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NTSB Report
August 26, 1992 · Helio H-391B · N4431U
Edmonds, WA
Overview
Report Status
Probable Cause
Event Type
Accident
Date
August 26, 1992
Injury Outcomes
No injuries (1 uninjured)
Location
Edmonds, WA
Aircraft
Helio H-391B
Tail Number
N4431U
Operator
Brown Christopher K
Injuries
None
Aircraft Damage
Destroyed
NTSB Number
SEA92LA191
THE PILOT INCREASED POWER TO INITIATE A CLIMB AND THE ENGINE PARTIALLY LOST POWER. HE DITCHED THE ACFT IN PUGET SOUND WHEN HE WAS UNABLE TO REACH AN AIRPORT OR THE SHORE FOR AN EMERGENCY LANDING. THE ACFT NOSED OVER ON TOUCHDOWN IN THE WATER. AN EXAM OF THE ENGINE AFTER THE ACCIDENT REVEALED THE NO 4 EXHAUST VALVE WAS SEIZED IN THE OPEN POSITION.
NTSB Probable Cause
THE PARTIAL LOSS OF ENGINE POWER WHEN AN EXHAUST VALVE SEIZED IN THE OPEN POSITION AND THE WATER WHERE THE PILOT WAS FORCED TO LAND, WHICH RESULTED IN AN ACFT NOSE OVER ON TOUCHDOWN.
Full Narrative
THE PILOT INCREASED POWER TO INITIATE A CLIMB AND THE ENGINE PARTIALLY LOST POWER. HE DITCHED THE ACFT IN PUGET SOUND WHEN HE WAS UNABLE TO REACH AN AIRPORT OR THE SHORE FOR AN EMERGENCY LANDING. THE ACFT NOSED OVER ON TOUCHDOWN IN THE WATER. AN EXAM OF THE ENGINE AFTER THE ACCIDENT REVEALED THE NO 4 EXHAUST VALVE WAS SEIZED IN THE OPEN POSITION.
Flight
Event TypeAccident
Event Time20:40 PDT
Nearest Airport0nm N
Runway0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftHelio H-391B
Tail NumberN4431U
Aircraft CategoryAir
DamageDestroyed
OperatorBrown Christopher K
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsLycoming · GO-435 · Reciprocating · 260
Seats4
People & Injuries
Injury SummaryNo injuries (1 uninjured)
Fatal0
Serious0
Minor0
Uninjured1
Total1
Crew 1Age 31 · First Class
Conditions
ConditionsVMC
LightDark Night
Wind350° @ 4 kt
Visibility75 sm
CeilingNone
Temperature / Dew Point50
Altimeter30.00 inHg
Observation Time03:45
Weather SourceWFAC