Accident Overview
An airplane conducting a cross-country flight from Colorado to California collided with mountainous terrain in a box canyon under clear skies. The aircraft came to rest on a snowy slope with an incline of approximately 25 degrees on the south side of the canyon, situated about 300 to 400 feet below the top of the ridgeline. The canyon was oriented east-west, with rising terrain to the west, north, and south.
Wreckage and Energy Path
The ground scars and wreckage debris distribution indicated an energy path trending eastward, contrary to the expected flight direction and toward lower terrain. This suggests the airplane was moving eastward at the time of impact.
Weather Conditions
A study of weather data and satellite imagery confirmed that the skies were clear with unrestricted visibility. Considering the mountainous terrain and winds aloft, light to moderate turbulence below 15,000 feet was possible. The density altitude at the accident site was calculated to be just over 6,000 feet.
Survivability and Toxicology
The pilot survived the accident but later succumbed to his injuries and environmental exposure. It was not possible to determine exactly how long the pilot survived after the accident, and therefore it could not be determined whether the pilot last used marijuana before or after the accident. A plastic bag of marijuana was found on the pilot, and two bags of marijuana were on the passenger. Toxicology reports for both individuals were positive for tetrahydrocannabinol (the active substance in marijuana) and tetrahydrocannabinol carboxylic acid (an inactive metabolite).
Mechanical Examination
A post-accident examination revealed no evidence of pre-impact mechanical malfunction or failure of the engine and airframe.
Conclusion
No probable cause was determined from the investigation.