What was found
FLIGHT DIVERTED DUE TO LOST RIGHT PACK. FOUR UNITS WERE REMOVED DUE TO THIS EVENT: HIGH PRESSURE SHUTOFF VALVE AND PRESSURE REGULATING VALVE (HPSOV/PRV, P/N: 790270-4/-14), HIGH PRESSURE CONTROLLER (HPC, P/N: 773289-15) AND PRESSURE REGULATING VALVE CONTROLLER (PRC, P/N: 792755-16). THERE WERE NO FAULTS FOUND ON HPSOV AND PRV. HPC REPAIRED DUE TO BELLOWS FAILURE, WORN BUSHINGS, DAMAGED DIAPHRAGM, BITE PRESSURE SWITCH FAILURES AND DIFFERENTIAL SWITCH FAILURE, WHICH WAS CONSIDERED TO BE THE PRIMARY FAILURE OF THE UNIT. PRC WAS REPAIRED DUE TO SCREW AND ORIFICE DAMAGES.