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The Role of PHM at Commercial Airlines

This chapter discusses the evolution of maintenance, the goals of the various stakeholders, and the implementation and the application of prognostics and health management (PHM) at commercial airlines from its beginnings to today. While aircraft and aviation are inherently safe, PHM offers an enhancement to safety by enabling component and system failures to be predicted and prevented before the aircraft is in revenue service. PHM enables oil consumption monitoring as well as the monitoring of inflight starting of the auxiliary power unit (APU). Ever since gas turbines have become the major propulsion and auxiliary power systems on aircraft, advanced engine health management (EHM) has become a critical part of the overall PHM landscape as well. Health monitoring of the environmental control system (ECS) is a more recent PHM application at commercial airlines. Aircraft landing system health monitoring is a common practice at commercial airlines and is often referred to as wheel‐and‐brake (WB) monitoring.