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NTSB Report
December 4, 1992 · Hughes 369C · N9230F
Kamuela, HI
Overview
Report Status
Probable Cause
Event Type
Accident
Date
December 4, 1992
Injury Outcomes
2 injuries (2 minor injuries), 2 uninjured
Location
Kamuela, HI
Aircraft
Hughes 369C
Tail Number
N9230F
Operator
Mauna Kea Helicopters
Injuries
Minor
Aircraft Damage
Substantial
NTSB Number
LAX93LA062
WHILE ON A SIGHTSEEING FLIGHT, THE HELICOPTER SUSTAINED A TOTAL LOSS OF POWER. THE PILOT EXECUTED AN AUTOROTATION TO A NEARBY ROAD. ON TOUCH DOWN THE HELICOPTER YAWED TO THE LEFT AND SKIDDED OFF THE ROAD BUCKLING THE LEFT SKID. THE ENGINE EXAMINATION DISCLOSED THAT THE TURBINE WHEELS SUSTAINED EXTENSIVE HIGH TEMPERATURE DISTRESS. THE FUEL CONTROL EXCEEDED ITS SERVICE LIMITS ON THE START AND ACCELERATION SCHEDULES. THE FUEL FILTER VALVE WAS FOUND IN THE BYPASS POSITION WITH ITS SPRING RUSTED AND THE VALVE SEAT CONTAINED DIRT PARTICLES. THE TURBINE OUTLET TEMPERATURE INDICATOR GAVE FALSE INDICATIONS, A LOWER THAN APPLIED TEMPERATURE, THROUGHOUT ITS OPERATIONAL PARAMETERS WHICH EXCEEDED THE SERVICABLE TOLERANCES.
NTSB Probable Cause
THE INADEQUATE 100-HOUR INSPECTION PERFORMED BY COMPANY MAINTENANCE PERSONNEL. FACTORS CONTRIBUTING TO THIS ACCIDENT ARE THE FUEL CONTROL EXCEEDING THE MANUFACTURERS' SERVICE LIMITS; THE INOPERATIVE FUEL FILTER; THE OVERTEMPERATURE OF THE GAS GENERATOR TURBINE AND FREE TURBINE WHEELS; AND THE FALSE INDICATIONS OF THE TURBINE OUTLET TEMPERATURE INDICATOR.
Full Narrative
WHILE ON A SIGHTSEEING FLIGHT, THE HELICOPTER SUSTAINED A TOTAL LOSS OF POWER. THE PILOT EXECUTED AN AUTOROTATION TO A NEARBY ROAD. ON TOUCH DOWN THE HELICOPTER YAWED TO THE LEFT AND SKIDDED OFF THE ROAD BUCKLING THE LEFT SKID. THE ENGINE EXAMINATION DISCLOSED THAT THE TURBINE WHEELS SUSTAINED EXTENSIVE HIGH TEMPERATURE DISTRESS. THE FUEL CONTROL EXCEEDED ITS SERVICE LIMITS ON THE START AND ACCELERATION SCHEDULES. THE FUEL FILTER VALVE WAS FOUND IN THE BYPASS POSITION WITH ITS SPRING RUSTED AND THE VALVE SEAT CONTAINED DIRT PARTICLES. THE TURBINE OUTLET TEMPERATURE INDICATOR GAVE FALSE INDICATIONS, A LOWER THAN APPLIED TEMPERATURE, THROUGHOUT ITS OPERATIONAL PARAMETERS WHICH EXCEEDED THE SERVICABLE TOLERANCES.
Flight
Event TypeAccident
Event Time07:18 HST
Nearest Airport0nm
Runway0
Flight Plan FiledCvfr
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftHughes 369C
Tail NumberN9230F
Aircraft CategoryHeli
DamageSubstantial
OperatorMauna Kea Helicopters
Operating RulePart 135
Engines1
Engine TypeTurboshaft
Engine DetailsAllison · 250-C20 · Turboshaft · 400
Seats5
People & Injuries
Injury Summary2 injuries (2 minor injuries), 2 uninjured
Fatal0
Serious0
Minor2
Uninjured2
Total4
Crew 1Age 34 · Second Class
Conditions
ConditionsVMC
LightDaylight
Wind110° @ 5 kt
Visibility20 sm
CeilingNone
Temperature / Dew Point45 C / 41 C
Altimeter30.00 inHg
Observation Time17:18
Weather SourceWFAC