Aircraft lifecycle cost-benefit analysis of PHM systems

Abstract

The use of prognostics and health management (PHM) systems can improve operational reliability by reducing delays and cancellations caused by unscheduled maintenance events and no-fault-founds (NFFs). While PHM systems have no influence on components’ failure distributions, they can improve the operational reliability of an aircraft. This is achieved by performing maintenance tasks prior a component failure based on the remaining useful life (RUL) predicted by the PHM system and by reducing NFFs based on health monitoring information of the PHM system. This study presents an analysis of the monetary potential of an improved operational reliability and reduced maintenance costs realized by the use of a PHM system. Therefore an aircraft lifecycle cost-benefit approach is chosen to conduct an economic assessment from an airline perspective. By modeling the aircraft operation based on a weekly flight plan and the maintenance simulated as discrete events within the aircraft life-cycle it is possible to analyze the influence of changes in operational reliability on aircraft utilization and the net benefit for the operator. To show the potential benefits of PHM systems within different aircraft systems (ATA-Chapters) a parameter variation of a notional aircraft system has been performed on a 150-seat short-range aircraft. Effects based on PHM have been modeled by a variation of mean times to repair (MTTR), mean times between unscheduled removals (MTBUR) and the aircraft price. The results show the monetary potential for an airline, depending on the increase of investment cost, and reduction of NFFs and repair time of the chosen system.