On October 19, 1989, a Boeing A75N1 (registration N75863) was involved in an aviation accident near Salmon, ID. Investigators recorded the probable cause as: The pilot's failure to maintain adequate terrain clearance while maneuvering in mountainous terrain after encountering a downdraft. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
A pilot lost altitude while flying through a mountainous canyon due to a downdraft and crashed into a tree while attempting to turn around. No mechanical issues were reported.
What happened
The aircraft was operating on a cross-country flight path when it entered a canyon situated within mountainous terrain. During this phase of the flight, the airplane encountered a significant downdraft. This atmospheric condition caused the aircraft to begin losing altitude rapidly.
Recognizing the loss of height and the challenging environment, the pilot decided to execute a turn to reverse direction. However, during the execution of this maneuver, the airplane collided with a tree. The pilot later reported that there were no mechanical failures or malfunctions with the airplane at the time of the accident.
Probable cause
The pilot's failure to maintain adequate terrain clearance while maneuvering in mountainous terrain after encountering a downdraft.