Mechanical & Engine Failure · NTSB CEN23FA410

SONEX AIRCRAFT SONEX — Dowagiac, MI

1 fatal
DateSeptember 10, 2023
LocationDowagiac, MI
AircraftSONEX AIRCRAFT SONEX (amateur-built)
Purpose of flightPersonal
ConditionsDay · Visual Meteorological Cond
Phase / occurrenceLanding Off-field or emergency landing
Pilot age82
Pilot total time736 hrs · Building experience
Time in typeUnknown
Fatalities1

Probable cause

The total loss of engine power due to the failure of the ignition distributor rotor.

NTSB findings

  • Aircraft-Aircraft power plant-Ignition system-Magneto/distributor-Failure

What happened

The pilot departed for a local flight and an alert notice (ALNOT) was issued when the pilot did not return. A search effort concluded four days later when the wreckage was found in a heavily wooded area about 4 miles from the departure airport. No ADS-B data associated with the airplane, or the accident flight was available. At the time of the on-scene examination, the transponder was observed in the OFF position.

Impact signatures on the propeller were consistent with the propeller not rotating at impact. Examination of the engine revealed that the ignition distributor rotor was fractured and disconnected from its driveshaft. This resulted in a total loss of engine power when the ignition system became inoperative due to the rotor failure. No other preimpact mechanical malfunctions or failures were found with the airframe or engine.

An editorial "what led to it / how to avoid it" analysis for this accident is generated separately and will appear here.

View the official NTSB docket →