On March 29, 1992, a Beech B95 (registration N9652R) operated by Hmdr Enterprises was involved in an aviation accident near Devore, CA. Investigators recorded the probable cause as: The pilot's failure to remain clear of terrain while operating in marginal weather conditions at night, with a contributing factor being the presence of marijuana in his system. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
A pilot flying in a mountain pass area encountered low ceilings and dark conditions, reversing course before striking terrain.
What happened
The aircraft was operating in a mountainous region while approaching its destination airport. The pilot encountered low ceiling heights and marginal visual flight rules weather conditions during the approach phase. It was nighttime with limited visibility.
Unable to reach the intended destination due to these conditions, the pilot reversed course. While flying northbound, the airplane collided with the side of a mountain.
The investigation
A toxicological examination was conducted on the pilot following the accident. The results revealed the presence of tetrahydrocannabinol carboxylic acid (marihuana) in the pilot's blood at a level of 0.003 ug/ml.
Findings
The accident occurred during flight in mountainous terrain under nighttime conditions with marginal weather. The pilot was unable to maintain visual reference due to low ceilings and darkness, leading to controlled flight into terrain after reversing course. Substance use was identified as a contributing factor.
Probable cause
The pilot's failure to remain clear of terrain while operating in marginal weather conditions at night, with a contributing factor being the presence of marijuana in his system.