Aircraft airbag deicing system safety evaluation and improvement method

Abstract

The invention belongs to the technical field of aircraft airbag deicing system design, and particularly relates to an aircraft airbag deicing system safety assessment and improvement method, which comprises the following steps: step 1, carrying out functional danger analysis on the failure state of an airbag deicing system, and determining a hazard level; 2, emergency operation is formulated according to the failure state of the air bag deicing system of the middle hazard level; 3, analyzing the damage degree of the failure state of the airbag deicing system for relieving the middle damage level according to the formulated emergency operation, and re-determining the damage level of the failure state of the airbag deicing system; and 4, performing safety assessment on the airbag deicing system, and improving the airbag deicing system according to an assessment result.

Description

Technical Field

[0001] The present application belongs to the technical field of aircraft airbag deicing system design, and specifically relates to a safety assessment of an aircraft airbag deicing system and an improvement method thereof. Background Art

[0002] When an aircraft flies in clouds containing supercooled water droplets, many parts will freeze, which will deteriorate the aircraft's lift-drag characteristics and reduce the aircraft's flight safety. For this purpose, an airbag de-icing system is designed.

[0003] The aircraft airbag de-icing system is a mechanical de-icing system. Inflatable airbags are arranged in the anti-icing area of ​​the aircraft. When ice forms, the airbags are periodically inflated to break the ice layer, and the airflow is used to blow away the broken ice, thereby achieving de-icing of the anti-icing area.

[0004] Aircraft airbag de-icing systems need to consider various unsafe factors at the early stage of design, conduct safety assessments, improve the design of the airbag de-icing system, and ensure the flight safety of the aircraft. However, at present, when conducting safety assessments on airbag de-icing systems, only the impact of the failure of the airbag de-icing system itself is considered, and there is a lack of consideration of the operation when the airbag de-icing system fails. The results of the safety assessment are quite different from the actual degree of hazard, and cannot effectively guide the improvement of the airbag de-icing system and obtain a reasonable and appropriate airbag de-icing system design plan.

[0005] This application is proposed in view of the above-mentioned technical defects. Summary of the invention

[0006] The purpose of this application is to provide a safety assessment method for an aircraft airbag de-icing system and an improvement method thereof, so as to overcome or alleviate at least one of the known technical defects.

[0007] The technical solution of this application is:

[0008] A safety assessment and improvement method for an aircraft airbag deicing system, comprising:

[0009] Step 1: Conduct functional hazard analysis on the failure state of the airbag de-icing system to determine the hazard level;

[0010] Step 2: Develop emergency operations for air bag de-icing system failure conditions of intermediate hazard levels;

[0011] Step 3: Analyze the degree of harm caused by the failure state of the airbag de-icing system with an intermediate harm level according to the emergency operation, and redetermine the harm level of the failure state of the airbag de-icing system;

[0012] Step 4: Conduct a safety assessment on the airbag de-icing system and improve the airbag de-icing system based on the assessment results.

[0013] According to at least one embodiment of the present application, in the above-mentioned aircraft airbag de-icing system safety assessment and improvement method, in step four, if the hazard level of the airbag de-icing system failure state does not reach the intermediate or higher hazard level, there is no need to improve the airbag de-icing system.

[0014] According to at least one embodiment of the present application, in the above-mentioned aircraft airbag de-icing system safety assessment and improvement method, in step four, if the hazard level of the airbag de-icing system failure state exists at an intermediate or higher hazard level, a Markov model is constructed to calculate the probability of occurrence of an airbag de-icing system failure state of an intermediate or higher hazard level. If the probability is less than the safety-allowed probability, there is no need to improve the airbag de-icing system. If the probability is greater than the safety-allowed probability, it is necessary to improve the airbag de-icing system, and repeat steps one to four.

[0015] According to at least one embodiment of the present application, in the above-mentioned aircraft airbag deicing system safety assessment and improvement method, in step 4, if the hazard level of the airbag deicing system failure state has an intermediate or higher hazard level, a Markov model is constructed to calculate the probability of occurrence of an airbag deicing system failure state of an intermediate or higher hazard level, specifically:

[0016] Define the state before the failure state of the air bag de-icing system with intermediate and higher hazard levels occurs;

[0017] Determine the state before the failure state of the airbag deicing system with intermediate or higher hazard levels occurs, and the transition relationship between the failure state of the airbag deicing system with intermediate or higher hazard levels, and draw a state transition diagram;

[0018] Assign the state of the airbag de-icing system before the failure state of the intermediate and above hazard level occurs, the probability of transition to the failure state of the airbag de-icing system of the intermediate and above hazard level, list the relevant differential equations, and calculate the probability of the failure state of the airbag de-icing system of the intermediate and above hazard level.

[0019] According to at least one embodiment of the present application, in the above-mentioned aircraft airbag de-icing system safety assessment and improvement method thereof, improving the airbag de-icing system specifically includes improving the logical architecture of the airbag de-icing system or adding a protective design.

[0020] According to at least one embodiment of the present application, in the above-mentioned aircraft airbag de-icing system safety assessment and improvement method thereof, the hazard level of the airbag de-icing system failure state is divided with reference to SAE 4761, and is divided into I, II, III, IV, and V from high to low.

[0021] This application has at least the following beneficial technical effects:

[0022] A safety assessment and improvement method for an aircraft airbag de-icing system is provided. When conducting a safety assessment on an aircraft airbag de-icing system, the hazard level of a failure state of an airbag de-icing system of an intermediate hazard level is mitigated according to the established emergency operations, and the hazard level of the failure state of the airbag de-icing system is re-determined. The result of the safety assessment is quite different from the actual hazard level, which can effectively guide the improvement of the airbag de-icing system and obtain a reasonable and appropriate airbag de-icing system design scheme. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the safety assessment and improvement method of the aircraft airbag de-icing system provided in the embodiment of the present application. DETAILED DESCRIPTION

[0024] In order to make the technical solution and advantages of the present application clearer, the technical solution of the present application will be described in further detail in detail and in detail with reference to the accompanying drawings. It can be understood that the specific embodiments described here are only partial embodiments of the present application, which are only used to explain the present application, not to limit the present application. It should be noted that, for the convenience of description, only the parts related to the present application are shown in the accompanying drawings, and other related parts can refer to the general design.

[0025] In addition, unless otherwise defined, the technical terms or scientific terms used in the description of this application should have the common meanings understood by ordinary technicians in the field to which this application belongs.

[0026] A safety assessment and improvement method for aircraft airbag deicing system, such as Figure 1 As shown, the following steps are included.

[0027] Step 1: Conduct a functional hazard analysis on the failure state of the airbag de-icing system to determine the hazard level.

[0028] Through the analysis of mission scenarios, the impact of the failure state of the airbag de-icing system on the crew, personnel and mission is analyzed, and the hazard level of the failure state of the airbag de-icing system is determined.

[0029] The hazard level of the failure state of the airbag de-icing system can be divided with reference to SAE 4761, and can be divided into I, II, III, IV, and V from high to low. Among them, hazard level I is that the aircraft is seriously damaged, the aircraft is destroyed, and it cannot continue to perform the mission, and the safety of the crew and personnel is seriously threatened; hazard level II is that the aircraft is seriously damaged, greatly reducing the function and safety margin of the aircraft, but can continue to perform the mission, and the safety of the crew and personnel is threatened to a large extent; hazard level III is that the aircraft is damaged, the function and safety margin of the aircraft are significantly reduced, but the mission can be continued, and the safety of the crew and personnel is threatened to a certain extent; hazard level IV is that the aircraft is damaged, the function and safety margin of the aircraft are slightly reduced, the mission can be continued, and the crew and personnel are slightly threatened; hazard level V is that the aircraft malfunctions, with almost no impact on the operation and safety of the aircraft, the mission can be continued, and the safety of the crew and personnel is not threatened.

[0030] In the case of hazard level I, the airbag de-icing system failure state will cause serious damage to the aircraft and there is no possibility of operational mitigation. In the case of hazard level II, III, and IV, the degree of hazard can be mitigated or even eliminated through operation. In the case of hazard level V, the airbag de-icing system failure state has almost no impact on the operation and safety of the aircraft, and the mission can be continued. The safety of the crew and personnel is not threatened, and no operation is required to mitigate the situation.

[0031] Step 2: Develop emergency operations for air bag de-icing system failure conditions of intermediate hazard levels.

[0032] Emergency operations can be formulated for air bag de-icing system failure states with hazard levels II, III, and IV, that is, air bag de-icing system failure states with intermediate hazard levels. When the air bag de-icing system fails with hazard levels II, III, and IV, the formulated emergency operations shall be followed to mitigate the degree of hazard, reduce the hazard level, or eliminate the hazard.

[0033] Step 3: Analyze the emergency operations to mitigate the hazard level of the airbag de-icing system failure state at the intermediate hazard level, and redetermine the hazard level of the airbag de-icing system failure state.

[0034] When an airbag de-icing system failure state with an intermediate hazard level occurs, operations shall be performed in accordance with the established emergency operations. In the mission scenario, operational errors such as insufficient operational level, operational errors, incorrect operations and omissions may occur. When analyzing the degree of hazard, it is necessary to consider the impact of operational errors on the crew, personnel and mission, and redetermine the hazard level of this type of airbag de-icing system failure state.

[0035] Step 4: Conduct a safety assessment on the airbag de-icing system and improve the airbag de-icing system based on the assessment results.

[0036] If the hazard level of the airbag de-icing system failure state does not reach the intermediate or higher hazard levels (I, II, III, IV), there is no need to improve the airbag de-icing system.

[0037] If the hazard level of the airbag de-icing system failure state is intermediate or above, a Markov model is constructed to calculate the probability of the airbag de-icing system failure state of intermediate or above hazard levels. If it is less than the safety-allowed probability, there is no need to improve the airbag de-icing system. If it is greater than the safety-allowed probability, the airbag de-icing system needs to be improved, and steps 1 to 4 are repeated.

[0038] A Markov model is constructed to calculate the probability of failure of the airbag deicing system at intermediate and higher hazard levels, specifically:

[0039] Define the state before the failure state of the air bag de-icing system with intermediate and higher hazard levels occurs;

[0040] Determine the state before the failure state of the airbag deicing system with intermediate or higher hazard levels occurs, and the transition relationship between the failure state of the airbag deicing system with intermediate or higher hazard levels, and draw a state transition diagram;

[0041] Assign the state of the airbag de-icing system before the failure state of the intermediate and above hazard level occurs, the probability of transition to the failure state of the airbag de-icing system of the intermediate and above hazard level, list the relevant differential equations, and calculate the probability of the failure state of the airbag de-icing system of the intermediate and above hazard level.

[0042] Improvements to the airbag de-icing system may specifically include improvements to the logical architecture of the airbag de-icing system or additions to the protective design.

[0043] In the aircraft airbag de-icing system safety assessment and improvement method disclosed in the above-mentioned embodiment, when conducting a safety assessment on the aircraft airbag de-icing system, consideration is given to mitigating the degree of hazard of an airbag de-icing system failure state of an intermediate hazard level according to the established emergency operations, and the hazard level of the airbag de-icing system failure state is re-determined. The result of the safety assessment is significantly different from the actual hazard level, which can effectively guide the improvement of the airbag de-icing system and obtain a reasonable and appropriate airbag de-icing system design plan.

[0044] So far, the technical solution of the present application has been described in conjunction with the preferred embodiments shown in the accompanying drawings. Those skilled in the art should understand that the scope of protection of the present application is obviously not limited to these specific embodiments. Without departing from the principles of the present application, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the scope of protection of the present application.

Claims

1. A safety assessment and improvement method for an aircraft airbag deicing system, characterized in that: include: Step 1: Conduct functional hazard analysis on the failure state of the airbag de-icing system to determine the hazard level; Step 2: Develop emergency operations for air bag de-icing system failure conditions of intermediate hazard levels; Step 3: Analyze the degree of harm caused by the failure state of the airbag de-icing system with an intermediate harm level according to the emergency operation, and redetermine the harm level of the failure state of the airbag de-icing system; Step 4: Conduct a safety assessment on the airbag de-icing system and improve the airbag de-icing system based on the assessment results.

2. The aircraft airbag deicing system safety assessment and improvement method according to claim 1, characterized in that: In step 4, if the hazard level of the airbag de-icing system failure state does not reach the intermediate or higher hazard level, there is no need to improve the airbag de-icing system.

3. The aircraft airbag deicing system safety assessment and improvement method according to claim 2, characterized in that: In step 4, if the hazard level of the airbag deicing system failure state is intermediate or above, a Markov model is constructed to calculate the probability of occurrence of the airbag deicing system failure state of intermediate or above hazard levels.

4. The aircraft airbag deicing system safety assessment and improvement method according to claim 3, characterized in that: In step 4, if the calculated probability of failure of the airbag de-icing system of intermediate or higher hazard levels is less than the probability allowed by safety, there is no need to improve the airbag de-icing system.

5. The aircraft airbag deicing system safety assessment and improvement method according to claim 4, characterized in that: In step 4, if the calculated probability of failure of the airbag de-icing system of intermediate or higher hazard levels is greater than the probability allowed by safety, the airbag de-icing system needs to be improved and steps 1 to 4 are repeated.

6. The aircraft airbag deicing system safety assessment and improvement method according to claim 5, characterized in that: Step 4: If the hazard level of the airbag deicing system failure state is intermediate or above, a Markov model is constructed to calculate the probability of the airbag deicing system failure state of intermediate or above hazard level, specifically: Define the state before the failure state of the air bag de-icing system with intermediate and higher hazard levels occurs; Determine the state before the failure state of the airbag deicing system with intermediate or higher hazard levels occurs, and the transition relationship between the failure state of the airbag deicing system with intermediate or higher hazard levels, and draw a state transition diagram; Assign the state of the airbag de-icing system before the failure state of the intermediate and above hazard level occurs, the probability of transition to the failure state of the airbag de-icing system of the intermediate and above hazard level, list the relevant differential equations, and calculate the probability of the failure state of the airbag de-icing system of the intermediate and above hazard level.

7. The aircraft airbag deicing system safety assessment and improvement method according to claim 6, characterized in that: In step 4, after determining the state before the failure state of the airbag deicing system with intermediate and above hazard levels occurs and the transition relationship between the failure state of the airbag deicing system with intermediate and above hazard levels, draw a state transition diagram.

8. The aircraft airbag deicing system safety assessment and improvement method according to claim 1, characterized in that: Improving the airbag deicing system specifically involves improving the logical architecture of the airbag deicing system.

9. The aircraft airbag deicing system safety assessment and improvement method according to claim 1, characterized in that: The improvement to the airbag de-icing system is specifically designed to increase protection.

10. The aircraft airbag deicing system safety assessment and improvement method according to claim 1, characterized in that: The hazard level of the airbag de-icing system failure state is divided according to SAE 4761, from high to low into I, II, III, IV, and V.

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