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NTSB Report
May 17, 1983 · Piper PA25 · N4521Y
Tomah, WI
Overview
Report Status
Preliminary report
Event Type
Accident
Date
May 17, 1983
Injury Outcomes
No injuries (1 uninjured)
Location
Tomah, WI
Aircraft
Piper PA25
Tail Number
N4521Y
Injuries
None
Aircraft Damage
Substantial
NTSB Number
CHI83LA219
THE ACFT LOST POWER AND MADE A FORCED LANDING IMMEDIATELY AFTER TAKEOFF ON AN AERIAL APPLICATION MISSION. THE LANDING GEAR COLLAPSED DURING THE LANDING. THE PILOT STATED THAT THE ACCIDENT OCCURRED ON THE 5TH FLT OF THE DAY AFTER TAKING OFF ON RUNWAY 27 AND WHEN CLIMBING TO 125 FT AGL THE ENGINE BEGAN TO LOSE POWER. THE PILOT REDUCED POWER AND LANDED STRAIGHT AHEAD 50 YDS OFF THE END OF TH TAKEOFF RUNWAY. AN EXAMINATION OF THE ENGINE REVEALED THAT THE LOWER PLUGS CONTAINED A DARK GREY DEPOSIT THAT BRIDGED THE ELECTRODES. THIS DEPOSIT WEAKENED THE SPARK PRODUCED BY THE PLUGS. WHEN CLEARED THEY PRODUCED A STRONGER SPARK.
Full Narrative
THE ACFT LOST POWER AND MADE A FORCED LANDING IMMEDIATELY AFTER TAKEOFF ON AN AERIAL APPLICATION MISSION. THE LANDING GEAR COLLAPSED DURING THE LANDING. THE PILOT STATED THAT THE ACCIDENT OCCURRED ON THE 5TH FLT OF THE DAY AFTER TAKING OFF ON RUNWAY 27 AND WHEN CLIMBING TO 125 FT AGL THE ENGINE BEGAN TO LOSE POWER. THE PILOT REDUCED POWER AND LANDED STRAIGHT AHEAD 50 YDS OFF THE END OF TH TAKEOFF RUNWAY. AN EXAMINATION OF THE ENGINE REVEALED THAT THE LOWER PLUGS CONTAINED A DARK GREY DEPOSIT THAT BRIDGED THE ELECTRODES. THIS DEPOSIT WEAKENED THE SPARK PRODUCED BY THE PLUGS. WHEN CLEARED THEY PRODUCED A STRONGER SPARK.
Flight
Event TypeAccident
Event Time17:00 CDT
Nearest AirportBOYERS (0nm)
Runway27
Runway Length3600 ft
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftPiper PA25
Tail NumberN4521Y
Aircraft CategoryAir
DamageSubstantial
Operating RulePart 137
Engines1
Engine TypeReciprocating
Engine DetailsLycoming · O-540 · Reciprocating · 250
Seats1
People & Injuries
Injury SummaryNo injuries (1 uninjured)
Fatal0
Serious0
Minor0
Uninjured1
Total1
Crew 1Age 39 · Second Class
Conditions
ConditionsVMC
LightDaylight
Wind270° @ 10 kt
CeilingNone
Temperature / Dew Point55 / 0 C
Altimeter0
Weather SourceWIT