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NTSB Report
October 10, 1986 · Hughes 500-D · N58239
Seattle, WA
Overview
Report Status
Preliminary report
Event Type
Accident
Date
October 10, 1986
Injury Outcomes
No injuries (2 uninjured)
Location
Seattle, WA
Aircraft
Hughes 500-D
Tail Number
N58239
Injuries
None
Aircraft Damage
Substantial
NTSB Number
SEA87LA007
DURING A PRACTICE AUTOROTATION A LOSS OF POWER OCCURRED. THE PILOT ATTEMPTED ENGINE RECOVERY BUT WAS UNABLE TO RESULTING IN A HARD LANDING IN WHICH THE MAIN ROTOR BLADE FLEXED, SEVERING THE TAIL BOOM. THE THROTTLE LINKAGE ON THE PILOTS SIDE WAS FOUND TO HAVE BEEN OUT OF ADJUSTMENT, CAUSING THE ENGINE POWER TO FALL BELOW IDLE.
Full Narrative
DURING A PRACTICE AUTOROTATION A LOSS OF POWER OCCURRED. THE PILOT ATTEMPTED ENGINE RECOVERY BUT WAS UNABLE TO RESULTING IN A HARD LANDING IN WHICH THE MAIN ROTOR BLADE FLEXED, SEVERING THE TAIL BOOM. THE THROTTLE LINKAGE ON THE PILOTS SIDE WAS FOUND TO HAVE BEEN OUT OF ADJUSTMENT, CAUSING THE ENGINE POWER TO FALL BELOW IDLE.
Flight
Event TypeAccident
Event Time08:50 PDT
Nearest AirportBoeing Field (0nm N)
Runway31L
Runway Length10000 ft
Runway Width200 ft
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftHughes 500-D
Tail NumberN58239
Aircraft CategoryHeli
DamageSubstantial
Operating RulePart 91
Engines1
Engine TypeTurboshaft
Engine DetailsAllison · 250-C20B · Turboshaft · 375
Seats5
People & Injuries
Injury SummaryNo injuries (2 uninjured)
Fatal0
Serious0
Minor0
Uninjured2
Total2
Crew 1Age 36 · Second Class
Conditions
ConditionsVMC
LightDaylight
Wind360° @ 7 kt
Visibility7 sm
CeilingNone
Temperature / Dew Point61 F / 0 C
Altimeter0
Weather SourcePILO