This November 2007 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 177. Location: Auburn, Calif. Injuries: 2 Fatal. Aircraft damage: Destroyed.
What reportedly happened: The pilot and passenger had been on a personal flight that had lasted about 1.8 hours, and were returning to the airport. The airplane entered the traffic pattern. As it was on the base leg, the airspeed slowed, and witnesses indicated that it appeared to be at a high angle of attack. The airplane stalled, rolled into a spin, and hit trees and terrain.
No evidence of any pre-impact mechanical anomalies was discovered. At the time of the accident, conditions were ripe for serious carburetor icing conditions at glide power, however whether or not the pilot encountered carburetor icing could not be determined with the available evidence. The pilot had limited experience operating at the airport, and in the accident airplane make and model.
Toxicological tests were positive for brompheniramine and diphenhydramine, which are sedating antihistamines with adverse effects on performance, and often used to treat allergy symptoms. Although the toxicological test result levels were different between the FAA laboratory and local testing, both results were consistent with recent ingestion of a medication containing brompheniramine, which most likely impaired the pilot’s judgment and performance of complex cognitive and motor tasks during the flight.
Probable cause: The pilot failed to maintain an adequate airspeed while maneuvering in the traffic pattern for landing, which resulted in a stall/spin. The pilot’s impairment from the effects of over-the-counter medications was a factor.
For more information: NTSB.gov