Narrative:

This was an IFR flight; takeoff and climb was normal and the original altitude request of 4;000 ft was amended to 6;000 ft by the pilot in order to get on top of the cloud layer at 4;000 ft. No visible ice was observed during the climb out.upon reaching 6;000 ft MSL; oil started to flow freely onto the wind screen. Under the control of TRACON an emergency was declared and assistance requested. TRACON responded by providing a new transponder code and vectors to the nearest airport. As oil pressure was decreasing rapidly; power was reduced and an emergency descent started. Because oil covered the windscreen; visibility was greatly reduced and the descent was made on instruments. TRACON continued to provide vectors to the airport until radar and voice contact was lost at about 2;300 ft MSL. Airport was identified and landing was made. Upon inspection of the aircraft; it was determined that the crankcase breather tube was blocked by ice. This caused the crankcase to be pressurized and oil was forced out through the crankcase/prop seal. The aircraft lost 5 quarts of its 8 quart capacity. Contributing factors could have been that the aircraft was placed on heat 48 hours prior to take off; creating an excessive amount of moisture within engine crankcase and within engine compartment. Ambient air temperature was below 0 degrees F. Air intake winterization kit was not installed. Engine was not generating enough heat to dissipate moisture. Moisture picked up from climb through clouds.

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Original NASA ASRS Text

Title: PA-28 pilot experiences loss of engine oil and pressure; an emergency is declared followed by an uneventful landing.

Narrative: This was an IFR flight; takeoff and climb was normal and the original altitude request of 4;000 FT was amended to 6;000 FT by the pilot in order to get on top of the cloud layer at 4;000 FT. No visible ice was observed during the climb out.Upon reaching 6;000 FT MSL; oil started to flow freely onto the wind screen. Under the control of TRACON an emergency was declared and assistance requested. TRACON responded by providing a new transponder code and vectors to the nearest airport. As oil pressure was decreasing rapidly; power was reduced and an emergency descent started. Because oil covered the windscreen; visibility was greatly reduced and the descent was made on instruments. TRACON continued to provide vectors to the airport until radar and voice contact was lost at about 2;300 FT MSL. Airport was identified and landing was made. Upon inspection of the aircraft; it was determined that the crankcase breather tube was blocked by ice. This caused the crankcase to be pressurized and oil was forced out through the crankcase/prop seal. The aircraft lost 5 quarts of its 8 quart capacity. Contributing factors could have been that the aircraft was placed on heat 48 hours prior to take off; creating an excessive amount of moisture within engine crankcase and within engine compartment. Ambient air temperature was below 0 degrees F. Air intake winterization kit was not installed. Engine was not generating enough heat to dissipate moisture. Moisture picked up from climb through clouds.

Data retrieved from NASA's ASRS site as of July 2013 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.