37000 Feet | Browse and search NASA's Aviation Safety Reporting System |
|
Attributes | |
ACN | 498122 |
Time | |
Date | 200101 |
Day | Wed |
Local Time Of Day | 0601 To 1200 |
Place | |
Locale Reference | navaid : sat.vortac |
State Reference | TX |
Altitude | msl single value : 20000 |
Environment | |
Flight Conditions | IMC |
Light | Daylight |
Aircraft 1 | |
Controlling Facilities | artcc : zhu.artcc |
Operator | common carrier : air carrier |
Make Model Name | SF 340B |
Operating Under FAR Part | Part 125 |
Navigation In Use | other vortac |
Flight Phase | cruise : level |
Flight Plan | IFR |
Person 1 | |
Affiliation | company : air carrier |
Function | flight crew : first officer |
Qualification | pilot : multi engine pilot : instrument pilot : commercial pilot : cfi |
Experience | flight time last 90 days : 253 flight time total : 2641 flight time type : 1110 |
ASRS Report | 498122 |
Person 2 | |
Affiliation | company : air carrier |
Function | flight crew : captain oversight : pic |
Qualification | pilot : atp |
Events | |
Anomaly | aircraft equipment problem : critical inflight encounter : weather other anomaly other |
Independent Detector | other flight crewa other flight crewb |
Resolutory Action | controller : provided flight assist controller : issued new clearance other |
Consequence | faa : investigated faa : reviewed incident with flight crew other other |
Supplementary | |
Problem Areas | Aircraft |
Primary Problem | Aircraft |
Narrative:
After being in cruise flight for approximately 20 mins in IMC at -18 degrees C, we observed a momentary power interruption in the #1 engine, the ignition light came on and a popping noise was heard in both the cabin and the cockpit. 2-3 mins later, the same thing occurred in the #2 engine. While the #2 engine's ignition light was still on, the #1 engine's ignition light reilluminated and several more popping noises were heard. We descended to 8000 ft where the outside air temperature was above 0 degrees C. Engine operation returned to normal just after we initiated the descent and the flight continued on to its destination without further incident. Callback conversation with reporter revealed the following information: aircraft is equipped with general electric CT7-9B engines. This has been a long term problem associated with high altitude operation. This has been so much of a problem that there is an operating bulletin published. The official name for it is 'power interruption.' it occurs above 15000 ft and goes away at lower altitudes. The reporter felt that the engine actually experienced a series of flameouts. The automatic ignition circuit was triggered. This caused an immediate relight. The engine anti-ice was on at the time. The company uses no fuel additive. The company has removed and read the flight recorder. The FAA certification branch in sea, as well as the NTSB, and company has extensively debriefed the crew and flight attendants. The reporter did not know what maintenance did to sign off the crew discrepancy report.
Original NASA ASRS Text
Title: SF34 CREW HAD ENG PROBS IN ZHU CLASS A AIRSPACE.
Narrative: AFTER BEING IN CRUISE FLT FOR APPROX 20 MINS IN IMC AT -18 DEGS C, WE OBSERVED A MOMENTARY PWR INTERRUPTION IN THE #1 ENG, THE IGNITION LIGHT CAME ON AND A POPPING NOISE WAS HEARD IN BOTH THE CABIN AND THE COCKPIT. 2-3 MINS LATER, THE SAME THING OCCURRED IN THE #2 ENG. WHILE THE #2 ENG'S IGNITION LIGHT WAS STILL ON, THE #1 ENG'S IGNITION LIGHT REILLUMINATED AND SEVERAL MORE POPPING NOISES WERE HEARD. WE DSNDED TO 8000 FT WHERE THE OUTSIDE AIR TEMP WAS ABOVE 0 DEGS C. ENG OP RETURNED TO NORMAL JUST AFTER WE INITIATED THE DSCNT AND THE FLT CONTINUED ON TO ITS DEST WITHOUT FURTHER INCIDENT. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: ACFT IS EQUIPPED WITH GENERAL ELECTRIC CT7-9B ENGS. THIS HAS BEEN A LONG TERM PROB ASSOCIATED WITH HIGH ALT OP. THIS HAS BEEN SO MUCH OF A PROB THAT THERE IS AN OPERATING BULLETIN PUBLISHED. THE OFFICIAL NAME FOR IT IS 'PWR INTERRUPTION.' IT OCCURS ABOVE 15000 FT AND GOES AWAY AT LOWER ALTS. THE RPTR FELT THAT THE ENG ACTUALLY EXPERIENCED A SERIES OF FLAMEOUTS. THE AUTO IGNITION CIRCUIT WAS TRIGGERED. THIS CAUSED AN IMMEDIATE RELIGHT. THE ENG ANTI-ICE WAS ON AT THE TIME. THE COMPANY USES NO FUEL ADDITIVE. THE COMPANY HAS REMOVED AND READ THE FLT RECORDER. THE FAA CERTIFICATION BRANCH IN SEA, AS WELL AS THE NTSB, AND COMPANY HAS EXTENSIVELY DEBRIEFED THE CREW AND FLT ATTENDANTS. THE RPTR DID NOT KNOW WHAT MAINT DID TO SIGN OFF THE CREW DISCREPANCY RPT.
Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.