CEN24FA298

The pilot’s husband reported that his wife was conducting an evening pleasure flight in the accident gyroplane. He heard the gyroplane taxi to the runway and begin its takeoff. He said he did not hear anything unusual until he heard two loud thumps. The gyroplane was later located in a wooded area left of the departure runway. There were no witnesses to the accident and no flight track data was available. Examination of the gyroplane did not reveal any preimpact anomalies that would have precluded normal operations. The gyroplane’s tail surfaces were found separated from the rest of the gyroplane with unbroken trees between the resting location of the tail surfaces and the main wreckage. Additionally, impact marks and paint transfer on the rotor blades, tail, and tail boom were consistent with the main rotor blades impacting the tail. It is most likely that the main rotors impacted the tailboom which resulted in the separation of the tail. Main rotor blade contact with the tail would have rendered the gyroplane uncontrollable. Based on the design of the gyroplane, the rotor blades would have had to droop a significant amount in order to contact the tail boom. Without flight track, engine, or rotor speed data to assist the investigation, the reason that the main rotor blade contacted the tail boom could not be determined. The pilot’s postmortem toxicological testing indicated that the pilot had used the sedating antihistamine medication diphenhydramine. However, diphenhydramine testing in cavity blood was inconclusive. Based on these results, it was not possible to determine whether the pilot had used diphenhydramine recently enough to be experiencing impairing effects at the time of the accident

The accident gyroplane was an original concept that was designed and constructed by the pilot’s husband. It had several unique features that distinguished it from more common gyroplanes. A portion of the engine’s power was continuously supplied to drive the main rotor system, which has cyclic and collective controls. Yaw was controlled by a moveable vertical tail surface. The private airstrip consisted of a single turf runway oriented about 160°/340° with trees lining the majority of the length on both sides. The accident takeoff was made on runway 34. On August 3, 2024, about 2058 central daylight time, a De Bird gyroplane, N140DG, was substantially damaged when it was involved in an accident near Napoleon, Michigan. The pilot was fatally injured. The gyroplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The husband of the pilot reported that his wife was conducting an evening pleasure flight in the gyroplane. He said that the weather conditions at the time of the accident were good. He was about ¼ mile away from their private airstrip and he could hear the gyroplane as it advanced down the runway, took off, and began its climb. He said that he did not hear anything unusual until he heard two loud thumps. He noted that during a normal takeoff the gyroplane would be about 150 ft above ground level (agl) when it reached the departure end of the runway. After hearing the thump noises, he boarded and took off in another gyroplane that he owned to search for the accident gyroplane, but could not locate it. When asked if he heard any unusual engine sounds, he said that he could not be sure as the gyroplane was farther away from his location after starting the takeoff. The accident gyroplane was later located in wooded terrain about 200 ft left of the runway centerline and about 250 ft short of the departure end of runway. No flight track data for the gyroplane was available from either ground- or aircraft-based systems. The Jackson County, Michigan, Medical Examiner’s Office conducted an autopsy of the 83-year-old female pilot. According to the autopsy report, the cause of death was blunt force chest trauma, and the manner of death was accident. The FAA Forensic Sciences Laboratory performed toxicological testing of postmortem specimens from the pilot. This testing detected diphenhydramine in urine. Diphenhydramine testing in cavity blood was inconclusive. Diphenhydramine is a sedating antihistamine medication widely available over the counter in multiple sleep aids and cold and allergy products. Diphenhydramine can cause cognitive and psychomotor slowing and drowsiness, and often carries a warning about driving and operating machinery. FAA guidance indicates that pilots should not fly within 60 hours of using diphenhydramine, to allow time for it to be cleared from circulation. The pilot’s logbook was not available for review; however, the pilot reported having 2,100 hours of total flight experience at her lastmedical examination about 13 years before the accident. In addition, the pilot’s husband reported that his wife was very experienced in the accident gyroplane. He estimated that she had about 800 flight hours in the accident gyroplane. The gyroplane involved in the accident met the requirements to qualify as a light sport aircraft. At the time of the accident, operation of light sport aircraft did not require a current FAA-issued medical certificate. The gyroplane was found upright but leaning to its left side and supported by trees. The forward and left sides of the fuselage were crushed. The left main landing gear was fractured. The horizontal and fixed tail surfaces were found a short distance away from the fuselage on opposite sides of surrounding trees. The tail surfaces had two separate areas of damage. Examination of the main rotor blades revealed yellow paint transfer consistent with the color of the tail of the gyroplane. The tail boom of the gyroplane was partially separated from the fuselage and only remained attached by the two rudder cables. The fracture of the tail boom was consistent with the aft end of the boom bending toward the right before it partially separated. Viewed from above, the main rotor blades rotated counterclockwise. The accident gyroplane’s flight control system consisted of a cyclic control and a collective control, which adjusted the main rotor blade pitch dependent on the blade location while rotating. Directional control was accomplished by a single moveable vertical surface below the horizontal stabilizer and between the two fixed vertical stabilizers. Examination of the gyroplane’s control system confirmed continuity of the cyclic, collective, and directional control systems. All identified separation points were consistent with impact damage. Examination of the gyroplane’s engine was limited but continuity of the powertrain and valvetrain was verified by rotating the engine. During rotation, compression could be felt on all cylinders. No preimpact anomalies were found during the examination. The rotor drive system was intact except for a separation of the drive coupling in the top of the fuselage. All three main rotor blades were intact from root to tip but with bending at various locations along their length consistent with impact. All of the main rotor system components were intact with all damage consistent with impact damage.