FLC OF AN MLG ACR ACFT ON A FERRY FLT TO RETURN ACFT TO MAINT BASE EXPERIENCED SIMILAR ENG PROB WHICH CAUSED THE ORIGINAL OTS CONDITION AND NEED TO FERRY THE ACFT FOR MAINT. THE ACFT CONTINUED TO DEST ON REDUCED PWR UNEVENTFULLY.

Date: 1993-09 · Aircraft: Medium Large Transport; Low Wing; 2 Turbojet Eng

Anomalies: aircraft-equipment-problem-critical|other-unspecified

Synopsis

FLC OF AN MLG ACR ACFT ON A FERRY FLT TO RETURN ACFT TO MAINT BASE EXPERIENCED SIMILAR ENG PROB WHICH CAUSED THE ORIGINAL OTS CONDITION AND NEED TO FERRY THE ACFT FOR MAINT. THE ACFT CONTINUED TO DEST ON REDUCED PWR UNEVENTFULLY.

Narrative

THIS ACFT WAS FLOWN ON A PREVIOUS LEG FROM DFW-SJC AND HAD EXPERIENCED A MILD COMPRESSOR STALL ON THE R ENG DURING TKOF FROM DFW. THE ENG RECOVERED ON ITS OWN; THE AUTO THROTTLES NEVER DISENGAGED; AND THE FLT WAS CONTINUED WITH ALL ENG INDICATIONS NORMAL. AS A PRECAUTION; MAINT PERFORMED A BORESCOPE INSPECTION AND REPLACED THE PRESSURE RATIO CTL VALVE. A GND TEST RUN WAS DONE AND ABOVE 1.90 EPR THE ENG CONSISTENTLY EXPERIENCED COMPRESSOR STALLS. DUE TO LIMITED MAINT; THE COMPANY WANTED THE ACFT IN DFW TO DO AN ENG CHANGE. WE AGREED TO FLY THE ACFT ONLY AFTER INSURING ALL 'LEGALITIES' WERE INSURED. DUE TO THE LIGHT ACFT WT; NO SIGNS OF ENG DAMAGE (FROM THE BORESCOPE INSPECTION) AND NORMAL ENG PERFORMANCE BELOW 1.90 EPR; WE FELT IT WAS SAFE TO FLY BACK TO DFW. TKOF WAS PERFORMED AT REDUCED (ALTERNATE) THRUST AND CLB TO FL370 WAS NORMAL. APPROX 90 MINS INTO FLT; WITH BOTH ENGS OPERATING AT ABOUT 1.78 EPR; THE R ENG COMPRESSOR STALLED AGAIN AND ROLLED BACK TO ABOUT 1.50 EPR. THRUST ON THE R ENG WAS REDUCED; A DSCNT TO FL240 ACCOMPLISHED AND THE L ENG MAINTAINED A LEVEL CRUISE SPD OF MACH .65 AT ABOUT 1.90 EPR. WE LEFT THE ENG AT NEAR IDLE SINCE IT WAS RUNNING NORMALLY AGAIN. AFTER RADIO CONTACT WAS MADE WITH THE MAINT COORDINATOR; HE AGAIN EMPHASIZED THEIR DESIRE TO GET THE JET TO DFW. AGAINST MY BETTER JUDGEMENT; THE CAPT ELECTED TO CONTINUE THE FLT UNDER THESE CONDITIONS AND THE RETURN TO DFW WAS UNEVENTFUL. LOOKING BACK AT THE CHAIN OF EVENTS; WE PROBABLY SHOULD HAVE JUST LET MAINT TRUCK IN A NEW MOTOR; HOWEVER OUR DESIRE TO GET THE AIRPLANE 'BACK ON THE LINE' AND HELP MAINT OUT NEGATIVELY AFFECTED OUR JUDGEMENT. AFTER EXPERIENCING THE SECOND COMPRESSOR STALL ON THE FERRY FLT HOME; I SHOULD HAVE BEEN MORE FORCEFUL ABOUT LNDG THE AIRPLANE INSTEAD OF OVERFLYING 2 SUITABLE LNDG FIELDS.

Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.