Narrative:

Unexplained loss of power approximately 1 1/2 mi east of runway 26, cno. Loss of power occurred at 1300' MSL, or 700' AGL. Pilot found it necessary to land in field southeast of runway. No injury to pilot. No passenger in plane. Damage to aircraft approximately $2000. Callback conversation with reporter revealed the following: reporter states the FAA and NTSB both inspected the aircraft and could find no specific cause. Possible problems are considered to be vapor lock, carburetor ice, fuel line interruption from turbulence. Definitely fuel line interruption from something. There was a great deal of moisture that day. It is not normal procedure to use carburetor heat in this aircraft on approach. Reporter feels the experience has certainly taught him to be ready for the unexpected.

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Original NASA ASRS Text

Title: ENGINE FAILURE ON APCH TO LNDG AT 700' AGL. LANDED 1 PT 5 MI FROM RWY IN A FIELD WITH LITTLE DAMAGE. NO INJURIES.

Narrative: UNEXPLAINED LOSS OF PWR APPROX 1 1/2 MI E OF RWY 26, CNO. LOSS OF PWR OCCURRED AT 1300' MSL, OR 700' AGL. PLT FOUND IT NECESSARY TO LAND IN FIELD SE OF RWY. NO INJURY TO PLT. NO PAX IN PLANE. DAMAGE TO ACFT APPROX $2000. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: RPTR STATES THE FAA AND NTSB BOTH INSPECTED THE ACFT AND COULD FIND NO SPECIFIC CAUSE. POSSIBLE PROBS ARE CONSIDERED TO BE VAPOR LOCK, CARB ICE, FUEL LINE INTERRUPTION FROM TURB. DEFINITELY FUEL LINE INTERRUPTION FROM SOMETHING. THERE WAS A GREAT DEAL OF MOISTURE THAT DAY. IT IS NOT NORMAL PROC TO USE CARB HEAT IN THIS ACFT ON APCH. RPTR FEELS THE EXPERIENCE HAS CERTAINLY TAUGHT HIM TO BE READY FOR THE UNEXPECTED.

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.