Amateur-built Qualt N3215S accident near Sonoma, California

Probable cause

A partial loss of engine power for reasons that could not be determined because postaccident examination of the airframe and engine did not reveal any anomalies that would have precluded normal operation.

NTSB analysis

The pilot reported that after takeoff it felt as if the airplane was in a strong downdraft or strong tailwind gust and that "somehow there was not enough power.” When the airplane reached about 100 to 150 feet above ground level, it veered right, rapidly descended, and collided with a warehouse. A witness reported that he heard the engine running but that it was only producing partial power. During the postaccident examination of the engine, the engine started without hesitation and ran smoothly during a test run. Although the reported weather conditions were conducive to serious carburetor icing at cruise power, it could not be determined if carburetor icing was the reason for the partial loss of engine power. Further, weather conditions were not conducive to strong wind.

Text from the NTSB. Open the NTSB docket for WPR11LA039 for the full record.