Mechanical & Engine Failure · NTSB ERA21FA229

MUNSON ROGER J RV-8 — Van Cleve, KY

1 fatal Low-time pilot
DateMay 24, 2021
LocationVan Cleve, KY
AircraftMUNSON ROGER J RV-8 (amateur-built)
Purpose of flightPersonal
ConditionsDay · Visual Meteorological Cond
Phase / occurrenceEmergency descent Collision with terr/obj (non-CFIT)
Pilot age62
Pilot total time200 hrs · Low time
Time in typeUnknown
Fatalities1

Probable cause

A loss of engine power due to loss of engine oil pressure.

NTSB findings

  • Aircraft-Aircraft power plant-Engine (reciprocating)-Recip eng oil sys-Unknown/Not determined
  • Aircraft-Fluids/misc hardware-Fluids-Oil-Unknown/Not determined

What happened

During a cross-country flight at cruise altitude, the pilot reported a loss of engine oil pressure and loss of engine power to air traffic control and subsequently performed a forced landing to a field. The airplane impacted the ground and the wreckage was partially consumed by a post impact fire.

Examination of the wreckage revealed oil staining on a portion of the horizontal stabilizer and broken pieces of the windscreen that were found at the site. Examination of the engine revealed that with the exception of the oil sump, which had been partially consumed by the postimpact fire, the crankcase, cylinders were intact, and continuity of the crankshaft and valvetrain were confirmed. The examination also found that an oil line connecting the engine to an aftermarket oil valve had separated, though it could not be determined if the separation occurred prior to, or as a result of the airplane’s impact with the ground. Overall, the engine did not display signatures consistent with a catastrophic loss of engine power and accompanying breach of the engine crankcase. Given the pilot’s report of a loss of oil pressure (and loss of engine power), and the oil staining observed on the wreckage, it is likely that such a failure was imminent. Given the extent of the fire damage to the engine, the reason for the loss of oil pressure could not be determined.

A review of the pilot’s pathological information revealed the presence of ethanol, which was most likely from postmortem production rather than ingestion. Therefore, the presence of ethanol did not contribute to the circumstances of the accident.

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 →