ERA18LA083

The private pilot had been having engine issues on his single-engine, experimental, amateur-built airplane and the purpose of the flight was to test the engine. A witness heard the pilot start the airplane's engine, taxi to the runway, and depart without conducting an engine run-up. When the airplane was about halfway down the 4,000-ft-long runway, he heard the engine lose power. The witness looked up and saw the airplane about 100 ft above the runway; it then entered an "aggressive bank" to the left and subsequently stalled and descended "straight down." The airplane came to rest upright in heavily wooded and swampy terrain about 250 yards north of the airport. The airplane was not recovered from the swamp or examined, and the reason for the loss of engine power was not determined. The pilot succumbed to his injuries after being transported to the hospital. The pilot's admission blood was submitted by the medical examiner for toxicology and the results were negative for all items tested. Postmortem toxicology identified several medications that were likely given as part of postaccident medical treatment, as well as sildenafil, diphenhydramine, and zolpidem. Though diphenhydramine and zolpidem are impairing drugs, it is unlikely that effects from these medications contributed to the accident circumstances. Given the witness statement, it is likely that the pilot exceeded the airplane's critical angle of attack during the attempted return to the runway following the loss of engine power, which resulted in an aerodynamic stall and impact with terrain.

The witness stated that the pilot had purchased the airplane about 2 years before the accident when it was almost completely built. The pilot finished building the airplane, which was equipped with a Volkswagen engine. The witness said that the pilot had experienced "constant" problems with the engine, and the current engine was the second one he had installed on the airplane. The witness stated that, at one point, the wrist pins had failed. The pilot was known to take apart the engine, fix something, and reassemble it, only to have another problem. The witness thought that the pilot had recently replaced some gaskets and that he wanted to see how the engine was working. The witness stated that the pilot was not known for "writing things down" regarding maintenance on the airplane or engine. A review of the engine logbook revealed that the pilot had removed the engine twice in 2016 and rebuilt it. After the second rebuild, the pilot zero-timed the engine and conducted a successful test flight. The last entry in the engine logbook was on August 10, 2017, at a total time of 95.23 hours and 21.23 hours-in-service. The logbook indicated that the oil was changed/added, and the tappets were adjusted. On February 5, 2018, at 1125 eastern standard time, an experimental, amateur-built Sonex Trainer airplane, N543SX, sustained substantial damage when it collided with terrain following a loss of engine power after takeoff from Carrabelle-Thompson Airport (X13), Carrabelle, Florida. The private pilot, who was also the owner and builder of the airplane, was fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. Visual meteorological conditions prevailed near the airport and no flight plan was filed for the local flight, which was originating at the time of the accident. A witness, who was also a friend of the pilot, stated that the pilot had been having some mechanical issues with the engine and that the purpose of the flight was to test the engine. On the morning of the accident, the witness heard the pilot start the airplane's engine and taxi to runway 5. He did not hear the pilot perform any engine run-up or test run on the ground before departure, but the engine sounded "normal." The airplane then departed. When it was about halfway down the 4,000-ft-long runway, the witness heard the engine lose power. He stated that there was no sputter or sound of a rough-running engine, "the rpm just decelerated." The witness looked up and saw the airplane about 100 ft above the runway. Instead of landing on the remaining runway, the pilot made an "aggressive bank" to the left and the airplane stalled and descended "straight down" toward the ground. The airplane came to rest upright in heavily wooded, swampy terrain about 250 yards north of the airport. There was no postimpact fire. Both wings and the fuselage sustained substantial damage. The airplane was not recovered or examined. The pilot was taken viahelicopter to the hospital where he succumbed to his injuries. An autopsy was conducted by the Office of the Medical Examiner, Tallahassee, Florida, and the cause of death was "multiple blunt force trauma." The pilot's admission blood was submitted by the medical examiner for toxicology and the results were negative for all items tested. Toxicology testing performed at the FAA Forensic Sciences Laboratory on postmortem specimens identified ketamine and its metabolite, norketamine; midazolam and its metabolite, hydroxymidazolam; etomidate; and fentanyl in cavity blood. In addition, sildenafil and its metabolite, desmethylsildenafil, were found in cavity blood, diphenhydramine was found in cavity blood (0.265 ug/ml) and liver, and zolpidem was found in kidney but not blood. According to the postaccident treatment records, the pilot was intubated during transport to the hospital. The hospital records did not contain a list of medications given to enable that procedure, but the most common choices would have been ketamine, etomidate, and fentanyl. The records reflect the pilot was given midazolam during his initial resuscitation in the hospital. Sildenafil (commonly known as Viagra) is used to treat erectile dysfunction and is not considered impairing. Diphenhydramine, commonly marketed as Benadryl, is a sedating antihistamine, used to treat allergy symptoms and as a sleep aid. It can be impairing. Zolpidem is a short-acting sleep aid often marketed with the name Ambien, available by prescription as a Schedule IV controlled substance. The 1053 recorded weather at Apalachicola Regional Airport-Cleve Randolph Field (AAF), Apalachicola, Florida, located about 18 miles west of the accident site, included wind from 050° at 9 knots, clear skies, temperature 15°C, dew point 8°C, and an altimeter setting of 30.23 inches Hg. The pilot held a private pilot certificate with a rating for airplane single-engine land and an airframe and powerplant certificate. His most recent Federal Aviation Administration (FAA) third-class medical certificate was issued on May 3, 2016, at which time he reported 571 total hours of flight experience. The pilot's logbook was not available for review. The witness described the pilot as a "known risk taker."