Maintenance Interval Determining Model Of Civil Aircraft Structure Based On Utilization Ratio Comprehensive Evaluating

With the development of civil aviation industry,the number of civil aircraft fleet is rapidly increasing,and the improvement of civil aircraft maintenance engineering capacity has also become the key problem urgently needed to be solved.As one of the key contents of aircraft maintenance program,great influence appear different utilization ratio.Therefore,it is urgent to study the impact of utilization ratio comprehensive evaluation on maintenance interval,and then study the technology of determining maintenance interval of civil aircraft,so as to provide theoretical basis and reference for the establishment of maintenance interval.Based on the study of utilization comprehensive evaluation,the determination of maintenance interval is studied in the initial structural maintenance program.Based on the environmental damage,which is one of the sources of structural damage,a model base on utilization ratio comprehensive evaluation is proposed.Further,a model for determining maintenance intervals of civil aircraft structures with low utilization rate under coating corrosion based on coating corrosion is proposed.Among them,the first maintenance interval determining model analyzes the sensitivity of the impact indicators under different aircraft utilization ratio through the comprehensive comparative analysis of the normal utilization ratio and the low utilization ratio.In order to ensure the accuracy of establishing the maintenance interval of civil aircraft structure,the combination of order relation analysis method and attribute importance degree is used to evaluate the index weight.The grey relation analysis method is used to verify the correlation between the evaluation value and the ideal value of each index.The maintenance interval determining model considering the comprehensive utilization ratio is established.Furthermore,the model of determining the maintenance interval of civil aircraft based on the coating corrosion is comprehensively considering the characteristics of multi-attributes,ambiguity and dynamics of protective coating system damage,it is difficult to perform single-item rating and quantify the degree of damage.A fuzzy comprehensive method is proposed to evaluate the corrosion damage level.The damage degree is determined by ridge distribution membership function,and a model for determining the corrosion maintenance interval of low utilization aircraft structure coating was established.Finally,the effectiveness of the model is verified by case analysis.On the one hand,the model can effectively solve the problem that the utilization ratio is not enough when the maintenance interval is determined in the initial structural maintenance program.On the other hand,it can provide some reference for checking the effectiveness of the coating,determining the corrosion maintenance interval and maintenance scheme.