Incident Overview
During long-line operations, a helicopter experienced a sudden loss of engine power. The pilot executed a forced landing to a nearby road.
Post-Accident Findings
Examination of the helicopter after the accident revealed that it was not equipped with an engine air induction system deflector kit, commonly known as snow baffles. The FAA-approved Rotorcraft Flight Manual for the helicopter specifies in its Limitations Section: "The following equipment shall be installed when conducting flight operations in falling and/or blowing snow to reduce the possibility of engine flameout: The Particle Separator Engine Air Induction System Kit and the Deflector Kit."
Meteorological Conditions
Weather observation (METAR) at Stampede Pass, approximately 4 miles northeast of the accident site at an elevation of 3,800 feet MSL, reported winds from 090 degrees at 5 knots, visibility 1/4 statute mile, heavy snow and freezing fog, broken clouds at 300 feet, overcast at 1,400 feet, temperature dew point 18°F, and temperature 16°F.
Engine Inspection
A post-accident inspection of the engine found no evidence of a mechanical failure or malfunction.