Narrative:

On takeoff from lax runway 24R at liftoff, left engine torque fluctuated approximately +/- 5 percent. No other indications to correspond at this time. Climbing through 1000 ft, torque increased fluctuation +/- 15 percent with at least +/- 1 percent RPM fluctuation and corresponding audio and yaw changes. Asked to return to lax. Landed at lax with no further problems or incidents. We explained the problem to maintenance and they took it to be worked on. 2 hours later we picked the aircraft up from maintenance and prepared to leave for sna. (Maintenance said they cleaned an oily cannon plug and ran up the engine with a good operations check.) left engine torque came up a little slower than right and slow to stabilize. Through 80 KTS, torque fluctuation appeared +/- 15 percent. Did not observe other parameters, aborted takeoff. Returned to gate and turned it over to maintenance with the same problem. They felt now it was probably the torque/temperature limiting computer, and prepared the aircraft for ferry flight to fat with ttl computer inoperative. I told local maintenance that if this did not correct the problem I was not going anywhere. 4 hours later the aircraft was set for ferry flight with ttl computer turned off. Cleared for takeoff and added power. Left torque again came up slower than right and again through 80 KTS torque fluctuations appeared +/- 15 percent. Did not observe other parameters due being busy with takeoff, aborted takeoff. Maintenance control who asked why we aborted a ferry flight. After some heated discussion, we determined that the original maintenance personnel (changed shifts by now) did not inform maintenance control about the audio and yaw problems. Maintenance control thought we were only aborting for an indication problem and not a perceived real problem. They gave us a new aircraft to complete our shift. Next day I inquired as to the status of the aircraft. The airplane was ferried up to fat the following morning where the main maintenance base replaced a fuel control valve.

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Original NASA ASRS Text

Title: COMMUTER LTT HAD AN AIR TURNBACK PLUS 2 TKOF ABORTS BEFORE BEING FERRIED TO MAINT BASE FOR REPAIR.

Narrative: ON TKOF FROM LAX RWY 24R AT LIFTOFF, L ENG TORQUE FLUCTUATED APPROX +/- 5 PERCENT. NO OTHER INDICATIONS TO CORRESPOND AT THIS TIME. CLBING THROUGH 1000 FT, TORQUE INCREASED FLUCTUATION +/- 15 PERCENT WITH AT LEAST +/- 1 PERCENT RPM FLUCTUATION AND CORRESPONDING AUDIO AND YAW CHANGES. ASKED TO RETURN TO LAX. LANDED AT LAX WITH NO FURTHER PROBLEMS OR INCIDENTS. WE EXPLAINED THE PROBLEM TO MAINT AND THEY TOOK IT TO BE WORKED ON. 2 HRS LATER WE PICKED THE ACFT UP FROM MAINT AND PREPARED TO LEAVE FOR SNA. (MAINT SAID THEY CLEANED AN OILY CANNON PLUG AND RAN UP THE ENG WITH A GOOD OPS CHK.) L ENG TORQUE CAME UP A LITTLE SLOWER THAN R AND SLOW TO STABILIZE. THROUGH 80 KTS, TORQUE FLUCTUATION APPEARED +/- 15 PERCENT. DID NOT OBSERVE OTHER PARAMETERS, ABORTED TKOF. RETURNED TO GATE AND TURNED IT OVER TO MAINT WITH THE SAME PROBLEM. THEY FELT NOW IT WAS PROBABLY THE TORQUE/TEMP LIMITING COMPUTER, AND PREPARED THE ACFT FOR FERRY FLT TO FAT WITH TTL COMPUTER INOP. I TOLD LCL MAINT THAT IF THIS DID NOT CORRECT THE PROBLEM I WAS NOT GOING ANYWHERE. 4 HRS LATER THE ACFT WAS SET FOR FERRY FLT WITH TTL COMPUTER TURNED OFF. CLRED FOR TKOF AND ADDED PWR. L TORQUE AGAIN CAME UP SLOWER THAN R AND AGAIN THROUGH 80 KTS TORQUE FLUCTUATIONS APPEARED +/- 15 PERCENT. DID NOT OBSERVE OTHER PARAMETERS DUE BEING BUSY WITH TKOF, ABORTED TKOF. MAINT CTL WHO ASKED WHY WE ABORTED A FERRY FLT. AFTER SOME HEATED DISCUSSION, WE DETERMINED THAT THE ORIGINAL MAINT PERSONNEL (CHANGED SHIFTS BY NOW) DID NOT INFORM MAINT CTL ABOUT THE AUDIO AND YAW PROBLEMS. MAINT CTL THOUGHT WE WERE ONLY ABORTING FOR AN INDICATION PROBLEM AND NOT A PERCEIVED REAL PROBLEM. THEY GAVE US A NEW ACFT TO COMPLETE OUR SHIFT. NEXT DAY I INQUIRED AS TO THE STATUS OF THE ACFT. THE AIRPLANE WAS FERRIED UP TO FAT THE FOLLOWING MORNING WHERE THE MAIN MAINT BASE REPLACED A FUEL CTL VALVE.

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.