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NTSB Report
June 18, 1991 · Glasair SH-2-RG · N306AT
Visalia, CA
Overview
Report Status
Probable Cause
Event Type
Accident
Date
June 18, 1991
Injury Outcomes
2 injuries (2 minor injuries)
Location
Visalia, CA
Aircraft
Glasair SH-2-RG
Tail Number
N306AT
Operator
Frank R Sigler
Injuries
Minor
Aircraft Damage
Substantial
NTSB Number
LAX91LA265
THE CERTIFICATED PRIVATE PILOT/OWNER STATED THAT AN HOUR AND HALF INTO THE FLIGHT THE ENGINE STARTED TO RUN ROUGH AND LOST RPM. ALL INSTRUMENTS WERE IN THE GREEN. HE HEADED THE AIRCRAFT FOR A SUITABLE AIRPORT BUT THE ENGINE QUIT IN THE PATTERN. DUE TO WINDS HE WAS UNABLE TO MAKE THE RUNWAY. EXAMINATION OF THE ENGINE BY FAA INSPECTORS REVEALED THAT THE NUMBER 4 CYLINDER EXHAUST VALVE FAILED.
NTSB Probable Cause
TOTAL LOSS OF ENGINE POWER DUE TO THE FAILURE OF THE NUMBER 4 ENGINE EXHAUST VALVE.
Full Narrative
THE CERTIFICATED PRIVATE PILOT/OWNER STATED THAT AN HOUR AND HALF INTO THE FLIGHT THE ENGINE STARTED TO RUN ROUGH AND LOST RPM. ALL INSTRUMENTS WERE IN THE GREEN. HE HEADED THE AIRCRAFT FOR A SUITABLE AIRPORT BUT THE ENGINE QUIT IN THE PATTERN. DUE TO WINDS HE WAS UNABLE TO MAKE THE RUNWAY. EXAMINATION OF THE ENGINE BY FAA INSPECTORS REVEALED THAT THE NUMBER 4 CYLINDER EXHAUST VALVE FAILED.
Flight
Event TypeAccident
Event Time13:40 PDT
Nearest Airport0nm
Runway0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftGlasair SH-2-RG
Tail NumberN306AT
Aircraft CategoryAir
DamageSubstantial
OperatorFrank R Sigler
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsLycoming · IO-360-A1B · Reciprocating · 200
Seats2
People & Injuries
Injury Summary2 injuries (2 minor injuries)
Fatal0
Serious0
Minor2
Uninjured0
Total2
Crew 1Age 63 · Third Class
Conditions
ConditionsVMC
LightDaylight
Wind310° @ 20 kt
Visibility30 sm
CeilingNone
Temperature / Dew Point0 C / 0 C
Altimeter0
Weather SourcePILO