Narrative:

[I was] conducting post-maintenance test flight with mechanic on board. After approximately 30 minutes of normal operation the engine experienced partial loss of power. Pilot set up landing. Engine failed completely on approach and the aircraft landed short of [the] runway. Aircraft was not damaged but engine would not restart immediately after landing. Engine did restart after about half an hour and the aircraft taxied to hangar under its own power. Mechanic is still attempting to determine the cause of the engine failure.

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Original NASA ASRS Text

Title: A C172 pilot reported loss of power during a post-maintenance test flight. He landed short of runway but no damage resulted.

Narrative: [I was] conducting post-maintenance test flight with mechanic on board. After approximately 30 minutes of normal operation the engine experienced partial loss of power. Pilot set up landing. Engine failed completely on approach and the aircraft landed short of [the] runway. Aircraft was not damaged but engine would not restart immediately after landing. Engine did restart after about half an hour and the aircraft taxied to hangar under its own power. Mechanic is still attempting to determine the cause of the engine failure.

Data retrieved from NASA's ASRS site as of April 2012 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.