Accident Flight
On November 29, 2018, at about 1421 eastern standard time, a Piper PA-30 (Twin Comanche) airplane, registration N7751Y, impacted terrain shortly after takeoff from Marion Municipal Airport in Marion, Indiana. The pilot, who held an airline transport pilot certificate and an airframe and powerplant mechanic rating, sustained fatal injuries. The airplane was destroyed. The flight was conducted under Title 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed, and no flight plan was filed for the local flight.
According to a sheriff's deputy, fixed-based operator employees observed the pilot performing ground engine runs outside his hangar on the day before the accident. Family members reported that the pilot had been troubleshooting an unspecified fuel system problem with the left engine. A family member described the accident flight as a "test flight."
Witnesses reported that after departure, the airplane climbed to about 500 ft above ground level and began a left turn. During the turn, the airplane "nose-dived" in a downward spiral. It then impacted terrain, and a post-impact fire ensued.
Aircraft Information
The pilot's logbook was not located during the investigation. An estimate of the pilot's flight time was determined from his most recent airman medical application. The airplane was registered to the pilot on December 17, 2008. During a post-accident examination of the pilot's hangar, an invoice dated November 16, 2018, was found for the purchase of left and right fuel selector valves and miscellaneous installation hardware. An empty shipping box for the valves was also found. Additionally, a fuel selector access plate, a fuel valve protector cover, and fuel valve control handles for the airplane were located in the hangar. These components would have been removed during the replacement of the fuel selector valves and reinstalled after the installation.
The Piper Twin Comanche Service Manual describes the fuel system as containing two independent units, each supplying its own engine, connected only by a crossfeed for emergency use. The fuel selector valves are operated by controls located in a panel between the pilot seats. The Owner's Handbook provides procedures for emergency single-engine operation using the crossfeed and describes the propellers as constant-speed, controllable, full-feathering units, with feathering accomplished by moving the propeller control levers fully aft.
Wreckage Examination
The airplane came to rest upright in a soft, wet field about 1/4 mile south of the departure runway. The fuselage, empennage, and inboard sections of both wings were consumed by post-impact fire. The instrument panel, instruments, and engine controls were destroyed. The right front seat was not installed and was found in the pilot's hangar. Flight control continuity could not be determined due to impact and thermal damage, but no mechanical anomalies were noted that would have precluded normal operations.
Examination of the fuel selector positions revealed the left fuel selector arm in the cross-feed position and the right fuel selector arm in the right main fuel cell position. Thermal damage prevented movement of the selectors. The left auxiliary fuel line and fitting were not located at the time of the examination, but on-scene photographs showed the line and fitting partially in place with only partial thread engagement. Magnified examination of the selector valve threads showed no damage.
Both engines exhibited continuity to all pistons and accessory gearboxes, with thumb compression noted on all cylinders. Magnetos and accessories were thermally damaged, precluding functional testing.
Medical Findings
The Northeast Indiana Forensic Center performed an autopsy of the pilot, determining the cause of death as multiple blunt force injuries. Toxicology testing by the FAA Forensic Sciences Laboratory identified doxylamine (0.153 ug/mL, ug/g) in the pilot's liver specimens but not in his aortic blood specimens. Tests were negative for carbon monoxide and ethanol.