Development of diagnostic and prognostic technologies for aerospace health management applications

Effective aerospace health management integrates component, subsystem and system level health monitoring strategies, consisting of anomaly/diagnostic/prognostic technologies, with an integrated modeling architecture that addresses failure mode mitigation and life cycle costs. Included within such health management systems will be various failure mode diagnostic and prognostic (D/P) approaches ranging from generic signal processing and experience-based algorithms to the more complex knowledge and model-based techniques. While signal processing and experienced-based approaches to D/P have proven effective in many applications, knowledge and model-based strategies can provide further improvements and are not necessarily more costly to develop or maintain. This paper describes some generic prognostic and health management technical approaches to confidently diagnose the presence of failure modes or prognose a distribution on remaining time to failure. Specific examples of D/P strategies are presented that include Auxiliary Power Unit (APU) fuel system valves, APU performance degradation and hot section lifing, Power Take Off (PTO) shaft and AMAD snout bearing.