Piper PA 24-260 N9032P accident near Spring Branch, Texas

Probable cause

The pilot's failure to maintain control during takeoff due to his impairment from marijuana. Contributing to the accident was the pilot’s impaired decision to fly after using a disqualifying drug.

NTSB analysis

The private pilot was departing on a local flight with three passengers in the complex, high-performance airplane. Shortly after takeoff, the airplane descended and impacted terrain near a store parking lot. Postaccident examination of the airplane did not reveal any anomalies that would have precluded normal operation. Toxicological testing of the pilot revealed the presence of marijuana and its metabolite (THC and THC-COOH). THC is a psychoactive drug with potential effects such as decreased ability to concentrate and maintain attention, and impaired hand-eye coordination; these effects can present with blood levels of THC as low as 1 ng/ml. Due to postmortem redistribution, the exact level of THC and THC-COOH at the time of the accident could not be determined; however, the pilot's minimum THC level was likely about 5-11 ng/ml, and his THC-COOH level was likely about 3-4 ng/ml. His actual levels could have been higher at the time of the accident, and would likely have been higher during the time of preflight decision-making. The accident was consistent with a loss of control after takeoff due to the pilot's impairment by the effects of marijuana.

Text from the NTSB. Open the NTSB docket for CEN15FA232 for the full record.