Cessna R172K N758DH accident near Big Bear City, California

Probable cause

The pilot's failure to attain and maintain an adequate airspeed that led to a stall/mush. Contributing to the accident was the lack of suitable terrain for an off airport landing and a high density altitude.

NTSB analysis

The pilot reported that after a longer-than-normal takeoff roll, the airplane lifted off the runway with a climb rate of about 300 to 400 feet per minute. As the airplane passed the end of the runway, climb performance suddenly decreased and the airplane started to descend. The pilot verified the throttle and propeller control positions, advanced the mixture to full rich, and applied 20 degrees of flaps as the airplane continued to descend. The pilot stated that due to trees and residential structures within the immediate area, he decided to initiate a controlled landing in a lake as close to the shoreline as possible. Subsequently, the pilot landed the airplane tail first in the water, resulting in substantial damage to both wings. The pilot did not report any mechanical anomalies with the engine or airframe. He added that at the time of the accident, the airplane was about 190 pounds under the maximum gross weight. The density altitude was calculated to be 9,100 feet mean sea level and the pressure altitude was claculated as 6,328 feet msl. Using the calculated pressure altitude, density altitude, aircraft's maximum gross weight, and reported weather conditions, a representative from the airframe manufacturer calculated that the airplane should have attained a climb rate of approximately 500 feet per minute at the time of the accident.

Text from the NTSB. Open the NTSB docket for LAX08LA187 for the full record.