History of Flight
On August 15, 2014, about 1535 central daylight time, a Cessna 414 multi-engine airplane, registration N127BC, was destroyed after impacting terrain near Bowie Municipal Airport (0F2), Bowie, Texas. The pilot and passenger sustained fatal injuries. The airplane was operated by the pilot under 14 CFR Part 91 as a personal flight. Day visual meteorological conditions prevailed, and no flight plan was filed. The flight departed La Porte Municipal Airport (T41), La Porte, Texas, at 1344, destined for 0F2.
A witness observed the airplane at about 500 feet above ground level on a left base leg for a south landing. The witness reported that the airplane suddenly pointed straight down, began spinning, and made three complete rotations before impacting the ground. Evidence at the scene indicated the airplane impacted in a nose-down attitude, came to rest upright, and was mostly consumed by an immediate post-impact fire.
Personnel Information
The 51-year-old pilot held an FAA commercial pilot certificate with ratings for airplane single-engine land, multi-engine land, and instrument airplane. He also held a third-class medical certificate issued on March 5, 2014, with a restriction to wear corrective lenses. Personal logbooks were unavailable; however, partial entries and statements indicated an estimated total flight experience of about 1,200 hours, including approximately 15 hours in Cessna 414 airplanes in the previous 90 days. The pilot completed initial and recurrent training in a Cessna 414 on July 30, 2014, meeting biennial flight review requirements.
Aircraft Information
The accident airplane, serial number 414-0519, was a 1974 low-wing, retractable landing gear, pressurized multi-engine aircraft. It was powered by two 335-horsepower Continental Motors TSIO-520 series turbocharged engines, each driving a three-bladed McCauley propeller. The left engine had been converted to a TSIO-520-N in 1997, and the right engine to a TSIO-520-NB. The airplane was equipped with Micro Aerodynamics vortex generators installed under an STC.
Complete maintenance logbooks were not located. Partial entries showed the airplane had a satisfactory annual inspection on June 17, 2014, with a recorded total time of 4,256.4 hours. At that time, the left engine had 4,300.2 total hours (1,139.4 since overhaul), and the right engine had 5,265.8 total hours (783.0 since overhaul). FAA records indicated the airplane was initially registered to the pilot on July 14, 2014.
Meteorological Information
At 1535, the AWOS at 0F2 reported wind from 150 degrees at 9 knots gusting to 14 knots, visibility 10 miles, clear sky, temperature 35°C, dew point 17°C, and altimeter 29.92 inHg. The variable wind produced a tailwind on the left base leg and a left crosswind component of about 14 knots during landing. A witness operating a pipeline patrol airplane at about 2,000 feet agl reported severe to extreme turbulence with frequent strong low-level thermals causing sudden downdrafts. He described an experience where his airplane "completely stopped flying and just fell straight down."
A National Weather Service upper air sounding indicated a high estimated cloud base near 9,000 feet agl with strong thermals and a super-adiabatic lapse rate in the lowest 1,000 feet, enhancing thermal development. The wind profile showed strongest winds at 2,000 feet msl (15 knots from 140 degrees), with no strong vertical wind shears below 18,000 feet.
Wreckage and Impact Information
The wreckage was located on a rural flat grassy pasture about 1 mile north of 0F2, at an estimated elevation of 1,105 feet msl. A post-impact fire consumed major portions of the fuselage and wings. Impact evidence showed the airplane struck the ground in a partially nose-down attitude (about 15 degrees), coming to rest upright oriented on a magnetic heading of 135 degrees. Dirt ejecta was observed on a debris direction of about 150 degrees.
Emergency responders found the pilot in the left front seat and the passenger in the rear passenger cabin area, though the specific seat location could not be determined. Thermal damage prevented assessment of safety belt usage.
Both wings and all flight control surfaces remained attached. The flaps were extended to about 35 degrees. The landing gear was extended. Flight control continuity was mostly confirmed. Both engines remained attached, and both propellers showed signs of low rotational energy at impact. The throttle controls were found in the closed position.
Examination of the wreckage revealed no evidence of preimpact mechanical malfunctions or failures that would have precluded normal operation.
Additional Information
According to the Cessna 414 Pilot's Operating Handbook, the clean configuration stall speed at zero bank angle was 83 knots IAS, and the landing configuration stall speed at zero bank angle was 71 knots IAS. At a 40-degree bank, the landing configuration stall speed was 81 knots IAS.
A Garmin GPSmap 696 handheld GPS recovered from the wreckage provided data for the accident flight. The data showed that as the airplane neared 0F2, it began a descent at 1534:16 and turned left to enter a left base for runway 17. Groundspeed decreased from 132 knots at 2,249 feet msl to 80 knots at the final recorded altitude of 1,528 feet msl at 1535:26.
Medical and Pathological Information
An autopsy of the pilot revealed significant atherosclerotic disease (60 to 80 percent) and evidence of an acute, premortem, non-occlusive thrombosis of the left anterior descending coronary artery. The medical examiner concluded that the pilot likely suffered an acute cardiac event while piloting the aircraft. Toxicology tests detected no ethanol or listed drugs in the pilot's blood.