Reliabiliy Research Of Civil Aircraft Engine Components Based On Survival Analysis

Aircraft engine is the most important part of civil aviation aircraft. Engine components are significantly related to engine's performance, and affect the whole airplane's performance. Estimating the parameters of reliability accurately and efficiently, we can not only judge status of single component and maintain it properly, but also know the overall trend of reliability and make maintenance plans properly.This article sorts out, calculates and analysis the engine components life data of a certain airline. Relying on data, this research makes use of non-parametric method of survival analysis. First of all, based on previous studies, by the way of survival analysis,algorithms of three kinds of parameter estimation were designed. Non-parametric method such as Kaplan-Meier product limit estimation, kernel density estimation were used. Then,usage and maintenance records of engine components from a certain airline were sorted out,removing redundant and incorrect data. Typical components were selected and every record was marked censored or death. Next, using algorithms of estimation of three kinds parameters, every typical component data was calculated. Then, combined with records of maintenance and failure, trends of reliability changing and its reasons were analyzed.Finally, using MATLAB and C# language, estimation calculation program was compiled.The results of analysis show: Components, whose faliure type is early failure, consist of special materials or pneumatic parts. Plug igniter and high pressure valve are of this type.Components whose failure type is wearout failure, are usually hydraulic components, such as fuel metering unit and hydraulic pump component. Components which is type of random failure, consist of electrical and control parts. Fuel metering unit and starter are of this type.One kind of component could be of two or more types of failure. In addition, overall quality of maintenance should be improved.According to the results of calculation and analysis, estimation algorithm can describe change of reliability accurately. Its applicability, convenience of usage makes it an important technical support of maintenance plan.