N751XJ

ATA 2150

WHILE IN CRUISE FLIGHT AT FL450 THE FLIGHT CREW RECEIVED A MASTER CAUTION AMBER CAS CABIN PAC O’TEMP MESSAGE. THEY RAN THE PILOTS CHECKLIST FOR AMBER MESSAGES PROCEDURES AND FOLLOWED THE PROCEDURE CABIN PAC O’TEMP. THE PAC TEMPERATURE COOLED TO AN ACCEPTABLE LEVEL AND THE PROCEDURE APPEARED TO SOLVE THE CABIN PAC O’TEMP PROBLEM. APPROXIMATELY TWO MINUTES LATER, THE CREW RECEIVED A COCKPIT PAC O’TEMP AMBER CAS MESSAGE IMMEDIATELY FOLLOWED BY ANOTHER AMBER CABIN PAC O’TEMP MESSAGE. THE CREW INITIATED AN EMERGENCY DESCENT BECAUSE THEY WERE LOSING PRESSURIZATION. PASSENGER OXYGEN MASKS WERE DONNED. SHORTLY AFTER, THE CREW RECEIVED THE AMBER CAS MESSAGE CABIN ALTITUDE. THE FLIGHT CREW THEN DONNED THEIR OXYGEN MASKS. THE CREW THEN RECEIVED THE RED MASTER WARNING CAS CABIN ALTITUDE MESSAGE FOLLOWED BY THE AMBER CAS BAGGAGE ALTITUDE MESSAGE. THE COPILOT PERFORMED THE PILOT CHECKLIST EMERGENCY PROCEDURE FOR EMERGENCY DESCENT. THE CREW ELECTED TO DIVERT INTO ABQ WHERE A SAFE LANDING WAS ACCOMPLISHED. MAINTENANCE WAS SECURED TO INSPECT AND REPAIR THE AIRCRAFT. THE COCKPIT AIR CYCLE MACHINE (P/N 1013581-1) WAS FOUND TO HAVE SEIZED. THE ACM WAS REPLACED, OPERATIONAL CHECKS COMPLETED SATISFACTORILY AND THE AIRCRAFT RETURNED TO SERVICE.

ATA 2170

ON APPROACH, THE CAPTAIN'S FOOT WELL FILLED WITH A MIXTURE OF WHAT APPEARED TO BE THICK SMOKE AND VAPOR. THE EMISSION HAD AN ODOR OF BURNED DUST AND MILDEW. AS THE PILOT ADVANCED THE THRUST LEVERS TO APPROACH POWER, THE EMISSION DISCONTINUED. ON LANDING, THE CAPTAIN'S FOOT WELL FILLED AGAIN. ONCE ON THE GROUND AND ENGINES SHUT DOWN, THE EMISSION DISSIPATED. THE CREW CONDUCTED TROUBLESHOOTING, MULTIPLE ENGINE RUNS WERE ACCOMPLISHED AND THE PROBLEM RETURNED EACH TIME. MAINTENANCE WAS UNABLE TO DETERMINE THE SOURCE OF THE PROBLEM. MAINTENANCE TECHNICIANS WERE SECURED TO INSPECT AND REPAIR THE AIRCRAFT. TECHNICIANS REPORTED THAT THE SMOKE WAS INDEED WATER VAPOR. AN ASPIRATOR TEST WAS PERFORMED WITH NO FAULTS NOTED AND MOISTURE SEPARATOR DRAIN LINES VERIFIED TO BE CLEAR. COALESCER SOCKS AND RELIEF VALVES WERE CLEANED AND REINSTALLED. OPS CHECKS REVEALED THE EXISTING CONDITION. EXISTING COALESCERS SHOW EXCESSIVE WEAR. ON FURTHER TROUBLESHOOTING, IT WAS DETERMINED THAT WHAT APPEARED TO BE SMOKE WAS INDEED EXCESSIVE CONDENSATION CAUSED BY DETERIORATED WATER SEPARATOR COALESCER SOCKS (P/N: 746451-3). BOTH THE LH & RH COALESCER SOCKS WERE REPLACED WITH NEW; LEAK AND FUNCTIONAL TEST WAS NORMAL, WITH NO FURTHER DISCREPANCIES NOTED. AIRCRAFT WAS RETURNED TO SERVICE.