What happened
The aircraft was engaged in a power line patrol mission when it collided with the ground. A rear seat occupant was aboard, serving as an observer and assisting the company with route familiarization for the pilot; however, this individual was not assigned any official crewmember duties. The accident occurred while the aircrew were patrolling the line toward the southwest against a headwind.
The aircraft impacted the ground in a steep nose-down attitude on the leeward side of steeply rising terrain. The wreckage was largely confined within a radius of 30 feet, with the exception of a fuel cap and a red navigation light that were found slightly farther away.
The investigation
Examination of the site revealed that the elevation of the crash location was approximately 7,000 feet MSL. Conditions at the time resulted in a density altitude of about 10,000 feet. Investigators found no preimpact failures and established that flight control continuity was maintained prior to impact.
Findings
The high density altitude likely contributed to reduced aircraft performance during the low-altitude patrol operation. The steep terrain and headwind conditions presented significant challenges for the aircrew navigating the power line corridor.