Gas Path Analysis as a Tool for the Predictive Maintenance of the Honeywell 331-500 Auxiliary Power Unit

This study examines Gas Path Analysis (GPA) as a method for the predictive maintenance of the Honeywell 331-500 Auxiliary Power Unit (APU). The 331-500 is used on the Boeing 777 and is susceptible to a sudden failure during operation due to the release of a first stage turbine blade. Investigations found the failure mechanisms of the blade...