History of Flight
On June 10, 2020, about 1631 central daylight time, a Piper PA-32RT-300T, registration N543GS, was destroyed when it impacted terrain near Selma, Alabama. The commercial pilot and a pilot-rated passenger sustained fatal injuries. The flight was conducted under Title 14 Code of Federal Regulations Part 91 as a business trip.
The airplane had been fueled with 55 gallons of fuel prior to departure from Walker County Airport – Bevill Field (JFX) in Jasper, Alabama. According to FAA air traffic control communications and radar data, the airplane departed JFX at 1543 with Pensacola International Airport (PNS) in Pensacola, Florida, as the intended destination. After takeoff, the airplane climbed to a cruise altitude of 15,000 ft mean sea level. Approximately 40 minutes into the flight, the pilot reported an engine "fluctuation" to the controller and requested a diversion to Craig Field Airport (SEM) in Selma, Alabama. The controller cleared the airplane to SEM. The pilot indicated that the propeller was turning, but the airplane had experienced a total loss of engine power. Shortly after, while descending toward SEM, the pilot reported a "fire as well." When the airplane was about 3 miles from SEM and at about 3,100 ft msl, radar and voice communications were lost.
Aircraft Information
The airplane was manufactured in 1978. At the time of the accident, the tachometer indicated 732.7 hours, and the engine had accumulated 1,726.9 hours since major overhaul. The most recent annual inspection, completed on March 29, 2020, at 723.4 tach hours, included an oil change and oil filter replacement. A discrepancy noted on the work order stated that the "oil temp probe is not reading correctly." According to the mechanic, the oil temperature probe and oil lines were replaced. When asked if the oil suction screen was cleaned during the annual inspection, the mechanic responded that the oil cooler was cleaned, flushed, and reinstalled.
On May 29, 2020, at 726.0 tach hours, a discrepancy indicated the airplane was "running rough and low power." The maintenance entry noted that cylinder No. 4 was replaced, and the airplane was returned to service with no discrepancies. On June 9, 2020, at 728.2 tach hours, a discrepancy listed "oil pressure low." The mechanic adjusted the oil pressure by turning the regulator screw one turn and re-safety wired the nut. The airplane was flown and returned to service with no discrepancies.
Examination of the engine maintenance logbook revealed that the most recent documented cleaning of the oil suction screen was on July 17, 2009, at which time the engine had 1,178.5 hours since major overhaul. The engine's operating manual specified cleaning the oil suction screen at each 50-hour inspection, or at 100-hour inspections for installations with external oil filters. The airframe service manual also listed cleaning the oil suction strainer at every 50-hour interval.
Wreckage and Impact Information
The airplane impacted a field, with all components found within the vicinity of the main wreckage. The initial impact crater was about 4.5 ft deep, and the debris field measured about 225 ft long by 120 ft wide, oriented on a 125° heading. The wreckage was recovered to a salvage facility for examination.
Examination of the airframe revealed that the fuselage was largely fragmented. Flight control continuity was established through multiple overload breaks. The left and right wings were separated at the roots and largely fragmented. The fuel tanks were destroyed by impact forces. The vertical stabilizer remained attached but impact-damaged. The stabilator attach point was separated, and both stabilator sections were fragmented and deformed aft. The rudder remained attached but separated into two sections.
The engine was separated from the airframe and found in the crater. Cylinders Nos. 1–4 were removed and examined; corrosion was noted on the interior of cylinder No. 1, but no other anomalies were observed. Cylinders Nos. 5 and 6 had pistons lodged inside. The crankcase had a hole in the top near the No. 6 cylinder. The top spark plugs from cylinders 3, 4, 5, and 6 showed dark gray, worn, normal electrodes; the rest were impact-damaged. The fuel pump and fuel servo had no anomalies, and the fuel screen was free of debris.
The camshaft was fractured into two sections above the No. 6 crankshaft journal; the aft portion exhibited thermal discoloration. The crankshaft remained in one piece but showed thermal discoloration on the aft section. Bearing surfaces exhibited scoring and smearing. The No. 5 and 6 connecting rods were detached from the crankshaft journals, with the No. 6 journal exhibiting severe thermal discoloration and the No. 5 journal showing extensive thermal discoloration and rotational scoring. The oil sump contained oil, metallic particles, carbon chips, and organic debris. The oil suction screen was obstructed by debris filling about two-thirds to five-eighths of the screen. The debris was retained for analysis. The oil filter, dated March 27, 2020, contained a small amount of carbon chips and metallic debris. The oil pump body exhibited scoring.
Examination of the connecting rod journal bearings revealed extensive damage, including circumferential score marks, heavy wear, galling, and displacement of material, with the worst galling on bearing No. 3. Discoloration due to overheating was present. The NTSB Materials Laboratory examined the camshaft fracture surface, which spiraled circumferentially and had shear lips; the separation was consistent with torsional overstress. The debris from the oil suction screen was sorted: magnetic debris weighed 9.8 grams, non-magnetic weighed 3.1 grams, indicating approximately 75% metallic content.