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NTSB Report
November 1, 1985 · Hiller UH-12E · N400AH
Vernal, UT
Overview
Report Status
Preliminary report
Event Type
Accident
Date
November 1, 1985
Injury Outcomes
No injuries (2 uninjured)
Location
Vernal, UT
Aircraft
Hiller UH-12E
Tail Number
N400AH
Operator
Skybird Services
Injuries
None
Aircraft Damage
Substantial
NTSB Number
DEN86LA016
THE PLT STATED HE HAD JUST DEPARTED A SITE LOCATED ON TOP OF A MOUNTAIN, WHICH IS APPROXIMATELY 12,200 FT MSL. THE PILOT SAID 30 SECONDS LATER, THE HELICOPTER LOST PARTIAL POWER. REQUIRING HIM TO MAKE A FORCE LANDING. THE INSPECTION OF THE TURBOCHARGER REVEALED THE COMPRESSOR IMPELLER RETAINING NUT HAD BACKED OFF, ALLOWING THE COMPRESSOR IMPELLER TO CONTACT THE COMPRESSOR SHROUD AND LEADING TO THE SEIZURE OF THE IMPELLER. THIS RESULTED IN THE FAILURE OF THE TURBOCHARGER.
Full Narrative
THE PLT STATED HE HAD JUST DEPARTED A SITE LOCATED ON TOP OF A MOUNTAIN, WHICH IS APPROXIMATELY 12,200 FT MSL. THE PILOT SAID 30 SECONDS LATER, THE HELICOPTER LOST PARTIAL POWER. REQUIRING HIM TO MAKE A FORCE LANDING. THE INSPECTION OF THE TURBOCHARGER REVEALED THE COMPRESSOR IMPELLER RETAINING NUT HAD BACKED OFF, ALLOWING THE COMPRESSOR IMPELLER TO CONTACT THE COMPRESSOR SHROUD AND LEADING TO THE SEIZURE OF THE IMPELLER. THIS RESULTED IN THE FAILURE OF THE TURBOCHARGER.
Flight
Event TypeAccident
Event Time16:30 MST
Nearest AirportVERNAL (45nm WNW)
Runway0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftHiller UH-12E
Tail NumberN400AH
Aircraft CategoryHeli
DamageSubstantial
OperatorSkybird Services
Operating RulePart 135
Engines1
Engine TypeReciprocating
Engine DetailsLycoming · TIVO-540-A2A · Reciprocating · 315
Seats3
People & Injuries
Injury SummaryNo injuries (2 uninjured)
Fatal0
Serious0
Minor0
Uninjured2
Total2
Crew 1Age 32 · Second Class
Conditions
ConditionsVMC
LightDaylight
WindCalm
Visibility46 sm
CeilingNone
Temperature / Dew Point50 / 21 C
Altimeter30.00 inHg
Observation Time22:45
Weather SourceWFAC