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NTSB Report
April 6, 1991 · Cessna 150D · N4437U
San Ygnacio, TX
Overview
Report Status
Probable Cause
Event Type
Accident
Date
April 6, 1991
Injury Outcomes
2 injuries (2 serious injuries)
Location
San Ygnacio, TX
Aircraft
Cessna 150D
Tail Number
N4437U
Operator
Juan a Guevera Sr
Injuries
Serious
Aircraft Damage
Destroyed
NTSB Number
FTW91LA061
THE PIC ASKED THE PASSENGER RIDING IN THE LEFT SEAT IF HE WANTED TO SEE HOW THE AG PILOTS FLEW. HE REDUCED POWER TO IDLE AND DOVE DOWN TOWARD AN OPEN FIELD. AFTER TRAVERSING THE FIELD THE PILOT ADDED POWER AND THE PASSENGER HEARD A 'POP OR BANG' NOISE FROM THE ENGINE AND THE PILOT SAID 'OH MY GOD'. THE AIRPLANE SUBSEQUENTLY IMPACTED IN THE FIELD IN A SHALLOW NOSE DOWN ATTITUDE AND A SLIGHT LEFT BANK AND CART-WHEELED. INVESTIGATION REVEALED THAT CONDITIONS WERE PRESENT FOR CARBURETOR ICING AND THAT THE CARBURETOR ACCELERATOR PUMP WAS NOT ACTUATING SMOOTHLY. THE CARBURETOR HEAT CONTROL WAS FOUND JAMMED TO THE FULL ON POSITION FOLLOWING THE ACCIDENT; HOWEVER, IT COULD NOT BE DETERMINED IF THAT WAS THE CONDITION PRIOR TO IMPACT.
NTSB Probable Cause
POWER LOSS DUE TO CARBURETOR ICE AND A MALFUNCTIONING CARBURETOR HEAT CONTROL AND THE PILOT'S LOSS OF CONTROL OF THE AIRPLANE.
Full Narrative
THE PIC ASKED THE PASSENGER RIDING IN THE LEFT SEAT IF HE WANTED TO SEE HOW THE AG PILOTS FLEW. HE REDUCED POWER TO IDLE AND DOVE DOWN TOWARD AN OPEN FIELD. AFTER TRAVERSING THE FIELD THE PILOT ADDED POWER AND THE PASSENGER HEARD A 'POP OR BANG' NOISE FROM THE ENGINE AND THE PILOT SAID 'OH MY GOD'. THE AIRPLANE SUBSEQUENTLY IMPACTED IN THE FIELD IN A SHALLOW NOSE DOWN ATTITUDE AND A SLIGHT LEFT BANK AND CART-WHEELED. INVESTIGATION REVEALED THAT CONDITIONS WERE PRESENT FOR CARBURETOR ICING AND THAT THE CARBURETOR ACCELERATOR PUMP WAS NOT ACTUATING SMOOTHLY. THE CARBURETOR HEAT CONTROL WAS FOUND JAMMED TO THE FULL ON POSITION FOLLOWING THE ACCIDENT; HOWEVER, IT COULD NOT BE DETERMINED IF THAT WAS THE CONDITION PRIOR TO IMPACT.
Flight
Event TypeAccident
Event Time10:55 CST
Nearest Airport0nm N
Runway0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftCessna 150D
Tail NumberN4437U
Aircraft CategoryAir
DamageDestroyed
OperatorJuan a Guevera Sr
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsContinental · O-200-A · Reciprocating · 100
Seats2
People & Injuries
Injury Summary2 injuries (2 serious injuries)
Fatal0
Serious2
Minor0
Uninjured0
Total2
Crew 1Age 59 · Second Class
Conditions
ConditionsVMC
LightDaylight
Wind10° @ 6 kt
Visibility8 sm
CeilingOvercast 3500 ft
Temperature / Dew Point68 F / 57
Altimeter30.00 inHg
Weather SourceWIT