Incident Overview
A helicopter on a sight-seeing passenger flight in the Mount St. Helens area was reported overdue, prompting a search. The wreckage was later discovered in a heavily wooded area on relatively level terrain near the North Fork of the Toutle River, at an elevation of approximately 800 feet. No known witnesses were present at the time of the crash.
Crash Site Examination
Inspection of the crash site revealed that only trees within 34 feet of the wreckage sustained damage. The helicopter was found to have burned extensively, with fire damage particularly severe in the cockpit area. Despite the fire, the instrument panel yielded partial readings: the N1 rpm gauge indicated 72%, the N2 rpm gauge showed 43%, and the rotor rpm gauge registered 35%.
Rotor and Engine Condition
Examination of the main and tail rotor blades revealed a lack of rotational damage, suggesting low or no blade rotation at impact. The engine showed some rotational damage, but no preimpact mechanical failure or malfunction was verified. The fuel control unit, fuel governor, and fuel pump were destroyed by fire, precluding further analysis.
Investigation Findings
The investigation did not identify any preexisting mechanical issues or malfunctions that could explain the crash. The cause of the accident remains undetermined based on the available evidence.