History of Flight
On February 17, 2014, about 1250 eastern standard time, an experimental, amateur-built Sonex, registration N732SX, collided with terrain shortly after departing the Wellington Aero Club (FD38) in West Palm Beach, Florida. The airline transport pilot/owner was fatally injured, and the airplane was destroyed. Visual meteorological conditions prevailed, and no flight plan was filed for the personal flight conducted under 14 Code of Federal Regulations Part 91. The flight was originating at the time of the accident.
Witnesses stated that during the initial climb, the engine "back-fired" and made a "sputtering" sound. The pilot entered a steep 180-degree turn back towards the airport. The airplane then stalled and entered a nose-down spiral, descending into a canal.
Personnel Information
The pilot, age 58, held an airline transport pilot certificate for airplane multiengine land, airplane single-engine land, rotorcraft-helicopter, and instrument helicopter, issued February 16, 2008, and a first-class airman medical certificate issued February 6, 2012, with no limitations. On his most recent FAA medical certificate application, he reported 13,000 total flight hours. His logbook was not recovered; therefore, total flight experience could not be determined.
Aircraft Information
The single-engine airplane was manufactured in 2007 and powered by an AeroVee series engine equipped with a Sensenich model W54JV544G-AC9751 fixed-pitch propeller. Maintenance logbooks were not located; therefore, maintenance history could not be reconciled.
Meteorological Information
At 1253, recorded weather at Palm Beach International Airport (PBI), about 10 miles east of the accident site, included variable wind 6 knots, 10 statute miles visibility, few clouds at 4,300 feet above ground level. Temperature was 21°C, dew point 11°C, and altimeter setting 30.19 inches of mercury.
Wreckage and Impact Information
The wreckage was located partially submerged in a pond, about 200 yards from the departure end of runway 15. The airplane came to rest on a 109-degree magnetic heading, 3 feet from the pond's edge. It was removed from the pond; all major components were accounted for.
The forward fuselage, firewall, and cockpit were deformed and displaced aft. Both wings remained attached and crushed along the leading edge aft. The vertical stabilizer, elevators, and rudder remained attached. Control continuity was traced from cockpit controls to flight surfaces with no evidence of preimpact mechanical malfunction.
Engine examination revealed separation from the firewall with attached and bent engine mount sections. External impact damage was noted. Ignition lead wires were attached to sparkplugs but separated from coil packs on the firewall; wires showed no breaks or chafing.
Sparkplug examination found the top spark plug on cylinder No. 1 not seated in the cylinder head and finger-tight within the threads. The lower sparkplug was seated and secure. The top sparkplug on cylinder No. 4 was seated and finger-tight. All other sparkplugs were seated securely. Cylinders were checked for blockage; none was found. The crankshaft rotated freely. Valve train continuity and thumb compression were observed on all cylinders.
The throttle body was attached to throttle cables but broken from the manifold; the lever actuated when throttle was manipulated. The air filter was crushed and impact-damaged. The fuel line was connected to the throttle body but separated from the electric fuel pump. Accessory plate was impact-damaged. Oil cooler crushed; oil lines remained attached but broken from pump; oil was present in lines and sump.
The propeller remained attached to hub and crankshaft. One wooden blade was splintered; the other had span-wise cracks across the forward face.
Additional Information
According to a friend of the pilot, he assisted the pilot during an oil change two days prior. The friend stated the pilot attempted to change sparkplugs and cross-threaded the upper sparkplug on cylinder No. 1, then attempted to helicoil the cylinder thread. The friend inspected the sparkplug and noted that the sparkplug and helicoil could be pulled out of the cylinder head. The pilot continued working on the engine, but the friend did not know if the pilot repaired the cylinder head or flew the airplane after repair before the accident flight. During engine examination, a helicoil was not observed in the No. 1 sparkplug cylinder head threads.
The airplane was equipped with a Stratomaster Enigma EFIS capable of recording flight data, GPS positions, and engine monitor data to an SD card. The SD card was recovered and sent to the NTSB Vehicle Recorder Division. Data review revealed all engine parameters were normal during initial climb. Further review showed cylinder No. 1 head and exhaust gas temperature dropped approximately 100 degrees, followed by a loss in rpm and airspeed. GPS data then showed the airplane making a banking left turn as described by witnesses.
Medical and Pathological Information
An autopsy was performed on the pilot on February 18, 2014, by the Office of the District Medical Examiner, District 15 State of Florida. Toxicological testing was performed by the FAA Bioaeronautical Science Research Laboratory. Review of the toxicology report revealed no carbon monoxide detected in cavity blood; no ethanol in vitreous. The following drugs were detected in blood cavity: 0.091 ug/ml Citalopram and 0.04 ug/ml N-Desmethylcitalopram. Citalopram and Desmethylcitalopram are antidepressant drugs used to treat depression.