Narrative:

On a flight from mli to mdw the cockpit started to fill up with a little smoke. I asked approach control where and how far was the nearest airport. About 2 min later the oil pressure dropped out of the green. The oil temperature and cylinder temperature remained about the same. I reduced power, opened cowl flaps and enriched the mixture and declared an emergency. A min later the oil pressure dropped close to red line. At that point, I pulled power back to idle and flew a heading that approach gave me to joliet airport. At that point I was 2-3 mi away. I saw the airport and unknowingly lost 200' at which time approach gave me a current altimeter setting and asked me if I had the airport and asked if I wanted the visual approach. I told him yes. He cleared me for the approach and told me to cancel on the ground. I circled over the top of the airport and went on unicom and advised traffic of the emergency. The engine started to run very rough at which time I checked again that the power was all the way to idle which it was. I deployed the flaps when I was high and knew that landing was assured. I lowered the gear over the airport at 4000' so I could get used to that sink rate. On final I added a little power to make sure I had power if needed. The engine did respond to power. They found out that the seal on the turbo leaked and was burning out the oil.

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Original NASA ASRS Text

Title: LOSS OF OIL PRESSURE ACCOMPANIED BY SOME SMOKE IN COCKPIT.

Narrative: ON A FLT FROM MLI TO MDW THE COCKPIT STARTED TO FILL UP WITH A LITTLE SMOKE. I ASKED APCH CTL WHERE AND HOW FAR WAS THE NEAREST ARPT. ABOUT 2 MIN LATER THE OIL PRESSURE DROPPED OUT OF THE GREEN. THE OIL TEMPERATURE AND CYLINDER TEMP REMAINED ABOUT THE SAME. I REDUCED POWER, OPENED COWL FLAPS AND ENRICHED THE MIXTURE AND DECLARED AN EMER. A MIN LATER THE OIL PRESSURE DROPPED CLOSE TO RED LINE. AT THAT POINT, I PULLED POWER BACK TO IDLE AND FLEW A HDG THAT APCH GAVE ME TO JOLIET ARPT. AT THAT POINT I WAS 2-3 MI AWAY. I SAW THE ARPT AND UNKNOWINGLY LOST 200' AT WHICH TIME APCH GAVE ME A CURRENT ALTIMETER SETTING AND ASKED ME IF I HAD THE ARPT AND ASKED IF I WANTED THE VISUAL APCH. I TOLD HIM YES. HE CLRED ME FOR THE APCH AND TOLD ME TO CANCEL ON THE GND. I CIRCLED OVER THE TOP OF THE ARPT AND WENT ON UNICOM AND ADVISED TFC OF THE EMER. THE ENGINE STARTED TO RUN VERY ROUGH AT WHICH TIME I CHECKED AGAIN THAT THE POWER WAS ALL THE WAY TO IDLE WHICH IT WAS. I DEPLOYED THE FLAPS WHEN I WAS HIGH AND KNEW THAT LNDG WAS ASSURED. I LOWERED THE GEAR OVER THE ARPT AT 4000' SO I COULD GET USED TO THAT SINK RATE. ON FINAL I ADDED A LITTLE POWER TO MAKE SURE I HAD POWER IF NEEDED. THE ENGINE DID RESPOND TO POWER. THEY FOUND OUT THAT THE SEAL ON THE TURBO LEAKED AND WAS BURNING OUT THE OIL.

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.