Narrative:

We performed a precautionary engine shutdown on #2 engine because of erratic fluctuations in the tgt gauge. Based on all available information and consideration of available alternatives, we decided this was the most prudent course of action. The crew who had the plane for the morning shift experienced viewing the tgt gauge for #2 engine drop to zero. They decided to feather that engine and write up the problem. When we reported for duty, the mechanics explained they could only find a fouled cannon plug. They cleaned it, ground tested the engine and signed off the maintenance release. By the time we received the paperwork and aircraft log from maintenance, the passenger were boarded and the load manifest completed. On taxi, the gauge fluctuated initially and then stabilized at a normal reading. We did a run up in the 13000-14000 RPM range and the gauge held steady. Based on this, we decided to take off. After takeoff, the gauge again started fluctuating, nominally at first. We continued with the departure, monitoring the gauge and other engine instruments. We were well aware that the checklist differentiates between 'repeated fluctuations of tgt' and 'sudden drop in tgt.' we decided to return to hnl and were given clearance after a couple of mi to turn back. The problem had been discussed with the flight attendant on taxi and after takeoff, and she made the initial announcement of the return to hnl. I also explained to the passenger why we were turning around when time permitted. We examined all facets of the gauge problem and decided the safest course would be to feather the engine, based on checklist procedure and examination of possible damage to the engine. We not only had 'repeated fluctuations' but also saw 'sudden drop' from 755 to zero degrees and back. We tried a power reduction with no result. We considered all the possible scenarios of why we needed the tgt gauge and when, even if all the other engine instruments were normal. We reached the decision that the safest and most conservative action was to feather the engine. We did not feel continuation of the flight would in any way be jeopardized by this action, whereas it would be possible to 'fry' the engine without a tgt gauge in the event of a go around. We followed the checklist for feathering the right engine and securing it. I gave a PA announcement and we landed uneventfully with the emergency equipment standing by.

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Original NASA ASRS Text

Title: FLC SHUT DOWN ENG DUE TO FLUCTUATIONS OF THE TGT GAUGE, DECLARED EMER AND RETURN LAND.

Narrative: WE PERFORMED A PRECAUTIONARY ENG SHUTDOWN ON #2 ENG BECAUSE OF ERRATIC FLUCTUATIONS IN THE TGT GAUGE. BASED ON ALL AVAILABLE INFO AND CONSIDERATION OF AVAILABLE ALTERNATIVES, WE DECIDED THIS WAS THE MOST PRUDENT COURSE OF ACTION. THE CREW WHO HAD THE PLANE FOR THE MORNING SHIFT EXPERIENCED VIEWING THE TGT GAUGE FOR #2 ENG DROP TO ZERO. THEY DECIDED TO FEATHER THAT ENG AND WRITE UP THE PROB. WHEN WE RPTED FOR DUTY, THE MECHS EXPLAINED THEY COULD ONLY FIND A FOULED CANNON PLUG. THEY CLEANED IT, GND TESTED THE ENG AND SIGNED OFF THE MAINT RELEASE. BY THE TIME WE RECEIVED THE PAPERWORK AND ACFT LOG FROM MAINT, THE PAX WERE BOARDED AND THE LOAD MANIFEST COMPLETED. ON TAXI, THE GAUGE FLUCTUATED INITIALLY AND THEN STABILIZED AT A NORMAL READING. WE DID A RUN UP IN THE 13000-14000 RPM RANGE AND THE GAUGE HELD STEADY. BASED ON THIS, WE DECIDED TO TAKE OFF. AFTER TKOF, THE GAUGE AGAIN STARTED FLUCTUATING, NOMINALLY AT FIRST. WE CONTINUED WITH THE DEP, MONITORING THE GAUGE AND OTHER ENG INSTS. WE WERE WELL AWARE THAT THE CHKLIST DIFFERENTIATES BTWN 'REPEATED FLUCTUATIONS OF TGT' AND 'SUDDEN DROP IN TGT.' WE DECIDED TO RETURN TO HNL AND WERE GIVEN CLRNC AFTER A COUPLE OF MI TO TURN BACK. THE PROB HAD BEEN DISCUSSED WITH THE FLT ATTENDANT ON TAXI AND AFTER TKOF, AND SHE MADE THE INITIAL ANNOUNCEMENT OF THE RETURN TO HNL. I ALSO EXPLAINED TO THE PAX WHY WE WERE TURNING AROUND WHEN TIME PERMITTED. WE EXAMINED ALL FACETS OF THE GAUGE PROB AND DECIDED THE SAFEST COURSE WOULD BE TO FEATHER THE ENG, BASED ON CHKLIST PROC AND EXAMINATION OF POSSIBLE DAMAGE TO THE ENG. WE NOT ONLY HAD 'REPEATED FLUCTUATIONS' BUT ALSO SAW 'SUDDEN DROP' FROM 755 TO ZERO DEGS AND BACK. WE TRIED A PWR REDUCTION WITH NO RESULT. WE CONSIDERED ALL THE POSSIBLE SCENARIOS OF WHY WE NEEDED THE TGT GAUGE AND WHEN, EVEN IF ALL THE OTHER ENG INSTS WERE NORMAL. WE REACHED THE DECISION THAT THE SAFEST AND MOST CONSERVATIVE ACTION WAS TO FEATHER THE ENG. WE DID NOT FEEL CONTINUATION OF THE FLT WOULD IN ANY WAY BE JEOPARDIZED BY THIS ACTION, WHEREAS IT WOULD BE POSSIBLE TO 'FRY' THE ENG WITHOUT A TGT GAUGE IN THE EVENT OF A GAR. WE FOLLOWED THE CHKLIST FOR FEATHERING THE R ENG AND SECURING IT. I GAVE A PA ANNOUNCEMENT AND WE LANDED UNEVENTFULLY WITH THE EMER EQUIP STANDING BY.

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.