N8680GHarvey J Brock TANGO 2 · 2019

On July 30, 2022, about 1005 eastern daylight time, an experimental amateur-built Tango 2 gyroplane, N8680G, was substantially damaged when it was involved in an accident near Melrose, Florida. The flight instructor and pilot under instruction were fatally injured. The gyroplane was operated as a Title 14 Code of Federal Regulations Part 91 instructional flight.

On the day of the accident, the flight instructor and pilot under instruction departed Melrose Landing Airport (FD22), Hawthorne, Florida at an unknown time. After the departure from FD22, witnesses observed and heard the gyroplane flying around the local area. One witness captured an image of the gyroplane passing over an auto parts store, and another witness estimated that the gyroplane was operating at an airspeed of 20 to 30 knots, about 1,000 ft above ground level. Just before the accident witnesses also heard additional noises coming from the gyroplane described as banging, whining, and the engine stopping. Some observed debris and objects fall from the sky, with some witnesses describing the loss of propellers, and/or rotor blades. They further described that the gyroplane did not autorotate, but descended rapidly, and was observed to spin, pitch over, tumble, and descend inverted. After impact, smoke and fire was also observed.

The flight instructor and pilot under instruction were married to each other. In addition to the gyroplane, they also had an Aeronca 7DC airplane, and a Piper PA-28-160 that they would fly.

Review of pilot logbooks indicated that the pilot under instruction held ratings for airplane single-engine land, and instrument airplane, but did not possess a rating for gyroplanes.

The flight instructor held a flight instructor certificate with a sport rating and endorsements for airplane single-engine land and gyroplane. He had been teaching the pilot under instruction how to fly the gyroplane. At the time of the accident, pilot logbooks indicated that he had given her about 9 hours of instruction in the gyroplane.

The accident aircraft was a gyroplane, which unlike a helicopter did not have a powered rotor. The rotor of the gyroplane would spin in flight due to the air loading on the rotor blades as the gyroplane moved forward. The free spinning rotor of the gyroplane did not require an anti-torque device, such as a tail rotor.

The gyroplane was comprised of an airframe equipped with a 28-ft, two bladed Chenaho rotor, a pre-rotator system, and tricycle type landing gear. It was configured with two seats mounted in a tandem configuration in open cockpits, with an aft-mounted vertical stabilizer and rudder and aft-mounted horizontal stabilizer.

According to Federal Aviation Administration (FAA) and aircraft maintenance records, the gyroplane’s special airworthiness certificate was issued on July 1, 2019. The gyroplane’s most recent condition inspection was completed (about 2 years before the accident) on August 1, 2020. At the time of the accident, the gyroplane and engine had accrued about 77 total hours of operation.

The accident aircraft was a gyroplane, which unlike a helicopter did not have a powered rotor. The rotor of the gyroplane would spin in flight due to the air loading on the rotor blades as the gyroplane moved forward. The free spinning rotor of the gyroplane did not require an anti-torque device, such as a tail rotor.

The gyroplane was comprised of an airframe equipped with a 28-ft, two bladed Chenaho rotor, a pre-rotator system, and tricycle type landing gear. It was configured with two seats mounted in a tandem configuration in open cockpits, with an aft-mounted vertical stabilizer and rudder and aft-mounted horizontal stabilizer.

According to Federal Aviation Administration (FAA) and aircraft maintenance records, the gyroplane’s special airworthiness certificate was issued on July 1, 2019. The gyroplane’s most recent condition inspection was completed (about 2 years before the accident) on August 1, 2020. At the time of the accident, the gyroplane and engine had accrued about 77 total hours of operation.

Examination of the accident site revealed that the gyroplane had impacted a pasture in a nose-low left bank and had come to rest on a magnetic heading of about 243°. Light items such as a seat cushion, flotation cushion, wheel pant, and a stick grip were thrown from the gyroplane during the impact sequence, but there was no wreckage path, and components recovered on scene were within close proximity to the main wreckage.

Examination of the gyroplane revealed that most of the front and rear cockpits were consumed by a postimpact fire. The left main landing gear was embedded in the ground, and the left outboard vertical stabilizer and left horizontal stabilizer were crushed inboard. The center vertical stabilizer and rudder were twisted and wrinkled from the root to the tip, and the right horizontal stabilizer was twisted and wrinkled from the root to the tip.

Flight control continuity was traced from the flight controls in the cockpit through breaks in the flight control system, and to the rudder and rotor head.

Examination of the rotor system revealed that one rotor blade was missing. Further examination revealed that the missing blade had separated about 2 inches outboard of the blade grip and its associated teeter stop (droop stop) was bent in a downward direction. The remaining blade’s droop stop was slightly bent (as compared to the other droop stop), and the blade was bent in two places. It also displayed a black witness mark on the bottom of the blade about 4 ft outboard of the rotor hub (which corresponded to the position of the propeller). The blade also had a blue paint transfer mark on the bottom of the blade about 3 ft inboard of the blade tip (which corresponded to the position of the vertical stabilizer), and areas of damage from the impact sequence along the blade span. The rotor head and hub bar were intact, and the mechanism would rotate and teeter when manipulated by hand.

Examination of the pre-rotator system revealed that it had been damaged during the impact sequence, but continuity was traced from the pre-rotator drive through breaks in the system to the pre-rotator, and it would rotate when turned by hand.

Examination of the three-blade pusher propeller revealed that the propeller hub had remained attached to the propeller speed reduction unit (PSRU). Two of the propeller blades were broken off about 8-inches outboard of the propeller hub. The one remaining blade was intact.

Examination of the PSRU revealed that it still contained oil, and it would rotate by hand. The centrifugal clutch was also intact and did not display any indication of damage.

Examination of the engine revealed that it had remained in its mounts, had received thermal and fire damage, and the drivetrain could not be rotated. The timing chain was intact, and both camshafts were intact and undamaged. All intake and exhaust valves were also intact and no blockages in the exhaust system were discovered.

Oil was present in the engine and oil pump, and the oil pump was functional. The oil filter and internal pleated filter material had been thermally damaged. No metallic debris was found internally. The ignition system and fuel injection system, including the throttle bodies and their associated assemblies, were all fire damaged.

The water pump was intact, but internal examination revealed that the impeller had melted. The radiator was intact and no blockages were discovered.

On August 3, 2022, about 4 days after the accident, the missing rotor blade was discovered in a wooded area about 312 ft east-northeast from the main wreckage.

Materials Laboratory Examination

The separated portion of rotor blade and the rudder push rod were submitted to the National Transportation Safety Board Materials Laboratory for examination.

During the examination, the separated portion of the rotor blade was aligned with its corresponding portion of rotor blade still attached to the rotor head. The alignment followed the curvature of the deformed rotor blade across both sides of the fracture. This alignment exhibited that the rotor blade bent in an upward direction more than 45° before separation.

The fracture surface on the separated portion of the rotor blade exhibited slant fractures consistent with overstress. The upper surface of the rotor blade in proximity to the fracture exhibited ridges consistent with deformation caused by compression. The lower surface of the rotor blade in proximity to the fracture exhibited cracking and stretcher strain marks consistent with deformation caused by tension.

The rudder push-pull rod end exhibited a fracture in the threaded shank right above the nut at the end of the rod. The threaded shank exhibited bending deformation and slant fractures consistent with bending overstress.

Flight Instructor

The Florida 4th District Medical Examiner’s Office performed the flight instructor’s autopsy. According to the flight instructor’s autopsy report, his cause of death was multiple blunt injuries and his manner of death was accident. The extent of injury severely limited structural evaluation of the heart. Moderate aortic atherosclerosis was present and the kidneys exhibited changes that may be seen with chronic high blood pressure. His autopsy did not identify other natural disease.

At the request of the Medical Examiner’s Office, NMS Labs performed toxicological testing of postmortem liver tissue from the flight instructor. NMS labs detected ethanol at 0.27 g/hg in the tested liver tissue.

The FAA Forensic Sciences laboratory also performed toxicological testing of postmortem specimens from the flight instructor. Ethanol was not detected in tested liver or brain tissue specimens. Fentanyl was detected in liver tissue at 0.4 ng/g, in lung tissue at 0.7 ng/g, and in kidney tissue at 1 ng/g; fentanyl testing in brain tissue was inconclusive, and fentanyl was not detected in bile. Hydroxyzine was detected in heart tissue but not in liver tissue. Losartan, amlodipine, and metoprolol were detected in liver tissue and muscle tissue. No blood was available for FAA testing.

Ethanol is a type of alcohol. It is the intoxicating alcohol in beer, wine, and liquor, and, if consumed, can impair judgment, psychomotor performance, cognition, and vigilance. FAA regulation imposes strict limits on flying after consuming ethanol, including prohibiting pilots from flying with a blood ethanol level of 0.04 g/dL or greater. However, consumption is not the only possible source of ethanol in postmortem specimens. Ethanol can be produced by microbes in a person’s body after death. Postmortem ethanol production is made more likely by extensive traumatic injury and can cause an affected toxicological specimen to test positive for ethanol while another specimen from the same person tests negative.

Fentanyl is an opioid drug that has central nervous system depressant effects. It may be used medicinally as a powerful prescription painkiller, or illicitly by users seeking a euphoric effect. Fentanyl used medicinally may be administered by injection, as a skin patch, by mouth, under the tongue, inside the cheek, or as a nasal spray. Fentanyl used illicitly may be injected, snorted, smoked, ingested, or taken under the tongue or inside the cheek. Illicit fentanyl may be sold alone or may be an adulterant in other illicit drugs. Fentanyl is a Schedule II controlled substance under federal law, with a high potential for abuse and dependence. Fentanyl can cause drowsiness, confusion, and dizziness. Fentanyl medication typically carries a warning that it may impair the mental or physical abilities required for the performance of potentially dangerous activities. The FAA considers fentanyl to be a “do not issue/do not fly” medication.

Hydroxyzine is a prescription sedating antihistamine medication typically used for the treatment of itching, hives, and anxiety. It may also be used to treat motion sickness/nausea or as a sleep aid. Sedating antihistamines can cause cognitive and psychomotor slowing and drowsiness. Hydroxyzine typically carries a warning that users should be cautioned against driving or operating dangerous machinery while taking the drug. The FAA states that a pilot who uses a sedating antihistamine should not fly until sufficient time has elapsed for the drug to be cleared from circulation. Additionally, some underlying conditions for which hydroxyzine is used may be disqualifying for FAA medical certification.

Losartan, amlodipine, and metoprolol are prescription medications of three different classes (angiotensin receptor blocker, dihydropyridine calcium channel blocker, and cardioselective beta blocker, respectively) that can be used to treat high blood pressure. Additionally, losartan and metoprolol each may be used in the treatment of heart attack and certain types of heart failure, amlodipine and metoprolol each may be used in the treatment of heart-related chest pain, and metoprolol may be used in the treatment of certain types of irregular heartbeat or to help prevent migraine headache.

Pilot Under Instruction

The Florida 4th District Medical Examiner’s Office performed the autopsy of the pilot under instruction. According to the autopsy report of the pilot under instruction, her cause of death was multiple blunt injuries and her manner of death was accident. The extent of injury severely limited structural evaluation of her heart. Her autopsy did not identify significant natural disease.

At the request of the Medical Examiner’s Office, NMS Labs performed toxicological testing of postmortem liver tissue from the pilot under instruction. NMS labs detected ethanol in the tested liver tissue but was unable to obtain a reproducible measurement of the ethanol concentration.

The FAA Forensic Sciences laboratory also performed toxicological testing of postmortem specimens from the pilot under instruction. Diphenhydramine was detected in liver tissue and muscle tissue. Ethanol was not detected in liver tissue or brain tissue. There was no blood available for FAA testing.

Diphenhydramine is a sedating antihistamine available over the counter in multiple sleep aids and cold and allergy products. Diphenhydramine can cause cognitive and psychomotor slowing and drowsiness. It typically carries a warning that it may impair performance of tasks like driving and operating heavy machinery. The FAA states that pilots should not fly within 60 hours of using diphenhydramine, to allow time for it to be cleared from circulation.