Monte Carlo simulation based time limited dispatch analysis with the constraint of dispatch reliability for electronic engine control systems

Time Limited Dispatch (TLD) allows a degraded redundant system to operate for a limited length of time before repairs are required. Existing TLD analysis methods do not consider the requirement of dispatch reliability as a constraint, thus unacceptable flight delays or cancellations may occur when aircraft are dispatched following the intervals determined by existing methods. In this paper, an improved TLD analysis method with constraints of both dispatch reliability and average safety levels is proposed for Electronic Engine Control System (EECS) based on Monte Carlo simulation. Dispatch strategies for multiple fault TLD models are presented, maintenance strategies for multiple fault TLD models are discussed, and a step by step procedure of Monte Carlo simulation based TLD analysis is proposed. Finally, a case study illustrates the effectiveness of the proposed method, and a TLD analysis of an EECS is given to show the application of our method to a practical system.