ERA24FA096

The pilots’ spatial disorientation in dark night visual meteorological conditions, which resulted in their failure to maintain altitude and a subsequent descent and impact with a swamp.

The pilots onboard the accident airplane took off under visual flight rules at night, and after about 8 minutes, turned toward an undeveloped wetland area where there was little to no ground lighting. About that time, the right-seat pilot sent a text message along with a photograph describing how dark it was outside. As the airplane continued flying, ADS-B data showed that its altitude varied between 1,600 and 1,000 ft before it began to descend at a rate of about 1,700 ft per minute; at the last ADS-B observed position, the descent rate had increased to 3,400 ft per minute. The airplane impacted the swampy area below about 1,000 ft beyond that last track data point. A postaccident examination of the wreckage found no evidence of any preimpact mechanical malfunctions or failures with the airplane that would have precluded normal operation. It could not be definitively determined which pilot was flying the airplane; however, it is likely that the left-seat pilot, who had rented the airplane, was flying with the right-seat pilot monitoring (based on statements from the operator). The investigation was also unable to determine the night or instrument currency of either the left- or right-seat pilot, as no logbooks were found for the left-seat pilot and the last non-draft electronic logbook entry for the right-seat pilot was from a year before the accident. Postmortem toxicological testing of samples from the left-seat pilot performed by the local medical examiner detected methamphetamine in blood and urine, whereas testing by the FAA Forensic Sciences Laboratory did not detect methamphetamine in blood, urine, or liver tissue. Neither laboratory detected the methamphetamine metabolite amphetamine. Even if only the peripheral blood methamphetamine level measured by one laboratory was considered, that level would not be indicative of whether methamphetamine was used medicinally or recreationally, nor would that level indicate specific associated effects, which might range from improved reaction time and decreased fatigue to increased risk-tolerance and psychomotor impairment. Some conditions that might be treated with methamphetamine also are potentially impairing, but the reviewed FAA medical certification and death investigation information for the left-seat pilot did not document any such condition. Overall, the left-seat pilot’s postmortem toxicological results were unclear as to his potential impairment. The low level of ethanol detected in the right-seat pilot’s blood, and the fact that ethanol was not detected in vitreous fluid or urine, indicated that some or all of the small amount of detected ethanol may have been from postmortem sources, and that the right-seat pilot was unlikely to have been impaired by ethanol effects at the time of the accident. The circumstances of this accident were consistent with the pilots experiencing spatial disorientation, most likely somatogravic illusion. An aircraft performance study found the apparent pitch angle (or the angle that would be “felt” by the pilots’ vestibular systems) remained nearly nose-level during the initial 20-seconds of the final descent. The night lighting conditions, and particularly the limited cultural lighting along the flightpath, would have made it difficult for the pilots to recognize that the airplane was descending if they were trying to utilize outside visual references to fly the airplane. By the time the pilots may have realized the airplane was descending, it would likely have been at an altitude too low for recovery.

The left seat pilot held a commercial pilot certificate with airplane single and multi-engine land ratings as well as an instrument airplane rating. The flight school owner reported that the left-seat pilot had about 600 hours of flight time, and the flight instructor who performed the pilot's flight review reported that the pilot had about 700 hours of flight time. Neither the flight instructor nor the flight school had obtained a copy of the pilot’s logbook, and the investigation was unable to locate any logbooks for the left-seat pilot. The left seat pilot’s night and instrument experience could not be determined. The flight instructor reported that the left-seat pilot appeared fit and in good health during their time together on the morning of the accident. He also reported that the left-seat pilot was not from the area and had come from Texas because he had liked the school when he was a student there. He further stated that the left-seat pilot had come back to rent and build flight time. The right seat pilot held a commercial pilot certificate with airplane single and multi-engine land, airplane single engine sea, and instrument airplane ratings. The flight school owner reported that the right-seat pilot had about 1,200 hours of flight time. A third-party logbook vendor reported that the right-seat pilot had an account with their services and provided a copy of his electronic logbook. Examination of this logbook revealed the first entry was on May 19, 2022, and the last entry was on January 16, 2023; at that time, the pilot had logged a total of 214.3 hours of flight time. An examination of FAA records showed that the pilot obtained all of his certificates and ratings before the start of the electronic logbook. The third-party logbook vendor also reported that the pilot had 57 “draft entries” (that is, automatically created entries that had not yet been reviewed by the pilot and approved), which dated from January 19, 2023, to January 20, 2024. All of the non-draft entries in the electronic log represented a total 62.4 hours of flight experience at night, 99.3 hours of flight experience under actual instrument conditions, and 4.8 hours of flight experience in simulated instrument conditions. An autopsy of the left-seat pilot was performed by the Broward County Medical Examiner. According to the autopsy report, the cause of death was multiple blunt force injuries with a contributory cause of drowning, and the manner of death was accident. The FAA Forensic Sciences Laboratory and the Broward County Office of Medical Examiner and Trauma Services Toxicology Laboratory performed toxicological testing of postmortem specimens from the left-seat pilot. Broward County detected methamphetamine at 50 ng/mL in peripheral blood and also detected methamphetamine in urine. The FAA did not detect any tested-for drugs in urine. An FAA forensic toxicologist reported that urine screening included a method capable of detecting methamphetamine levels as low as 1 ng/mL. The toxicologist further reported that, upon learning of the Broward County results, the FAA additionally performed confirmation testing of blood, urine, and liver tissue for methamphetamine and its metabolite amphetamine, using a method capable of quantitating levels of those analytes as low as 6.25 ng/mL; this testing was done for both pilots with negative results. Both the Broward County and FAA laboratories hold forensic toxicology accreditation and incorporate quality assurance measures into their procedures. According to an FAA forensic toxicologist, the two laboratories communicated about the discrepant methamphetamine results and were unable to identify an explanation. Methamphetamine is a central nervous system (CNS) stimulant drug. Methamphetamine is available as a Federal Schedule II controlled substance prescription medication used to treat attention-deficit/hyperactivity disorder (ADHD), narcolepsy, and occasionally obesity. As a medicine, the drug typically carries a warning that it may impair the ability to engage in potentially hazardous activities. Some conditions that might be treated with methamphetamine also are potentially impairing, but the reviewed FAA medical certification and death investigation information for the left-seat pilot did not document any such condition. The FAA considers methamphetamine to be a “Do Not Issue/Do Not Fly” medication. In addition to being used medicinally, methamphetamine may be produced illicitly and abused recreationally. At low doses used as part of appropriate medical treatment, methamphetamine may improve reaction time, cognitive function, and fatigue, but may result in people making higher-risk choices. At higher doses, the drug may have a variety of impairing effects on psychomotor function, cognition, and perception. Impairment related to methamphetamine use can result from drug or withdrawal effects, with features of CNS stimulation or CNS depression. A measured drug level does not indicate whether a person is experiencing early- or late-phase effects. In living people, blood methamphetamine levels of 20 ng/mL to 50 ng/mL are typical with medicinal use, while levels of 10 ng/mL to 2,500 ng/mL are typical with recreational use. Methamphetamine may exhibit postmortem redistribution. An autopsy of the right-seat pilot was performed by the Broward County Medical Examiner. According to the autopsy report, the cause of death was multiple blunt force injuries, and the manner of death was accident. The FAA Forensic Sciences Laboratory and the Broward County Office of Medical Examiner and Trauma Services Toxicology Laboratory performed toxicological testing of postmortem specimens from the right-seat pilot. FAA testing detected ethanol at 0.011 g/dL in blood. FAA testing did not detect ethanol in vitreous fluid or urine, and Broward County testing did not detect ethanol in blood or vitreous fluid. Ethanol is the intoxicating alcohol in beer, wine, and liquor, and, if consumed, can impair judgment, psychomotor performance, cognition, and vigilance, with detrimental effects on piloting tasks that worsen as ethanol levels increase. FAA regulation imposes strict limits on flying after consuming ethanol, including a prohibition on piloting a civil aircraft while having a blood ethanol level of 0.04 g/dL or greater. Alcohol consumption is not the only possible source of ethanol in postmortem specimens. Ethanol sometimes may be produced by microbes in a person’s body tissues and fluids after death. Typically, vitreous fluid, and to a lesser extent urine, are the specimen types best protected against microbial contamination, and therefore are less susceptible to postmortem ethanol production than are other specimen types. FAA testing also detected minoxidil in urine but not in blood for the right-seat pilot. Minoxidil can be used as a prescription oral medication for treatment-resistant high blood pressure, or (at low doses) for hair loss. There are some potential safety concerns with oral minoxidil use, and the drug carries a warning that its use for high blood pressure should be reserved for certain cases where multiple other medications have been ineffective. However, minoxidil also is commonly used in topical products available over the counter to promote hair growth. When used as directed topically, minoxidil is absorbed into circulation to a low extent only and is not typically impairing. According to the FAA, minoxidil is acceptable for pilots if the underlying condition is acceptable. FAA toxicology testing for the right-seat pilot also identified sildenafil in urine but not in blood, as well as desmethylsildenafil and salicylic acid in blood and urine. Sildenafil is a prescription medication commonly used to treat erectile dysfunction, as a sexual enhancement aid, or in the treatment of certain other conditions, including pulmonary hypertension. Sildenafil is not typically impairing, although the FAA states that pilots s