What happened
On November 30, 2013, a Piper PA-28-161, registration N8878E, was being flown from Pryor Field Regional Airport in Decatur, Alabama, to Abernately Field in Pulaski, Tennessee. The pilot was in the process of moving the recently purchased aircraft to its new permanent base.
A witness observed the aircraft performing high-speed, knife-edge turns at an altitude of less than 100 feet. After several minutes of maneuvering, the witness heard a "pop" and observed the engine quit. The aircraft subsequently nosed down, striking a power pole approximately 10 feet above the ground before hitting the ground and sliding into an abandoned house.
GPS data confirmed the aircraft was maneuvering at low altitudes near a small community. The final recorded data point showed the aircraft at 1,442 feet MSL during a climbing left turn, with a subsequent minimum rate of descent calculated at 1,920 feet per minute.
The investigation
Investigators examined the engine and found that the time since major overhaul (TSMO) was 2,203 hours, exceeding the manufacturer's recommended 2,000-hour interval. A review of maintenance logs revealed a period of six years where no maintenance was recorded.
Post-accident examination of the four engine cylinders via borescope revealed extensive deposits of combustion by-products on the exhaust valves, guides, and valve seats. Additionally, the propeller showed no signs of power at the time of impact, as one blade was straight and the other was bent 90 degrees aft.
Findings
- The engine suffered a stuck exhaust valve, which caused a total loss of power.
- The pilot's decision to maneuver at a very low altitude significantly reduced available landing options once the engine failed.
- Poor long-term engine maintenance contributed to the buildup of combustion by-products that led to the valve failure.
- The pilot's underlying attention deficit hyperactivity disorder (ADHD) contributed to poor aeronautical decision-making.