Cessna 150 N7158X accident near Brawley, California

Probable cause

The pilot’s decision to perform a flight while impaired by the effects of alcohol and cocaine, and his failure to maintain terrain clearance during the flight.

NTSB analysis

The noninstrument-rated pilot departed after midnight in dark night conditions. After takeoff, the airplane maneuvered in the vicinity of the airport for 3 minutes before impacting trees on the bank of a river. A postaccident examination of the airframe and engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation.

The pilot did not hold a current Federal Aviation Administration medical certificate; his most recent medical certificate was issued 4 years before the accident (at which time he reported no previous flight experience). The pilot’s total and recent flight experience could not be confirmed.

Postmortem toxicological testing revealed ethanol in the pilot’s blood, vitreous, and urine. The testing also revealed cocaine, benzoylecgonine (cocaine metabolite), cocaethylene (a substance that forms when cocaine is metabolized in the presence of ethanol), and ecgonine methyl ester (cocaine metabolite) in the pilot’s blood and urine.

The levels of ethanol in the pilot’s postmortem blood, vitreous, and urine fit a pattern consistent with ethanol consumption. At the time of the pilot’s death, he had a blood ethanol level more than five times the regulatory limit for conducting a flight, which would be expected to produce marked impairment.

Unlike the high measured levels of ethanol, the measured levels of cocaine and its metabolites in the pilot’s blood were low. However, postmortem cocaine levels do not directly predict impairing effects, and the effects of cocaine (a central nervous system stimulant) and ethanol (a central nervous system depressant) are not additive. Accordingly, cocaine’s effects on the pilot at the time of the accident flight and how such effects may have interacted with those of ethanol, are unknown. However, the pilot’s decision to perform the flight on a dark night, after consuming alcohol and cocaine, and his failure to maintain terrain clearance are evidence of impaired judgment and performance consistent with known effects of ethanol and cocaine.

Text from the NTSB. Open the NTSB docket for WPR20FA018 for the full record.