- Location: Trenton, Maine
- Accident Number: ERA24FA323
- Date & Time: July 25, 2024, 12:27 Local
- Registration: N990PT
- Aircraft: CIRRUS DESIGN CORP SR22
- Aircraft Damage: Destroyed
- Defining Event: Loss of control in flight
- Injuries: 2 Fatal
- Flight Conducted Under: Part 91: General aviation - Personal
https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/194767/pdf
https://data.ntsb.gov/Docket?ProjectID=194767
On July 25, 2024, about 1227 eastern daylight time, a Cirrus Design Corp SR22 airplane, N990PT, was destroyed when it was involved in an accident near Trenton, Maine. The pilot and passenger were fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.
The pilot received a weather briefing package from a commercial service when he filed his instrument flight rules (IFR) flight plan before departing on the accident flight. The weather briefing information the pilot received included forecasts and AIRMETs for low IFR (LIFR) conditions at the destination airport during the planned time of arrival (LIFR, refers to a cloud ceiling below 500 ft above ground level [agl] and/or visibility less than 1 mile). Reported conditions at the destination airport about 31 minutes before the accident included visibility of 1.5 miles in light rain and mist and an overcast ceiling at 300 ft agl. As the flight neared the destination airport, an air traffic controller provided the pilot with a radar vector, cleared the flight for an instrument landing system (ILS) approach. The ILS approach specified a minimum visibility of 3/4 mile and a decision height of 200 ft agl, or 283 ft mean seal level (msl).
A review of flight data parameters downloaded from the airplane’s recoverable data module (RDM) revealed that the airplane’s autopilot was engaged for nearly the entire flight, from shortly after takeoff to about 17 seconds before the accident. The data showed that, after the controller cleared the flight for the approach, the airplane turned to the assigned heading vector, then it turned to a heading consistent with the final approach segment and began a descent toward the runway. When the airplane was about 200 ft msl (or about 117 ft agl) and about 0.4 nautical mile (nm) from the runway threshold with the flaps fully down, the autopilot was disengaged. The airplane’s pitch angle then increased rapidly to about 30° nose-up, its vertical ascent rate reached about 2,350 ft per minute (fpm), its flaps were reduced to 50%, and it climbed to about 450 ft msl, where it remained for about 2 seconds before it began to descend. The airplane then transitioned to an extreme nose-down pitch and extreme left-bank roll while its engine power increased. It briefly rolled back toward wings-level before again entering a left-bank roll, and its descent rate increased to about 4,000 fpm before the data ended.
A witness outside at the airport stated that he heard the airplane’s engine noise go to full power, and, when he looked up, he saw the airplane in a sharp left turn before it descended to the ground. He stated that the weather conditions were “brutal” and that he could barely see the airplane at 200 yards away due to the thick fog. A witness who was driving a car near the airport captured video of the airplane in an uncontrolled descent, coming into view as it descended below a low cloud/fog layer.
The airframe was largely consumed by a postimpact fire that precluded a detailed examination of flight control continuity; however, all major components of the airplane were identified. Examination of the identified airframe components and the engine revealed no evidence of any preimpact malfunction, and a review of engine data parameters recovered from the RDM revealed that the engine operated normally throughout the flight.
The autopsy of the pilot indicated cardiovascular disease that could be associated with increased risk of an impairing or incapacitating cardiovascular event such as heart attack or stroke. Although such an event cannot be excluded by autopsy evidence alone, there is no evidence that such an event occurred. Postmortem toxicology testing detected the opioid codeine, the codeine metabolite morphine, and thebaine. The presence of thebaine is not explained by pharmaceutical codeine use and likely indicates poppyseed consumption. It is possible that the measured codeine and morphine levels might be attributable to poppyseed consumption alone, although the possibility that codeine was also used cannot be excluded. Regardless, the codeine concentration in postmortem heart blood was low, and no morphine was detected in blood. As such, there is no clear evidence that the pilot was impaired by opioid effects at the time of the accident. Overall, there is no clear indication from reviewed evidence that the pilot was significantly impaired by effects of medical conditions or medications, but this possibility cannot be excluded given his identified risk factors for impairment.
The pilot’s logbooks were not recovered, so his total or recent experience flying in instrument meteorological conditions (IMC) was not known. Based on the available weather information, it is likely that the airplane was in IMC as the pilot descended on autopilot below the ILS approach decision height. The pilot’s subsequent actions while hand-flying the airplane, which included increasing the airplane’s pitch, reducing the flaps, and increasing engine power, were consistent with the initiation of a missed approach.
Although vestibular illusions are commonly experienced by pilots during maneuvering flight in IMC, the accident pilot’s aggressive pitch control inputs while executing the missed approach likely intensified such vestibular illusions, increasing the likelihood of his experiencing spatial disorientation. The airplane’s subsequent extreme nose-down pitch and extreme left roll were consistent with the pilot’s loss of airplane control due to spatial disorientation.
- Probable Cause: The pilot’s aggressive pitch and power control inputs while executing a missed approach, which resulted in his spatial disorientation and a loss of airplane control.
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