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NTSB Report
May 26, 1991 · Bell 47-D1 · N339MC
Sun, LA
Overview
Report Status
Probable Cause
Event Type
Accident
Date
May 26, 1991
Injury Outcomes
No injuries (3 uninjured)
Location
Sun, LA
Aircraft
Bell 47-D1
Tail Number
N339MC
Operator
Cook Aviation
Injuries
None
Aircraft Damage
Substantial
NTSB Number
FTW91DRD05
THE PILOT HAD JUST DEPARTED A LOCAL FAIR GROUNDS WITH TWO PAYING PASSENGERS ON BOARD. AT APPROXIMATELY 300 FEET, A TOTAL LOSS OF ENGINE POWER WAS EXPERIENCED. THE PILOT INITIATED A 180 DEGREE AUTOROTATION IN ORDER TO CLEAR THE POPULATED AREA. THE AVAILABLE TERRAIN FOR LANDING WAS NOT LEVEL. DURING THE TOUCHDOWN, ROTOR RPM DECREASED DUE TO THE DIFFICULTY OF CONDUCTING A SLOPE LANDING. THE MAIN ROTOR BLADES SEVERED THE TAILBOOM OF THE HELICOPTER
NTSB Probable Cause
THE TOTAL LOSS OF POWER FOR UNDETERMINED REASONS AND THE FAILURE OF THE PILOT TO MAINTAIN ROTOR RPM. A FACTOR WAS THE LACK OF SUITABLE TERRAIN.
Full Narrative
THE PILOT HAD JUST DEPARTED A LOCAL FAIR GROUNDS WITH TWO PAYING PASSENGERS ON BOARD. AT APPROXIMATELY 300 FEET, A TOTAL LOSS OF ENGINE POWER WAS EXPERIENCED. THE PILOT INITIATED A 180 DEGREE AUTOROTATION IN ORDER TO CLEAR THE POPULATED AREA. THE AVAILABLE TERRAIN FOR LANDING WAS NOT LEVEL. DURING THE TOUCHDOWN, ROTOR RPM DECREASED DUE TO THE DIFFICULTY OF CONDUCTING A SLOPE LANDING. THE MAIN ROTOR BLADES SEVERED THE TAILBOOM OF THE HELICOPTER
Flight
Event TypeAccident
Event Time17:00 CDT
Nearest Airport0nm N
Runway0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftBell 47-D1
Tail NumberN339MC
Aircraft CategoryHeli
DamageSubstantial
OperatorCook Aviation
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsFranklin · 6V335A · Reciprocating · 210
Seats3
People & Injuries
Injury SummaryNo injuries (3 uninjured)
Fatal0
Serious0
Minor0
Uninjured3
Total3
Crew 1Age 40 · Second Class
Conditions
ConditionsVMC
LightDaylight
WindCalm
Visibility10 sm
CeilingBroken clouds 2500 ft
Temperature / Dew Point0 C
Altimeter0
Weather SourcePILO