Cost-oriented civil aircraft fleet planned maintenance scheme optimization method

Abstract

The invention provides a cost-oriented civil aircraft fleet planned maintenance scheme optimization method, relates to the field of regular maintenance plan and cost optimization of an aircraft fleet, and aims to improve the maintenance efficiency of the aircraft fleet and reduce resource waste in task intervals. According to the method, the optimal maintenance frequency and interval are realized by integrating the regular inspection plans and combining the balanced maintenance strategy. According to the method, a discrete event simulation model is adopted, a fleet maintenance plan is subjected to multi-dimensional simulation and optimization, and an efficient maintenance task allocation scheme is formulated according to constraint conditions such as fleet scale, flight hours, task types and hangar resources. Through optimization of a maintenance task distribution mode and fine adjustment of task intervals, the maintenance cost of a fleet can be effectively reduced, and the airworthiness and the utilization rate of aircrafts are improved. The method provides a scientific basis for an airline company to make a maintenance decision, and has an important application value for optimizing the operation and maintenance cost of an aviation fleet.

Description

Technical Field

[0001] The present invention relates to the field of optimizing the regular maintenance costs of an airline fleet, and particularly to a civil aviation fleet scheduled maintenance decision-making mechanism and cost optimization method combining discrete event simulation and A-check interval optimization. Background Art

[0002] With the development of modern civil aviation technology, the management requirements for civil aviation aircraft maintenance have been continuously increasing. Currently, the aircraft maintenance mode still mainly relies on planned maintenance based on time and flight cycles. This mode usually includes tasks such as regular inspections, line checks, component maintenance, seasonal maintenance, etc., to ensure that the aircraft meets the continuous airworthiness standards. The Maintenance Planning Document (MPD) and industry standards provide guidance for planned maintenance tasks, forming a relatively systematic regular inspection arrangement, such as A-checks, C-checks, etc.

[0003] Regular inspections (such as A-checks and C-checks) are the core components of planned maintenance. The maintenance tasks are arranged strictly according to the specified intervals to prevent potential failures from affecting flight safety. However, an important challenge in the current maintenance mode is how to reasonably set and optimize the maintenance intervals to minimize the aircraft ground time and resource waste. In the traditional mode, overly frequent inspections will increase the operating costs, while too long intervals may lead to insufficient maintenance of key systems, affecting the reliability and airworthiness of the aircraft. Therefore, reasonably optimizing the maintenance intervals and task allocation is of great significance for improving the operating efficiency of airlines and reducing maintenance costs.

[0004] Existing research shows that through the reasonable allocation of maintenance tasks and dynamic adjustment of intervals, the utilization efficiency of maintenance resources can be further improved on the premise of ensuring safety. However, how to reasonably divide maintenance tasks into various inspection cycles through a systematic analysis and decision-making mechanism while ensuring the optimal allocation of resources remains a problem that needs to be studied. Based on this, a new maintenance plan decision-making method based on discrete event simulation models and cost optimization is proposed, which can effectively reduce the waste of maintenance resources, improve the operating efficiency of the fleet, and provide scientific support for airlines in formulating maintenance plans. Summary of the Invention

[0005] Objective of the Invention: The present invention aims to solve the problems of unreasonable arrangement of regular maintenance tasks and insufficient optimization of maintenance costs in the prior art, and provides a method for optimizing the planned maintenance scheme of a civil aircraft fleet oriented to cost. This method establishes a discrete event simulation model to optimize the task allocation and interval setting of A-checks, so as to comprehensively analyze and balance maintenance costs, downtime, and resource utilization efficiency. Through this method, airlines can effectively reduce the overall maintenance cost and optimize the allocation of maintenance resources on the premise of ensuring the continuous airworthiness and operation efficiency of the aircraft, providing a scientific decision-making basis for the regular maintenance of the fleet.

[0006] The method of the present invention includes the following steps:

[0007] Step 1: Determine the operation parameters of the fleet according to historical operation information;

[0008] Step 2: Based on the operation parameters of the fleet, adopt an equilibrium maintenance strategy to establish a discrete event simulation model, simulate the maintenance execution situation of the fleet in each time period, and generate the A-check time plan and C-check time plan under the traditional interval;

[0009] Step 3: Use the sequence of aircraft waiting for inspection output by the simulation model, and calculate the execution date of the scheduled inspection task according to the scheduled inspection task interval information and the average daily utilization rate information of the fleet;

[0010] Step 4: According to the principle of first come first served, divide the maintenance tasks into the corresponding A-check or C-check to generate the scheduled inspection work execution plan;

[0011] Step 5: Calculate the ground stop cost, total man-hour cost of A-check and C-check, waste cost, and post-flight man-hour cost of the scheduled inspection work execution plan;

[0012] Step 6: Set different A-check intervals, and repeat Steps 3 to 6 for different A-check intervals;

[0013] Step 7: Compare the scheduled inspection work task execution plans of the fleet generated by the discrete event simulation model under the traditional interval and different A-check intervals to achieve the maximum benefit of the overall maintenance decision-making framework.

[0014] In Step 1, the relevant operation parameters of the fleet include fleet information, scheduled inspection task attributes, and constraint information;

[0015] The fleet information includes fleet size, utilization rate, and initial state;

[0016] The scheduled inspection task attributes include task interval and task type;

[0017] The constraint information includes A-check interval, C-check interval, and the number of hangars.

[0018] In Step 2, the balanced maintenance strategy means: the maintenance plan formulated by dividing the maintenance tasks into small work packages can be completed not only during the regular inspection period, but also during the overnight period after the aircraft's flight. The basis for task division includes task nature, task interval, and task complexity. For example:

[0019] The lubrication inspection task can be separately divided into an after-flight work package and completed during the aircraft's overnight parking time;

[0020] The consumable replacement and structure inspection tasks are divided into scheduled inspection work packages and executed during an A-check or C-check;

[0021] The engine performance inspection task can be refined into multi-stage tasks and flexibly completed in combination with the after-flight and scheduled inspection arrangements.

[0022] In Step 2, the discrete event simulation model includes an initialization module, an outbound module, a waiting inspection module, an inbound module, and a time update module;

[0023] The initialization module is used to initialize the information format required for the simulation;

[0024] The outbound module is used to update the available A-check and C-check hangar quantities and the aircraft's own status attributes according to the initial aircraft status information, and provide updated information for the waiting inspection module;

[0025] The waiting inspection module updates the waiting inspection aircraft sequence based on the different states of different aircraft in the fleet and different inspection interval requirements;

[0026] The inbound module updates the available maintenance resources and the waiting inspection aircraft sequence based on the outbound module and the waiting inspection module;

[0027] The time update module records the states of each aircraft in the fleet and controls the advancement of the simulation process.

[0028] Step 3 includes:

[0029] Step 3-1, output the waiting inspection aircraft sequence through the simulation model. The waiting inspection aircraft sequence refers to a list composed of aircraft that have reached the scheduled inspection task interval condition but have not yet completed the maintenance assignment according to the aircraft's operating status (such as flight hours, flight cycles, or calendar time) and scheduled inspection task attributes (such as task interval);

[0030] Step 3-2, calculate the scheduled inspection task interval: the scheduled inspection task deadline is determined by the minimum value among the flight hours (FH), flight cycles (FC), and calendar time (DAY) specified in the scheduled inspection task attributes;

[0031] Step 3-3: Combine the sequence of aircraft to be inspected in the simulation model with the information on the average daily utilization rate of the fleet, and dynamically update the priority of task allocation to avoid waste of time intervals caused by resource waste or task conflicts.

[0032] In Step 4, the principle of first come first served means that the inspection task intervals are specified in flight hours (FH), flight cycles (FC), calendar time (DAY), and combinations of flight hours, flight cycles, and calendar time; the deadline of the task is determined by the task interval, and the task must be executed before the task deadline; in the case of a combined time interval, the deadline of the task is determined by the earliest arriving time interval; the utilization rate is used to dynamically evaluate the speed at which the aircraft reaches the task interval, and in combination with the task interval and the utilization rate, the earliest deadline of the task is predicted.

[0033] For example: The interval for a certain maintenance task is 500 FH or 90 DAY. The utilization rate of aircraft A is 8 FH / day, and the utilization rate of aircraft B is 4 FH / day.

[0034] For aircraft A: The deadline for the 500 FH task is 500 / 8 = 62.5 days, which is earlier than 90 days. Therefore, the task deadline is determined based on FH.

[0035] For aircraft B: The deadline for the 500 FH task is 500 / 4 = 125 days, which is later than 90 days. Therefore, the task deadline is determined based on DAY.

[0036] In Step 4, each scheduled inspection task belongs to a certain type of scheduled inspection, and the task can be executed in a higher-level scheduled inspection than the scheduled inspection type. That is, when the scheduled inspection task belongs to an A-check task, the task can be assigned to be executed in an A-check or a C-check; when the scheduled inspection task belongs to a C-check task, the task can only be assigned to be executed in a C-check.

[0037] In Step 5, define the evaluation indicators for the scheduled inspection plan, which are used to analyze the maintenance plan output by the discrete event simulation model. The evaluation indicators for the scheduled inspection plan include: ground stop cost, total man-hour cost of A-checks and C-checks, waste (escalation) cost, and post-flight man-hour cost.

[0038] According to the scheduled inspection time plan, count the number of days of ground stop caused by insufficient hangar space and the number of days when the aircraft cannot execute flights due to scheduled inspections, and then multiply by the ground stop rate to obtain the ground stop cost of the fleet, the ground stop cost C AOG The calculation formula is:

[0039] C AOG =(DAYS AOG_A +DAYS AOG_C )*r AOG

[0040] Where DAYSAOG_A Indicates the number of days of aircraft grounding caused by A-check, DAYS AOG_C Indicates the number of days of aircraft grounding caused by C-check, r AOG Indicates the grounding rate;

[0041] According to the maintenance work execution plan, count the maintenance tasks of A / C-check and the man-hours required. Since the labor rates for A-check and C-check are the same, multiply them by the man-hour rate to calculate the total man-hour cost C of A-check and C-check AC_MH , the total man-hour cost C of A-check and C-check AC_MH The calculation formula is:

[0042] C AC_MH =(MH A +MH C )*r MH

[0043] Where MH A Indicates the man-hours of A-check, MH C Indicates the man-hours of C-check, r MH Indicates the man-hour rate;

[0044] First, define the wasted man-hours. When assigning the scheduled check tasks, it is rare that the interval between scheduled check tasks exactly matches the scheduled check interval. More often, when the scheduled check time arrives, the interval between scheduled check tasks has not been reached yet. If this scheduled check task is assigned to the next scheduled check opportunity, it will exceed this task interval. Therefore, it is necessary to execute this scheduled check task in advance. Assume that it needs to be executed t e in advance, and the interval of the scheduled check task itself is t, and the man-hours required to execute the scheduled check task is MH. Then the wasted man-hours MH e Are defined by the following formula:

[0045] The wasted cost C e The calculation formula is:

[0046]

[0047] C e =MH e *r MH

[0048] Where MH indicates the man-hours required to execute the task, t e Indicates the time in advance of the scheduled check task, t indicates the interval of the scheduled check task itself, MH e Indicates the wasted man-hours;

[0049] Some tasks with an interval less than the A-check interval will be arranged to be executed after flight. The after-flight man-hour cost C LINE_MH The calculation formula is:

[0050] C LINE_MH =MHLINE *r MH

[0051] Among them, MH LINE represents the man-hours after flight.

[0052] In step 7, in the discrete event simulation model, the A-check interval is input as a parameter, and two or more candidate values (such as 600 FH, 700 FH, 800 FH, etc.) are set. The simulation model dynamically generates a maintenance plan for each interval according to the input A-check interval, and compares the total execution times, average execution times, average execution intervals, average man-hours, average wasted man-hours, and grounding rates of the scheduled maintenance tasks at different A-check intervals;

[0053] The present invention also provides a storage medium storing a computer program or instruction, which, when the computer program or instruction is run, implements the method described above.

[0054] The beneficial effects of the present invention are as follows: It provides a cost-oriented method for optimizing the regular maintenance of a civil aircraft fleet. By optimizing the A-check task interval and allocation, the overall maintenance cost of the fleet is significantly reduced. The present invention utilizes a discrete event simulation model to evaluate the downtime, man-hour cost, and resource waste under different maintenance plans, and optimizes the allocation and execution of maintenance tasks from the perspective of cost. By reasonably adjusting the maintenance interval, the efficient utilization of maintenance resources is achieved, unnecessary downtime and task redundancy are reduced, and scientific maintenance decision support is provided for airlines while ensuring the continuous airworthiness and efficient operation of aircraft. Description of the Drawings

[0055] The following further specifically describes the present invention in conjunction with the drawings and specific embodiments, and the above-mentioned advantages of the present invention and / or other aspects will become clearer.

[0056] Figure 1 is the flowchart of the present invention.

[0057] Figure 2 is the discrete event simulation model of the scheduled maintenance plan in the embodiment of the present invention.

[0058] Figure 3 is the schematic diagram of the fleet scheduled maintenance plan arrangement in the embodiment of the present invention.

[0059] Figure 4a is the distribution of man-hours of the fleet scheduled maintenance tasks (A-check man-hours) in the embodiment of the present invention.

[0060] Figure 4b is the distribution of man-hours of the fleet scheduled maintenance tasks (C-check man-hours) in the embodiment of the present invention.

[0061] Figure 5This is the trend of the total operating cost of the fleet in the embodiments of the present invention.

[0062] Figure 6a This is the statistics of the ground time cost of the fleet in the embodiments of the present invention.

[0063] Figure 6b This is the statistics of the total man-hour cost of AC checks for the fleet in the embodiments of the present invention.

[0064] Figure 6c This is the statistics of the waste cost of the fleet in the embodiments of the present invention.

[0065] Figure 6d This is the statistics of the man-hour cost after flight for the fleet in the embodiments of the present invention. Detailed implementation manners

[0066] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below in conjunction with the specific implementation manners.

[0067] The embodiments of the present invention provide a method for optimizing the planned maintenance plan of a civil aircraft fleet oriented to cost. The flowchart is as Figure 1 shown and includes:

[0068] Step 1: Determine the relevant operating parameters of the fleet, including:

[0069] (1) Fleet information: fleet size, utilization rate, initial state

[0070] (2) Attributes of scheduled maintenance tasks: task interval, task type

[0071] (3) Constraint information: A and C check intervals, number of hangars

[0072] Specific model information comes from the actual fleet operation data of an airline in 2020. See Table 1 below for details.

[0073] Table 1

[0074]

[0075] Step 2: Based on the operating parameters of the fleet, adopt an equilibrium maintenance strategy to establish a discrete event simulation model, as Figure 2 shown, simulate the maintenance execution situation of the fleet in each time period, generate the A-check time plan and C-check time plan under the traditional interval; adopt the equilibrium maintenance strategy, combine the scheduled maintenance task interval (based on flight hours, flight cycles and calendar time), determine the deadline of the maintenance task, and arrange the maintenance tasks according to the principle of "first come, first served". According to the intervals of A and C checks, aircraft utilization rate and task interval, optimize the allocation of maintenance tasks, reasonably allocate each task to the scheduled maintenance, and minimize the waste of task interval time to the greatest extent, so as to formulate the final scheduled maintenance plan, asFigure 3 As shown. The input of the discrete event simulation model in Step 2 is shown in Table 2 below.

[0076] Table 2

[0077]

[0078] (1) Initialization module: Input the information required for simulation, load each module and start the simulation process.

[0079] (2) Outbound module: Judge whether the aircraft maintenance work is completed, the expired aircraft leaves the warehouse, and update the hangar quantity and aircraft status.

[0080] (3) Inspection waiting module: According to the aircraft status and inspection interval, list the expired aircraft in the inspection waiting aircraft sequence and update its status.

[0081] (4) Inbound module: When the hangar is available, arrange the inspection waiting aircraft to enter the warehouse for maintenance according to the first-come-first-served rule, and update the aircraft attributes and hangar status.

[0082] (5) Time update module: Update the service life of the in-wing aircraft and the inspection time of the aircraft under inspection, and increase the simulation cycle by one day.

[0083] It should be noted that according to the model inputs of Step 1 and Step 2, in order to ensure the rationality of the simulation, the following constraints need to be considered in the model:

[0084] (1) Maintenance interval constraint: For aircraft in normal flight state, the interval time between each A and C inspections is not greater than the specified execution cycle time (whichever comes first).

[0085] (2) Hangar quantity constraint: The number of aircraft undergoing A and C inspections simultaneously cannot exceed the existing number of A and C inspection hangars

[0086] (3) Maintenance task type constraint: Each scheduled inspection task belongs to a certain scheduled inspection type, and this task can be executed in a scheduled inspection higher than the scheduled inspection type. When the scheduled inspection task belongs to an A inspection task, this task can be assigned to either an A inspection or a C inspection for execution; when the scheduled inspection task belongs to a C inspection task, this task can only be assigned to a C inspection for execution;

[0087] Step 3: Calculate the scheduled inspection work task dates based on the scheduled inspection task interval information and the fleet average daily utilization rate information;

[0088] Step 4: Divide the maintenance tasks into the corresponding A inspections or C inspections according to the principle of whichever comes first, and generate a scheduled inspection work execution plan;

[0089] Step 5: Based on the maintenance plan output by the discrete event simulation model and combined with the interval settings of the scheduled inspections, analyze the defined evaluation indicators for the scheduled inspection plan (including downtime cost, man-hour cost, post-flight man-hour cost, and waste cost) to determine the optimization objectives for the periodic maintenance.

[0090] Statistically analyze the maintenance man-hours for each scheduled inspection (as shown in Figure 4a , Figure 4b ). For the A-check man-hours of the fleet within the 4-year planning period, they are mainly concentrated within 100 man-hours, while the C-check man-hours are distributed within 3,800 - 4,300 man-hours. Table 3 shows the execution times and man-hour situations of the A-check and C-check. Among them, the average man-hour of the A-check is 54.73, the wasted man-hour is 34.84, and the waste ratio is as high as 63.66%. In contrast, the average man-hour of the C-check is 4,041.01, and the waste ratio is only 20.21%. This indicates that the interval setting of the A-check may be unreasonable, and its impact on the operating cost will be discussed in detail in the next section.

[0091] Table 3

[0092]

[0093] Step 6: Set different A-check intervals and repeat Steps 3, 4, 5, and 6 for different A-check intervals.

[0094] In this embodiment, the A-check interval is optimized to reduce the operating cost. Since most aircraft perform the A-check according to the calendar time, the calendar interval of the A-check is optimized. The A-check interval is gradually increased from 60 days in 5-day steps to 300 days, and the operating cost is statistically analyzed. The results are as shown in Figure 5 . The optimal interval is 500 FH and 165 DAY, and the lowest operating cost is $26.934 million, which is about 9.5% lower than the $29.7594 million before optimization (Table 4). The execution times of the A-check are reduced from 279 times to 145 times, the average man-hour for each execution is 97.20, and the waste man-hour ratio is reduced from 63.66% to 37.84%.

[0095] Table 4

[0096]

[0097] Step 7: As the A-check interval increases, the operating cost shows a trend of first decreasing and then increasing (as shown in Figure 6a , Figure 6b , Figure 6c , Figure 6dAs shown, it can be seen that as the random A-check interval increases, the number of shutdowns will inevitably decrease, so the shutdown cost gradually decreases. When the A-check interval approaches the maintenance interval of the task itself, the waste cost of the task will inevitably decrease, the number of task executions will also decrease, and the A / C-check man-hour cost will also decrease. On the contrary, it will lead to an increase in cost. Therefore, the relationship between the A / C-check man-hour cost and the waste cost and the A-check interval is difficult to determine, showing a fluctuating change pattern. Of course, as the interval increases, more maintenance tasks will be carried out after flight. The advantage of carrying out tasks after flight is that the waste cost will decrease. So generally, the waste cost decreases as the A-check interval increases. However, the man-hour cost after flight will increase, ultimately leading to an increase in the total operating cost.

[0098] In specific implementation, the present application provides a computer storage medium and a corresponding data processing unit. Among them, the computer storage medium can store a computer program, and when the computer program is executed by the data processing unit, it can run the inventive content of the cost-oriented civil aircraft fleet planned maintenance scheme optimization method provided by the present invention and some or all of the steps in each embodiment. The storage medium can be a magnetic disk, an optical disk, a read-only memory (ROM), or a random access memory (RAM), etc.

[0099] The present invention provides a cost-oriented civil aircraft fleet planned maintenance scheme optimization method. There are many methods and ways to specifically implement this technical solution. The above is only the preferred implementation manner of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention. Each component not clearly defined in this embodiment can be implemented by existing technologies.

Claims

1. A cost-oriented optimization method for the planned maintenance scheme of a civil aircraft fleet, characterized in that Including the following steps: Step 1: Determine the operation parameters of the fleet according to the historical operation information; Step 2: Based on the operation parameters of the fleet, adopt an equilibrium maintenance strategy, establish a discrete event simulation model, simulate the maintenance execution of the fleet in each time period, and generate the A-check time plan and C-check time plan under the traditional interval; Step 3: Using the queuing aircraft sequence output by the simulation model, calculate the execution date of the scheduled maintenance task according to the scheduled maintenance task interval information and the average daily utilization rate information of the fleet; Step 4: According to the principle of first come first served, divide the maintenance tasks into the corresponding A-check or C-check to generate the execution plan of the scheduled maintenance work; Step 5: Calculate the ground stop cost, total man-hour cost of A-check and C-check, waste cost, and post-flight man-hour cost of the execution plan of the scheduled maintenance work; Step 6: Set different A-check intervals, and repeat steps 3 to 6 for different A-check intervals; Step 7: Compare the execution plans of the scheduled maintenance work tasks of the fleet generated by the discrete event simulation model under the traditional interval and different A-check intervals to achieve the maximum benefit of the overall maintenance decision-making framework.

2. The method according to claim 1, wherein In step 1, the relevant operation parameters of the fleet include fleet information, scheduled maintenance task attributes, and constraint information; The fleet information includes fleet size, utilization rate, and initial state; The scheduled maintenance task attributes include task interval and task type; The constraint information includes A-check interval, C-check interval, and the number of hangars; 3. The method according to claim 2, wherein In step 2, the equilibrium maintenance strategy refers to: a maintenance plan formulated by dividing the maintenance tasks into small work packages; 4. The method according to claim 3, wherein In step 2, the discrete event simulation model includes an initialization module, a departure module, a queuing module, an arrival module, and a time update module; The initialization module is used to initialize the information format required for the simulation; The departure module is used to update the available A-check and C-check hangar quantities and the aircraft's own state attributes according to the initial state information of the aircraft, and provide updated information for the queuing module; The queuing module updates the queuing aircraft sequence based on the different states of different aircraft in the fleet and different inspection interval requirements; The arrival module updates the available maintenance resources and the queuing aircraft sequence based on the departure module and the queuing module; The time update module records the states of each aircraft in the fleet and controls the advancement of the simulation process; 5. The method according to claim 4, wherein Step 3 includes: Step 3-1: Output the queuing aircraft sequence through the simulation model. The queuing aircraft sequence refers to a list composed of aircraft that have reached the scheduled maintenance task interval condition but have not completed the maintenance allocation according to the operation state and scheduled maintenance task attributes of the aircraft; Step 3-2: Calculate the scheduled maintenance task interval: The scheduled maintenance task deadline is determined by the minimum value of the flight hours, flight cycles, and calendar time specified in the scheduled maintenance task attributes; Step 3-3: Combine the queuing aircraft sequence of the simulation model with the average daily utilization rate information of the fleet to dynamically update the priority of task allocation.

6. The method according to claim 5, wherein In step 4, the principle of first come first served means that the specified inspection task intervals are specified in terms of flight hours, flight cycles, calendar time, and combinations of flight hours, flight cycles, and calendar time; the deadline for a task is determined by the task interval, and the task must be executed before the task deadline; in the case of a combined time interval, the deadline for the task is determined by the earliest arriving time interval; the utilization rate is used to dynamically evaluate the speed at which the aircraft reaches the task interval, and by combining the task interval and the utilization rate, the earliest deadline for the task is predicted.

7. The method according to claim 6, characterized in that, In step 4, each scheduled inspection task corresponds to a type of scheduled inspection. When the scheduled inspection task belongs to an A-check task, the task can be assigned to be executed in either an A-check or a C-check; when the scheduled inspection task belongs to a C-check task, the task can only be assigned to be executed in a C-check.

8. The method according to claim 7, wherein In step 5, evaluation indicators for the scheduled inspection plan are defined, which are used to analyze the maintenance plan output by the discrete event simulation model. The evaluation indicators for the scheduled inspection plan include: ground stop cost, total man-hour cost of A-checks and C-checks, waste cost, and post-flight man-hour cost. Parking cost C AOG The calculation formula is as follows: C AOG = (DAYS AOG_A + DAYS AOG_C ) * r AOG Among them, DAYS AOG_A represents the number of days of ground stop caused by A-check, DAYS AOG_C represents the number of days of ground stop caused by C-check, r AOG represents the ground stop rate; Total man-hour cost C for A and C inspections AC_MH The calculation formula is as follows: C AC_MH = (MH A + MH C ) * r MH Among them, MH A represents the working hours during A-check, MH C represents the working hours during C-check, r MH represents the labor-hour rate; Waste cost C e The calculation formula is as follows: C e = MH e * r MH Among them, MH represents the man-hours required to perform the task, t e represents the time ahead of the scheduled inspection task, t represents the interval of the scheduled inspection task itself, MH e represents the wasted man-hours; Post-flight man-hour cost C LINE_MH The calculation formula is as follows: C LINE_MH = MH LINE * r MH Among them, MH LINE represents the man-hours after flight.

9. The method according to claim 8, wherein In step 7, in the discrete event simulation model, the A-check interval is input as a parameter and two or more candidate values are set. The simulation model dynamically generates a maintenance plan for each interval based on the input A-check interval, and compares the total number of executions, average number of executions, average execution interval, average man-hours, average waste man-hours, and ground stop rate of the scheduled inspection tasks for different A-check intervals.

10. A storage medium, characterized in that, A computer program or instructions are stored, and when the computer program or instructions are run, the method according to any one of claims 1 to 9 is implemented.

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