North American/Aero Classics P 51D N1451D accident near Durango, Colorado

Probable cause

The pilot's failure to compensate for the high-performance airplane's tendency to enter a torque roll during the initial climb, which resulted in the airplane entering a torque roll and the subsequent loss of control at too low of an altitude to recover. Contributing to the pilot's failure to compensate for the airplane's tendency to enter a torque roll was his impairment from tetrahydrocannabinol.

NTSB analysis

The pilot was seated in the front seat and the flight instructor in the rear seat during an instructional flight. The pilot had not received an endorsement to fly solo in the airplane. Witnesses reported that, shortly after departure, the airplane entered a hard left bank to about 90 degrees, pitched up slightly, and then banked past 90 degrees to an inverted position. The airplane's nose then pitched down to about a 45-degree angle and then impacted terrain. The witness's description of the flight is consistent with a torque roll, which can occur after takeoff in airplanes that have a high-performance engine such as that installed in the accident airplane, and subsequent loss of control. Witnesses also indicated that the pilot typically dipped the left wing during takeoff to wave, and it is possible that the pilot did this during the accident flight and that this contributed to the torque roll. Due to the low altitude at the time of the torque roll, the flight instructor would not have had sufficient time to enter control inputs to regain control of the airplane before it impacted terrain.

Toxicology testing for the pilot detected tetrahydrocannabinol (THC), the active compound in marijuana, and its inactive metabolite in his cavity blood and lung tissue. It was determined there was enough THC in the pilot's system to have been impairing, and it is likely that this led to his failure to appropriately compensate for the risk of a torque roll in the high-performance airplane.

Text from the NTSB. Open the NTSB docket for CEN14FA339 for the full record.