N8014TBeech A36 · 1990

On June 8, 2019, at 0914 eastern daylight time, a Beech A36, N8014T, was destroyed when it was involved in an accident near Mattituck, New York. The commercial pilot and passenger were fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.

The departure airport tower controller approved a radio frequency and transponder code change, which terminated communications with the airplane, as the pilot had not requested flight following services.

About 0911:52, at 3,325 ft mean sea level (msl) and 107 knots (kts) groundspeed, about 1 mile north of the shoreline near Northville, New York, the airplane's track turned right from its on-course heading of 060°, and the airplane began a descent. The airplane turned to about 120° and at 0912:41, it crossed the shoreline at Suffolk, New York, at 2,175 ft msl and 88 kts. About that time, the pilot contacted air traffic control and announced that the airplane had experienced "engine failure" and that he would perform a forced landing in a field. Figure 1 shows the airplane’s radar track and descent over open fields.

Figure 1. Map showing the airplane's radar track.

The controller assigned the airplane a discrete transponder code and requested information from the pilot. During the exchange, the pilot again announced his intention to "land in a field." About 1 minute later, the controller transmitted that radar contact was lost, and there were no further communications from the airplane.

The radar track showed that the airplane turned eastbound approximately over New York State Route 48. The airplane continued to descend over SR48 before it entered a tight left turn and reversed course to the west around a commercial farm, where radar contact was lost. The last radar target was depicted at 25 ft msl and 88 knots about 200 ft east of the accident site.

Witnesses near the accident site described the airplane as flying "low" and one witness asked another if the airplane "was a crop-duster." One witness stated he heard the engine, and another said he did not.

Surveillance video depicted the airplane at low altitude in a steep left bank as it turned from a northerly to a westerly heading, descending out of view behind trees before it impacted the ground. A dark plume of smoke appeared immediately after.

According to the mechanic who worked on the airplane, the pilot was concerned that the oil temperature was higher than usual, and the oil pressure was low. The mechanic changed the oil and oil filter and ran the engine. Afterwards, he removed and opened the oil filter and found metal debris. After consulting the pilot, he sent an oil sample for analysis and told him he was not comfortable working on the airplane and suggested replacing the engine.

The mechanic stated that he stressed to the pilot on numerous occasions that he felt the visual inspections and results of oil analysis indicated a rapid degradation of the condition of the engine and the potential for immediate catastrophic loss. When asked about specifics and frequency of this conversation, the mechanic noted multiple conversations in the preceding weeks and days before the accident.

According to the mechanic who worked on the airplane, the pilot was concerned that the oil temperature was higher than usual, and the oil pressure was low. The mechanic changed the oil and oil filter and ran the engine. Afterwards, he removed and opened the oil filter and found metal debris. After consulting the pilot, he sent an oil sample for analysis and told him he was not comfortable working on the airplane and suggested replacing the engine.

The mechanic stated that he stressed to the pilot on numerous occasions that he felt the visual inspections and results of oil analysis indicated a rapid degradation of the condition of the engine and the potential for immediate catastrophic loss. When asked about specifics and frequency of this conversation, the mechanic noted multiple conversations in the preceding weeks and days before the accident.

The airplane came to rest inverted on a commercial farm. The wreckage path was oriented on a magnetic heading of 270° and was 105 ft in length.

All major components of the airplane were accounted for at the scene. The cockpit, cabin, empennage, and both wings were consumed by post-crash fire. The vertical stabilizer and left horizontal stabilizer were impact damaged but intact. The right horizontal stabilizer was separated by impact. Flight control continuity was confirmed from the cockpit area to all flight control surfaces. The landing gear was in the retracted position. The flaps were consistent with the retracted position; however, the flap actuator was destroyed by fire and the actual pre-accident position could not be confirmed.

The propeller was separated from the crankshaft and all three propeller blades were secure in the hub. Each blade exhibited similar aft bending and light chordwise and spanwise scratching. Some leading edge polishing was also observed.

The engine was rotated by hand through an accessory drive pad and powertrain continuity was confirmed through the valve train to the accessory section. Thumb compression was confirmed on all but cylinder Nos. 2 and 6. Borescope examination of those cylinders revealed debris around the valves consistent with soot and ash, which prevented full seating of the valves.

Examination of the spark plugs revealed normal wear; the electrodes were light grey in color. The magnetos were removed and rotated. The impulse couplings engaged, but no spark was produced. Disassembly of each magneto revealed that the internal components were damaged (melted) by heat exposure. The fuel manifold was removed and disassembled. Examination revealed trace amounts of fuel. The internal spring, diaphragm, and screen were all intact and absent of water and debris.

A detailed examination of the engine revealed that the No. 1 main aft bearing had shifted. The crankcase halves exhibited fretting and lock slot elongation. The rear of the crankshaft was no longer connected to the main bearing and there was extensive internal and thermal damage. The severely burned oil filter was cut open and remaining filter media was spread open, big metal flakes of ferrous and non-ferrous materials were consistent with internal catastrophic failure. The aft main bearing was heavily damaged with spun a bearing in the rear main journal.

The engine-driven fuel pump was removed and rotated with a drill. Air was drawn into the intake port and exited the output ports when the pump was actuated. The fuel pump drive coupling was sent to the NTSB Materials Laboratory for examination. There were multiple rachet marks and striations on the fracture surfaces consistent with multiple initiation fatigue cracking and fatigue fracture. Microvoid coalescence was also present on both fracture surfaces, consistent with overstress separation.

Toxicology testing performed at the FAA Forensic Sciences Laboratory was negative for carbon monoxide, ethanol, and tested-for drugs.