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NTSB Report
August 16, 1990 · Piper PA-23-160 · N4231P
Odell, IL
Overview
Report Status
Probable Cause
Event Type
Accident
Date
August 16, 1990
Injury Outcomes
No injuries (3 uninjured)
Location
Odell, IL
Aircraft
Piper PA-23-160
Tail Number
N4231P
Injuries
None
Aircraft Damage
Substantial
NTSB Number
CHI90FA233
DURING FLIGHT THE LEFT ENGINE BEGAN RUNNING ROUGH AND VIBRATING SEVERELY, AND IT WAS SHUT DOWN. THE PILOT WAS UNABLE TO MAINTAIN ALTITUDE ON THE RIGHT ENGINE AND A FORCED LANDING WAS MADE IN AN ALFALFA FIELD. EXAMINATION REVEALED THAT THE LEFT ENGINES RIGHT MAGNETO HAD AN ACCUMULATION OF OIL INSIDE ITS CASE. IN ADDITION, THE SPARK PLUG LEAD FROM THE LEFT MAGNETO FOR THE #1 CYLINDER WAS INTERNALLY DAMAGED. EXAMINATION OF THE RIGHT ENGINE REVEALED THAT THE INTAKE DUCT BETWEEN THE AIR FILTER AND THE CARBURETOR WAS DETERIORATED FROM EXPOSURE TO HOT EXHAUST PIPES. A 3' X 1/2' PIECE OF THE DUCT HAD SEPARATED AND WAS FOUND CAUGHT ON THE CARBURETOR VENTURI.
NTSB Probable Cause
A LOSS OF LEFT ENGINE POWER DUE TO OIL ACCUMULATION IN THE RIGHT MAGNETO AND A NON-USABLE SPARK LEAD FROM THE LEFT MAGNETO. IN ADDITION, THE RIGHT ENGINE WAS UNABLE TO PROVIDE ADEQUATE POWER TO MAINTAIN ALTITUDE DUE TO A PARTIAL BLOCKAGE IN THE CARBURETOR BY A SECTION OF AIR INTAKE DUCT WHICH CAUSED THE ENGINE TO RUN RICH.
Full Narrative
DURING FLIGHT THE LEFT ENGINE BEGAN RUNNING ROUGH AND VIBRATING SEVERELY, AND IT WAS SHUT DOWN. THE PILOT WAS UNABLE TO MAINTAIN ALTITUDE ON THE RIGHT ENGINE AND A FORCED LANDING WAS MADE IN AN ALFALFA FIELD. EXAMINATION REVEALED THAT THE LEFT ENGINES RIGHT MAGNETO HAD AN ACCUMULATION OF OIL INSIDE ITS CASE. IN ADDITION, THE SPARK PLUG LEAD FROM THE LEFT MAGNETO FOR THE #1 CYLINDER WAS INTERNALLY DAMAGED. EXAMINATION OF THE RIGHT ENGINE REVEALED THAT THE INTAKE DUCT BETWEEN THE AIR FILTER AND THE CARBURETOR WAS DETERIORATED FROM EXPOSURE TO HOT EXHAUST PIPES. A 3' X 1/2' PIECE OF THE DUCT HAD SEPARATED AND WAS FOUND CAUGHT ON THE CARBURETOR VENTURI.
Flight
Event TypeAccident
Event Time14:42 CDT
Nearest Airport0nm N
Runway0
Flight Plan FiledIFR
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftPiper PA-23-160
Tail NumberN4231P
Aircraft CategoryAir
DamageSubstantial
Operating RulePart 91
Engines2
Engine TypeReciprocating
Engine DetailsLycoming · O-320-B3B · Reciprocating · 160
Seats4
People & Injuries
Injury SummaryNo injuries (3 uninjured)
Fatal0
Serious0
Minor0
Uninjured3
Total3
Crew 1Age 22 · First Class
Conditions
ConditionsVMC
LightDaylight
Wind180° @ 8 kt
Visibility3 sm
CeilingOvercast 1000 ft
Temperature / Dew Point0 C / 0 C
Altimeter0
Observation Time20:45
Weather SourceWFAC