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NTSB Report
September 7, 1984 · Aerospatiale SA315B · N62338
Lyman, WY
Overview
Report Status
Preliminary report
Event Type
Accident
Date
September 7, 1984
Injury Outcomes
5 injuries (5 minor injuries)
Location
Lyman, WY
Aircraft
Aerospatiale SA315B
Tail Number
N62338
Operator
Evergreen Helicopters
Injuries
Minor
Aircraft Damage
Substantial
NTSB Number
DEN84LA286
THE PLT STATED THAT ENGINE RPM BEGAN DETERIORATING DURING A CLIMB TO CRUISE FLT. HE RETURNED TO THE LANDING SITE WHERE THE RPM DECAYED TO FLT IDLE, AN AUTOROTATION WAS ENTERED AND A HARD LANDING RESULTED. THE ENGINE RAN FOR 1 HOUR IN A TEST CELL AFTER THE ACCIDENT AND NO EVIDENCE OF A MALFUNCTION WAS FOUND. THE FUEL SPEED GOVERNOR WAS REMOVED, TESTED AND FOUND TO FUNCTION NORMALLY HOWEVER DURING THE REMOVAL OF THE FUEL METERING SYSTEM PART OF AN 'O' RING WAS FOUND IN A SPRING NEXT TO THE FUEL PORTS. THE 'O' RING FRAGMENT COULD HAVE BLOCKED ONE OF THE FUEL PORTS ALLOWING THE RPM TO DROP TO FLIGHT IDLE.
Full Narrative
THE PLT STATED THAT ENGINE RPM BEGAN DETERIORATING DURING A CLIMB TO CRUISE FLT. HE RETURNED TO THE LANDING SITE WHERE THE RPM DECAYED TO FLT IDLE, AN AUTOROTATION WAS ENTERED AND A HARD LANDING RESULTED. THE ENGINE RAN FOR 1 HOUR IN A TEST CELL AFTER THE ACCIDENT AND NO EVIDENCE OF A MALFUNCTION WAS FOUND. THE FUEL SPEED GOVERNOR WAS REMOVED, TESTED AND FOUND TO FUNCTION NORMALLY HOWEVER DURING THE REMOVAL OF THE FUEL METERING SYSTEM PART OF AN 'O' RING WAS FOUND IN A SPRING NEXT TO THE FUEL PORTS. THE 'O' RING FRAGMENT COULD HAVE BLOCKED ONE OF THE FUEL PORTS ALLOWING THE RPM TO DROP TO FLIGHT IDLE.
Flight
Event TypeAccident
Event Time08:50 MDT
Nearest Airport0nm N
Runway0
Runway Length0
Runway Width0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftAerospatiale SA315B
Tail NumberN62338
Aircraft CategoryHeli
DamageSubstantial
OperatorEvergreen Helicopters
Operating RulePart 135
Engines1
Engine TypeTurboshaft
Engine DetailsTurbomeca · ARTOUSTE IIIB · Turboshaft · 562
Seats5
People & Injuries
Injury Summary5 injuries (5 minor injuries)
Fatal0
Serious0
Minor5
Uninjured0
Total5
Crew 1Age 35 · Second Class
Conditions
ConditionsVMC
LightDaylight
Wind90° @ 10 kt
Visibility10 sm
CeilingOvercast 2000 ft
Temperature / Dew Point46 / 34 C
Altimeter30.00 inHg
Observation Time09:47