CEN23FA046

The pilot was flying the airplane in the traffic pattern when it descended into trees and terrain while on final approach to the runway. A review of aircraft track data and the wreckage debris path concluded that the airplane descended nearly wings-level into trees about 0.28 nautical miles (nm) from the runway threshold. A witness reported that he saw an airplane in a descent toward the airport and heard its engine running. There was no change in engine noise as the airplane descended below his sightline and then he heard a sound resembling a wood-chipper. Examination of the airplane, engine, and propeller revealed no evidence of a preimpact mechanical malfunction or failure that would have prevented normal operation, nor was there any evidence of a bird strike. The accident occurred about 9 minutes before sunset, with the sun positioned about 1.1° above the horizon and 27.5° left of the runway centerline. At the time of the accident, there was another pilot flying in the traffic pattern who reported being slightly disoriented by sun glare while he turned onto final approach. Aeromedical research suggests that sun glare can be visually debilitating and lead to operational errors and accidents. Specifically, sun glare during takeoff and landing phases can result in pilot perceptual issues that lead to collisions with objects or terrain when the pilot under- or over-shoots the runway and/or fails to maintain alignment with the runway. It is likely that the pilot became disoriented by sun glare after he turned the airplane onto final approach, which contributed to his failure to maintain a normal descent profile to the runway and the inflight collision with trees and terrain.

According to the FAA Civil Aerospace Medical Institute’s study, Natural Sunlight and Its Association to Aviation Accidents: Frequency and Prevention (DOT/FAA/AM-03/6), temporary visual impairment due to sun glare can have serious consequences for pilots during critical maneuvers performed at low altitude. The study was based on 130 NTSB accident investigations that cited sun glare as a contributing factor. The study determined that a majority (55%) of the reviewed accidents occurred during the approach/landing and takeoff/departure phases of flight, and a majority (72%) of those accidents also involved collisions with objects or terrain. Additionally, about 75% of those collisions were due to the pilot under- or over-shooting the runway and/or failing to maintain alignment with the runway, suggesting that the sun glare induced a pilot perceptual issue. The study concluded that glare from natural sunlight can be visually debilitating and lead to operational errors that can result in accidents. On November 25, 2022, about 1615 central standard time, an Extra EA 300/LC airplane, N361LX, was substantially damaged when it was involved in an accident near Wonder Lake, Illinois. The pilot was fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. A review of Federal Aviation Administration (FAA) automatic dependent surveillance-broadcast (ADS-B) data indicated that, at 1558, the airplane departed runway 27 at Galt Field Airport (10C), Wonder Lake, Illinois, and then entered a climbing right turn toward north and 3,000 ft mean sea level (msl), as depicted in Figure 1. Between 1559:15 and 1600:30, the airplane completed at least two aerobatic maneuvers about 1.8 nm north-northwest of 10C. Following the aerobatic maneuvers, the airplane flew east toward Antioch, Illinois. About 1605, the airplane entered a left 360° turn over a residential area located about 1.8 nm south of downtown Antioch, Illinois. The airplane’s altitude during the 360° turn was about 1,250 ft above ground level (agl). Following the 360° turn, the airplane turned northwest and climbed to about 2,700 ft msl. At 1608:30, the airplane turned west and descended to 2,400 ft msl. At 1610, about 1.7 nm north of Genoa City, Wisconsin, the airplane turned south and continued toward 10C. Figure 1. Plot of the airplane ground track for the accident flight. At 1613:12, the airplane entered the traffic pattern at 10C while on a left crosswind for runway 27, as depicted in Figure 2. The airplane was decelerating through 160 knots calibrated airspeed (KCAS) as it entered the traffic pattern, as shown in Figure 3. Between 1613:45 and 1614:30, the airplane made a 360° left turn while abeam the runway 27 threshold. The airplane’s altitude was about 1,800 ft msl (950 ft agl) during the 360° turn. After the 360° turn, the airplane entered a descending left base turn toward runway 27. During the descending turn, the airplane briefly decelerated to 70KCAS and achieved a maximum descent rate of about 1,700 feet per minute (fpm). At 1615:23, the final ADS-B data point was recorded about 0.31 nm from the runway 27 threshold. At that time, the airplane was at 922 ft msl, 84 KCAS, and descending about 900 fpm. The airplane had a 270.5° true heading, 2.7° left-wing-down roll, and -6.4° flight path angle. The airplane subsequently descended into trees about 0.28 nm from the runway 27 threshold. The airplane then continued a west trajectory before coming to rest about 0.24 nm from the runway 27 threshold. Figure 2. Plot of the airplane ground track while in traffic pattern. Figure 3. Plot of airplane altitude, ground speed, true airspeed, calibrated airspeed, and vertical speed. A review of downloaded engine monitor data confirmed that the engine was operating at the time of the accident. The engine’s cylinder head temperatures (CHT), exhaust gas temperatures (EGT), fuel flow, and total fuel used are depicted in Figure 4. The engine monitor did not record exhaust gas temperature for cylinder No. 2 during the accident flight or the previous flight flown on November 23, 2022. Figure 4. Plot of engine CHT, EGT, fuel flow, and total fuel used. At the time of the accident, there was a Piper PA-28-181 airplane flying in the runway 27 traffic pattern. The pilot of the Piper reported that as he entered the downwind leg he heard the pilot of the Extra 300/LC announce that he was entering the traffic pattern on the crosswind leg. The pilot of the Piper stated that he saw the Extra behind his position and that it appeared to be flying a higher speed relative to his airplane. The pilot of the Piper established radio contact with the pilot of the Extra over the common traffic advisory frequency, who acknowledged having the Piper in sight. The pilot of the Piper continued in the traffic pattern for runway 27. The pilot of the Piper recalled being slightly disoriented by sun glare while he turned onto final approach. After the Piper was established on final approach, the pilot of the Extra announced that he was turning onto base leg. The pilot of the Piper decided to conduct a touch-and-go landing to ensure adequate runway length for the Extra to land behind him. The pilot of the Piper completed an uneventful touch-and-go landing and then reentered the traffic pattern for a full-stop landing. Another witness, who was located east of the accident site, reported that he saw an airplane in a descent toward the airport and heard its engine running. There was no change in engine noise as the airplane descended below his sightline and then he heard a sound resembling a wood-chipper. According to the pilot’s autopsy report, as released by the McHenry County Coroner’s Office, the cause of death was blunt force injuries of the head and chest, and the manner of death was airplane crash. The FAA Forensic Sciences Laboratory completed postmortem toxicological testing of specimens obtained during the pilot autopsy. Losartanand Atorvastatin were detected in cavity blood and urine. There was no evidence of carboxyhemoglobin, ethanol, glucose, or drugs of abuse. Losartan (Cozaar) is an Angiotensin-Converting Enzyme Inhibitor (ACE-II) antihypertensive medication used to treat high blood pressure and is acceptable for pilots. Atorvastatin (Lipitor) is used to treat high cholesterol and is acceptable for pilots. At the time of the accident, day visual meteorological conditions prevailed with no clouds or visibility restrictions. The sun was positioned about 1.1° above the horizon and 27.5° left of the runway 27 centerline. The official sunset was at 1624:31, about 9 minutes after the accident. A pilot flight logbook was not located during the investigation. On his last FAA medical application, dated August 18, 2021, the pilot reported 6,200 hours total flight time, of which 50 hours were flown in the last 6 months. Based on a survey of the wreckage debris path, the airplane descended into 30-40 ft tall trees located about 195 ft from the final recorded ADS-B data point. The trajectory through the trees was on a 270° bearing and was aligned with the runway 27 centerline. The main wreckage was in a wooded area about 225 ft west of the initial tree impact. Examination of the airplane, engine, and propeller revealed no evidence of a preimpact mechanical malfunction or failure that would have prevented normal operation. There was no evidence of a bird strike during the flight. The fuel selector valve was using fuel from the center/aerobatic fuel tank at the time of the accident. Fuel was observed leaking from the impact-damaged gascolator at the accident site. Elevator and rudder flight control continuity was confirmed. Both wings separated from the fuselage and were fragmented during impact with trees and terrain. Aileron flight control continuity could not be established due to extensive wing damage; however, all observed control tube separations were consistent with impact-related damage.