Narrative:

Over windsor VOR, a passenger reported to our F/a that he saw fluid leaking out of the top of the right engine nacelle. The F/a made the report to the first officer and me. The first officer went back to the cabin to determine the validity of the report. He reported to me that oil was streaming from the engine and that it was possible that we had an oil leak. We descended into the cleveland area and were told by cleveland approach that we were #4 for landing, but there would be no delay. The first officer and I reviewed the precautionary engine shutdown procedures and single-engine landing procedures. Cleveland approach then gave us a vector for traffic away from the airport when we were still 20 mi away. I then informed approach that we had a possible oil leak and would like expeditious handling, if possible. Approach immediately turned us to the airport and cleared us for the visual. We did notice a slight decrease in oil pressure during the descent and landing, but the pressure always stayed in the green arc. Approach asked if we would like to have the rescue crews standing by, to which we answered affirmative. The landing was normal. After taxiing off the runway, we shut down the engine. We then taxied into the gate with no subsequent problems. Subsequent inspection found no oil loss in the engine. Quantity was the same as it had been prior to departure of the 45-minute flight. The only explanation the mechanics could offer was that excess oil was normally vented out from this vent and a larger amount than normal was vented out over a short period of time. The first officer has ridden in the cabin many times and said he was familiar with the oil vent, so I trusted his judgement call and proceeded on the basis that the engine could seize with only a few minutes' notice.

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Original NASA ASRS Text

Title: FLT CREW DECLARES EMERGENCY DUE APPARENT ENGINE OIL LEAK.

Narrative: OVER WINDSOR VOR, A PAX REPORTED TO OUR F/A THAT HE SAW FLUID LEAKING OUT OF THE TOP OF THE RIGHT ENGINE NACELLE. THE F/A MADE THE REPORT TO THE F/O AND ME. THE F/O WENT BACK TO THE CABIN TO DETERMINE THE VALIDITY OF THE REPORT. HE REPORTED TO ME THAT OIL WAS STREAMING FROM THE ENGINE AND THAT IT WAS POSSIBLE THAT WE HAD AN OIL LEAK. WE DESCENDED INTO THE CLEVELAND AREA AND WERE TOLD BY CLEVELAND APCH THAT WE WERE #4 FOR LNDG, BUT THERE WOULD BE NO DELAY. THE F/O AND I REVIEWED THE PRECAUTIONARY ENGINE SHUTDOWN PROCS AND SINGLE-ENGINE LNDG PROCS. CLEVELAND APCH THEN GAVE US A VECTOR FOR TFC AWAY FROM THE ARPT WHEN WE WERE STILL 20 MI AWAY. I THEN INFORMED APCH THAT WE HAD A POSSIBLE OIL LEAK AND WOULD LIKE EXPEDITIOUS HANDLING, IF POSSIBLE. APCH IMMEDIATELY TURNED US TO THE ARPT AND CLRED US FOR THE VISUAL. WE DID NOTICE A SLIGHT DECREASE IN OIL PRESSURE DURING THE DSCNT AND LNDG, BUT THE PRESSURE ALWAYS STAYED IN THE GREEN ARC. APCH ASKED IF WE WOULD LIKE TO HAVE THE RESCUE CREWS STANDING BY, TO WHICH WE ANSWERED AFFIRMATIVE. THE LNDG WAS NORMAL. AFTER TAXIING OFF THE RWY, WE SHUT DOWN THE ENGINE. WE THEN TAXIED INTO THE GATE WITH NO SUBSEQUENT PROBLEMS. SUBSEQUENT INSPECTION FOUND NO OIL LOSS IN THE ENGINE. QUANTITY WAS THE SAME AS IT HAD BEEN PRIOR TO DEP OF THE 45-MINUTE FLT. THE ONLY EXPLANATION THE MECHANICS COULD OFFER WAS THAT EXCESS OIL WAS NORMALLY VENTED OUT FROM THIS VENT AND A LARGER AMOUNT THAN NORMAL WAS VENTED OUT OVER A SHORT PERIOD OF TIME. THE F/O HAS RIDDEN IN THE CABIN MANY TIMES AND SAID HE WAS FAMILIAR WITH THE OIL VENT, SO I TRUSTED HIS JUDGEMENT CALL AND PROCEEDED ON THE BASIS THAT THE ENGINE COULD SEIZE WITH ONLY A FEW MINUTES' NOTICE.

Data retrieved from NASA's ASRS site as of August 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.