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Aviation safety reports, made easier to study

NTSB Reports is an independent research and search tool for public aviation accident and incident records. It brings NTSB aviation reports, structured fields, docket files, extracted figures, photos, videos, and update history into one searchable interface.

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NTSB Report

April 26, 1990 · Bell 47G5 · N8591F

Marion, MA

Overview

Report Status
Probable Cause
Event Type
Accident
Date
April 26, 1990
Injury Outcomes
No injuries (1 uninjured)
Location
Marion, MA
Aircraft
Bell 47G5
Tail Number
N8591F
Operator
Plymouth Copters
Injuries
None
Aircraft Damage
Substantial
NTSB Number
NYC90DNA02

THE PILOT REPORTED THAT HE WAS PERFORMING AN 'AG TURN' DURING AERIAL APPLICATION OPERATIONS WHEN A LOSS OF ENGINE POWER WAS NOTED. THE HELICOPTER DESCENDED INTO TREES AND BRUSH. THE PILOT STATED THAT 'CARBURETOR ICE WAS SUSPECTED THROUGHOUT THE DAY. CARBURETOR HEAT WAS APPLIED INTERMITTENTLY DURING THE DAY.' ON- SCENE INVESTIGATION REVEALED NO INDICATION OF MECHANICAL DIFFICULTY/MALFUNCTION; THERE WAS FUEL ON BOARD THE HELICOPTER, AND NO EVIDENCE OF CONTAMINATION IN THE FUEL SYSTEM. A POST- ACCIDENT ENGINE RUN WAS ACCOMPLISHED WITH NO INDICATION OF POWER LOSS.

NTSB Probable Cause

IMPROPER USE OF CARBURETOR HEAT BY THE PILOT RESULTING IN A LOSS OF ENGINE POWER. THE LACK OF SUITABLE TERRAIN FOR A FORCED LANDING WAS A FACTOR.

Full Narrative

THE PILOT REPORTED THAT HE WAS PERFORMING AN 'AG TURN' DURING AERIAL APPLICATION OPERATIONS WHEN A LOSS OF ENGINE POWER WAS NOTED. THE HELICOPTER DESCENDED INTO TREES AND BRUSH. THE PILOT STATED THAT 'CARBURETOR ICE WAS SUSPECTED THROUGHOUT THE DAY. CARBURETOR HEAT WAS APPLIED INTERMITTENTLY DURING THE DAY.' ON- SCENE INVESTIGATION REVEALED NO INDICATION OF MECHANICAL DIFFICULTY/MALFUNCTION; THERE WAS FUEL ON BOARD THE HELICOPTER, AND NO EVIDENCE OF CONTAMINATION IN THE FUEL SYSTEM. A POST- ACCIDENT ENGINE RUN WAS ACCOMPLISHED WITH NO INDICATION OF POWER LOSS.

Flight

Event TypeAccident
Event Time17:30 EDT
Nearest Airport0nm N
Runway0
Runway Length0
Runway Width0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo

Aircraft

AircraftBell 47G5
Tail NumberN8591F
Aircraft CategoryHeli
DamageSubstantial
OperatorPlymouth Copters
Operating RulePart 137
Engines1
Engine TypeReciprocating
Engine DetailsLycoming · L-34-22-31 · Reciprocating · 260
Seats2

People & Injuries

Injury SummaryNo injuries (1 uninjured)
Fatal0
Serious0
Minor0
Uninjured1
Total1
Crew 1Age 24 · Second Class

Conditions

ConditionsVMC
LightDaylight
Wind190° @ 10 kt
Visibility11 sm
CeilingNone
Temperature / Dew Point52 / 46
Altimeter29.00 inHg
Weather SourceWFAC

External Links

Appendix: Source Data