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NTSB Report
August 1, 1991 · Piper PA-12 · N4436M
Alton, NH
Overview
Report Status
Probable Cause
Event Type
Accident
Date
August 1, 1991
Injury Outcomes
No injuries (3 uninjured)
Location
Alton, NH
Aircraft
Piper PA-12
Tail Number
N4436M
Operator
William Grahn
Injuries
None
Aircraft Damage
Substantial
NTSB Number
NYC91LA200
THE PILOT REDUCED POWER AND DESCENDED TO 2000 FEET. WHEN HE APPLIED POWER, THE ENGINE RPM BEGAN TO DROP. HE USED CARB HEAT, BUT THE RPM DROP CONTINUED. HE LANDED THE AIRPLANE IN TREES. THE PILOT SAID, 'I BELIEVE IT WAS CARB ICE. AFTER LIVING IN THE...DESERT FOR 5 YEARS, I'D FORGOTTEN HOW EASY IT WAS TO FORM BACK HERE.' THE FAA CHART, 'CONDITIONS FAVORING CARB ICE FORMATION,' SHOWS THE EXISTING TEMPERATURE/DEW POINT COULD PRODUCE 'SERIOUS ICING AT CRUISE POWER.' THE PILOT HAD A TOTAL OF 1.5 HOURS FLIGHT TIME IN THE PA-12.
NTSB Probable Cause
THE PILOT'S IMPROPER USE OF CARBURETOR HEAT, WHICH RESULTED IN A LOSS OF ENGINE POWER.
Full Narrative
THE PILOT REDUCED POWER AND DESCENDED TO 2000 FEET. WHEN HE APPLIED POWER, THE ENGINE RPM BEGAN TO DROP. HE USED CARB HEAT, BUT THE RPM DROP CONTINUED. HE LANDED THE AIRPLANE IN TREES. THE PILOT SAID, 'I BELIEVE IT WAS CARB ICE. AFTER LIVING IN THE...DESERT FOR 5 YEARS, I'D FORGOTTEN HOW EASY IT WAS TO FORM BACK HERE.' THE FAA CHART, 'CONDITIONS FAVORING CARB ICE FORMATION,' SHOWS THE EXISTING TEMPERATURE/DEW POINT COULD PRODUCE 'SERIOUS ICING AT CRUISE POWER.' THE PILOT HAD A TOTAL OF 1.5 HOURS FLIGHT TIME IN THE PA-12.
Flight
Event TypeAccident
Event Time14:30 EDT
Nearest Airport0nm N
Runway0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftPiper PA-12
Tail NumberN4436M
Aircraft CategoryAir
DamageSubstantial
OperatorWilliam Grahn
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsLycoming · O-320C · Reciprocating · 108
Seats3
People & Injuries
Injury SummaryNo injuries (3 uninjured)
Fatal0
Serious0
Minor0
Uninjured3
Total3
Crew 1Age 39 · Third Class
Conditions
ConditionsVMC
LightDaylight
Wind180° @ 6 kt
Visibility35 sm
CeilingNone
Temperature / Dew Point52
Altimeter0
Weather SourcePILO