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NTSB Report
August 23, 1989 · Bell 47G · N955B
Ponce, PR
Overview
Report Status
Probable Cause
Event Type
Accident
Date
August 23, 1989
Injury Outcomes
No injuries (1 uninjured)
Location
Ponce, PR
Aircraft
Bell 47G
Tail Number
N955B
Operator
Esteves Arturo
Injuries
None
Aircraft Damage
Substantial
NTSB Number
MIA89LA229
THE STUDENT PLT WAS ON AN APCH TO LAND ON A X-COUNTRY FLT, WHEN THE AFT TAIL ROTOR DRIVE SHAFT (PN: 47-644-187) FAILED AT ABOUT 40' AGL. HE RPRTD THE HELICOPTER BEGAN TO SPIN TO THE RIGHT, SO HE CLOSED THE THROTTLE & THE SPINNING STOPPED. HE PULLED UP ON THE COLLECTIVE TO CUSHION THE LANDING, BUT RAN OUT OF COLLECTIVE PITCH AT ABOUT 10' ABOVE THE GROUND. SUBSEQUENTLY, THE HELICOPTER TOUCHED DOWN HARD, DAMAGING THE TAIL ROTOR & TAIL BOOM. THE TAIL ROTOR DRIVE SHAFT HAD FAILED JUST FORWARD OF THE 90 DEG GEAR BOX.
NTSB Probable Cause
FAILURE OF THE AFT TAIL ROTOR DRIVE SHAFT.
Full Narrative
THE STUDENT PLT WAS ON AN APCH TO LAND ON A X-COUNTRY FLT, WHEN THE AFT TAIL ROTOR DRIVE SHAFT (PN: 47-644-187) FAILED AT ABOUT 40' AGL. HE RPRTD THE HELICOPTER BEGAN TO SPIN TO THE RIGHT, SO HE CLOSED THE THROTTLE & THE SPINNING STOPPED. HE PULLED UP ON THE COLLECTIVE TO CUSHION THE LANDING, BUT RAN OUT OF COLLECTIVE PITCH AT ABOUT 10' ABOVE THE GROUND. SUBSEQUENTLY, THE HELICOPTER TOUCHED DOWN HARD, DAMAGING THE TAIL ROTOR & TAIL BOOM. THE TAIL ROTOR DRIVE SHAFT HAD FAILED JUST FORWARD OF THE 90 DEG GEAR BOX.
Flight
Event TypeAccident
Event Time12:09 AST
Nearest AirportMercedita (0nm N)
Runway12
Runway Length5529 ft
Runway Width100 ft
Flight Plan FiledVFR
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftBell 47G
Tail NumberN955B
Aircraft CategoryHeli
DamageSubstantial
OperatorEsteves Arturo
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsFranklin · 6V-350 · Reciprocating · 235
Seats3
People & Injuries
Injury SummaryNo injuries (1 uninjured)
Fatal0
Serious0
Minor0
Uninjured1
Total1
Crew 1Age 48 · Third Class
Conditions
ConditionsVMC
LightDaylight
Wind130° @ 20 kt
Visibility15 sm
CeilingNone
Altimeter29.00 inHg
Observation Time15:58