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NTSB Report
July 26, 1984 · Aerospatiale 316B · N4246
Naturita, CO
Overview
Report Status
Preliminary report
Event Type
Accident
Date
July 26, 1984
Injury Outcomes
No injuries (1 uninjured)
Location
Naturita, CO
Aircraft
Aerospatiale 316B
Tail Number
N4246
Operator
Alpine Helicopter Services
Injuries
None
Aircraft Damage
Substantial
NTSB Number
DEN84LA239
ONE OF THE AXIAL COMPRESSOR BLADES SEPARATED RESULTING IN INTERNAL ENGINE DAMAGE AND LOSS OF ENGINE POWER. EXAMINATION OF THE BLADES SHOWED EVIDENCE OF CORROSION BEYOND ACCEPTABLE LIMITS. THE ENGINE WAS NOT EQUIPPED WITH AN AIR FILTER OR PARTICLE SEPARATOR. HELICOPTER DAMAGE WAS SUSTAINED DURING GROUND CONTACT.
Full Narrative
ONE OF THE AXIAL COMPRESSOR BLADES SEPARATED RESULTING IN INTERNAL ENGINE DAMAGE AND LOSS OF ENGINE POWER. EXAMINATION OF THE BLADES SHOWED EVIDENCE OF CORROSION BEYOND ACCEPTABLE LIMITS. THE ENGINE WAS NOT EQUIPPED WITH AN AIR FILTER OR PARTICLE SEPARATOR. HELICOPTER DAMAGE WAS SUSTAINED DURING GROUND CONTACT.
Flight
Event TypeAccident
Event Time07:45 MDT
Nearest Airport0nm
Runway0
Runway Length0
Runway Width0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftAerospatiale 316B
Tail NumberN4246
Aircraft CategoryHeli
DamageSubstantial
OperatorAlpine Helicopter Services
Operating RulePart 133
Engines1
Engine TypeTurboshaft
Engine DetailsTurbomeca · ARTOUSTE IIB · Turboshaft · 562
Seats7
People & Injuries
Injury SummaryNo injuries (1 uninjured)
Fatal0
Serious0
Minor0
Uninjured1
Total1
Crew 1Age 38 · Second Class
Conditions
ConditionsVMC
LightDaylight
WindCalm
Visibility60 sm
CeilingNone
Temperature / Dew Point70 F / 0 C
Altimeter0
Weather SourcePILO