PIPER PA-24-250 — Athens, GA

What happened

The pilot had recently purchased the airplane and wanted to fly with an instructor to familiarize himself with it before flying home to Texas. In the days before the accident, the pilot began two flights with a flight instructor in North Carolina in the accident airplane; however, both flights were cut short because the airplane was not producing full power and the engine was backfiring. On the day of the accident, the instructor contacted the accident pilot to inquire about the troubleshooting. The pilot reported, and logbook entries confirmed, that the spark plugs were cleaned and the fuel servo was adjusted, and that the airplane was returned to service. The pilot also stated to the instructor that he planned to depart to Texas that afternoon. When the instructor suggested that the pilot wait and get more experience in the airplane, the pilot stated that he “felt capable” and was departing in order to “beat the weather.”

The accident occurred on the first leg of the pilot’s return flight to Texas. Automatic dependent surveillance – broadcast (ADS-B) data revealed that, about 2 hours and 20 minutes after departure, the pilot performed two 360° turns before proceeding toward a nearby airport, where he contacted the tower controller and received a landing clearance. About one mile from the runway, the pilot declared mayday and reported a loss of engine power. No further transmissions were received; the airplane impacted terrain and a postimpact fire ensued. Examination of the engine did not reveal any evidence of preimpact mechanical malfunctions or failures; however, the examination was limited in scope due to impact damage and thermal damage sustained in the postcrash fire.

Recorded engine data revealed that the oil pressure briefly dropped to zero about 11 to 15 minutes before the reported loss of engine power, which corresponded with the two circles the pilot performed before contacting the tower controller; however, the pilot did not communicate any engine issues before the mayday call.

Review of maintenance records revealed several entries regarding loss of manifold pressure or backfiring, starting several years before the accident. During the six years before the accident, the airplane accumulated about 22 hours. The most recent engine overhaul was completed almost 33 years before the accident. The manufacturer’s recommended time between engine overhaul was 12 calendar years. Given the repeated, documented maintenance issues before departure and for years before the accident, it is likely that the loss of engine power occurred due to an undiagnosed engine issue that the investigation was not able to identify.

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