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NTSB Report
July 5, 1983 · Hiller UH-12E · N4028K
Brooten, MN
Overview
Report Status
Preliminary report
Event Type
Accident
Date
July 5, 1983
Injury Outcomes
No injuries (1 uninjured)
Location
Brooten, MN
Aircraft
Hiller UH-12E
Tail Number
N4028K
Injuries
None
Aircraft Damage
Substantial
NTSB Number
CHI83LA297
THE HELICOPTER HAD JUST LIFTED OFF OF THE FLATBED OF A TRUCK WHEN IT STARTED TO SPIN. THE PLT LOWERED THE COLLECTIVE, REDUCED THE POWER & LANDED BESIDE THE TRUCK. DURING TOUCHDOWN, THE MAIN ROTOR BLADES STRUCK THE TRUCK. AN INVESTIGATION REVEALED THAT THE THRUST BEARING, PN 25200-3, IN THE TAIL ROTOR DRIVE WAS INSTALLED BACKWARDS. THIS ALLOWED THE BEVELED DRIVE GEAR TO MOVE FORWARD & BECOME DISENGAGED FROM THE TAIL ROTOR DRIVE GEAR.
Full Narrative
THE HELICOPTER HAD JUST LIFTED OFF OF THE FLATBED OF A TRUCK WHEN IT STARTED TO SPIN. THE PLT LOWERED THE COLLECTIVE, REDUCED THE POWER & LANDED BESIDE THE TRUCK. DURING TOUCHDOWN, THE MAIN ROTOR BLADES STRUCK THE TRUCK. AN INVESTIGATION REVEALED THAT THE THRUST BEARING, PN 25200-3, IN THE TAIL ROTOR DRIVE WAS INSTALLED BACKWARDS. THIS ALLOWED THE BEVELED DRIVE GEAR TO MOVE FORWARD & BECOME DISENGAGED FROM THE TAIL ROTOR DRIVE GEAR.
Flight
Event TypeAccident
Event Time08:00 CDT
Nearest Airport0nm N
Runway0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftHiller UH-12E
Tail NumberN4028K
Aircraft CategoryHeli
DamageSubstantial
Operating RulePart 137
Engines1
Engine TypeTurboshaft
Engine DetailsAllison · 250-C20B · Turboshaft · 305
Seats3
People & Injuries
Injury SummaryNo injuries (1 uninjured)
Fatal0
Serious0
Minor0
Uninjured1
Total1
Crew 1Age 44 · Second Class
Conditions
ConditionsVMC
LightDaylight
Wind360° @ 4 kt
Visibility25 sm
CeilingNone
Temperature / Dew Point61 F / 0 C
Altimeter0
Weather SourcePILO