Method for determining maintenance task and interval in airplane system / power device analysis process

Abstract

The invention provides a method for determining maintenance tasks and intervals in an airplane system / power device analysis process, which comprises the following steps of: extracting function failure data related to a system / power device to be analyzed from a database, and judging whether the airplane function failure affects the airplane safety or not by utilizing the data; judging whether the airplane function failure directly has negative effects on airplane operation or airplane task execution or not; actual operation data of the airplane are collected and analyzed, a dual-parameter Weibull distribution model is used for fitting fault data, and according to a model prediction result, a maintenance interval obtained through analysis is adjusted; and evaluating the maintenance task type and the maintenance interval of the system / power device. According to the method, the logic of an existing analysis method of the system / power device can be perfected, so that the logic better conforms to the design operation characteristics of the system / power device, meanwhile, the influence of subjective factors and the project development stage in the analysis process is avoided, and therefore the applicability and effectiveness of planned maintenance tasks are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of aircraft maintenance engineering, and in particular to a method for determining maintenance tasks and intervals during an aircraft system / power plant analysis process. Background Art

[0002] The mainstream civil aircraft manufacturers and operators in the world all use the MSG-3 (Maintenance Steering Group, MSG) analysis method based on reliability as the logical decision-making idea to formulate the planned maintenance outline of the aircraft. The purpose of this outline is to ensure the inherent safety and reliability of the aircraft design during the operation of the aircraft, and also to provide reasonable suggestions for the design optimization or modification of the aircraft. In view of the different components of the aircraft, the Air Transport Association of American (ATA) has developed four analysis methods, corresponding to the system / power unit part, regional part, structural part and lightning / high energy radiation field (L / HIRF) part of the aircraft.

[0003] In the actual work process, the analysis work of the system / power unit part is more likely to produce differences of opinion than the analysis work of the other three parts. First, the understanding of its analysis logic depends partly on the analyst's professional experience, and different engineering and technical personnel may formulate completely different planned maintenance tasks. In addition, the current system / power unit MSG-3 analysis logic does not take into account the special operating environment of the aircraft and the characteristics of the mission. Finally, the maintenance interval data in the initial planned maintenance tasks formulated by engineering analysts mainly comes from the design source data. This data is generally experimental data, and direct use may have a significant impact on economic efficiency. Affected by the above three aspects, the planned maintenance tasks formulated may be unreasonable, which will not only directly increase the operating cost of the aircraft, but also increase the workload of engineering analysts, and even affect the review progress of the maintenance review committee of the authority. Summary of the invention

[0004] In order to solve the above-mentioned problems existing in the prior art, the purpose of the present invention is to provide a method for determining maintenance tasks and intervals during the aircraft system / power unit analysis process, which method can not only improve the logic of the current analysis method of the system / power unit to make it more in line with the design and operation characteristics of the aircraft system / power unit, but also help to avoid the influence of subjective factors and project development stages in the analysis process, thereby improving the applicability and effectiveness of planned maintenance tasks.

[0005] The present invention achieves the above-mentioned purpose through the following technical solutions:

[0006] A method for determining maintenance tasks and intervals during aircraft system / power plant analysis, the method comprising the following steps:

[0007] Step S1, establishing a database, extracting functional failure data related to the system / power unit to be analyzed from the database, and using the data to determine whether the aircraft functional failure affects the aircraft safety;

[0008] Step S2, determining whether the aircraft function failure directly has a negative impact on the aircraft operability or the aircraft's mission execution;

[0009] Step S3, collecting and analyzing the actual operation data of the aircraft, applying a two-parameter Weibull distribution model to fit the fault data, and adjusting the maintenance interval obtained by the analysis according to the model prediction results;

[0010] Step S4, evaluating the system / power unit maintenance task type and maintenance interval.

[0011] According to a method for determining maintenance tasks and intervals during an aircraft system / power unit analysis process provided by the present invention, in step S1, a database includes functional failure data that has an impact on aircraft safety and functional failure data of historical aviation unsafe events analyzed during the aircraft design phase.

[0012] According to a method for determining maintenance tasks and intervals during an aircraft system / power unit analysis process provided by the present invention, when determining whether an aircraft function failure affects the aircraft safety, a detailed analysis is performed on the collected data to identify functional failure modes that have a potential impact on the aircraft safety, and a risk assessment tool is used to quantitatively evaluate the identified functional failures to determine the specific degree of impact on the aircraft safety.

[0013] According to a method for determining maintenance tasks and intervals during an aircraft system / power plant analysis process provided by the present invention, step S2 specifically includes:

[0014] Clarify the type of mission, mission requirements and mission environment that the aircraft needs to perform, so as to more accurately assess the impact of functional failure on mission execution;

[0015] For each potential functional failure mode, analyze its specific impact on the aircraft's operability and mission performance, including the severity of the impact, probability of occurrence, and ease of detection;

[0016] Risk assessment tools are used to quantify the impact of functional failures and determine their specific risk level to aircraft operability and mission performance.

[0017] According to a method for determining maintenance tasks and intervals during an aircraft system / power plant analysis process provided by the present invention, step S3 comprises:

[0018] Step S3-1, collecting maintenance task data, including data of planned maintenance tasks and unplanned maintenance tasks;

[0019] Step S3-2, using a two-parameter Weibull distribution maximum likelihood estimation method to determine a shape parameter β and a scale parameter η of the two-parameter Weibull distribution;

[0020] Step S3-3, according to the upper limits of the failure rates defined for different failure types, combined with the obtained parameters of the two-parameter Weibull distribution, the optimal maintenance interval is obtained.

[0021] According to a method for determining maintenance tasks and intervals during aircraft system / power plant analysis provided by the present invention, in step S3-2, the cumulative distribution function of the two-parameter Weibull distribution is expressed as the following formula:

[0022]

[0023] According to a method for determining maintenance tasks and intervals during aircraft system / power plant analysis provided by the present invention, in step S3-2, the probability density function of the two-parameter Weibull distribution is expressed as the following formula:

[0024]

[0025] Among them, the shape parameter β determines the shape of the cumulative distribution function, and the scale parameter η determines the degree of expansion and contraction of the cumulative distribution function in the horizontal direction.

[0026] According to a method for determining maintenance tasks and intervals during aircraft system / power plant analysis provided by the present invention, in step S3-2, the dual-parameter Weibull distribution maximum likelihood estimation function is expressed as the following formula:

[0027]

[0028] According to a method for determining maintenance tasks and intervals in an aircraft system / power unit analysis process provided by the present invention, in step S3-2, using the maintenance task data collected in step S3-1, Computes the shape parameter β and scale parameter η of the two-parameter Weibull distribution.

[0029] According to a method for determining maintenance tasks and intervals during aircraft system / power unit analysis provided by the present invention, in step S3-3, the optimal maintenance interval is solved based on the failure rates of different failure types combined with the obtained cumulative distribution function.

[0030] It can be seen that the present invention has the following beneficial effects:

[0031] 1. The present invention establishes a database and extracts relevant functional failure data. This method can use a large amount of actual data to support analysis, making the judgment more scientific and objective.

[0032] 2. The present invention adopts a dual-parameter Weibull distribution model to fit the fault data, which can more accurately describe the failure law of the equipment, thereby improving the reliability of the prediction results.

[0033] 3. The present invention not only focuses on the impact of functional failure on aircraft safety, but also comprehensively considers the direct impact of functional failure on aircraft operability and mission execution capability, ensuring the comprehensiveness of the analysis.

[0034] 4. The present invention comprehensively evaluates the maintenance task type and maintenance interval from the perspective of the system / power unit as a whole, which helps to formulate a more reasonable maintenance plan.

[0035] 5. According to the prediction results of the model, the present invention can dynamically adjust the maintenance interval obtained by analysis to adapt to changes in the actual operating status of the equipment.

[0036] 6. The present invention can effectively control maintenance costs and improve economic benefits while ensuring equipment safety through scientific and reasonable maintenance tasks and interval settings.

[0037] 7. The present invention can reduce unnecessary maintenance activities, improve the availability and operating efficiency of equipment, and provide strong support for the operation of airlines.

[0038] 8. The present invention clarifies the standardized process from database establishment, data extraction, failure judgment, operation data analysis to maintenance tasks and interval evaluation, which helps to improve work efficiency and reduce human errors.

[0039] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 The present invention is a flowchart of an embodiment of a method for determining maintenance tasks and intervals during an aircraft system / power plant analysis process.

[0041] Figure 2 The present invention is a logic flow chart of how to determine maintenance tasks and intervals in an embodiment of a method for determining maintenance tasks and intervals during an aircraft system / power unit analysis process.

[0042] Figure 3 The present invention is a flowchart for solving the optimal maintenance interval in an embodiment of a method for determining maintenance tasks and intervals during an aircraft system / power unit analysis process. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0044] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0045] See also Figures 1 to 3 The present invention provides a method for determining maintenance tasks and intervals during aircraft system / power plant analysis, the method comprising the following steps:

[0046] Step S1, establishing a database, extracting functional failure data related to the system / power unit to be analyzed from the database, and using the data to determine whether the aircraft functional failure affects the aircraft safety;

[0047] Step S2, determining whether the aircraft function failure directly has a negative impact on the aircraft operability or the aircraft's mission execution;

[0048] Step S3, collecting and analyzing the actual operation data of the aircraft, applying a two-parameter Weibull distribution model to fit the fault data, and adjusting the maintenance interval obtained by the analysis according to the model prediction results;

[0049] Step S4, evaluating the system / power unit maintenance task type and maintenance interval.

[0050] According to a method for determining maintenance tasks and intervals during an aircraft system / power unit analysis process provided by the present invention, in step S1, the database includes functional failure data that have an impact on aircraft safety and functional failure data of historical aviation unsafe events analyzed during the aircraft design phase, as shown in Table (1).

[0051]

[0052] In this embodiment, when determining whether an aircraft functional failure affects the safety of the aircraft, the collected data is analyzed in detail to identify functional failure modes that have potential impacts on the safety of the aircraft, and a risk assessment tool is used to quantitatively evaluate the identified functional failures to determine their specific impact on the safety of the aircraft.

[0053] Furthermore, during the aircraft design phase, engineers and designers will conduct detailed failure mode and effects analysis (FMEA), fault tree analysis (FTA), etc. to identify potential functional failure modes and assess the potential impact of these failures on aircraft safety. These analysis results will be recorded in the database as an important reference for subsequent maintenance task analysis and interval determination.

[0054] Furthermore, in addition to the analysis results of the design phase, the database will also contain data on actual aviation unsafe events that have occurred over the years. These events may include accidents, serious accident signs, general accident signs, and unplanned maintenance events, etc., which are usually directly related to specific functional failures. By analyzing the causes, consequences, and corrective measures taken by these events, the analysis results of the design phase can be further verified and supplemented, providing more comprehensive and accurate information for determining maintenance tasks and intervals.

[0055] By implementing step S1, it can be ensured that the impact of functional failure on aircraft safety is fully considered in the subsequent maintenance task analysis, providing a strong guarantee for the formulation of scientific and reasonable maintenance plans.

[0056] In step S2, it is necessary to consider not only whether the functional failure has a direct harmful effect on the operability of the aircraft, but also whether the functional failure has a direct harmful effect on the aircraft's mission execution.

[0057] Furthermore, direct adverse effects on aircraft operability. Failure of functions that may directly affect aircraft operability include, but are not limited to:

[0058] Degraded flight performance: such as reduced thrust, insufficient lift, and poor maneuverability, all of which may limit the aircraft's flight altitude, speed, or range.

[0059] Reduced fuel efficiency: Failure of certain functions may cause the engine or other systems to operate less efficiently, resulting in increased fuel consumption.

[0060] System stability issues: Functional failure may cause system instability, such as electrical system failure, hydraulic leakage, etc., which will affect the overall operational stability of the aircraft.

[0061] Direct adverse effects on the aircraft's ability to perform its mission. In addition to the effects on operability, special attention should be paid to how the failure affects the aircraft's ability to perform a specific mission, including but not limited to:

[0062] Mission completion efficiency: Functional failure may lead to extended mission execution time, such as detection equipment failure in search and rescue missions, loading and unloading system failure in cargo transportation missions, etc.

[0063] Mission execution effect: The failure of certain functions may directly affect the effectiveness of mission execution, such as the failure of reconnaissance equipment in a reconnaissance mission, the failure of the fire extinguishing system in a fire extinguishing mission, etc.

[0064] Mission safety: Functional failure may increase the safety risk during mission execution, such as navigation equipment failure at night or in severe weather conditions, emergency system failure in emergency situations, etc.

[0065] In this embodiment, the above step S2 specifically includes:

[0066] Clarify the type of mission, mission requirements and mission environment that the aircraft needs to perform, so as to more accurately assess the impact of functional failure on mission execution;

[0067] For each potential functional failure mode, analyze its specific impact on the aircraft's operability and mission performance, including the severity of the impact, probability of occurrence, and ease of detection;

[0068] Risk assessment tools are used to quantify the impact of functional failures and determine their specific risk level to aircraft operability and mission performance.

[0069] In this embodiment, step S3 includes:

[0070] Step S3-1, collecting maintenance task data, including data of planned maintenance tasks and unplanned maintenance tasks, and dividing the collected data into two groups according to complete data (M) and missing data (N);

[0071] Step S3-2, using a two-parameter Weibull distribution maximum likelihood estimation method to determine a shape parameter β and a scale parameter η of the two-parameter Weibull distribution;

[0072] Step S3-3, according to the upper limits of the failure rates defined for different failure types, combined with the obtained parameters of the two-parameter Weibull distribution, the optimal maintenance interval is obtained.

[0073] Further, in step S3-1, the collected data are divided into two groups according to complete data (M) and missing data (N).

[0074] Among them, planned maintenance tasks refer to maintenance tasks formulated according to the MSG-3 analysis logic; unplanned maintenance tasks refer to maintenance tasks of the same type of parts used with other models before the detailed design of the aircraft is completed; complete data refers to the operating time t from the first use or maintenance to (re) failure; missing data refers to the failure occurring before or after time t.

[0075] In the above step S3-2, the cumulative distribution function of the two-parameter Weibull distribution is expressed as the following formula:

[0076] .

[0078] In the above step S3-2, the probability density function of the two-parameter Weibull distribution is expressed as the following formula:

[0079]

[0080] Among them, the shape parameter β determines the shape of the cumulative distribution function, and the scale parameter η determines the degree of expansion and contraction of the cumulative distribution function in the horizontal direction.

[0081] In the above step S3-2, the two-parameter Weibull distribution maximum likelihood estimation function is expressed as the following formula:

[0082]

[0083] In step S3-2, using the maintenance task data collected in step S3-1, let Computes the shape parameter β and scale parameter η of the two-parameter Weibull distribution.

[0084] In step S3-3, the optimal maintenance interval is solved according to the failure rates of different failure types in combination with the obtained cumulative distribution function.

[0085] Specifically, after determining the parameters of the two-parameter Weibull distribution, it is necessary to solve the optimal maintenance interval according to different failure types of the equipment (each type may have a different upper limit of the failure rate), including the following steps:

[0086] Determine an upper limit on failure rate: Set an acceptable upper limit on failure rate for each failure type based on equipment reliability requirements or industry standards.

[0087] Using CDF to solve the maintenance interval: For a given upper limit R of the failure rate, we need to find the corresponding time T so that F(T) = R, that is, Solving this equation yields T, the optimal maintenance interval.

[0088] Of course, after obtaining the theoretically optimal maintenance interval, it is also necessary to consider factors such as the feasibility of actual operation and cost-effectiveness and make appropriate adjustments to the maintenance interval.

[0089] In summary, step S3 provides a scientific basis for equipment maintenance management by collecting maintenance task data, applying two-parameter Weibull distribution for parameter estimation, and solving the optimal maintenance interval in combination with the upper limit of the failure rate.

[0090] Furthermore, in step S4, it is determined that the maintenance task to be revised meets the requirements of safety, operability and economy at the same time.

[0091] In the above step S4, the specific maintenance task type and the corresponding maintenance interval are determined, including: identifying the different types of maintenance tasks that need to be performed, such as normal inspection, preventive replacement, troubleshooting, etc. Assign priority to each task based on the severity of the functional failure, the scope of impact, and the availability of maintenance resources. Determine the execution frequency of each maintenance task (i.e., maintenance interval) to ensure that potential problems can be discovered and repaired in a timely manner, while avoiding waste of resources caused by excessive maintenance. Develop a detailed maintenance plan and procedure, including maintenance steps, required tools, spare parts list, and personnel qualification requirements.

[0092] In summary, the present invention establishes a database and extracts relevant functional failure data. This method can use a large amount of actual data to support analysis, making the judgment more scientific and objective. The present invention uses a two-parameter Weibull distribution model to fit the fault data, which can more accurately describe the failure law of the equipment, thereby improving the reliability of the prediction results.

[0093] The present invention not only focuses on the impact of functional failure on aircraft safety, but also comprehensively considers the direct impact of functional failure on aircraft operability and mission execution capabilities, ensuring the comprehensiveness of the analysis. The present invention comprehensively evaluates the maintenance task type and maintenance interval from the perspective of the system / power unit as a whole, which helps to formulate a more reasonable maintenance plan. Based on the prediction results of the model, the present invention can dynamically adjust the maintenance interval obtained from the analysis to adapt to changes in the actual operating status of the equipment.

[0094] The present invention can effectively control maintenance costs and improve economic benefits while ensuring equipment safety through scientific and reasonable maintenance tasks and interval settings. The present invention can reduce unnecessary maintenance activities, improve equipment availability and operating efficiency, and provide strong support for airline operations. The present invention clarifies the standardized process from database establishment, data extraction, failure judgment, operating data analysis to maintenance tasks and interval evaluation, which helps to improve work efficiency and reduce human errors.

[0095] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0096] The above-mentioned embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and substitutions made by technicians in this field on the basis of the present invention shall fall within the scope of protection required by the present invention.

Claims

1. A method for determining maintenance tasks and intervals during aircraft system / power plant analysis, characterized in that: The method comprises the following steps: Step S1, establishing a database, extracting functional failure data related to the system / power unit to be analyzed from the database, and using the data to determine whether the aircraft functional failure affects the aircraft safety; Step S2, determining whether the aircraft function failure directly has a negative impact on the aircraft operability or the aircraft's mission execution; Step S3, collecting and analyzing the actual operation data of the aircraft, applying a two-parameter Weibull distribution model to fit the fault data, and adjusting the maintenance interval obtained by the analysis according to the model prediction results; Step S4, evaluating the system / power unit maintenance task type and maintenance interval.

2. The method according to claim 1, characterized in that: In step S1 , the database contains functional failure data that are analyzed to have an impact on aircraft safety during the aircraft design phase and functional failure data of historical aviation unsafe events.

3. The method according to claim 1, characterized in that: When determining whether an aircraft functional failure affects aircraft safety, the collected data is analyzed in detail to identify functional failure modes that have potential impacts on aircraft safety. Risk assessment tools are used to conduct quantitative assessments of the identified functional failures to determine their specific impact on aircraft safety.

4. The method according to claim 1, characterized in that: The step S2 specifically includes: Clarify the type of mission, mission requirements and mission environment that the aircraft needs to perform, so as to more accurately assess the impact of functional failure on mission execution; For each potential functional failure mode, analyze its specific impact on the aircraft's operability and mission performance, including the severity of the impact, probability of occurrence, and ease of detection; Risk assessment tools are used to quantify the impact of functional failures and determine their specific risk level to aircraft operability and mission performance.

5. The method according to claim 1, characterized in that Step S3 includes: Step S3-1, collecting maintenance task data, including data of planned maintenance tasks and unplanned maintenance tasks; Step S3-2, using a two-parameter Weibull distribution maximum likelihood estimation method to determine a shape parameter β and a scale parameter η of the two-parameter Weibull distribution; Step S3-3, according to the upper limits of the failure rates defined for different failure types, combined with the obtained parameters of the two-parameter Weibull distribution, the optimal maintenance interval is obtained.

6. The method according to claim 5, characterized in that: In step S3-2, the cumulative distribution function of the two-parameter Weibull distribution is expressed as the following formula:

7. The method according to claim 5, characterized in that: In step S3-2, the probability density function of the two-parameter Weibull distribution is expressed as the following formula: Among them, the shape parameter β determines the shape of the cumulative distribution function, and the scale parameter η determines the degree of expansion and contraction of the cumulative distribution function in the horizontal direction.

8. The method according to claim 5, characterized in that: In step S3-2, the two-parameter Weibull distribution maximum likelihood estimation function is expressed as the following formula:

9. The method according to claim 5, characterized in that: In step S3-2, using the maintenance task data collected in step S3-1, let Computes the shape parameter β and scale parameter η of the two-parameter Weibull distribution.

10. The method according to claim 5, characterized in that: In step S3-3, the optimal maintenance interval is solved according to the failure rates of different failure types in combination with the obtained cumulative distribution function.

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