Pilot Debrief

PIPER PA-28-140 near Allentown, PA — 2012-10-12

Final reportERA13LA025
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Date
2012-10-12
Location
Allentown, PA, USA
Airport
ABE
Aircraft
PIPER PA-28-140
Registration
N15037
Category
Airplane
Highest injury
None
Fatalities
0
Phase of flight
Initial climb

Probable cause

The operator's failure to perform magneto inspections per the manufacturer's recommendations and failure to comply with the engine manufacturer's recommended time interval for engine overhaul, which resulted in defects in the magnetos going undetected and the failure of the right magneto during initial climb.

NTSB narrative

During the initial climb, the engine lost partial power, and the flight instructor performed a forced landing into a cornfield. During a subsequent test-run of the engine, the engine would lose all power if only the right magneto was selected. Laboratory examination of the right magneto revealed that seven teeth from its drive gear were fractured and exhibited single-sided bending fatigue, consistent with applied force in one direction over a period of time. At the time of the accident, the engine had accumulated about 2,300 hours since overhaul, which had been completed about 7 years prior. The accident magnetos had not been replaced or serviced since they were installed during engine overhaul. The engine manufacturer recommended overhauling the engine every 2,000 hours or 12 years, which would have included replacing the magnetos with new or overhauled units. Additionally, a service bulletin issued by the magneto manufacturer recommended inspecting the magnetos every 500 hours; however, there was no evidence that an inspection was ever performed during the 2,300-hour life of the failed magneto.

Analysis

Primary failure mode
Engine power loss
First missed decision gate
Throttle lever not fully forward; could have checked before takeoff.

NTSB coding

Evidence available

  • Photos
  • 13 docket documents
View NTSB final reportView NTSB docket

Docket documents13

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