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NTSB Report
July 24, 1987 · Bell 47G3 · N6355
Marston Mills, MA
Overview
Report Status
Preliminary report
Event Type
Accident
Date
July 24, 1987
Injury Outcomes
2 injuries (2 minor injuries), 1 uninjured
Location
Marston Mills, MA
Aircraft
Bell 47G3
Tail Number
N6355
Operator
Cornelius M Throwbridge Iii
Injuries
Minor
Aircraft Damage
Substantial
NTSB Number
NYC87LA210
THE HELICOPTER REACHED AN ALTITUDE OF ABOUT 50 FEET WHEN A LOSS OF POWER WAS EXPERIENCED. IMMEDIATELY THE PILOT SET UP FOR AN EMERGENCY LANDING AND SET THE HELICOPTER DOWN. THE AIRCRAFT, HOWEVER, COLLIDED WITH THE GROUND HARD AND INCURRED SUBSTANTIAL DAMAGE. CONDITIONS WERE CONDUCIVE TO CARBURETOR ICING DURING GLIDE POWER, NOT TKOF POWER. INVESTIGATION REVEALED THAT FUEL WAS IN THE FUEL TANKS. NO REASON WAS FOUND THAT COULD EXPLAIN THE LOSS OF POWER TO THE ENGINE.
Full Narrative
THE HELICOPTER REACHED AN ALTITUDE OF ABOUT 50 FEET WHEN A LOSS OF POWER WAS EXPERIENCED. IMMEDIATELY THE PILOT SET UP FOR AN EMERGENCY LANDING AND SET THE HELICOPTER DOWN. THE AIRCRAFT, HOWEVER, COLLIDED WITH THE GROUND HARD AND INCURRED SUBSTANTIAL DAMAGE. CONDITIONS WERE CONDUCIVE TO CARBURETOR ICING DURING GLIDE POWER, NOT TKOF POWER. INVESTIGATION REVEALED THAT FUEL WAS IN THE FUEL TANKS. NO REASON WAS FOUND THAT COULD EXPLAIN THE LOSS OF POWER TO THE ENGINE.
Flight
Event TypeAccident
Event Time15:40 EDT
Nearest AirportCAPECOD (0nm N)
Runway0
Runway Length0
Runway Width0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftBell 47G3
Tail NumberN6355
Aircraft CategoryHeli
DamageSubstantial
OperatorCornelius M Throwbridge Iii
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsFranklin · 6VS-335-A · Reciprocating · 225
Seats3
People & Injuries
Injury Summary2 injuries (2 minor injuries), 1 uninjured
Fatal0
Serious0
Minor2
Uninjured1
Total3
Crew 1Age 49 · First Class
Conditions
ConditionsVMC
LightDaylight
WindCalm
CeilingNone
Temperature / Dew Point0 C / 0 C
Altimeter0
Weather SourcePILO