Narrative:

The flight was progressing normally until the aircraft reached FL200. This was where the first indications of engine problems with the right engine were encountered. The first indication was a fluctuation of N1. After this was noted, N2 and fuel flow indications were also becoming erratic. I immediately consulted my first officer on the indications and a probable course of action. After a few seconds, the fluctuations were becoming more erratic (+/-5 to 7% N1, +/-3 to 5% N2, and +/-300 pounds fuel flow) and were progressively getting worse. I told my first officer to refer to the QRH for this problem while I tried to adjust the power setting on the right engine. There was no response. Approximately 3 seconds later, an uncommanded yawing sensation was felt by myself, and I would later find out on the ground by the flight attendant as well. At this point, myself and my first officer decided the best course of action would be to return to the originating airport since my first officer could not find a procedure for engine fluctuations in our QRH and I have never seen this condition before in training or while flying on the line. During the return, I was communicating through ACARS to both company dispatch and maintenance control of our condition and situation. Also, ATC was alerted to our situation. No emergency was declared, however, ATC was fully notified of our situation, condition, and intentions. In the descent, the fluctuations subsided but were still there until the engine speed was below 60% N1. Maintenance control sent a message back to turn off our engine speed switches and to proceed with the flight under our MEL procedures. When we received this message, we were already close to final approach and made the decision to land and sort the situation out on the ground. We landed and taxied into the ramp area with no further incident. The first officer and I stayed behind to work with our contract maintenance provider to try to troubleshoot what the problem was. We stayed to perform engine run-ups with contract maintenance while he was in communication with our maintenance control center. It was his opinion that our airline maintenance personnel should come out to look, at the engine in question. Since I had little sleep the night before, added stress from a possible critical situation, and close to 15 hours on duty, I forgot to make an entry in the aircraft maintenance log. We went back to the hotel to get some rest. We were contacted by crew scheduling later that afternoon. They told us that maintenance had been out to the aircraft a second time and that they could not duplicate the problem on the ground and that the aircraft was ok to repos. We then reported back to the aircraft, which had a write-up and action taken to clear the aml, and contacted maintenance control to put together a plan we would use if the problem recurred. Maintenance control said that it would probably be an ecu problem and to turn off the engine speed switches. The first officer and I consulted the QRH for a procedure to accomplish this and came up with the procedure for uncommanded deceleration (abnormal procedures, page ab 1-11). We departed gsp that evening with everything normal. Once again, during the climb out through 16500 ft MSL, the problem came back for about 5 seconds then became steady at FL230 (+/-5% N1, +/-3% N2, +/-200 pounds fuel flow). We then accomplished the QRH procedure then climbed to our final altitude. No further problems were encountered and a write-up of the problem was made and presented to maintenance. Supplemental information from acn 636463: discussions between the flight crew and the chief pilot took place. The chief pilot's statement was that we should have entered a holding pattern and tried to diagnose the problem in the air. He further cited the procedure for 'uncommanded engine deceleration' in the crj-200 QRH. However. We experienced fluctuations consisting of both accelerations and decelerations, which clearly could not be classified as an engine deceleration. There is no existing QRH procedure for this type of abnormality. Additionally, I never received training that addressed this type of issue. Therefore, due to the absence of this type of training and left with no checklist to follow that addressed the problem, the crew was forced to use good judgement and execute a safe return to the airfield.

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Original NASA ASRS Text

Title: RETURN LAND BY A CARJ FLT CREW MANDATED WHEN THE R ENG STARTS TO FLUCTUATE WITH NO AREAS OF THE QRH REFING THIS SYMPTOM.

Narrative: THE FLT WAS PROGRESSING NORMALLY UNTIL THE ACFT REACHED FL200. THIS WAS WHERE THE FIRST INDICATIONS OF ENG PROBS WITH THE R ENG WERE ENCOUNTERED. THE FIRST INDICATION WAS A FLUCTUATION OF N1. AFTER THIS WAS NOTED, N2 AND FUEL FLOW INDICATIONS WERE ALSO BECOMING ERRATIC. I IMMEDIATELY CONSULTED MY FO ON THE INDICATIONS AND A PROBABLE COURSE OF ACTION. AFTER A FEW SECONDS, THE FLUCTUATIONS WERE BECOMING MORE ERRATIC (+/-5 TO 7% N1, +/-3 TO 5% N2, AND +/-300 LBS FUEL FLOW) AND WERE PROGRESSIVELY GETTING WORSE. I TOLD MY FO TO REFER TO THE QRH FOR THIS PROB WHILE I TRIED TO ADJUST THE PWR SETTING ON THE R ENG. THERE WAS NO RESPONSE. APPROX 3 SECONDS LATER, AN UNCOMMANDED YAWING SENSATION WAS FELT BY MYSELF, AND I WOULD LATER FIND OUT ON THE GND BY THE FLT ATTENDANT AS WELL. AT THIS POINT, MYSELF AND MY FO DECIDED THE BEST COURSE OF ACTION WOULD BE TO RETURN TO THE ORIGINATING ARPT SINCE MY FO COULD NOT FIND A PROC FOR ENG FLUCTUATIONS IN OUR QRH AND I HAVE NEVER SEEN THIS CONDITION BEFORE IN TRAINING OR WHILE FLYING ON THE LINE. DURING THE RETURN, I WAS COMMUNICATING THROUGH ACARS TO BOTH COMPANY DISPATCH AND MAINT CTL OF OUR CONDITION AND SIT. ALSO, ATC WAS ALERTED TO OUR SIT. NO EMER WAS DECLARED, HOWEVER, ATC WAS FULLY NOTIFIED OF OUR SIT, CONDITION, AND INTENTIONS. IN THE DSCNT, THE FLUCTUATIONS SUBSIDED BUT WERE STILL THERE UNTIL THE ENG SPD WAS BELOW 60% N1. MAINT CTL SENT A MESSAGE BACK TO TURN OFF OUR ENG SPD SWITCHES AND TO PROCEED WITH THE FLT UNDER OUR MEL PROCS. WHEN WE RECEIVED THIS MESSAGE, WE WERE ALREADY CLOSE TO FINAL APCH AND MADE THE DECISION TO LAND AND SORT THE SIT OUT ON THE GND. WE LANDED AND TAXIED INTO THE RAMP AREA WITH NO FURTHER INCIDENT. THE FO AND I STAYED BEHIND TO WORK WITH OUR CONTRACT MAINT PROVIDER TO TRY TO TROUBLESHOOT WHAT THE PROB WAS. WE STAYED TO PERFORM ENG RUN-UPS WITH CONTRACT MAINT WHILE HE WAS IN COM WITH OUR MAINT CTL CTR. IT WAS HIS OPINION THAT OUR AIRLINE MAINT PERSONNEL SHOULD COME OUT TO LOOK, AT THE ENG IN QUESTION. SINCE I HAD LITTLE SLEEP THE NIGHT BEFORE, ADDED STRESS FROM A POSSIBLE CRITICAL SIT, AND CLOSE TO 15 HRS ON DUTY, I FORGOT TO MAKE AN ENTRY IN THE ACFT MAINT LOG. WE WENT BACK TO THE HOTEL TO GET SOME REST. WE WERE CONTACTED BY CREW SCHEDULING LATER THAT AFTERNOON. THEY TOLD US THAT MAINT HAD BEEN OUT TO THE ACFT A SECOND TIME AND THAT THEY COULD NOT DUPLICATE THE PROB ON THE GND AND THAT THE ACFT WAS OK TO REPOS. WE THEN RPTED BACK TO THE ACFT, WHICH HAD A WRITE-UP AND ACTION TAKEN TO CLR THE AML, AND CONTACTED MAINT CTL TO PUT TOGETHER A PLAN WE WOULD USE IF THE PROB RECURRED. MAINT CTL SAID THAT IT WOULD PROBABLY BE AN ECU PROB AND TO TURN OFF THE ENG SPD SWITCHES. THE FO AND I CONSULTED THE QRH FOR A PROC TO ACCOMPLISH THIS AND CAME UP WITH THE PROC FOR UNCOMMANDED DECELERATION (ABNORMAL PROCS, PAGE AB 1-11). WE DEPARTED GSP THAT EVENING WITH EVERYTHING NORMAL. ONCE AGAIN, DURING THE CLBOUT THROUGH 16500 FT MSL, THE PROB CAME BACK FOR ABOUT 5 SECONDS THEN BECAME STEADY AT FL230 (+/-5% N1, +/-3% N2, +/-200 LBS FUEL FLOW). WE THEN ACCOMPLISHED THE QRH PROC THEN CLBED TO OUR FINAL ALT. NO FURTHER PROBS WERE ENCOUNTERED AND A WRITE-UP OF THE PROB WAS MADE AND PRESENTED TO MAINT. SUPPLEMENTAL INFO FROM ACN 636463: DISCUSSIONS BTWN THE FLT CREW AND THE CHIEF PLT TOOK PLACE. THE CHIEF PLT'S STATEMENT WAS THAT WE SHOULD HAVE ENTERED A HOLDING PATTERN AND TRIED TO DIAGNOSE THE PROB IN THE AIR. HE FURTHER CITED THE PROC FOR 'UNCOMMANDED ENG DECELERATION' IN THE CRJ-200 QRH. HOWEVER. WE EXPERIENCED FLUCTUATIONS CONSISTING OF BOTH ACCELERATIONS AND DECELERATIONS, WHICH CLRLY COULD NOT BE CLASSIFIED AS AN ENG DECELERATION. THERE IS NO EXISTING QRH PROC FOR THIS TYPE OF ABNORMALITY. ADDITIONALLY, I NEVER RECEIVED TRAINING THAT ADDRESSED THIS TYPE OF ISSUE. THEREFORE, DUE TO THE ABSENCE OF THIS TYPE OF TRAINING AND LEFT WITH NO CHKLIST TO FOLLOW THAT ADDRESSED THE PROB, THE CREW WAS FORCED TO USE GOOD JUDGEMENT AND EXECUTE A SAFE RETURN TO THE AIRFIELD.

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.