Study On Maintenance Decision Of Aircraft Systems Based On Reliability Data

Aircraft maintenance plays an important role in keeping healthy sustained development of civil aviation industry. Aircraft maintenance decision is not only critical to flight safety, but also have an important influence on both flight punctuality rate and aircraft operating costs.Maintenance program is a key document to guide the operation of aircraft maintenance, which is formulated based on MPD. Customized maintenance decision is subject to many factors,such as operating environment, daily utilization, maintenance ability. Accordingly,maintenance decision is a dynamic optimization process.The method of identifying maintenance signification item(MSI), the effect of failure and reasonable maintenance tasks are presented, proceed from the formation, purpose and contents of maintenance program. Establish the optimization process of the system parts of maintenance program, based on reliability data analysis method. It includes seven steps which is data preprocessing, data distribution exploration, data distribution analysis, engineering analysis, engineering conclusion, engineering verification and corrective measures. Following this optimization process, a proper method is proposed to identify data distribution and estimate its parameters. For the non-safety items, the optimal maintenance interval, which must meet the system reliability requirement, is obtained from minimum maintenance cost model. For the items which may be related to task change, to estimate whether the existing task is acceptable according to calculating the remaining effective working time. Taking the heat exchanger and precooler control valve of the mainstream B737 NG systems as examples,the result which is obtained from the reliability analysis method is in accordance with the actual work experience. It has practical significance for airlines to make maintenance decision by scientific and quantitative optimization model. In addition, for those components which have more than one part number, the method of choosing the best part number component is given, which provides grounds for product selection.