ERA22FA397

The helicopter pilot was flying a cross-country flight in thunderstorms. The former owner of the helicopter, its new owner, stated they were worried about the weather and tried to talk the pilot into waiting 1 day until the weather improved, however, the pilot did not want to wait and subsequently departed for his home airport. Postaccident examination revealed no anomalies with the engine or airframe that would have precluded normal operation. There was no record of the pilot obtaining a weather briefing and rising terrain led up to the area of the accident. The observations surrounding the time of the accident from the closest official weather station indicated visual flight rules to instrument flight rules conditions, with reflectivity data indicating that thunderstorms were present along the route and at the accident site at the time of the accident. Accordingly, the flight likely encountered reduced visibility and heavy rain while in thunderstorms as a result of the pilot’s decision to fly in thunderstorm conditions. Had the pilot obtained a weather briefing he likely would have had increased his awareness of the severity of the weather conditions along his route of flight and may have elected to delay the flight further until conditions improved.

HISTORY OF FLIGHT On September 3, 2022, about 1740 central daylight time, an experimental, amateur-built RotorWay JetExec helicopter, N162NH, was destroyed when it was involved in an accident near Arthur, Kentucky. The pilot was fatally injured. The helicopter was operated as a Title 14 Code of Federal Regulations (CFR) Part 91 personal flight. The accident pilot was a friend of the helicopter owner, who had purchased the helicopter about 1 week before the accident and asked his friend to fly the helicopter from Missouri to Tennessee. The owner of the helicopter stated that he was “worried” about the weather on the day of the accident and tried to talk the pilot into waiting to fly the helicopter to Tennessee until the weather improved. The pilot did not want to wait, and he and his wife departed on the cross country flight about 1030. According to the seller and previous owner, about 30 minutes later, the helicopter returned to the departure airport so that the pilot could drop off his wife. The seller stated that he tried to talk the pilot out of leaving that day because that flight would be long and rain was occurring along the route. The pilot waited “a couple of hours for the weather to improve” and then departed again. On September 5, the helicopter wreckage was located in heavily wooded, steep terrain in Mammoth Cave National State Park. Review of automatic dependent surveillance-broadcast (ADS-B) data revealed that data associated with the helicopter’s flight track ended about 40 nautical miles prior to the accident location. Additionally, the terrain became generally higher leading up to the area of the accident site. METEOROLOGICAL INFORMATION A search of archived information indicated that the accident pilot did not request weather information from Leidos Flight Service or ForeFlight. The accident pilot updated various potential flight paths and viewed airport information via ForeFlight through 1326 on the day of the accident. The available evidence did not show what, if any, weather information the accident pilot may have viewed before or during the accident flight. A convective SIGMET advisory was valid for the accident site at the accident time. The advisory, which was issued at 1655, warned of an area of thunderstorms with cloud tops above flight level 450 with the convective area moving from 210° at 15 knots. In addition, a convective SIGMET was issued at 1555 that was valid for the accident area (Figure 1). Figure 1. Aviation Weather Center graphic valid at 1700 CDT with valid convective SIGMETs, AIRMETs, and PIREPS with the accident location marked. The observations surrounding the time of the accident from the closest official weather station indicated visual flight rules to instrument flight rules conditions with moderate-to-heavy rain and thunderstorms. Radar returns (Figure 2) showed the precipitation in the vicinity of the accident area, moving from southwest to northeast. 318 lightning flashes were reported within 50miles of the accident site within 20 minutes before or after the time of the accident (Figure 3). Figure 2. National Reflectivity Mosaic for 1740 CDT with the accident site marked with the black circle. Figure 3. Base reflectivity scan initiated at 1739:55 CDT with the accident site marked with the black circle. WRECKAGE AND IMPACT INFORMATION The helicopter came to rest on its left side on a magnetic heading of about 045°. The cabin, instrument panel, seats, and engine compartment had fractured into several pieces. The tailboom remained attached to the fuselage but was heavily damaged from impact forces. The tail rotor was wedged between two trees, and both tail rotor blades had separated and were located near the front of the helicopter. The engine was separated from the gearbox due to impact. The engine exhibited evidence of tortional twisting. The engine and main rotor gearbox rotated freely. A borescope examination of the combustion and turbine blades found no anomalies. MEDICAL AND PATHOLOGICAL INFORMATION The Office of the State Medical Examiner, Louisville, Kentucky, performed an autopsy of the pilot. His cause of death was multiple blunt force injuries to the body. Toxicology testing performed by the Federal Aviation Administration Forensic Sciences Laboratory detected ethanol and propanol in the pilot’s blood but not in his urine. Ethanol is a social drug commonly consumed by drinking beer, wine, or liquor. It acts as a central nervous system depressant; it impairs judgment, psychomotor functioning, and vigilance. After absorption, ethanol is quickly and uniformly distributed throughout the body’s tissues and fluids. Ethanol can be produced after death by microbial activity, sometimes along with other alcohols, such as propanol. ADDITIONAL INFORMATION Title 14 CFR 91.103 states that “each pilot in command shall, before beginning a flight, become familiar with all available information concerning that flight.” Federal Aviation Administration Advisory Circular 91-92, “Pilot’s Guide to a Preflight Planning” (dated March 15, 2021), provided information on preflight self-briefings, including planning, weather interpretation, and risk identification/mitigation skills. The advisory circular further stated in part the following: Pilots adopting these guidelines will be better prepared to interpret and utilize real-time weather information before departure and en route, in the cockpit, via technology like Automatic Dependent Surveillance-Broadcast (ADS-B) and via third-party providers.