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NTSB Report
November 4, 1990 · Christen Industries A-1 · N9609G
Afton, WY
Overview
Report Status
Probable Cause
Event Type
Accident
Date
November 4, 1990
Injury Outcomes
No injuries (1 uninjured)
Location
Afton, WY
Aircraft
Christen Industries A-1
Tail Number
N9609G
Operator
Heiner Mark G
Injuries
None
Aircraft Damage
Substantial
NTSB Number
SEA91LA012
DURING A CROSS COUNTRY FLIGHT, THE AIRPLANE EXPERIENCED A LOSS OF ENGINE POWER. THE PILOT INITIATED A FORCED LANDING, DURING THE LANDING ROLL, THE AIRPLANE STRUCK A DITCH AND NOSED OVER. INSPECTION OF THE ENGINE REVEALED THAT THE CARBURETOR HEAT VALVE HAD BEEN SECURED IN THE COLD OR OFF POSITION. THIS MODIFICATION DID NOT ALLOW FOR THE CARBURETOR HEAT TO BE APPLIED. AT THE TIME OF THE ENGINE FAILURE, THE AIRPLANE WAS OPERATING IN ICING CONDITIONS. THERE WERE NO OTHER MECHANICAL FAILURES OR MALFUNCTIONS FOUND.
NTSB Probable Cause
AN IMPROPER MAINTENANCE MODIFICATION TO DISABLE THE CARBURETOR HEAT CONTROL BY UNKNOWN PERSONNEL.
Full Narrative
DURING A CROSS COUNTRY FLIGHT, THE AIRPLANE EXPERIENCED A LOSS OF ENGINE POWER. THE PILOT INITIATED A FORCED LANDING, DURING THE LANDING ROLL, THE AIRPLANE STRUCK A DITCH AND NOSED OVER. INSPECTION OF THE ENGINE REVEALED THAT THE CARBURETOR HEAT VALVE HAD BEEN SECURED IN THE COLD OR OFF POSITION. THIS MODIFICATION DID NOT ALLOW FOR THE CARBURETOR HEAT TO BE APPLIED. AT THE TIME OF THE ENGINE FAILURE, THE AIRPLANE WAS OPERATING IN ICING CONDITIONS. THERE WERE NO OTHER MECHANICAL FAILURES OR MALFUNCTIONS FOUND.
Flight
Event TypeAccident
Event Time16:40 MST
Nearest Airport0nm N
Runway0
Runway Length0
Runway Width0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftChristen Industries A-1
Tail NumberN9609G
Aircraft CategoryAir
DamageSubstantial
OperatorHeiner Mark G
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsLycoming · O-360-C1G · Reciprocating · 180
Seats2
People & Injuries
Injury SummaryNo injuries (1 uninjured)
Fatal0
Serious0
Minor0
Uninjured1
Total1
Crew 1Age 41 · Second Class
Conditions
ConditionsVMC
LightDaylight
WindCalm
Visibility10 sm
CeilingOvercast 5400 ft
Temperature / Dew Point0 C / 0 C
Altimeter0
Weather SourcePILO