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NTSB Report
March 10, 1991 · Bell 47G-5A · N59403
Farmington, CA
Overview
Report Status
Probable Cause
Event Type
Accident
Date
March 10, 1991
Injury Outcomes
No injuries (1 uninjured)
Location
Farmington, CA
Aircraft
Bell 47G-5A
Tail Number
N59403
Operator
Ag-Air
Injuries
None
Aircraft Damage
Substantial
NTSB Number
LAX91LA128
THE ENGINE POWER REDUCED DURING A PROCEDURE TURNAROUND AS THE AIRCRAFT WAS DISPENSING LIQUID FERTILIZER. THE HELICOPTER SETTLED INTO SOFT TERRAIN AND THE MAIN ROTOR BLADE SEVERED THE TAIL BOOM. THE HELICOPTER THEN IMPACTED THE GROUND. EXAMINATION OF THE ENGINE'S AIR FILTER DISCLOSED EVIDENCE OF LIQUID FERTILIZER CLOGGING THE FILTER.
NTSB Probable Cause
THE CONTAMINATION OF THE ENGINE INDUCTION AIR FILTER. SOFT TERRAIN DURING THE TOUCHDOWN WAS A FACTOR IN THE ACCIDENT.
Full Narrative
THE ENGINE POWER REDUCED DURING A PROCEDURE TURNAROUND AS THE AIRCRAFT WAS DISPENSING LIQUID FERTILIZER. THE HELICOPTER SETTLED INTO SOFT TERRAIN AND THE MAIN ROTOR BLADE SEVERED THE TAIL BOOM. THE HELICOPTER THEN IMPACTED THE GROUND. EXAMINATION OF THE ENGINE'S AIR FILTER DISCLOSED EVIDENCE OF LIQUID FERTILIZER CLOGGING THE FILTER.
Flight
Event TypeAccident
Event Time16:30 PST
Nearest Airport0nm
Runway0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftBell 47G-5A
Tail NumberN59403
Aircraft CategoryHeli
DamageSubstantial
OperatorAg-Air
Operating RulePart 137
Engines1
Engine TypeReciprocating
Engine DetailsLycoming · VO-435-81A · Reciprocating · 220
Seats3
People & Injuries
Injury SummaryNo injuries (1 uninjured)
Fatal0
Serious0
Minor0
Uninjured1
Total1
Crew 1Age 45 · Second Class
Conditions
ConditionsVMC
LightDaylight
WindCalm
Visibility10 sm
CeilingNone
Temperature / Dew Point0 C / 0 C
Altimeter0
Weather SourcePILO