What happened
The pilot was conducting a flight operation in an area characterized by significant topographical changes. The primary objective of this phase of the flight was to scout for potential landing sites suitable for future operations. While navigating through this environment, the pilot encountered a ridgeline and initiated a pass over it.
During this maneuver, the pilot realized that he had miscalculated the pitch of the rising terrain ahead. The aircraft was unable to climb at a rate sufficient to clear the increasing elevation of the hillside. Consequently, the airplane collided with the side of the hill. There were no reported mechanical issues with the aircraft prior to the accident.
The investigation
An examination of the flight data and pilot statements revealed that the aircraft was operating normally from a mechanical standpoint. The pilot explicitly stated that there were no preaccident mechanical problems with the airplane. The focus of the incident analysis shifted entirely to the pilot's situational awareness and navigation decisions relative to the terrain.
Findings
The primary factor in this accident was the pilot's failure to accurately assess the gradient of the rising terrain. By miscalculating the pitch, the pilot underestimated the climb performance required to safely clear the ridgeline. This error in judgment led directly to the collision with a hillside while the aircraft was attempting to maintain safe clearance over the obstacle.