Piper PA-32-301T N8266D accident near Kingfisher, Oklahoma

Probable cause

An oil leak of undetermined origin that resulted in an in-flight engine compartment fire and subsequent loss of airplane control.

NTSB analysis

The instructional flight was to familiarize the pilot with newly installed avionics. Recorded flight and engine monitor data showed the airplane departed the airport and was maneuvering when the data ended about 28 minutes after departure. Witness video showed the airplane with a trail of thick black smoke before its impact with the ground. Engine monitor data showed that the engine’s operational parameters were normal until about 2 minutes before the end of the flight, when the oil pressure dropped to zero. Shortly after, several recorded parameters went offline. The recorded outside air temperature increased from about 10° C to over 800° C before the end of the data.

Debris found on the engine’s oil suction screen was consistent with the material for a magneto drive cushion that was found within the oil sump. No other anomalies were found with respect to the engine.

Oil streaking opposite the direction of flight on the airplane’s horizontal stabilator was consistent with a significant oil leak. No other anomalies with respect to the airplane were discovered; however, the amount of impact and fire damage to the airplane impeded comprehensive examination. The witness video, oil streaking, and engine monitor data were all consistent with an engine compartment fire due to an oil leak. The extent of the impact and fire damage precluded determination of the exact source of the oil leak.

Although toxicology testing of specimens from the flight instructor revealed several drugs that are not approved for pilot use, or that are generally used for disqualifying conditions, the nature of the accident and the presence of an additional qualified pilot in the cockpit suggests that the flight instructor’s use of these drugs had no bearing on the outcome of the accident flight.

Text from the NTSB. Open the NTSB docket for CEN23FA079 for the full record.