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NTSB Report
September 11, 1991 · Texas Helicopter M74 · N43921
Farmington, CA
Overview
Report Status
Probable Cause
Event Type
Accident
Date
September 11, 1991
Injury Outcomes
1 injury (1 fatality)
Location
Farmington, CA
Aircraft
Texas Helicopter M74
Tail Number
N43921
Operator
Ag-Air
Injuries
Fatal
Aircraft Damage
Destroyed
NTSB Number
LAX91LA388
AFTER THE HELICOPTER WAS RELOADED WITH 500 LBS OF SULFUR, THE PILOT TOOK OFF & DEPARTED TO THE NORTHWEST AT AN ALTITUDE OF ABOUT 100 FT TO CONTINUE THE APPLICATION MISSION. THE GROUND CREW REPORTED THAT SHORTLY AFTER DEPARTURE, THE ENGINE BACKFIRED SEVERAL TIMES & THE HELICOPTER BEGAN SETTLING TAIL FIRST TO THE GROUND. GROUND CONTACT SEPARATED THE TAIL BOOM FROM THE HELICOPTER & IT ROTATED TO THE LEFT. THE SKIDS SEPARATED & THE RIGHT SULFUR TANK RUPTURED. A SULFUR FIRE ERUPTED. THE PILOT EXITED THE COCKPIT ON THE RIGHT SIDE & WAS STRUCK BY THE MAIN ROTOR. THE HELICOPTER WAS LOADED 69 LBS OVER ITS MAXIMUM ALLOWABLE GROSS WEIGHT. NO PREIMPACT PART FAILURE OF THE HELICOPTER OR ENGINE WAS FOUND. TESTS OF THE PILOT'S BLOOD SHOWED 0.009 UG/ML OF 11-NOR-DELTA-9-TETRAHYRDROCANNABINOL & 0.012 UG/ML OF 11-NOR-DELTA-9-THC-9-CARBOXYLIC ACID. A TEST OF HIS URINE DETECTED 0.129 UG/ML OF 11-NOR-DELTA-9-CARBOXYLIC ACID.
NTSB Probable Cause
LOSS OF ENGINE POWER FOR AN UNDETERMINED REASON. FACTORS RELATED TO THE ACCIDENT WERE: THE EXCESSIVE GROSS WEIGHT OF THE HELICOPTER, AND THE PILOT'S IMPROPER USE OF FLIGHT CONTROLS DUE TO IMPAIRMENT FROM USE OF A DRUG (MARIJUANNA).
Full Narrative
AFTER THE HELICOPTER WAS RELOADED WITH 500 LBS OF SULFUR, THE PILOT TOOK OFF & DEPARTED TO THE NORTHWEST AT AN ALTITUDE OF ABOUT 100 FT TO CONTINUE THE APPLICATION MISSION. THE GROUND CREW REPORTED THAT SHORTLY AFTER DEPARTURE, THE ENGINE BACKFIRED SEVERAL TIMES & THE HELICOPTER BEGAN SETTLING TAIL FIRST TO THE GROUND. GROUND CONTACT SEPARATED THE TAIL BOOM FROM THE HELICOPTER & IT ROTATED TO THE LEFT. THE SKIDS SEPARATED & THE RIGHT SULFUR TANK RUPTURED. A SULFUR FIRE ERUPTED. THE PILOT EXITED THE COCKPIT ON THE RIGHT SIDE & WAS STRUCK BY THE MAIN ROTOR. THE HELICOPTER WAS LOADED 69 LBS OVER ITS MAXIMUM ALLOWABLE GROSS WEIGHT. NO PREIMPACT PART FAILURE OF THE HELICOPTER OR ENGINE WAS FOUND. TESTS OF THE PILOT'S BLOOD SHOWED 0.009 UG/ML OF 11-NOR-DELTA-9-TETRAHYRDROCANNABINOL & 0.012 UG/ML OF 11-NOR-DELTA-9-THC-9-CARBOXYLIC ACID. A TEST OF HIS URINE DETECTED 0.129 UG/ML OF 11-NOR-DELTA-9-CARBOXYLIC ACID.
Flight
Event TypeAccident
Event Time07:58 PDT
Nearest Airport0nm N
Runway0
Flight Plan FiledNone
Aircraft FireGrd
Aircraft ExplosionNo
Aircraft
AircraftTexas Helicopter M74
Tail NumberN43921
Aircraft CategoryHeli
DamageDestroyed
OperatorAg-Air
Operating RulePart 137
Engines1
Engine TypeReciprocating
Engine DetailsLycoming · VO-435 · Reciprocating · 240
Seats1
People & Injuries
Injury Summary1 injury (1 fatality)
Fatal1
Serious0
Minor0
Uninjured0
Total1
Crew 1Age 39 · Second Class
Conditions
ConditionsVMC
LightDaylight
Wind310° @ 7 kt
Visibility10 sm
CeilingNone
Temperature / Dew Point61 F / 0 C
Altimeter0
Weather SourceWIT