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NTSB Report
September 16, 1988 · Hughes 369HS · N9110F
Columbia, CA
Overview
Report Status
Preliminary report
Event Type
Accident
Date
September 16, 1988
Injury Outcomes
No injuries (1 uninjured)
Location
Columbia, CA
Aircraft
Hughes 369HS
Tail Number
N9110F
Operator
Inter Mountain Helicopters
Injuries
None
Aircraft Damage
Substantial
NTSB Number
LAX88LA322
DURING AN EXTERNAL LOAD OPERATION, THERE WAS AN INDICATION OF HIGH TORQUE AND THE OIL CHIP LIGHT ILLUMINATED. THE ENGINE LOST POWER AND THE PILOT INITIATED AN AUTOROTATION. THE HELICOPTER COLLIDED WITH THE SLOPING TERRAIN AND ROLLED OVER. INSPECTION OF THE ENGINE REVEALED THAT THE NUMBER SIX AND SEVEN OIL SCREENS WERE IMPROPERLY INSTALLED RESTRICTING THE FLOW OF OIL. THE ENTIRE ENGINE EXHIBITED SIGNS OF LACK OF LUBRICATION AND EXCESSIVE TEMPERATURES.
Full Narrative
DURING AN EXTERNAL LOAD OPERATION, THERE WAS AN INDICATION OF HIGH TORQUE AND THE OIL CHIP LIGHT ILLUMINATED. THE ENGINE LOST POWER AND THE PILOT INITIATED AN AUTOROTATION. THE HELICOPTER COLLIDED WITH THE SLOPING TERRAIN AND ROLLED OVER. INSPECTION OF THE ENGINE REVEALED THAT THE NUMBER SIX AND SEVEN OIL SCREENS WERE IMPROPERLY INSTALLED RESTRICTING THE FLOW OF OIL. THE ENTIRE ENGINE EXHIBITED SIGNS OF LACK OF LUBRICATION AND EXCESSIVE TEMPERATURES.
Flight
Event TypeAccident
Event Time10:45 PDT
Nearest Airport0nm N
Runway0
Flight Plan FiledCvfr
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftHughes 369HS
Tail NumberN9110F
Aircraft CategoryHeli
DamageSubstantial
OperatorInter Mountain Helicopters
Operating RulePart 91
Engines1
Engine TypeTurboshaft
Engine DetailsAllison · 250-C20 · Turboshaft · 278
Seats4
People & Injuries
Injury SummaryNo injuries (1 uninjured)
Fatal0
Serious0
Minor0
Uninjured1
Total1
Crew 1Age 32 · Second Class
Conditions
ConditionsVMC
LightDaylight
Wind180° @ 5 kt
Visibility25 sm
CeilingNone
Temperature / Dew Point0 C
Altimeter0
Weather SourcePILO