Narrative:

The flight departed at approximately XA20 from santa rosa. 10 mins after takeoff I registered a very light but strange smell in the cabin. At approximately XC00, over sjc, 13500 ft I saw oil coming from the engine compartment. I declared an emergency and landed at sjc. All engine instruments indicated normal at all times. The engine still had 5 quarts of oil. The oil cap had come loose during flight.

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Original NASA ASRS Text

Title: A CESSNA 210 IN CRUISE AT 13500 FT DECLARED AN EMER AND DIVERTED DUE TO OIL LEAKING FROM THE ENG COWLING CAUSED BY AN UNSECURED OIL FILLER CAP.

Narrative: THE FLT DEPARTED AT APPROX XA20 FROM SANTA ROSA. 10 MINS AFTER TKOF I REGISTERED A VERY LIGHT BUT STRANGE SMELL IN THE CABIN. AT APPROX XC00, OVER SJC, 13500 FT I SAW OIL COMING FROM THE ENG COMPARTMENT. I DECLARED AN EMER AND LANDED AT SJC. ALL ENG INSTS INDICATED NORMAL AT ALL TIMES. THE ENG STILL HAD 5 QUARTS OF OIL. THE OIL CAP HAD COME LOOSE DURING FLT.

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.