Primary finding
Probable cause
The pilot’s inability to maintain directional control following a collision with a boulder during an off airport precautionary landing.
Investigator assessment
Analysis narrative
The pilot in the tailwheel-equipped airplane reported that he made a precautionary landing after observing slightly elevated engine exhaust gas temperatures. The pilot selected an off-airport grass covered surface and touched down. During the landing roll, the left main landing gear struck a boulder that was obscured by the grass, which resulted in the landing gear cabane V to break, and the left wing struck the ground. The pilot stated that he had no rudder authority or braking, and the airplane continued to slowly move left into a creek and nosed over. The airplane sustained substantial damage to the left wing lift strut and rudder. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation.