as the hypotenuse and the lateral moving distance as the opposite side. Let the first... The lateral movement distance at time x i Then we have:

[0031]

[0032] (3.3) x during the time interval from t to t+1 i Summing these values ​​gives the horizontal displacement of the aircraft from time t to t+1.

[0033]

[0034] (3.4) The same algorithm is used to calculate the lateral movement distance before takeoff. It is worth noting that the data before takeoff is in reverse order.

[0035] As a further technical solution, the specific content of step (5) is as follows:

[0036] (5.1) Obtain all alarms generated by ground operation monitoring items in the FOQA monitoring items;

[0037] (5.2) Obtain the runway width based on the airport classification;

[0038] (5.3) If at the time the alarm is generated, the lateral distance between the aircraft and the runway is less than the runway width, it means that the aircraft is on the runway at this time. It may be a false alarm generated during takeoff or landing, so it should be suppressed.

[0039] Compared with existing technologies, this invention uses on-ring addition, subtraction and differentiation algorithms to calculate the lateral distance between the aircraft and the runway, thereby improving the accuracy of FOQA alarm monitoring. Attached Figure Description

[0040] Figure 1 This is a flowchart of the FOQA monitoring and false alarm suppression process of the present invention;

[0041] Figure 2 Example diagram of FOQA monitoring;

[0042] Figure 3 A schematic diagram of the geometric principles used in the calculation.

[0043] Figure 4 The result is shown in the graph. Detailed Implementation

[0044] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0045] This embodiment uses data from a certain flight segment of a certain type of aircraft as an example to provide a method for suppressing false alarms in FOQA monitoring. This method can be applied in the field of FOQA alarm monitoring. The specific process of this method is as follows: Figure 1 As shown, it includes:

[0046] Step 1: Calculate takeoff and landing times: After QAR data is automatically downloaded via the WQAR module, it is automatically stored on the airline's configured server and decoded into structured data by flight data analysis software. The specific steps are as follows:

[0047] Step 1.1: Acquire landing gear wheel load signal data. The specific names of the landing gear wheel load signal data in the flight data analysis software can be found in the flight data parameter table. Therefore, the landing gear wheel load signal data can be obtained through the data interface.

[0048] Step 1.2: Calculate the first moment when the landing gear wheel load signal changes from loaded to unloaded as the aircraft takeoff point: The landing gear wheel load signal indicates whether there is a load on the aircraft landing gear. If there is a load, it means that the aircraft is on the ground. Therefore, the first moment when the signal changes from loaded to unloaded is the aircraft takeoff time.

[0049] Step 1.3: Similarly, calculate the last moment when the landing gear wheel load signal changes from no load to load, and use this as the aircraft landing point.

[0050] Step 2: Calculate the average takeoff and landing direction. The specific steps are as follows:

[0051] Step 2.1: Reshape the aircraft magnetic heading data, making... All have a∈R 360 R 360 This is a modulo 360 loop. Magnetic heading data records the aircraft's orientation at every moment. Obviously, its data value ranges from 0° to 360°. However, in actual operation, the magnetic heading data recorded for this type of aircraft is represented in a format of -180° to +180°. Therefore, it is necessary to add 180° to the value at each moment to reshape the data into a modulo 360 loop R. 360 .

[0052] Step 2.2: Obtain a subset of magnetic heading data from several seconds before takeoff to the moment of takeoff. The magnetic heading data for this aircraft type is recorded once per second, and the runway orientation at the takeoff airport is 1°. Due to factors such as operation and wind speed, the angle may slightly deviate during takeoff. The obtained subset of data is as follows: 1.05, 0.63, 1.21, 0.77, 1.02, 0.52, 359.86, 0.63. Here, 0.63 represents the magnetic heading at the moment of takeoff.

[0053] Step 2.3: Subtract from the loop to obtain the differences between each time before takeoff and the takeoff time: 0.42, 0, 0.58, 0.14, 0.39, -0.11, -0.76. Calculate the mean of the deviation, which is 0.094. Add this to the 0.63 at the takeoff time to obtain the average direction of the takeoff time as 0.724°, which is relatively close to the actual runway orientation of the takeoff airport.

[0054] Step 2.4: Similarly, obtain a subset of magnetic heading data from the landing time to a few seconds after landing. Using the same algorithm in Step 2.3, the average taxiing direction at landing is obtained as 110.21°, which is not much different from the actual runway orientation of 110°.

[0055] Step 3: Calculate the lateral movement distance per second before takeoff and after landing using the differential method. Taking a certain second after the aircraft leaves the runway and turns towards the parking position as an example, the specific steps are as follows:

[0056] Step 3.1: Calculate the differential. Based on the obtained ground speed and heading data, the ground speed is 15 knots at this moment and 12 knots in the next second; the aircraft's heading is 248.38° at this moment and 265.08° in the next second. Divide the entire process into 1000 parts. At the 100th moment, the angle is:

[0057] 248.38 + (100 / 1000) * (265.08 - 248.38) = 250.05°

[0058] The speed is:

[0059] 15 + (100 / 1000) * (12 - 15) = 14.7 sections.

[0060] Step 3.2: Consider the moving distance as the hypotenuse and the lateral moving distance as the opposite side. The value of the lateral moving distance is the moving distance multiplied by the sine of the angle between the aircraft's orientation and the runway direction. The geometric principle is as follows: Figure 3 As shown, the detailed results of the calculation method for the lateral movement distance of the aircraft in the 100th infinitesimal element are as follows:

[0061] The difference between the aircraft's orientation and the runway orientation at the time of landing is: 250.05° - 110.21° = 139.84°;

[0062] In that one-thousandth of a second, the distance the aircraft traveled was 14.7 knots * 0.5144 * 0.001 = 0.00756168 meters;

[0063] Therefore, the lateral distance the aircraft moves relative to the runway in this fraction of a second is: 0.00756168 * sin(139.84 / 180) = 0.00487671 meters.

[0064] Step 3.3: Sum the lateral movement distances of all infinitesimal elements to obtain the lateral movement distance of the aircraft in this second as 7.4773449 meters.

[0065] Step 3.4: Calculate the lateral movement distance before takeoff using the same algorithm. The movement distance after landing is calculated by accumulating the data second by second, while the movement distance before takeoff is calculated by accumulating the data second by second. Therefore, the data needs to be calculated in reverse order.

[0066] Step 4: Sum the lateral movement distances per second to obtain the lateral distance relative to the runway at each moment. In this flight segment data, the distance data to the runway is as follows: Figure 4 As shown.

[0067] Step 5: Use lateral movement distance to suppress false alarms in FOQA. Taking the above flight segment as an example, the specific steps are as follows:

[0068] Step 5.1: Obtain all alarms generated by ground operation monitoring items in the FOQA monitoring items. During this flight segment, one alarm was generated for excessive ground taxiing turning speed.

[0069] Step 5.2: Obtain the runway width based on the airport classification. This airport is a 4C-class airport with a runway width of 55 meters.

[0070] Step 5.3: At the time the alarm was generated, the lateral distance between the aircraft and the runway was 10.45269 meters, which is less than half the runway width. This indicates that the aircraft was on the runway at that time. After analysis, it was determined that the alarm was generated because the pilot followed the tower instructions to taxi off the runway as soon as possible. Therefore, it was suppressed.

[0071] This invention proposes a method for calculating the critical data of the lateral distance between the aircraft and the runway, which can effectively distinguish the position of the aircraft on and off the runway, thereby suppressing false alarms in FOQA and effectively improving the accuracy of FOQA operations.

[0072] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. It should be noted that any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for suppressing false alarms in FOQA monitoring, characterized in that, The method includes the following steps: (1) Calculate the takeoff and landing times; (2) Calculate the average takeoff and landing direction. The specific steps are as follows: Let the aircraft magnetic heading data be set E. Reorganize the data in E, and let... All have a∈R 360 R 360 A 360° ring; Obtain the magnetic heading data subset E from E, which is the data from several seconds before takeoff to the moment of takeoff. T ={θ1,θ2,…,θ n-1 ,θ n }, where θ n Magnetic heading at takeoff; Calculate θ1, θ2, ..., θ on the ring. n-1 to θ n The difference, and take the mean θ aver , then θ aver With θ n Adding them together, we get the average takeoff direction θ at the moment of takeoff. 起 ,Right now: It should be noted that both addition and subtraction occur within the ring R. 360 Operations on; Similarly, by acquiring a subset of magnetic heading data from the moment of landing to several seconds after landing, and using the same algorithm, the average taxiing direction θ at the moment of landing is calculated. 降 ; (3) Calculate the lateral movement distance per second before takeoff and after landing using the differential method. The specific steps are: find the differential, and let the ground speed of the aircraft at time t after landing be v. t The angle is θ t The ground speed at t+1 is v t+1 The angle is θ t+1 Divide the aircraft's ground speed and angle from time t to t+1 into n parts, where n ≥ 1000. The data of the i-th derivative represents the data of the i-th derivative. Data at time t; the i-th ground velocity data value from time t to t+1. for: Similarly, the value of the i-th angle data from time t to t+1 is: Consider the moving distance as the hypotenuse and the lateral moving distance as the opposite side. Let the first... The lateral movement distance at time x i Then we have: x during the time interval from t to t+1 i Summing these values, we obtain the horizontal displacement of the aircraft from time t to t+1: The same algorithm is used to calculate the lateral movement distance before takeoff. It is worth noting that the data before takeoff is in reverse order. (4) Sum the lateral movement distances per second to obtain the lateral distance relative to the runway at each moment; (5) Use lateral movement distance to suppress false alarms in FOQA.

2. The FOQA monitoring false alarm suppression method according to claim 1, characterized in that, The specific steps for calculating the takeoff and landing times in step (1) include: (2.1) Acquire landing gear wheel load signal data; (2.2) Calculate the first moment when the landing gear wheel load signal changes from loaded to unloaded, and take it as the aircraft takeoff point; (2.3) Calculate the last moment when the landing gear wheel load signal changes from no load to load, and take it as the aircraft landing point.

3. The FOQA monitoring false alarm suppression method according to claim 1, characterized in that, The specific steps for suppressing false alarms in FOQA using lateral movement distance in step (5) include: (3.1) Obtain all alarms generated by ground operation monitoring items in the FOQA monitoring items; (3.2) Obtain the runway width based on the airport classification; (3.3) If at the time the alarm is generated, the lateral distance between the aircraft and the runway is less than the runway width, it means that the aircraft is on the runway at this time. It may be a false alarm generated during takeoff or landing, so it should be suppressed.

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