CEN19FA248

The pilots departed on a local flight in the multiengine airplane in visual meteorological conditions. Radar and GPS data showed the airplane maneuvering around the area of the departure airport at an altitude about 2,000 to 1,800 ft above ground level before it turned toward the airport and entered a descent that continued until ground contact. During the descent, the airplane’s speed slowed below its published stall speed. Examination of the airframe and engines did not reveal any anomalies that would have precluded normal operation of the airplane. A review of weather information found an area of cumuliform clouds and dissipating precipitation near the accident site. Although no AIRMETs or SIGMET advisories were valid for the area around the time of the accident, scattered thunderstorm activity was forecast for the area of the accident site around the accident time. During the dissipating stage, rain showers and thunderstorms are dominated by downdrafts and outflow boundaries. Although nearby surface observations did not record any gusty wind around the accident time, it is possible that the airplane encountered an area of localized outflow or turbulence that may have contributed to the accident.

A review of FAA records indicated that no major repairs or modifications of the airplane occurred after March 2003. Maintenance logbooks recorded that the last annual inspection was completed on October 3, 2018. No other work was recorded in any of the logbooks after that date. On August 4, 2019, at 1650 central daylight time, a Cessna 310I airplane, N310QA, was substantially damaged when it was involved in an accident near De Queen, Arkansas. The commercial pilot was seriously injured, and the private pilot was fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. A review of Federal Aviation Administration (FAA) radar data revealed a radar target correlated to the accident airplane that departed from J Lynn Helms Sevier County Airport (DEQ) about 1603. The target continued southeast for about 6 miles before it turned left and proceeded northeast past Dierks, Arkansas. At 1614, the airplane’s altitude-reporting transponder indicated that the airplane was 2,500 ft mean sea level (msl) at a speed of 143 knots (kts). At 1621, the airplane made a descending 270° clockwise turn. It descended as low as 1,100 ft msl before it climbed to about 2,200 ft msl and flew to the northwest, followed by a turn southwest. The airplane then entered a descending turn and radar track data were lost at 1648. A review of data retrieved from an onboard GPS unit indicated that the airplane reached takeoff speed and climbed away from DEQ at 1603, consistent with FAA radar data. During the recorded flight, the airspeed reached a maximum of 173 knots as it maneuvered in the area around De Queen, Arkansas. At 1646, the airplane began a gradual descent from 2,000 ft msl as it turned south. Rather than continue a left turn toward DEQ, the airplane made a descending, right 270° turn. During this turn, the airspeed gradually decreased as the airplane continued its descent. The airplane continued toward the airport for about 1.7 miles; the recorded airspeed at 1650:31 was 73 kts and at 1650:34, the airspeed was 53 knots. The airplane’s published stall speed with the landing gear and flaps retracted and 0° of bank was 83 kts. The FAA Forensic Sciences Laboratory performed toxicology testing on the private pilot. Testing was positive for diphenhydramine, tamsulosin, sildenafil, and metoprolol. On his most recent application for an FAA medical certificate, the pilot reported no illnesses and no use of medications. Diphenhydramine is a sedating antihistamine and is available over the counter in many products used to treat colds, allergies, and insomnia. Diphenhydramine carries a warning that use of the medication may impair mental and physical ability to perform potentially hazardous tasks, including driving or operating heavy machinery. FAA provides guidance on wait times before flying after using this medication; post-dose observation time is 60 hours, and the medication is not for daily use. Weather observations from DEQindicated visual flight rules conditions with a variable surface wind of 5 kts or less. Upper air soundings indicated an unstable environment with conditions conducive to the development of multicell rain showers or thunderstorms. Given the environment, if rain showers or thunderstorms formed, the sounding indicated that the strongest wind speeds possible at the surface, due to a microburst, outflow boundary, or gust front, could reach 55 kts. Satellite imagery captured a line of cumuliform clouds moving north to south with cloud cover above the accident site at the accident time. Doppler radar recorded an area of dissipating precipitation about 1-2 miles north of the accident site. Graphical Forecasts for Aviation products issued prior to and valid for the accident flight indicated the visual flight rules conditions with scattered (30% to 50%) thunderstorms and a surface wind from the north at 5 kts. There were no active AIRMET or SIGMET advisories valid for the area of the accident site around the time of the accident. There was no record of either of the pilots receiving a formal weather briefing before the flight, and what information they accessed or received was not determined. FAA Advisory Circular AC00-6B, “Aviation Weather,” states that downbursts and microbursts are associated with rain showers and more frequently with thunderstorm activity. Downbursts create many hazards for aviation and often cause damaging wind at the surface. The pilot seated in the left seat held a commercial pilot certificate. On his most recent application for an FAA airman medical certificate, he reported 3,464 total hours of flight experience. He sustained serious injuries in the accident, and his spouse reported that he did not recall the accident. The pilot seated in the right seat held a private pilot certificate. He reported 6,000 total hours flight experience on his most recent medical certificate application. The airplane impacted a pasture area less than a mile south of DEQ. The initial impact point was consistent with the right wing impacting the ground, followed by the fuselage. A small debris field followed a 106° heading for about 145 ft. The main wreckage comprised the fuselage, both wings, both engines, the right propeller, empennage, and tail, and came to rest on a 290° heading. A postimpact fire burned a portion of the field and some of the airplane's fuel system. The airplane’s landing gear and flaps were both found in the retracted position. An examination of the airframe did not reveal any pre-impact anomalies. The engines were removed and disassembled for examination. No anomalies were detected that would have precluded normal engine operation.