Cessna 170B N2865C accident near Auburn, California

Probable cause

The pilot's failure to maintain airplane control during approach to landing, which resulted in an inadvertent stall and subsequent spin.

NTSB analysis

The pilot's friend reported that he observed the accident airplane enter the airport traffic pattern but that he then diverted his attention to putting his airplane inside a hangar. Shortly after, when the accident airplane had not arrived, he immediately notified local authorities. The airplane wreckage was located the following morning in a heavily wooded area almost directly in line with the runway. Postaccident examination of the airframe, flight control system, and engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation.

GPS data revealed that the accident airplane entered the downwind leg of the airport traffic pattern and proceeded to turn left onto the base leg and final approach to the runway. The last three GPS data points showed the airplane at a groundspeed of about 64 knots, which was well above the stall speed. The GPS data showed that the airplane was well above the 3-degree glidepath to both the runway threshold and the precision approach path indicator location. Wreckage and impact signatures were consistent with a stall and subsequent spin and a near-vertical impact with terrain. However, the reason for the stall could not be determined.

Text from the NTSB. Open the NTSB docket for WPR13FA236 for the full record.