CEN23FA095

The pilot’s decision to depart and continue the visual flight rules flight into night instrument meteorological conditions, which resulted in spatial disorientation and a loss of airplane control.

The non-instrument-rated pilot completed a cross-country flight on the morning of the accident in visual meteorological conditions. By the time he departed on what appeared to be a return flight to the airport of origin, weather conditions had deteriorated, and the forecast at the destination airport included 5 statute miles visibility, mist, and a broken ceiling at 800 ft above ground level (agl). Flight track information indicated that, about 2 hours after departure and about one hour after sunset, the airplane entered a decreasing-radius, 720° descending left turn from an altitude of about 4,500 ft mean sea level (msl). The airplane briefly resumed level flight at an altitude of about 3,300 ft msl before track data was lost in the vicinity of the accident site, about 16 nautical miles from the destination airport. Postaccident examination of the airplane did not reveal any preimpact anomalies. Review of weather conditions revealed that, about the time of the accident, the destination airport and another nearby airport both reported an overcast ceiling of 500 ft agl. Review of a model atmospheric sounding for the accident site indicated an overcast cloud layer from about 3,700 ft through 4,900 ft, the presence of icing below about 5,000 ft, and the potential for turbulence between about 10,000 ft and 4,400 ft, including extreme turbulence around 5,000 ft. There was no record of the pilot obtaining a weather briefing from an access-controlled source before departing on the accident flight. Toxicological testing of the pilot detected the synthetic opioid tramadol and its metabolites. Tramadol use may impair psychomotor functioning likely to be important in the performance of complex, divided-attention tasks such as flying. Opioid use can influence judgement and behavior and has been reported to increase the risk of spatial disorientation in pilots. In addition, opioid users have been shown to have decision-making deficits when compared to non-users. Given that the pilot did not hold an instrument rating, and his most recent recorded simulated instrument and night flight experience was about 10 years before the accident, the pilot was susceptible to the development of spatial disorientation while operating in night instrument meteorological conditions. The airplane’s decreasing-radius, descending turns depicted on ADS-B data just before the accident are consistent with the known effects of spatial disorientation. The extent to which his use of tramadol contributed to the loss of control or his decision to depart on or continue the flight into deteriorating weather conditions could not be determined based on the available information.

The weather conditions at LBL at the time of departure to FLY included wind from 310° at 5 knots, 10 statute miles or greater visibility, clear skies, temperature of -1°C and dew point temperature of -5°C, and an altimeter setting of 29.86 inches of mercury. When the airplane arrived at FLY, the reported weather conditions included wind from 060° at 7 knots, 10 statute miles or greater visibility, scattered clouds at 11,200 ft above ground level (agl), temperature 0°C, dew point temperature -7°C, and an altimeter setting of 29.82 inches of mercury. Around the time the pilot departed on the accident flight, the conditions at FLY included wind from 030° at 9 knots, 10 statute miles or greater visibility, scattered clouds at 2,100 ft agl, ceiling broken at 2,900 ft agl, ceiling broken at 4,600 ft agl, temperature -4°C, dew point temperature of -7°C, and an altimeter setting of 29.79 inches of mercury. At 1856, the reported conditions at LBL included wind from 040° at 19 knots with gusts to 22 knots, 10 statute miles or greater visibility, overcast ceiling at 500 ft agl, temperature -2°C, dew point temperature -3°C, and an altimeter setting of 29.93 inches of mercury. At 1855, the automated observation at Hugoton Municipal Airport (HQG), located about 11 miles north-northwest of the accident, reported wind from 040° at 14 knots with gusts to 19 knots, visibility 10 statute miles or greater, ceiling overcast at 500 ft agl, temperature -2°C, dew point temperature -3°C, and an altimeter setting of 29.93 inches of mercury. At 1731, a terminal aerodrome forecast (TAF) was issued for LBL that forecasted for the accident time wind from 030° at 15 knots with gusts to 24 knots, visibility of 5 statute miles, mist, and a broken ceiling at 800 feet agl. A High Resolution Rapid Refresh (HRRR) model sounding near the accident site at 1900 indicated an overcast cloud layer from about 3,700 ft through 4,900 ft. Freezing levels were identified at about 6,100 ft and 5,500 ft, with the presence of icing below about 5,000 ft. The potential for turbulence was identified between about 10,200 ft and 4,400 ft, with extreme turbulence around 5,000 ft. An AIRMET Zulu advisory was issued at 1500 for moderate icing between the surface and 19,000 ft msl. The advisory was active for the area of the accident site at the accident time. There was no record of the pilot obtaining a weather briefing before departure on the accident flight. According to data from the U.S. Naval Observatory, sunset occurred at 1806, with the end of civil twilight at 1833. The pilot did not hold an instrument rating. A review of his logbook revealed that his most recent night and simulated instrument flight experience was about 10 years before the accident flight. The pilot’s most recent third-class medical certificate was issued on November 9, 2022, and listed no limitations. On the application for that certificate, the pilot reported 120 hours of total flight experience, with 8 hours in the 6 months before the examination. The airplane’s maintenance records were not available for review. Documentation provided by the maintenance facility at LBL confirmed that the airplane’s most recent annual inspection was completed on August 30, 2022. The FAA Forensic Sciences Laboratory performed toxicology testing of postmortem specimens from the pilot. Tramadol was detected in cavity blood at 1025 ng/mL and in liver tissue at 6248 ng/g. O-desmethyltramadol was detected in cavity blood at 136 ng/mL and in liver tissue at 787 ng/g. N-desmethyltramadol testing was inconclusive in cavity blood. N-desmethyltramadol was detected in liver tissue at 414 ng/g. Tramadol is a synthetic opioid used to treat moderate to severe pain. It generally carries a warning that use may impair the mental and physical abilities required to drive a vehicle or operate heavy machinery. O-desmethyltramadol is an active metabolite of tramadol. N-desmethyltramadol is an inactive metabolite of tramadol. According to the FAA, tramadol is a “do not fly” medication. The airplane came to rest in a field with rolling terrain. All main airframe components were accounted for in the immediate area of the accident site. The forward fuselage was in a near-vertical position and the aft fuselage was bent downward relative to the forward fuselage. The wings remained partially attached to the fuselage and exhibited crushing damage to the leading edges consistent with a near-vertical impact. The empennage remained attached to the aft fuselage and was mostly intact. (See Figure 2.) The engine was located in position relative to the airframe, and the propeller remained secured to the engine. Figure 2. The airplane at the accident site. Examination of the airframe and flight control system at the accident site did not reveal any anomalies consistent with a preimpact failure or malfunction. Examination of the airplane’s engine after recovery from the accident site did not reveal any anomalies that would have precluded normal operation. On January 28, 2023, at 1902 central standard time, a Cessna 172 airplane, N6482B, was destroyed when it was involved in an accident near Hooker, Oklahoma. The pilot was fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. A review of ADS-B data provided by the Federal Aviation Administration (FAA) showed that the airplane departed Liberal Mid-America Regional Airport (LBL), Liberal, Kansas, at 0916, and proceeded to Meadow Lake Airport (FLY), near Colorado Springs, Colorado, landing at 1150. The airplane departed FLY at 1705 and proceeded in a southeasterly direction for about 1 hour and 53 minutes. The airplane’s altitude during the enroute portion of the flight varied. At 1859, from an altitude of about 4,500 ft mean sea level (msl), the airplane began a left turn with a decreasing radius that continued for two complete turns while the airplane descended to about 3,300 ft msl. The airplane exited the turns and proceeded on a course of about 150° for about ½ mile before the end of the data. A slight right turn began just before the data ended (see Figure 1). The accident location was about 200 ft west of the last recorded position, and 16 nautical miles west-southwest of LBL. Figure 1. Three-dimensional image of the final portion of the airplane’s flight path.