Narrative:

We started and taxied out without any abnormality from the engine instruments. Upon our pushing the power and setting the takeoff EPR; I looked outside to maintain runway alignment as the PF. At approximately 60 KIAS; the captain called airspeed alive and I checked my airspeed indicator and the engine gauges briefly. At that moment the flight engineer pointed out that N1; N2; egt; and fuel flows didn't agree with what the EPR was on the #3 engine. The captain called for the abort and the abort was initiated between 60-70 KIAS. The airplane came to a stop easily within the remaining runway. We taxied back in to the ramp and maintenance MEL'ed the EPR gauge. We taxied back out and took off using N1 to set power per the MEL. The engine performed normally and all remaining gauges indicated the engine was at takeoff power. I was later told that maintenance worked #3 engine's EPR system but never ran it up. It was later determined that EPR line that is connected to the bullet on the JT8D engine was blocked. I am slightly concerned that with all the engine problems the company has had recently; it seems to me; as a pilot; if you worked on the engine you would run it up after completing the work to make sure it is working normally. This could have turned out a lot worse had we continued the takeoff and not recognized that #3 wasn't putting out full power. There very well could have been a similar accident to that years ago. That flight had ice blocking sensors on the engines which caused the EPR gauge system to read full power when all other indications the engine wasn't making full power. It also helps that captain listened to the engineer and also recognized that something was wrong. CRM definitely worked in this case. I feel that the FAA should look into putting out an advisory circular or airworthiness directive for aircraft using EPR. EPR should not be used as the primary method of setting power. I feel setting power by the N1 RPM is much safer.

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Original NASA ASRS Text

Title: AN ACR FO REPORTS REJECTED TKOF DUE TO LOW EPR ON CENTER ENGINE AND QUESTIONS THE EPR MEL APPLIED BY MAINTENANCE WITHOUT AN ENGINE RUN-UP.

Narrative: WE STARTED AND TAXIED OUT WITHOUT ANY ABNORMALITY FROM THE ENG INSTS. UPON OUR PUSHING THE POWER AND SETTING THE TKOF EPR; I LOOKED OUTSIDE TO MAINTAIN RWY ALIGNMENT AS THE PF. AT APPROX 60 KIAS; THE CAPT CALLED AIRSPD ALIVE AND I CHKED MY AIRSPD INDICATOR AND THE ENG GAUGES BRIEFLY. AT THAT MOMENT THE FE POINTED OUT THAT N1; N2; EGT; AND FUEL FLOWS DIDN'T AGREE WITH WHAT THE EPR WAS ON THE #3 ENG. THE CAPT CALLED FOR THE ABORT AND THE ABORT WAS INITIATED BTWN 60-70 KIAS. THE AIRPLANE CAME TO A STOP EASILY WITHIN THE REMAINING RWY. WE TAXIED BACK IN TO THE RAMP AND MAINT MEL'ED THE EPR GAUGE. WE TAXIED BACK OUT AND TOOK OFF USING N1 TO SET POWER PER THE MEL. THE ENG PERFORMED NORMALLY AND ALL REMAINING GAUGES INDICATED THE ENG WAS AT TKOF POWER. I WAS LATER TOLD THAT MAINT WORKED #3 ENG'S EPR SYS BUT NEVER RAN IT UP. IT WAS LATER DETERMINED THAT EPR LINE THAT IS CONNECTED TO THE BULLET ON THE JT8D ENG WAS BLOCKED. I AM SLIGHTLY CONCERNED THAT WITH ALL THE ENG PROBS THE COMPANY HAS HAD RECENTLY; IT SEEMS TO ME; AS A PLT; IF YOU WORKED ON THE ENG YOU WOULD RUN IT UP AFTER COMPLETING THE WORK TO MAKE SURE IT IS WORKING NORMALLY. THIS COULD HAVE TURNED OUT A LOT WORSE HAD WE CONTINUED THE TKOF AND NOT RECOGNIZED THAT #3 WASN'T PUTTING OUT FULL POWER. THERE VERY WELL COULD HAVE BEEN A SIMILAR ACCIDENT TO THAT YEARS AGO. THAT FLT HAD ICE BLOCKING SENSORS ON THE ENGS WHICH CAUSED THE EPR GAUGE SYS TO READ FULL POWER WHEN ALL OTHER INDICATIONS THE ENG WASN'T MAKING FULL POWER. IT ALSO HELPS THAT CAPT LISTENED TO THE ENGINEER AND ALSO RECOGNIZED THAT SOMETHING WAS WRONG. CRM DEFINITELY WORKED IN THIS CASE. I FEEL THAT THE FAA SHOULD LOOK INTO PUTTING OUT AN ADVISORY CIRCULAR OR AIRWORTHINESS DIRECTIVE FOR ACFT USING EPR. EPR SHOULD NOT BE USED AS THE PRIMARY METHOD OF SETTING POWER. I FEEL SETTING POWER BY THE N1 RPM IS MUCH SAFER.

Data retrieved from NASA's ASRS site as of May 2009 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.