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NTSB Report
August 31, 1983 · Hiller UH-12E · N173HA
Corwith, IA
Overview
Report Status
Preliminary report
Event Type
Accident
Date
August 31, 1983
Injury Outcomes
1 injury (1 minor injury)
Location
Corwith, IA
Aircraft
Hiller UH-12E
Tail Number
N173HA
Operator
Benson Flying Service
Injuries
Minor
Aircraft Damage
Destroyed
NTSB Number
MKC83LA207
WHILE EN ROUTE, THE PLT HEARD A CLANKING NOISE BEHIND HIM WHICH WAS FOLLOWED BY A SEVERE VIBRATION OF THE FLT CONTROLS. HE INITIATED AN AUTOROTATIVE DESCENT FROM 3000 FT. HE SAID THE HELICOPTER BEGAN TO ROLL LEFT, THEN RIGHTED ITSELF. THE HELICOPTER TOUCHED DOWN WITH A FORWARD SPEED OF ABOUT 50 MPH, THEN ROLLED & WAS DESTROYED. AN INVESTIGATION REVEALED THAT THE CONTROL ROTOR CUFF, PN 36124-3, HAD FAILED FROM FATIGUE.
Full Narrative
WHILE EN ROUTE, THE PLT HEARD A CLANKING NOISE BEHIND HIM WHICH WAS FOLLOWED BY A SEVERE VIBRATION OF THE FLT CONTROLS. HE INITIATED AN AUTOROTATIVE DESCENT FROM 3000 FT. HE SAID THE HELICOPTER BEGAN TO ROLL LEFT, THEN RIGHTED ITSELF. THE HELICOPTER TOUCHED DOWN WITH A FORWARD SPEED OF ABOUT 50 MPH, THEN ROLLED & WAS DESTROYED. AN INVESTIGATION REVEALED THAT THE CONTROL ROTOR CUFF, PN 36124-3, HAD FAILED FROM FATIGUE.
Flight
Event TypeAccident
Event Time16:45 CDT
Nearest Airport0nm N
Runway0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftHiller UH-12E
Tail NumberN173HA
Aircraft CategoryHeli
DamageDestroyed
OperatorBenson Flying Service
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsLycoming · VO-540-B1A · Reciprocating · 305
Seats1
People & Injuries
Injury Summary1 injury (1 minor injury)
Fatal0
Serious0
Minor1
Uninjured0
Total1
Crew 1Age 36 · Second Class
Conditions
ConditionsVMC
LightDaylight
Wind70° @ 8 kt
Visibility15 sm
CeilingNone
Temperature / Dew Point0 C
Altimeter0
Weather SourcePILO