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NTSB Report
July 8, 1986 · Bell 47G-5 · N1316X
Porterville, CA
Overview
Report Status
Preliminary report
Event Type
Accident
Date
July 8, 1986
Injury Outcomes
1 injury (1 serious injury), 2 uninjured
Location
Porterville, CA
Aircraft
Bell 47G-5
Tail Number
N1316X
Injuries
Serious
Aircraft Damage
Substantial
NTSB Number
LAX86FVA11
DURING AN AERIAL APPLICATION FLIGHT THE PLT LOST CONTROL OF THE HELICOPTER AND COLLIDED WITH A BUILDING. EXAMINATION REVEALED THAT THE INSIDE DIAMETER OF THE TAIL ROTOR DRIVESHAFT WAS NOT COATED WITH ALUMINIZED LACQUER AS REQUIRED BY THE BELL FINISH PROCESS SPECIFICATION. THE BELL DRAWING REQUIRES TWO #2 SHORT PLUGS TO BE INSTALLED AT A SPECIFIED DISTANCE FROM EACH END OF THE TAIL ROTOR DRIVESHAFT AND THE END OF THE SHAFT TO BE SEALED OFF WITH ADHESIVE TO PROTECT THE SHAFT INSIDE DIAMETER FROM CORROSION. A DIMENSIONAL CHECK OF THE SHAFT REVEALED THAT THE PLUGS WERE NOT INSTALLED AT THE CORRECT DISTANCE FROM THE END OF THE SHAFT AS SPECIFIED IN THE DRAWING.
Full Narrative
DURING AN AERIAL APPLICATION FLIGHT THE PLT LOST CONTROL OF THE HELICOPTER AND COLLIDED WITH A BUILDING. EXAMINATION REVEALED THAT THE INSIDE DIAMETER OF THE TAIL ROTOR DRIVESHAFT WAS NOT COATED WITH ALUMINIZED LACQUER AS REQUIRED BY THE BELL FINISH PROCESS SPECIFICATION. THE BELL DRAWING REQUIRES TWO #2 SHORT PLUGS TO BE INSTALLED AT A SPECIFIED DISTANCE FROM EACH END OF THE TAIL ROTOR DRIVESHAFT AND THE END OF THE SHAFT TO BE SEALED OFF WITH ADHESIVE TO PROTECT THE SHAFT INSIDE DIAMETER FROM CORROSION. A DIMENSIONAL CHECK OF THE SHAFT REVEALED THAT THE PLUGS WERE NOT INSTALLED AT THE CORRECT DISTANCE FROM THE END OF THE SHAFT AS SPECIFIED IN THE DRAWING.
Flight
Event TypeAccident
Event Time09:15 PDT
Nearest Airport0nm N
Runway0
Runway Length0
Runway Width0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftBell 47G-5
Tail NumberN1316X
Aircraft CategoryHeli
DamageSubstantial
Operating RulePart 137
Engines1
Engine TypeReciprocating
Engine DetailsLycoming · VO-435-B1A · Reciprocating · 260
Seats3
People & Injuries
Injury Summary1 injury (1 serious injury), 2 uninjured
Fatal0
Serious1
Minor0
Uninjured2
Total3
Crew 1Age 57 · Second Class
Conditions
ConditionsVMC
LightDaylight
WindCalm
Visibility30 sm
CeilingNone
Temperature / Dew Point0 C / 0 C
Altimeter0
Weather SourcePILO