On August 1, 2000, a Grumman G-164B (registration N6737K) was involved in an aviation accident near Tracy, CA. Investigators recorded the probable cause as: The pilot's abrupt course change and failure to maintain clearance from a transmission line. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
An agricultural airplane struck a 300-foot transmission line after an abrupt course change, severing its right wing and crashing. Marijuana metabolites were found in the pilot's system.
Accident Overview
During an agricultural application flight, the pilot executed an abrupt course change while repositioning the aircraft. This maneuver brought the airplane into proximity with a 300-foot-tall transmission line. The pilot failed to maintain adequate clearance, and the aircraft collided with the power line.
Impact and Post-Crash Fire
The collision severed a portion of the airplane's right wing. The aircraft then descended uncontrollably. Seconds after impacting the ground, the airplane caught fire.
Toxicology Findings
Toxicological analysis detected tetrahydrocannabinol carboxylic acid (a metabolite of marijuana) in the pilot's blood at a concentration of 0.018 ug/ml. The substance was also present in the pilot's urine.
Probable cause
The pilot's abrupt course change and failure to maintain clearance from a transmission line.