Narrative:

During takeoff I observed left engine indications high (N1 above 100%, EPR rising above takeoff setting and temperatures above normal) at the 80 KT call. Reduced throttle and rechked. Engine indications again trended high. Reduced throttle twice to try to keep engine indications in limits. During climb out I asked the first officer what the left N1 RPM at map was. He said he observed a maximum of 102.8%. The pilots manual calls for a maximum of 100% on this dash number engine (JT8D-9). Contacted maintenance. They informed me that the engine readings were within limits. When I asked why our limits were lower they had no response. I informed them that I would continue to our intermediate stop (at this point of the flight we were halfway there anyway) but would not continue to the final destination without proof in writing that the limits had not been exceeded. On arrival at the intermediate stop I was informed by our mechanic that maintenance control had called and told him that the engine was in limits and sent him a facsimile showing the limits as 107.7. I phoned maintenance and discussed these limits and the fact that they varied from the flight crew limits -- they insisted that the facsimile showed the proper limits for the -9 engine, and the out-base mechanic signed the overspd write-up in the log as being in limits. We flew the aircraft to our final destination (making a reduced power takeoff). During the weekend layover I called maintenance and flight standards to see why there was such a large difference between flight crew and maintenance limits -- I got no answers. When we arrived at the aircraft, I found that maintenance had done 1 inspection and retrimed the engine. When I asked why this was done if the limits had not been exceeded, I was told it was just a precaution. I filed a debrief with flight management and have not received an answer in over a month. I suspect that maintenance control gave me and the out-based mechanic misleading information so that we would continue the flight without a maintenance delay or cancellation. If this wasn't the case there certainly should not be a difference between the flight and maintenance limits.

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Original NASA ASRS Text

Title: A COMMERCIAL FIXED WING MLG RPTED #1 ENG WENT TO 102 PT 8 PERCENT N1 SPD ON TKOF OUT OF FLT MANUAL LIMITS WHICH ARE IN CONFLICT WITH MAINT MANUAL LIMITS OF 107 PT 7 PERCENT.

Narrative: DURING TKOF I OBSERVED L ENG INDICATIONS HIGH (N1 ABOVE 100%, EPR RISING ABOVE TKOF SETTING AND TEMPS ABOVE NORMAL) AT THE 80 KT CALL. REDUCED THROTTLE AND RECHKED. ENG INDICATIONS AGAIN TRENDED HIGH. REDUCED THROTTLE TWICE TO TRY TO KEEP ENG INDICATIONS IN LIMITS. DURING CLBOUT I ASKED THE FO WHAT THE L N1 RPM AT MAP WAS. HE SAID HE OBSERVED A MAX OF 102.8%. THE PLTS MANUAL CALLS FOR A MAX OF 100% ON THIS DASH NUMBER ENG (JT8D-9). CONTACTED MAINT. THEY INFORMED ME THAT THE ENG READINGS WERE WITHIN LIMITS. WHEN I ASKED WHY OUR LIMITS WERE LOWER THEY HAD NO RESPONSE. I INFORMED THEM THAT I WOULD CONTINUE TO OUR INTERMEDIATE STOP (AT THIS POINT OF THE FLT WE WERE HALFWAY THERE ANYWAY) BUT WOULD NOT CONTINUE TO THE FINAL DEST WITHOUT PROOF IN WRITING THAT THE LIMITS HAD NOT BEEN EXCEEDED. ON ARR AT THE INTERMEDIATE STOP I WAS INFORMED BY OUR MECH THAT MAINT CTL HAD CALLED AND TOLD HIM THAT THE ENG WAS IN LIMITS AND SENT HIM A FAX SHOWING THE LIMITS AS 107.7. I PHONED MAINT AND DISCUSSED THESE LIMITS AND THE FACT THAT THEY VARIED FROM THE FLC LIMITS -- THEY INSISTED THAT THE FAX SHOWED THE PROPER LIMITS FOR THE -9 ENG, AND THE OUT-BASE MECH SIGNED THE OVERSPD WRITE-UP IN THE LOG AS BEING IN LIMITS. WE FLEW THE ACFT TO OUR FINAL DEST (MAKING A REDUCED PWR TKOF). DURING THE WEEKEND LAYOVER I CALLED MAINT AND FLT STANDARDS TO SEE WHY THERE WAS SUCH A LARGE DIFFERENCE BTWN FLC AND MAINT LIMITS -- I GOT NO ANSWERS. WHEN WE ARRIVED AT THE ACFT, I FOUND THAT MAINT HAD DONE 1 INSPECTION AND RETRIMED THE ENG. WHEN I ASKED WHY THIS WAS DONE IF THE LIMITS HAD NOT BEEN EXCEEDED, I WAS TOLD IT WAS JUST A PRECAUTION. I FILED A DEBRIEF WITH FLT MGMNT AND HAVE NOT RECEIVED AN ANSWER IN OVER A MONTH. I SUSPECT THAT MAINT CTL GAVE ME AND THE OUT-BASED MECH MISLEADING INFO SO THAT WE WOULD CONTINUE THE FLT WITHOUT A MAINT DELAY OR CANCELLATION. IF THIS WASN'T THE CASE THERE CERTAINLY SHOULD NOT BE A DIFFERENCE BTWN THE FLT AND MAINT LIMITS.

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.