Incident at EDMONTON INTL AB (CYEG)
2005-02-08: UPDATE Maintenance and Manufacturing advised that MPE 446 was delayed due to an equipment switch, after A/C 584 had an A.P.U fire. A/C 552 had to be re-configured to replace it. Edmonton maintenance has been working all weekend to rectify the damage on A/C 584 due to the A.P.U fire and the A/C is still in the Edmonton hangar. There may be more information after the work is concluded and the A/C 584 is returned to service, but at this time the cause of the fire is not known or the extent of the damage. The company DOM has advised that the APU has been removed and is being held for further investigation. The DOM has been in contact with the TSB Edmonton office. More information has been requested and will be provided when it becomes available. The company has been advised to submit a required SDR.
2005-02-07: MPE 446, a B737-200, was parked on the ramp at Edmonton and Tower personnel observed smoke coming from the back of the aircraft. Emergency personnel were summoned and by the time they arrived at the aircraft, the smoke was now flames. Company employees working around the aircraft evacuated the area and the flames were extinguished by emergency personnel. No other aircraft were affected and no personnel were reported injured during the occurrence.
2005-02-11: UPDATE TSB advised that the Canadian North Boeing 737-200, C-GDPA, was on the terminal ramp at Edmonton Intl (CYEG) in preparation for flight MPE 446 to Yellowknife. Four crew members and no passengers were on board. During APU start, the APU overheat caution light illuminated and the start was aborted. The EGT continued to rise, and black smoke was seen emanating from the area of the APU tailpipe. The crew then discharged the APU fire extinguishing bottle, shut off all electrical power and evacuated the aircraft. When maintenance personnel gained access to the APU, a small amount of flame existed, which was extinguished by ARFF. There was no structural damage to the aircraft. The sequence of events leading to the fire have not been determined. A crack was found in the combustion plenum, and the fuel heater check valve, which was located directly above the crack, was leaking fuel through a failed O-ring. There was no APU fire warning indication in the cockpit, likely due to heat distress and shorting of the canon plug leading to the tail-pipe fire detection loop. The APU will be sent to an overhaul shop for inspection, and disassembly for possible TSB lab examination.
2005-03-18: UPDATE Maintenance and Manufacturing, in a follow-up report from Boeing, the aircraft manufacturer, indicated that 'IT IS FELT THAT THE FIRE WAS NOT CAUSED BY THE APU BUT BY A LEAKING FITTING ON THE APU FUEL HEATER. BURN MARKS INDICATE THAT THE FUEL LEAKED ON TOP OF THE PLENUM THEN IGNITED AS IT RAN DOWN THE SIDES AND THE SECTION BEHIND THE EXHAUST BAFFLE. THE FLAMES REACHED THE BOTTOM OF THE APU AND BURNED AND SHORTED THE FIRE DETECTION LOOP WIRING. THE FLAMES WERE DRAWN INTO THE EXHAUST AREA AND CAUSED THE EGT TO RISE. THE APU WAS TORN DOWN AT APU SHOP IN LOS ANGELES IN THE PRESENCE OF THE OPERATOR, FAA, AND GARRETT REPRESENTATIVES. ALL INSPECTED COMPONENTS OF THE APU SHOWED NORMAL WEAR AND THERE WAS NO EVIDENCE OF ANY CONDITION WHICH WOULD ACCOUNT FOR THE APU CAUSING THE FIRE.'
|Occurred At||- 18:05|
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Aircraft Details (1 aircraft)
|Canadian Registration||| Flightaware (Registration) | Flightaware (Tracking) | AvHerald|
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