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NTSB Report
July 7, 1991 · Cessna 140 · N3160N
Montague, CA
Overview
Report Status
Probable Cause
Event Type
Accident
Date
July 7, 1991
Injury Outcomes
No injuries (2 uninjured)
Location
Montague, CA
Aircraft
Cessna 140
Tail Number
N3160N
Operator
Jack W Potter
Injuries
None
Aircraft Damage
Substantial
NTSB Number
LAX91LA294
DURING CRUISE FLIGHT THE PILOT HEARD A LOUD BANGING NOISE COMING FROM THE ENGINE COMPARTMENT. THE PILOT REPORTED BEING UNABLE TO MAINTAIN ALTITUDE, AND HE MADE A FORCED LANDING. DURING ROLLOUT THE AIRPLANE COLLIDED WITH A BERM AND NOSED OVER. AN EXAMINATION OF THE ENGINE REVEALED THE NUMBER ONE CYLINDER'S EXHAUST VALVE WAS BROKEN. THE VALVE HAD BEEN IN USE FOR AT LEAST 973 OPERATIONAL HOURS PRIOR TO THE ACCIDENT.
NTSB Probable Cause
THE FAILURE OF AN EXHAUST VALVE IN THE ENGINE.
Full Narrative
DURING CRUISE FLIGHT THE PILOT HEARD A LOUD BANGING NOISE COMING FROM THE ENGINE COMPARTMENT. THE PILOT REPORTED BEING UNABLE TO MAINTAIN ALTITUDE, AND HE MADE A FORCED LANDING. DURING ROLLOUT THE AIRPLANE COLLIDED WITH A BERM AND NOSED OVER. AN EXAMINATION OF THE ENGINE REVEALED THE NUMBER ONE CYLINDER'S EXHAUST VALVE WAS BROKEN. THE VALVE HAD BEEN IN USE FOR AT LEAST 973 OPERATIONAL HOURS PRIOR TO THE ACCIDENT.
Flight
Event TypeAccident
Event Time12:45 PDT
Nearest Airport0nm N
Runway0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftCessna 140
Tail NumberN3160N
Aircraft CategoryAir
DamageSubstantial
OperatorJack W Potter
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsContinental · 85F · Reciprocating · 85
Seats2
People & Injuries
Injury SummaryNo injuries (2 uninjured)
Fatal0
Serious0
Minor0
Uninjured2
Total2
Crew 1Age 55 · Third Class
Conditions
ConditionsVMC
LightDaylight
WindCalm
Visibility30 sm
CeilingNone
Temperature / Dew Point0 C / 0 C
Altimeter0
Weather SourcePILO