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NTSB Report
July 23, 1987 · Hiller 12E · N67139
Ulysess, KS
Overview
Report Status
Preliminary report
Event Type
Accident
Date
July 23, 1987
Injury Outcomes
1 injury (1 minor injury)
Location
Ulysess, KS
Aircraft
Hiller 12E
Tail Number
N67139
Operator
Tri Rotor Spray
Injuries
Minor
Aircraft Damage
Substantial
NTSB Number
MKC87LA145
DURING A HELICOPTER AERIAL APPLICATION OPERATION, ACFT SUFFERED A MAIN ROTOR SYSTEM HUB FAILURE. PIC WAS UNABLE TO CONTROL THE ACFT AND AN UNCONTROLLED DESCENT RESULTED. ACFT STRUCK THE TERRAIN AND WAS SUBSTANTIALLY DAMAGED AND THE PIC SUFFERED MINOR INJURIES. PIC STATED THAT THE COMPLETE ROTOR HEAD, BLADES AND PADDLES, HAD JUST BEEN REINSTALLED, AND AFTER A FLIGHT OF LESS THAN ONE MILE, THE FAILURE OCCURRED. PIC FURTHER STATED THAT THE LINKAGE PIN THAT GOES THROUGH THE MAST AND PITCH CHANGE MECHANISM WAS NOT ALIGNED CAUSING THE FAILURE.
Full Narrative
DURING A HELICOPTER AERIAL APPLICATION OPERATION, ACFT SUFFERED A MAIN ROTOR SYSTEM HUB FAILURE. PIC WAS UNABLE TO CONTROL THE ACFT AND AN UNCONTROLLED DESCENT RESULTED. ACFT STRUCK THE TERRAIN AND WAS SUBSTANTIALLY DAMAGED AND THE PIC SUFFERED MINOR INJURIES. PIC STATED THAT THE COMPLETE ROTOR HEAD, BLADES AND PADDLES, HAD JUST BEEN REINSTALLED, AND AFTER A FLIGHT OF LESS THAN ONE MILE, THE FAILURE OCCURRED. PIC FURTHER STATED THAT THE LINKAGE PIN THAT GOES THROUGH THE MAST AND PITCH CHANGE MECHANISM WAS NOT ALIGNED CAUSING THE FAILURE.
Flight
Event TypeAccident
Event Time05:45 MDT
Nearest Airport0nm N
Runway0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftHiller 12E
Tail NumberN67139
Aircraft CategoryHeli
DamageSubstantial
OperatorTri Rotor Spray
Operating RulePart 137
Engines1
Engine TypeReciprocating
Engine DetailsLycoming · O-540 · Reciprocating · 305
Seats1
People & Injuries
Injury Summary1 injury (1 minor injury)
Fatal0
Serious0
Minor1
Uninjured0
Total1
Crew 1Age 34 · Second Class
Conditions
ConditionsVMC
LightDaylight
Wind200° @ 13 kt
Visibility20 sm
CeilingNone
Temperature / Dew Point70 F / 0 C
Altimeter0
Weather SourcePILO