This December 2009 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.
Aircraft: Cessna 172. Injuries: None. Location: Albion, Idaho. Aircraft damage: Substantial.
What reportedly happened: The pilot reported that he was conducting an aerial observation flight during night visual meteorological conditions. As the airplane approached the ridge tops of a mountain range at an altitude of about 800 to 1,000 feet above ground level, the airplane rolled uncommanded into a 90° left bank.
The pilot corrected the roll and regained his original heading. Shortly after, the airplane encountered “another gust” and rolled to the right. As he was rolling back to level flight he realized that the top of the hill was higher than his altitude and remained in a right turn. During the turn, the pilot saw the ground illuminated by the landing light and then the airplane hit the ground.
Probable cause: The pilot’s failure to maintain clearance from mountainous terrain while maneuvering in gusting winds.
For more information: NTSB.gov; NTSB Identification: WPR10CA089