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.

the pilot's decision to fly an unairworthy and uncertificated airplane, his failure to perform an adequate preflight, and the improper installation of the oil cooler lines.