ERA23FA138

The pilots’ exceedance of the airplane’s critical angle of attack following a go-around/low pass over the runway, which resulted in a loss of control and impact with terrain.

The right-seat pilot, who held a flight instructor certificate, and the left-seat pilot, who held a private pilot certificate, arrived at the destination airport in night visual meteorological conditions. Two witnesses who were at the airport waiting to meet the accident pilots reported that the airplane descended on final approach to 20 to 30 ft above the runway. They then observed a go-around, which the pilots did not announce on the airport’s common traffic advisory frequency (CTAF). The witnesses reported that the airplane flew above the runway and did not climb any higher than 200 to 250 ft above ground level. Upon reaching the departure end of the runway, the airplane banked to the right, stalled, and rolled inverted before impacting the ground. The witnesses did not report hearing any engine discrepancy during the approach or go-around, but one witness reported the engine did not seem to the operating at full power during the go-around. Videos of the airplane taken by one of the witnesses captured a portion of the go-around and the moments just before the accident. Analysis of the videos determined that the engine rpm was about 2,400 before the right turn, after which engine rpm decreased slightly to around 2,300. Examination of the airplane revealed that the wing flaps were retracted, and there was no preimpact failure or malfunction of the flight controls. Examination of the engine powertrain, air induction, exhaust, and ignition systems revealed no evidence of preimpact failure or malfunction. One fuel injector nozzle and an attached fuel line was separated from its cylinder; however, this was likely the result of impact damage. The witnesses did not report anything unusual about the approach that would have required a go-around, nor was there any communication from the pilots on the CTAF or to either witness about a go-around. It is possible that the go-around and subsequent low pass were performed for the benefit of the witnesses, who were known by at least one occupant of the airplane to be waiting for the airplane’s arrival. Although the engine was operating just below full power before the in-flight loss of control, and the throttle control was found separated, the throttle control system was equipped with a spring that would have moved the throttle control full forward in the event of separation of the throttle control cable. Thus, the reduced power setting was likely an intentional setting by the pilots rather than a separation of the throttle control cable or an engine malfunction. Toxicology testing revealed that the left-seat pilot had used a product containing delta-8-THC, which has the potential to alter perception and cause impairment; however, the measured delta-8-THC levels in his cavity blood and urine could not be used to determine whether or to what degree he may have experienced associated impairing effects. With the non-psychoactive metabolite of delta- 9-THC detected, and no delta-9-TCH or psychoactive metabolite of delta-9-THC detected, it is unlikely that delta-9-THC use contributed to the accident. While the flight instructor did not hold an FAA medical certificate, no significant natural disease was found at autopsy and there was no evidence that his previously reported obstructive sleep apnea contributed to the accident. The circumstances of the accident are consistent with the pilots’ exceedance of the airplane’s critical angle of attack while maneuvering after a go-around/low pass, which resulted in an aerodynamic stall, loss of control, and impact with terrain.

Left-Seat Pilot The left seat pilot held a private pilot certificate with a rating for airplane single-engine land. His logbook began with an entry dated September 12, 2007, to the last entry dated February 4, 2023, and indicated that his most recent flight review was on July 19, 2022. He logged a total of 4.4 hours night flight time all as dual received, with his last logged night flight on March 7, 2011. Right-Seat Pilot The right-seat pilot held a commercial pilot certificate with ratings for airplane single-engine land and sea, and a flight instructor certificate with ratings for airplane single-engine and instrument airplane. A review of the right-seat pilot’s logbook revealed that his most recent flight review was on October 26, 2022, when he added an instrument rating to his flight instructor certificate. After his medical had expired, he logged 4 separate flights as pilot-in-command; the remarks section of those flights listed names consistent with instruction given. His last logged night flight as a flight instructor and pilot-in-command was on January 4, 2023, in a Diamond DA-40. The entire portion of the 1.2-hour-long flight was logged as night. According to the right-seat pilot’s medical records, his last aviation medical examination was on February 15, 2022. At that time, he reported, in part, obstructive sleep apnea with use of a continuous positive airway pressure (CPAP) machine, which was found in the wreckage. He was issued a first-class medical certificate with a time limitation (not valid for any class after February 28, 2023). According to medical records from the Veteran’s Affairs Medical Center (VAMC), he was evaluated by his VAMC sleep physician on February 14, 2023. According to the sleep physician’s documentation, the pilot’s CPAP record from February 14, 2022 to February 13, 2023, was reviewed and the pilot had been adherent to his prescribed CPAP therapy. The reviewed CPAP records show the pilot used the machine an average time on the days used of 7 hours 57 minutes, and usage on 99% of the days during the time period reviewed. There was no record that he obtained another FAA-issued medical after February 28, 2023. As part of the airplane’s last annual inspection on February 24, 2023, the throttle cable was adjusted and secured. The airplane was approved for return to service. According to the operator’s chief pilot, the recently leased airplane was being flown to their facility at LNA. Since taking possession of the airplane on the day of the accident at Henderson City-County Airport (EHR), Henderson, Kentucky, the airplane was flown to Harris County Airport (PIM), Pine Mountain, Georgia, then to Williston Municipal Airport (X60), Williston, Florida, arriving there about 1840. The chief pilot indicated that the fuel tanks were topped off at X60. Metering of fuel delivered to the engine was performed by a servo fuel injector, which was controlled from the cockpit at an engine control assembly in the center console that held the throttle and mixture control levers. The throttle control lever in the cockpit sets the position of the throttle control lever at the fuel servo and the two ends are mechanically connected by a Bowden cable. The engine-compartment end of the throttle control cable has a cable eye, or rod end, that attaches to the throttle control lever at the fuel servo. The throttle control cable attach hardware in the engine compartment was equipped with a spring that attached to the hardware securing the throttle cable to the throttle lever at the fuel servo and also to a spring anchor bracket attached to the fuel servo. The spring was designed and part of the initial type certification so that if the throttle control separated at the engine fuel metering device, the tension spring was intended to move the throttle control to full power. Two mini iPads, two cellular phones, and an Apple Series 6 watch were recovered from the wreckage and submitted to the NTSB Vehicle Recorder Division for download; however, the extent of damage precluded obtaining any data. Postmortem examinations of both pilots were performed by the District 15 Medical Examiner’s Office, West Palm Beach, Florida. The cause of death for both was specified to be total body blunt trauma, and there was no significant natural disease found of the right-seat pilot. Forensic toxicology testing was performed on specimens of both pilots by the FAA Forensic Sciences Laboratory and Axis Forensic Toxicology (AFT). The toxicology report for the left-seat pilot by the FAA indicated that Carboxy-delta-9-THC was detected in urine at 3.6 ng/mL. Carboxy-delta-9-THC was not detected in cavity blood. Delta-8-THC was detected in cavity blood and urine at low levels. Carboxy-delta-8-THC was detected in cavity blood at 1 ng/mL and in urine at 48 ng/mL. Losartan was detected in urine and was not detected in cavity blood. Testing by AFT confirmed caffeine was presumptively detected in heart blood while Carboxy-THC was detected in urine. Carboxy-delta-9-THC is a non-psychoactive metabolite of delta-9-THC, which was not detected in this case. Delta-9-THC is the primary psychoactive chemical in cannabis, including marijuana, hashish, and other cannabis products. The specific psychoactive effects of delta-9-THC vary depending on the user, user history of use, dose consumed, and route of consumption. Effects of delta-9-THC consumption may impair motor coordination, decrease reaction time, impair decision making and problem solving, distort perceptions of reality, and decrease vigilance. Delta-9-THC is a federally controlled substance, and the FAA considers it unsuitable for flying, regardless of state cannabis laws. Delta-8-THC is a psychoactive compound typically chemically manufactured from cannabidiol (CBD), a chemical in the cannabis plant. It has similar psychoactive effects as delta-9-THC such as cognitive impairment including decreased processing speed of information, distorted perception, visual disturbances and decreased attention and response time. Delta-8-THC containing products are often marketed simply as “hemp” or “CBD” products, which consumers may not associate with potential psychoactive effects. Delta-8-THC is available in a variety of over-the-counter products for oral consumption, smoking, and inhalation and vary widely in potency of delta-8-THC and content of delta-9-THC. Delta-8 THC products have not been evaluated or approved by the US Food and Drug Administration for safe use in any context. Caffeine is a central nervous system stimulant that is commonly ingested, including in coffee, tea, soft drinks, and chocolate, and is also an ingredient in certain anti-drowsiness medications and headache medications. Losartan is a prescription medication commonly used to treat high blood pressure. Caffeine and losartan are not generally considered impairing. FAA toxicology testing of the right-seat pilot’s submitted specimens identified ibuprofen in urine, but it was not detected in cavity blood. The test results by AFT were positive for caffeine in cavity blood. Ibuprofen is a non-prescription medication commonly used to treat mild to moderate pain and fever; caffeine and ibuprofen are not generally considered impairing. The airplane crashed on airport property about 1,030 ft and 191° from the departure end of runway 10. Examination of the accident site revealed a ground scar consistent with impact with the left wing, indicating that the airplane was on a magnetic heading of 228°. The airplane came to rest upright leaning on its right side on a magnetic heading of 221°. The left wing was fragmented, while the right wing remained intact but impact damaged. About 6 gallons of fuel were drained from the right wing fuel tank. The aft empennage was displaced to the left. All major components of the airplane either remained attached or were found in close proximity to the main wreckage. Examination of the elevator, ailer