Optimal Replacement of Safety-Critical Aircraft Parts with
Abstract: Â© 2010 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must first be obtained from the IEEE. This paper aims to propose a practical approach to solving a maintenance optimization problem with uncertain system utilizations. This problem arises when we want to determine the optimal replacement time for turbine wheels, a safety-critical part in aircraft engines, by considering both the utilization uncertainties and the fact that a fleet of engines have been operating in the field for several years. It is important to conduct the trade off analysis in order to balance the safety requirement and the maintenance cost. The proposed research will investigate the maintenance issue in the following steps: First of all, we will develop a quantitative model to estimate the uncertainties in aircraft engine utilizations. The model will be further verified based on the field data such as component and system lifetimes, repair and replacement costs. Secondly, we will propose an optimizationbased framework to minimize the maintenance cost by incorporating system utilization unce! rtainties. Finally, a Monte Carlo simulation program is developed to solve the optimization problem. Both analytical and simulation results will be compared in terms of the computational complexity and the estimation accuracy. A type of turbine engine has been installed for operation in the aircraft fleet for several years. Due to the differences in installation dates and utilization rates, each engine has accumulated different operating hours. Upon failure, the engine will be removed from the aircraft and sent to a maintenance shop for failure diagnosis and repair. Before the removal, each engineâ€™s exact operating hours is not known, but can be appropriately estimated by an average daily utilization rate. Therefore, reliabilities of turbine engines and some safety-critical components can be inferred based on the collected operating data logs.
Keywords: RAMS 2010 Proceedings - Maintainability - Reliability Analysis/Prediction/Estimation