Narrative:

Took off from ZZZ at XA00 local time with 2 passenger, 218 pounds of cargo and 4000 pounds of fuel on flight abc. After 30 mins of flight, when we had just reached our final proposed altitude of 17000 ft, we noticed a slight decrease in torque on the right engine. It slowly kept decreasing and after talking with our dispatch office and maintenance department, I decided to turn around back to ZZZ. All the other engine indicators where normal at this time, but after a few mins the oil pressure dropped and the red oil pressure light for the right engine illuminated on the annunciator panel. At this time we proceeded to perform a precautionary engine shut down and accomplish the emergency shut down engine in flight checklist. We declared an emergency and continued to the nearest suitable airport which was ZZZ and safely landed the aircraft. No further assistance was needed. Callback conversation with reporter revealed the following information: the reporter stated at level cruise the right torque indication started a slow decrease and continued this decrease with all other engine indications normal. The reporter said after deciding to divert and turning back the right engine oil pressure dropped and the red low pressure warning light illuminated. The reporter stated the engine was shutdown per the checklist and an emergency declared. The reporter said maintenance reported a failed high pressure turbine bearing was the cause and the engine was changed. The reporter stated the engine was a garrett tpe 331-11-612G.

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Original NASA ASRS Text

Title: A FAIRCHILD SA-227 AT 17000 FT DECLARED AND EMER AND DIVERTED DUE TO R ENGINE TORQUE DECREASE AND LOSS OF OIL PRESSURE.

Narrative: TOOK OFF FROM ZZZ AT XA00 LCL TIME WITH 2 PAX, 218 LBS OF CARGO AND 4000 LBS OF FUEL ON FLT ABC. AFTER 30 MINS OF FLT, WHEN WE HAD JUST REACHED OUR FINAL PROPOSED ALT OF 17000 FT, WE NOTICED A SLIGHT DECREASE IN TORQUE ON THE R ENGINE. IT SLOWLY KEPT DECREASING AND AFTER TALKING WITH OUR DISPATCH OFFICE AND MAINT DEPARTMENT, I DECIDED TO TURN AROUND BACK TO ZZZ. ALL THE OTHER ENGINE INDICATORS WHERE NORMAL AT THIS TIME, BUT AFTER A FEW MINS THE OIL PRESSURE DROPPED AND THE RED OIL PRESSURE LIGHT FOR THE R ENGINE ILLUMINATED ON THE ANNUNCIATOR PANEL. AT THIS TIME WE PROCEEDED TO PERFORM A PRECAUTIONARY ENGINE SHUT DOWN AND ACCOMPLISH THE EMER SHUT DOWN ENGINE IN FLT CHKLIST. WE DECLARED AN EMER AND CONTINUED TO THE NEAREST SUITABLE ARPT WHICH WAS ZZZ AND SAFELY LANDED THE ACFT. NO FURTHER ASSISTANCE WAS NEEDED. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED AT LEVEL CRUISE THE R TORQUE INDICATION STARTED A SLOW DECREASE AND CONTINUED THIS DECREASE WITH ALL OTHER ENGINE INDICATIONS NORMAL. THE RPTR SAID AFTER DECIDING TO DIVERT AND TURNING BACK THE R ENGINE OIL PRESSURE DROPPED AND THE RED LOW PRESSURE WARNING LIGHT ILLUMINATED. THE RPTR STATED THE ENGINE WAS SHUTDOWN PER THE CHKLIST AND AN EMER DECLARED. THE RPTR SAID MAINT RPTED A FAILED HIGH PRESSURE TURBINE BEARING WAS THE CAUSE AND THE ENGINE WAS CHANGED. THE RPTR STATED THE ENGINE WAS A GARRETT TPE 331-11-612G.

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.