CEN21FA426

The pilot of the airplane was holding short of the runway for takeoff when he asked the pilot of an inbound helicopter to side-step to the taxiway so that the airplane could depart. The helicopter pilot reported that a side-step would have resulted in the helicopter flying directly over the airplane and that he side-stepped the helicopter toward the taxiway after clearing the airplane. An airport surveillance camera captured the airplane start the takeoff roll after the helicopter passed. Shortly after takeoff, the airplane entered a steep roll and impacted the runway. A postimpact fire ensued. Toxicology testing of the pilot was positive for ethanol in blood, vitreous fluid, urine, gastric contents, and liver tissue. The ethanol in blood concentration (0.108 gm/dL) was associated with impairment, and alcohol consumption was fairly recent to the accident based on the concentration levels in the pilot’s body. The pilot completed building the airplane about 5 months before the accident. The engine had a history of high oil and cylinder head temperatures, which may have been a factor in the pilot’s decision to depart so soon after the helicopter to reduce idling time on the ground. Based on the available information, it is likely that the airplane encountered wake turbulence from the landing helicopter during takeoff, which resulted in the pilot’s loss of control. It is likely that the pilot’s impairment from ethanol contributed to the accident.

According to the Pilot’s Handbook of Aeronautical Knowledge (FAA-H-8083-25B), Chapter 5, Avoiding Wake Turbulence: A helicopter generates a down wash from its main rotor(s) similar to the vortices of an airplane…In forward flight, this energy is transformed into a pair of strong, high-speed trailing vortices similar to wing-tip vortices of larger fixed-wing aircraft. Helicopter vortices should be avoided because helicopter forward flight airspeeds are often very slow and can generate exceptionally strong wake turbulence. The kit airplane was built by the pilot and the FAA granted a special airworthiness certificate in April 2021. According to maintenance records and a newsletter article written by the pilot, the airplane had a history of high engine oil and cylinder head temperatures. On September 18, 2021, about 1845 eastern daylight time, a Rans S-20 airplane, N6915G, was destroyed when it was involved in an accident at Wadsworth Municipal Airport (3G3), Wadsworth, Ohio. The pilot was fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. A review of airport surveillance video revealed that a Sikorsky S-76 helicopter was on approach to Runway 2 as the accident airplane taxied to the runway. According to the helicopter pilot, the accident pilot requested that the helicopter side-step to the west of the runway to facilitate the airplane’s departure. A few seconds after the helicopter flew over the approach end of runway 2, the accident pilot taxied onto the runway and started the takeoff roll. Soon after liftoff, the airplane entered a steep roll, descended, and impacted the runway (see figure 1). A postimpact fire ensued. Figure 1. Screenshot of airport surveillance video. Red arrow points to accident airplane. Toxicology testing performed by the FAA Forensic Sciences Laboratory detected ethanol at 0.108 grams per deciliter (gm/dL) in the pilot’s blood. Ethanol was detected in his vitreous fluid at 0.119 gm/dL, urine at 0.075 gm/dL, gastric contents at 0.484 gm/dL, and liver tissue at 0.072 grams per hectogram. Most of the airplane was destroyed by the postcrash fire (see Figure 2). Figure 2 – Airplane at Accident Site Examination of the wreckage did not identify any pre-impact anomalies that would have precluded normal operation.