Cessna 340 N247AT Collision with Terrain Near Bartow, Florida

Accident Overview and Flight Details On December 24, 2017, at 0717 eastern standard time, a Cessna 340 airplane, N247AT, impacted terrain shortly after departing from Bartow Municipal Airport (BOW) in Bartow, Florida. The private pilot and four passengers were fatally injured, and the aircraft was destroyed. The airplane was registered to Aviation Transportation LLC and was operating under Title 14 Code of Federal Regulations Part 91 as a personal flight. The flight originated at BOW with a planned destination of Key West International Airport (EYW). Instrument meteorological conditions prevailed, and an instrument flight rules (IFR) flight plan was filed. The pilot received an IFR clearance from the Tampa air traffic control tower, while the BOW tower was closed. ## Pre-Flight and Takeoff Sequence Two fixed base operator (FBO) employees reported that the pilot requested the aircraft be towed from the hangar to the ramp due to reduced visibility and dense fog. Around 0645, the five occupants boarded, and the FBO employees towed the aircraft to the ramp. The pilot started the engines, and the aircraft slowly taxied toward the end of runway 9L. Visibility was limited to about 400 feet. The pilot contacted Tampa Approach at 0710 for an IFR clearance. FBO employees heard an engine run-up and, around 0715, heard the aircraft take off, though it was not visible due to the fog. The engines were described as sounding strong and operating at full power. After two tire chirps on the runway, the sound was consistent with a climb, followed by an explosion on the east side of the airport. The FBO employees found the aircraft on fire. A 46-second video recorded by an FBO employee captured the takeoff roll and two distinct chirps at 26 and 28 seconds. A helicopter pilot based at BOW also recorded the taxi and heard the takeoff about 12 minutes later, followed by a pop similar to an engine backfire and an explosion near the end of runway 9L. The helicopter pilot estimated the runway visual range at 600 to 800 feet. ## Personnel and Aircraft Information The pilot's logbooks were not located, so instrument currency or proficiency could not be determined. A mechanic who maintained the aircraft stated that the pilot always flew with his feet flat on the floor and not on the rudder pedals, and that the pilot never flew dangerously or recklessly. The pilot's personal assistant stated that the pilot always flew the aircraft a couple of days before a flight with passengers and was described by others as a good and diligent pilot. An acquaintance and former flight instructor recounted that the pilot mentioned an in-flight engine failure in the accident aircraft and continued to his destination rather than making a precautionary landing. The acquaintance also noted that the pilot believed they were legally allowed to fly under Part 91 despite poor weather conditions. A local airplane mechanic stated that he was not a safe pilot and took unnecessary risks. The mechanic who maintained the aircraft reported that two days before the accident, he moved the co-pilot seat aft and adjusted the rear seats forward at the pilot's request. The aircraft had a known autopilot issue where engaging the autopilot on the ground would command the elevator trim full nose-down due to the autopilot's gyros not being level. The pilot was aware of this issue. The airplane logbooks did not reveal any past maintenance discrepancies or write-ups related to the autopilot or elevator trim. On December 22, 2017, an FBO employee filled the airplane's tip tanks and auxiliary tanks with 100LL fuel, and the pilot flew the aircraft for about 30 minutes before it was towed back to the hangar. A review of the engine maintenance logbooks revealed entries for annual inspections that included oil changes and oil filter replacements on January 2, 2017, at 1,582.9 hours, December 20, 2015, at 1,558.4 hours, and November 17, 2014, at 1,543 hours. However, the oil filter found on the left engine at the accident site was marked with 1,543 hours and dated January 6, 2014. The mechanic stated that the oil was not actually changed during the two previous inspections as noted in the logbooks and that the entries were not accurate. The mechanic planned to change the oil and replace the filters during the next annual inspection, due in January 2018. The most recent IFR certification for the transponder and pitot static system was completed on June 20, 2014, and the system must be inspected and certified every 24 calendar months to fly in IFR conditions. ## Meteorological and Airport Conditions The automated weather observation station at BOW reported consistent weather conditions from 0635 to 0715, including visibility less than 1/4 mile, fog, an overcast cloud layer at 300 feet, a temperature of 56°F, and an altimeter setting of 30.18 inches of mercury. An area forecast discussion identified widespread shallow fog, and a dense fog advisory was in effect for Polk County, Florida. A center weather advisory advised of ceilings below 500 feet above ground level and visibilities below 1 mile in fog and mist, and an AIRMET for IFR conditions was in effect. There was no evidence that the pilot obtained a preflight weather briefing from a recorded source. ## Wreckage and Impact Information The accident site was located on airport property about 190 yards east-northeast of the departure end of runway 9L and 10 feet south of taxiway delta. The debris path was about 230 feet long and oriented northeast. The main wreckage came to rest upright and oriented southeast about 30 feet from the initial impact craters. The fuselage was mostly consumed by fire, and the empennage remained mostly intact with significant thermal damage. Both engines separated from the aircraft and came to rest near the main wreckage. The nose landing gear was found about 200 feet northeast of the main wreckage. The flight controls exhibited impact and thermal damage but did not reveal any preimpact anomalies. The wing flap position could not be determined due to extensive damage. The elevator trim tab was found beyond its full up limit, and the elevator trim cable exhibited tension overload separations near the actuator. The elevator trim actuator was found at 2 ¼ inches, beyond the full length of travel (1.9 inches). The landing gear actuator and the left and right main landing gear were all retracted. Two attitude indicator gyros and one directional gyro were disassembled and examined, and all three exhibited rotational scoring inside the housings and along the circumference of the gyros. An electric turn-and-bank indicator gyro also exhibited rotational scoring. The two vacuum pumps were separated from the engines and sustained significant impact damage. The left engine was separated from the airframe, and the crankshaft was completely fractured at the nose oil seal. The fracture surface displayed tearing, shear lips, and discoloration consistent with an overstress separation on impact. The top sparkplugs displayed a normal worn appearance, and the bottom sparkplugs were examined with no anomalies noted. Residual fuel poured from the pressure regulator when the return line was removed. The fuel manifold valve remained secured to the top of the engine, and the fuel lines remained attached to the housing. The fuel manifold screen was clear of contaminants, and residual fuel was observed in the housing. The No. 2 intake inner valve spring was fractured. Residual oil was observed in each rocker cover, and the No. 3 exhaust valve displayed two areas of green discoloration. The right engine was also separated from the airframe, and the crankshaft was fractured at the nose oil seal. The engine sustained thermal damage. The left magneto was separated from the engine, and the ignition leads were separated from the harness cap. The right magneto remained in place and did not rotate with manual manipulation. The left magneto harness cap was removed and replaced with the right ignition harness cap from the left engine, and rotation of the drive shaft resulted in a spark from each lead in firing order. The right magneto was removed, and the thermally damaged leads were cut near the harness cap. The magneto produced a spark from each of its leads in firing order when the drive shaft was manually rotated. The top sparkplugs on the right engine displayed a normal worn condition, and the bottom sparkplugs were examined with no preimpact anomalies noted. The engine-driven fuel pump was separated from the engine, and the mounting flange and drive coupling were displaced to one side. The fuel manifold valve screen was free of obstructions, and residual fuel was observed in the housing. The cylinders remained attached to the crankcase with no external signs of operational distress, and all valve springs remained intact. The pistons, valves, and valve seats were unremarkable. ## Additional Information and Medical Findings According to FAA Safety Team literature, pilots flying under both instrument and visual flight rules are subject to spatial disorientation and optical illusions that may cause a loss of aircraft control. When visibility is restricted, the body's supporting senses can conflict with what is seen, making it difficult for a pilot to tell which way is up. These phenomena are contributed to by visual, vestibular, and proprioceptive sensory stimuli, which can vary in magnitude, direction, and frequency, resulting in a sensory mismatch that can produce illusions and lead to spatial disorientation. The Office of the District Medical Examiner, 10th Judicial Circuit of Florida, Winter Haven, Florida, completed an autopsy on the pilot, which attributed the cause of death to blunt impact. The FAA's Bioaeronautical Sciences Research Laboratory, Oklahoma City, Oklahoma, conducted toxicology testing, which revealed 20 mg/dL of ethanol in muscle, ibuprofen in the muscle, and no ethanol detected in the kidney. The toxicology samples exhibited putrefaction. Ibuprofen is in a class of medications called non-steroidal anti-inflammatory drugs and are not considered impairing. After absorption, ethanol is uniformly distributed throughout all tissues and body fluids; therefore, the finding in one tissue but not another is most consistent with post-mortem production. ## Weight and Balance The airplane's maximum gross takeoff weight was 6,390 lbs. The weight at the time of the accident takeoff was about 6,495 lbs, about 105 lbs over the maximum takeoff weight. Due to the excessive weight, the airplane was outside of its center of gravity moment envelope.