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NTSB Report
April 5, 1991 · Piper PA-28-161 · N2366W
Schaumburg, IL
Overview
Report Status
Probable Cause
Event Type
Accident
Date
April 5, 1991
Injury Outcomes
1 injury (1 minor injury), 3 uninjured
Location
Schaumburg, IL
Aircraft
Piper PA-28-161
Tail Number
N2366W
Operator
Northwest Flyers
Injuries
Minor
Aircraft Damage
Substantial
NTSB Number
CHI91LA121
THE AIRPLANE'S ENGINE SEIZED AT 70 FEET ON TAKEOFF CLIMB, AND THE PILOT EXECUTED A FORCED LANDING. THE ENGINE HAD RECENTLY UNDERGONE REPLACEMENT OF THE NUMBER 1 CYLINDER; NO OTHER PARTS WERE CHANGED. PAINT MARKS ON THE REPLACEMENT CYLINDER INDICATED IT HAD BEEN CHROME PLATED TO STANDARD BORE. THE 3 REMAINING CYLINDERS AND ALL PISTONS WERE MARKED 0.010 OVERSIZE. THE OPERATOR'S DIRECTOR OF MAINTENANCE OBTAINED THE REPLACEMENT PART AND PROVIDED IT TO THE MECHANIC. THE OPERATOR'S MECHANIC STATED HE WAS UNAWARE WHAT THE CYLINDERS' COLOR MARKS SIGNIFIED AND HAD NOT MEASURED MATCHING PARTS DURING REPLACEMENT.
NTSB Probable Cause
THE MECHANIC'S NOT UNDERSTANDING THE IDENTIFYING MARKS ON THE REPLACEMENT PART. A FACTOR IN THE ACCIDENT WAS THAT THE MECHANIC WAS PROVIDED WITH AN IMPROPER PART.
Full Narrative
THE AIRPLANE'S ENGINE SEIZED AT 70 FEET ON TAKEOFF CLIMB, AND THE PILOT EXECUTED A FORCED LANDING. THE ENGINE HAD RECENTLY UNDERGONE REPLACEMENT OF THE NUMBER 1 CYLINDER; NO OTHER PARTS WERE CHANGED. PAINT MARKS ON THE REPLACEMENT CYLINDER INDICATED IT HAD BEEN CHROME PLATED TO STANDARD BORE. THE 3 REMAINING CYLINDERS AND ALL PISTONS WERE MARKED 0.010 OVERSIZE. THE OPERATOR'S DIRECTOR OF MAINTENANCE OBTAINED THE REPLACEMENT PART AND PROVIDED IT TO THE MECHANIC. THE OPERATOR'S MECHANIC STATED HE WAS UNAWARE WHAT THE CYLINDERS' COLOR MARKS SIGNIFIED AND HAD NOT MEASURED MATCHING PARTS DURING REPLACEMENT.
Flight
Event TypeAccident
Event Time11:00 CST
Nearest AirportSchuamburg Air Park (0nm W)
Runway0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftPiper PA-28-161
Tail NumberN2366W
Aircraft CategoryAir
DamageSubstantial
OperatorNorthwest Flyers
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsLycoming · O-320-D3G · Reciprocating · 160
Seats4
People & Injuries
Injury Summary1 injury (1 minor injury), 3 uninjured
Fatal0
Serious0
Minor1
Uninjured3
Total4
Crew 1Age 24 · First Class
Conditions
ConditionsVMC
LightDaylight
Wind210° @ 11 kt
Visibility7 sm
CeilingNone
Temperature / Dew Point70 F / 54
Altimeter30.00 inHg
Observation Time17:00
Weather SourceWFAC