Abstract:After many hardships, it has become the consensus of the domestic aviation industry that we must strive to promote the construction of the operation support capacity of civil aircraft manufacturers. As operation support is an extension of "traditional business chain" of domestic aviation manufacturing industry, although there are foreign product operation practices to learn from, it still needs more exploration and experience accumulation to achieve the ability of "knowing why" of operation support system and capacity building. Based on the long-term follow-up and limited participation in the operation practice of several domestic civil aircraft, this paper expounds the views on several problems in the operation support capacity building of domestic civil aircraft manufacturing enterprises. Firstly, the importance of "operation support technology" in the construction of "operation support capability" is analyzed; It is proposed to cultivate spare parts market through "minimum replaceable parts" decomposition to reduce cost, provide value-added service for user product operation by adding "new skills" training demand, promote manual compilation technology update and add new highlights for domestic civil aircraft operation support. It is hoped that based on the discussion of operation support capacity building of civil aircraft manufacturers, it can promote their technical development and promote the application of relevant ideas in the field of civil aircraft, so as to meet the major national needs and engineering practice.

Abstract:At present, the maintenance items in the maintenance program are all planned maintenance items made by MSG-3 analysis method, so the maintenance mode still stays in the traditional scheduled maintenance mode. This paper studies the technical conditions, methods and development process of developing the planned maintenance project into the predictive maintenance project, explores the development direction of the future maintenance theory and maintenance mode, and gives strategies and suggestions for establishing the predictive centered maintenance concept and maintenance mode based on data analysis. In addition, in view of the existing implementable solutions, this paper also verifies the method and the whole process of forwarding a planned maintenance project to a predictive maintenance project through the detailed analysis of a real aircraft system case based on methodology, which is of great significance for the practical application of predictive maintenance in the current planned maintenance project.

Abstract:Preventive maintenance is an indispensable part of civil aircraft operational support activities, and it is also the basis for ensuring the safe and economic operation of civil aircraft. As the first international general standard for preventive maintenance, S4000P provides preventive maintenance with a reasonable analysis method for the formulation of initial maintenance tasks throughout the life cycle, the analysis of unplanned maintenance tasks, and the optimization of initial maintenance tasks through operating data. To expand the application of S4000P in the field of civil aircraft, this article analyzes the S4000P, interprets the preventive maintenance business process, sorts out the life cycle preventive maintenance activities, and clarifies the business interface between S4000P and the full series of specifications based on the ASD S-series specifications, and the S4000P-based civil aircraft preventive maintenance analysis framework is established to provide strong support for advancing the development and optimization process of civil aircraft preventive maintenance.

Abstract:To ensure that safety level can be maintained within the acceptable range, civil aviation aircraft need to carry out risk assessment in the continued airworthiness stage. This paper is based on the Transport Aircraft Risk Assessment Method (TARAM) and the risk criteria, by considering different crack sizes, and giving the calculation method of fleet risk value based on the fleet fault number, critical crack and characteristic life. And taking the fatigue crack of the fuselage supercharging boundary structure as an example for ongoing safety risk assessment to calculate the risk level of the event, and the time limit of corrective action implementation. And the implementation time limit of corrective measures was validated by individual risk within time limit using corrective actions. Since the results show that the individual risk is below the risk threshold, it can be concluded that the corrective measures and implementation time limit formulated in this article meet the continuous safety requirements of the fleet and thus ensure the safe operation of the fleet.

Abstract:In order to improve the manual availability, reduce the cost and enhance the competition capability for aviation aircraft. According to the type and content of maintenance procedure, the recommendations are given for verification methods application. Based on the table-top verification method and on-object verification method from S1000D standard, this paper develops two sub-methods of daily work verification and dedicated verification for on-object verification, and proposes the evaluation/simulation verification method. There are four sub-methods belongs to evaluation/simulation verification method, which are suitable for difference situations. The verification methods are applied in civil aircraft maintenance manual development and the methods can be expanded to different technical publication program.

Abstract:Reliability evaluation during aero-engine operation is one of the key issues in the field of reliability evaluation of aero-engine, this paper proposes a method to support the evaluation of aeroengine operation reliability in the process of aircraft mission. The method is based on the characteristics of flight mission and aeroengine. Considering the current operating environment, the transient state of the aircraft, and the current working state of the engine, the quick access recorder (QAR) information is used as the analysis data to analyze the operational reliability. The proposed method combines Random Forest algorithm with stratified sampling method to fit, predict and calculate feature importance. Finally, a B737-800 flight mission from Beijing to Urumqi is taken as an example to verify the effectiveness and feasibility of the method. It solves the problem of data processing difficulty caused by large amount of data and high dimension in the process of aeroengine operation.

Abstract:Conducting accelerated test has gradually become an important way for performance analysis and life management of aviation high-performance structures (such as turbine blades). However, the reasonable and effective evaluation of accelerated test results has become a difficult problem restricting the development of accelerated test technology. Therefore, based on the existing physical mechanism methods, by constructing the quantitative relationship between microstructure characteristics and macro performance, this paper proposes an acceleration effectiveness evaluation method based on quantitative identification of micro characteristics, and systematically explains the acceleration damage and failure mechanism of turbine blades. This method uses a variety of advanced detection technologies to perform qualitative analysis and quantitative characterization of fracture morphologies, microstructures and element compositions, and takes the typical characteristics in field service as the comparison benchmark, which overcomes the main shortcomings of the existing physical mechanism methods and makes the evaluation results more accurate and reliable. The method proposed in this paper has important reference significance for improving the accuracy of performance analysis and life prediction of aviation high-performance structures.

Abstract:It is of more significance for verifying and determining candidate items of the Proposed Master Minimum Equipment List (PMMEL). This paper advanced a new PMMEL fuzzy comprehensive evaluation method of civil aircraft. First, the factors domain of fuzzy comprehensive evaluation is established by analyzing the purpose of PMMEL. Then, this paper determines the different fuzzy weights by using the analytic hierarchy process and sets up a fuzzy comprehensive evaluation model of PMMEL. The fuzzy comprehensive evaluation results will be obtained. Finally, this paper chose a PMMEL candidate project of the civil aircraft main landing gear downlock spring as an example. This study shows that the new PMMEL evaluation method combined with the expert-based evaluation and essential fuzzy analysis is feasible and accurate which can accurately get the clear result of whether the candidate project is allowed to be included in PMMEL and provides the analysis result verification for the traditional PMMEL method. It has important value and bright prospects for application.

Abstract:According to the requirements of AC-91-037, only after Proposal Master Minimum Equipment List (PMMEL) item has been validated and passed the evaluation of FOEB, the item will be considered to be approved by FOEB. In order to select suitable PMMEL items to validation, it is necessary for the main manufacturer of civil aircraft to comprehensively consider each influencing factor and conduct a scientific and effective evaluation of each factor. This paper establishes the PMMEL validation evaluation standard based on the analytic hierarchy process (AHP). The Delphi method is used to determine the key indicators and the importance scores of each indicator, and then the application of evaluation standards is explained through the PMMEL items about Fuel system of one domestic civil aircraft model. The results show that the PMMEL validation evaluation standard can evaluate PMMEL validation effectively, and provide reference and support for PMMEL validation.

Abstract:For the perpose of guarantee the normal take-off of aircraft, improve the operating income of airline companies and reduce the cost of aviation material guarantee, to address the problem that it is difficult to forecast aviation material consumption with small sample size and large variation, a time series-based support vector machine regression material consumption forecast model is proposed, and grid search is used to find the optimization of model parameters. Taking the actual consumption data of a domestic civil aircraft as an example, the forecast accuracy of the support vector machine regression method is verified, and the results prove that the method has good adaptability to small sample data and has higher forecast accuracy compared with the exponential smoothing method.

Abstract:This paper puts forward the technical requirements, operation process and implementation points of manual verification operation based on large number of maintenance manual operation verification work, which combined with the flight test modification work. Taking the aircraft maintenance manual verification procedure of flap high lift system and flap structural components as an example, this paper carries out the manual verification plan arrangement and verification implementation method design from the perspective of practical operation feasibility and time saving. The key elements of the verification plan and design of practical operation process are given. The key operate points and precautions for greater difficulty flap removal and installation programs are given as example, and the summary of common maintenance problems and improvement methods are recommended. All these work put forward suggestions for the follow-up verification work.

Abstract:In order to solve the problem of reliability, safety and testability of aviation equipment, there are a lot of repetitive work in engineering application, such as repetitive FMEA. However, there are many management and technical problems in traditional FMEA, and the function and hardware FMEA method given in GJB / Z 1391-2006 also has some technical defects, which leads to poor application effect of FMEA, and even many real field faults can not be analyzed by traditional FMEA. This paper starts from the perspective of system engineering, fully combines with the product development process, Taking the product function as the input of the general quality characteristics, based on the function fault logic modeling analysis, and the case application of the flight control system can effectively avoid duplication of work and solve the "two skin" problem.

Abstract:Hinge mechanism is a widely used motion mechanism in civil aircraft. The reasonable maintenance interval plays an important role in ensuring the safety and economic operation of aircraft. In order to ensure the rationality of the maintenance interval of hinge mechanism, the maintenance interval of hinge mechanism is proposed based on MSG-3. Firstly, the relevant contents of MSG-3, airworthiness provisions and national military standards are analyzed in detail, which provides the basis for the reasonable formulation of maintenance interval of hinge mechanism. Secondly, the influencing factors of maintenance interval are analyzed, and a relatively complete method and process of making maintenance interval of hinge mechanism are determined. Finally, taking the maintenance interval of flap hinge mechanism of a certain type of aircraft as an example, the feasibility of this process and method is verified, and the maintenance interval of the hinge mechanism is determined, that is, the inspection threshold and repeated inspection interval of accidental damage and environmental damage are 5 calendar years, the inspection threshold of fatigue injury is 24000 FH, and the repeated inspection interval is 14400 FH. The proposed method can provide support for the reasonable formulation of aircraft maintenance interval and maintenance program.

Abstract:In order to improve the screening efficiency of domestic civil aircraft performance monitoring parameters, a method based on improved sliding time window is proposed to screen stable cruise parameters. Unscented Kalman filter (UKF) introduces sage husa noise estimator, constructs adaptive unscented Kalman filter (AUKF), and uses AUKF to denoise QAR data; The selection standard of cruise parameters is determined, the recursive algorithm improves the sliding time window algorithm and realizes the selection of cruise parameters, and the GUI develops the parameter selection system to further improve the efficiency of parameter selection. Through the sample data of domestic ARJ21 aircraft, the results showed that AUKF can improve the reliability of data, and the improved sliding time window algorithm can improve the screening efficiency by about 50%. The research can provide reliable and efficient data selection algorithm basis for domestic civil aircraft performance monitoring parameter selection.

Abstract:To resolve the lack of rational and ?exible calculation problem of spare parts price for domesticcivil aircraft, this paper studies the pricing of spare parts from different dimensions, by synthesizing the effects of various factors, obtains the decomposition structure model of sales expenses of different types of spare parts is obtained. Firstly, the components of civil aircraft spare parts cost are elaborated. Then, the influencing factors of spare parts price are analyzed from the perspective of life cycle. Finally, the decomposition structure model of sales expenses of domestic civil aircraft is established with different spare parts in the life cycle. The research results comprehensively investigate the influencing factors of spare parts price of domestic civil aircraft models, and provide support for the establishment of spare parts sales price.

Abstract:Technical publication structuralization is the premise of realizing the interactive electronic technical publication (IETP) of aircraft. Based on S1000D standard, this paper puts forward the structural design idea of aircraft technical publication. The overall flow of the structured method is given, the detailed process of each step of the structured method discussed, the coding design of the data module of the technical publication emphasized, and the coding example is given. The research on the structuring method of technical publications provides a precondition for the standardization and internationalization of the technical publications of aircraft.

Abstract:It is very important for the economic operation of civil aircraft to make reasonable procurement and configuration of aviation materials between multi-terminals. The theoretical algorithm content formed by the research of aviation material prediction and configuration is relatively complex. In order to promote the effective application of these algorithm programs, based on the Java language, and the algorithm programs written in Matlab and Python are integrated, a multi-language hybrid programming system platform for the prediction and configuration of civil aircraft is developed. Firstly, it introduces the support vector machine algorithm and marginal analysis algorithm integrated in the system platform, and describes the implementation of hybrid programming. Then, the details of the system platform design are expounded, and the implementation of hybrid programming and the conversion method of different types of programming language’s parameter are explained. Finally, the system platform functions are tested with the actual engineering data. The use of tests shows that the platform's human-machine interface is friendly and easy to operate, and it can better realize the functions of aviation material prediction and aviation material configuration, which can provide reference and ideas for the relevant theoretical algorithm to meet the engineering needs through platform technology.

Abstract:With the development and application of Civil aircraft, the demand for the development and application of aero-engine has gradually emerged. In order to improve the dispatch reliability of aero-engine, it is necessary to conduct professionalab analysis about maintenance engineering , and promote the development and application of the service products with information-based and standardized methods. Firstly，this paper introduce the background and industry development about maintenance engineering analysis of aero-engine. The core module functions and development requirements about system are clarified based on engine maintenance engineering analysis and related standards and specifications. Then, the system of maintenance engineering analysis was developed, and the operability of the system was verified by using the engine combustion control system as a case. With the construction and use of the system, the analysis of maintenance engineering of engine will be much more standardized ,and laid an important data foundation for later design optimization and engineering analysis iteration.

Abstract:Based on the characteristics of the emergency door on the wing of a civil aircraft, and its fault has a certain concealment, so it is particularly important to analyze its safety reasonably. The evaluation and selection principles of the latent failure of the emergency door are defined, and the exposure time of the latent failure is considered in the calculation of the failure probability of the bottom event. In addition, the fault tree of accidental opening of emergency door in flight is established. The bottom event of "the latch axis movement being not in place caused by tolerance accumulation", which is generally constructed, is considered as the mechanism movement is not in place caused by the joint action of tolerance accumulation and structural wear, which the modeling technology of bottom event is refined, and the reliability model is established in accordance with the engineering practice. The results of safety analysis before and after fault tree refinement are compared. The results show that the refined fault tree is more in line with the engineering practice and the safety analysis result of emergency door is more accurate.

Abstract:Level of repair analysis (LORA) is an important part of maintenance engineering analysis for amphibious aircraft wading structures. There are many researches mainly focusing on LORA of civil aircraft, shipboard aircraft, vehicles, ships and so on in the domestic and overseas, while researches on LORA of amphibious aircraft wading structure are few. Based on this, this paper studies the process and method of LORA for the wading structure of amphibious aircraft. In this paper, a three-level repair model of the wading structure is established. The LORA process of the wading structure is proposed. An economical LORA (ELORA) model for three-level repair of wading structures is established, and the cost factors to be considered for ELORA are given. Finally, the approach switch on the wading cabin door of an amphibious aircraft is taken as an example to carry out ELOR, the calculation results demonstrate the engineering suitability of the proposed method in LORA.

Abstract:A safe, comfortable, economical and beautiful cabin can provide good aboard experiences for passengers. This will enhance the market competitiveness of domestic commercial aircrafts. By studying foreign successful experience and the development of aircraft cabin industrial design, there are four elements of it to be analyzed and three design methods are introduced. According to the trend of aviation market, this paper seeks a balance between the economy and comfort of the cabin，then determines the appropriate number of guest seats number of guest seats and cabin seating layout. Adopting kansei engineering design method and virtual reality design method，it also designs cabin interior space and board equipment from the view of safety, passenger demands, CMF and the airlines. An example is given to design a wide-body aircraft cabin and the design methods are verified. These will provide the theoretical basis and design reference for the jetliner in development.