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Aviation safety reports, made easier to study

NTSB Reports is an independent research and search tool for public aviation accident and incident records. It brings NTSB aviation reports, structured fields, docket files, extracted figures, photos, videos, and update history into one searchable interface.

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NTSB Report

August 7, 1990 · Aerospatiale SA315B · N351RM

Cougar, WA

Overview

Report Status
Probable Cause
Event Type
Accident
Date
August 7, 1990
Injury Outcomes
1 injury (1 serious injury)
Location
Cougar, WA
Aircraft
Aerospatiale SA315B
Tail Number
N351RM
Operator
Rocky Mountain Helicopters
Injuries
Serious
Aircraft Damage
Destroyed
NTSB Number
SEA90FA158

THE ACFT WAS HOVERING OVER TREES AT APPROX 200 FT. AGL, PICKING UP A LOAD OF LOGS DURING A LONG LINE HELI-LOGGING OPERATION, WHEN THE ENGINE LOST POWER. THE ACFT DESECENDED VERTICALLY AND IMPACTED THE TERRAIN. DISASSEMBLY AND EXAMINATION OF THE ENGINE SPEED GOVERNOR REVEALED PARTICLES OF SEALANT MATERIAL INSIDE THE GOVERNOR ASSY.

NTSB Probable Cause

LOSS OF POWER DUE TO CONTAMINATION IN THE ENGINE SPEED GOVERNOR.

Full Narrative

THE ACFT WAS HOVERING OVER TREES AT APPROX 200 FT. AGL, PICKING UP A LOAD OF LOGS DURING A LONG LINE HELI-LOGGING OPERATION, WHEN THE ENGINE LOST POWER. THE ACFT DESECENDED VERTICALLY AND IMPACTED THE TERRAIN. DISASSEMBLY AND EXAMINATION OF THE ENGINE SPEED GOVERNOR REVEALED PARTICLES OF SEALANT MATERIAL INSIDE THE GOVERNOR ASSY.

Flight

Event TypeAccident
Event Time11:30 PDT
Nearest Airport0nm N
Runway0
Runway Length0
Runway Width0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo

Aircraft

AircraftAerospatiale SA315B
Tail NumberN351RM
Aircraft CategoryHeli
DamageDestroyed
OperatorRocky Mountain Helicopters
Operating RulePart 133
Engines1
Engine TypeTurboshaft
Engine DetailsTurbomeca · ARTOUSTE IIIB · Turboshaft · 853
Seats5

People & Injuries

Injury Summary1 injury (1 serious injury)
Fatal0
Serious1
Minor0
Uninjured0
Total1
Crew 1Age 42 · Second Class

Conditions

ConditionsVMC
LightDaylight
Wind310° @ 5 kt
Visibility40 sm
CeilingNone
Temperature / Dew Point57
Altimeter30.00 inHg
Observation Time17:50
Weather SourceWFAC

Appendix: Source Data