ERA23FA219

The pilot’s decision to continue an instrument flight into an area of forecast weather with severe to extreme turbulence associated with a line of thunderstorms, which resulted in an in-flight breakup. Contributing was the pilot’s operation of the airplane in excess of its published maneuvering speed.

The instrument-rated private pilot departed on an instrument flight rules (IFR) flight and climbed to 9,000 ft mean sea level (msl) on a southeast heading. Radar data indicated that for about the first 2 hours and 30 minutes, the airplane maintained a relatively straight course. Twice the pilot requested air traffic control (ATC) provide radar vectors around weather, confirming with one controller that the airplane was equipped with on-board weather observation capability. During cruise flight, while flying at an airspeed above the airplane’s published maneuvering speed in an area with a valid Convective SIGMET, the airplane encountered the leading edge of precipitation and building cumuliform clouds in convective updrafts. This weather system was associated with a line of forecast thunderstorms and other pilots had reported the presence of severe to extreme turbulence while flying in the vicinity of it. The accident airplane’s heading and altitude changed several times during the final portion of the flight, and these deviations were not instructed by the controller or announced by the pilot. Following a second right turn the controller commented to the pilot, “it looks like you are in a little bit of a descent in a turn is everything alright?” The pilot did not reply to that communication and radar contact with the airplane was lost. A radar performance study indicated that when the airplane was last observed by radar, while flying at an altitude of about 8,850 ft msl, it was operating at a calibrated airspeed of 134 knots, which was 35 knots greater than the published maneuvering speed. Although the radar data did not capture the final descent, the airplane likely began descending after encountering severe to extreme turbulence. During that descent, the airplane’s airspeed which was already well above the published maneuvering speed likely increased and an in-flight break-up occurred, separating both wings and a majority of the right horizontal stabilizer and right elevator from the fuselage. The postaccident examination of the airframe revealed that all fracture surfaces displayed features consistent with overload failure with no evidence of preexisting cracking. The examination of the engine revealed no evidence of any preimpact failures or malfunctions. The airplane was equipped with a Ballistic Recovery Systems (BRS), and that system’s parachute and riser (lanyard) were not recovered following the accident. Examination of the BRS airframe system components revealed that the fire pin actuator was inside the rocket cone with the activation cable still attached, which was consistent with normal activation. Evidence indicated that the forward straps that connected to each front main spar, and the rear straps that were connected to the left and right attach plates on the rear bulkhead, remained connected to their respective bolts at the 3-point shackle. The 3-point shackle, which had separate attach points (bolts) for the forward and aft straps, and for the riser (lanyard) of the parachute, was located within the main wreckage. However, the riser for the airframe parachute was not attached to the 3-point shackle. The 3-point shackle bolt for the parachute riser was not visibly deformed. The other two bolts of the 3-point shackle that secured the forward and aft straps also did not exhibit any visible damage. Examination of a portion of the rear harness revealed that the shock absorption stitching pattern was not peeled/torn, indicating that there was no force applied to the rear harness at the 3-point shackle level. Based on this information, it is likely that the pilot activated the airframe parachute at some point during the accident sequence, the parachute bag properly deployed from its canister, and the forward harness straps opened from their stowed position; however, with the parachute riser not attached to the 3-point shackle, the BRS parachute would have been useless. Because the parachute and riser were not located, it could not be determined why the parachute riser, which last had maintenance performed nearly 6 years earlier, was not attached to the 3-point shackle. The pilot’s logbook was not located; therefore, the date of his last flight review and his instrument currency could not be determined. About 7 months before the accident, he last reported having accumulated 341 total hours of flight experience, of which 265 hours were in the accident airplane make and model. Toxicological testing results were positive for amphetamine, quetiapine, hydroxychloroquine, tadalafil, acetaminophen and ethanol. The FAA considers amphetamine and quetiapine as “Do Not Issue/Do Not Fly” medications. Whether the effects of the pilot’s use of amphetamine, quetiapine, hydroxychloroquine, or any associated underlying conditions contributed to the accident or affected his decision making could not be determined. Some or all of the small amount of detected ethanol could have been the result of postmortem production, and it is unlikely that ethanol effects contributed to the accident. In summary, the relatively low-time instrument pilot, who was flying while using multiple unapproved medications, flew into an area of a forecast convective weather that included precipitation and building cumuliform clouds in convective updrafts. These conditions were associated with a line of thunderstorms and severe to extreme turbulence, the latter of which by definition can render an airplane practically impossible to control. While flying well above the published maneuvering speed for the airplane’s weight, the airplane likely began descending with a corresponding airspeed increase, followed by an abrupt or full-control input that resulted in the in-flight breakup.

The accident pilot requested and received a standard preflight weather briefing package from ForeFlight at 1544 on May 6th. The weather briefing package contained all the standard weather forecast information valid at that time. Because the weather briefing was more than 18 hours before the intended departure, the weather data provided to the pilot did not include graphical forecast data. The pilot did not request a standard, updated or abbreviated briefing package from ForeFlight before departure on May 7th. Had he done so, forecast data and graphics would have been provided. The pilot also viewed airport information at 1301, 1313, 1429, and while in-flight at 1624 for his destination airport. Convective SIGMET 26E, which implied severe or greater turbulence, severe icing, and low-level windshear, was issued at 1755, or about 54 minutes before the accident, and it was valid until 1955. The Convective SIGMET was valid for VA, NC, TN, and KY and it reported an area of severe thunderstorms moving from 320° at 35 knots, with tops to Flight Level (FL) 410, hail to 1 inch, and wind gusts to 50 knots possible. High-Resolution Rapid Refresh (HRRR) modeling for the approximate accident site coordinates for 1900 hours local indicated that the wind at about 8,500 ft was from 270° at 16 knots. One witness near the accident site reported that about the time of the accident a varying wind gust from 168° to 340° occurred, with the gust from the south-southeast being described as “really hard.” Pilot reports indicated that severe turbulence was encountered in the area of the accident. One pilot, flying a Beech 350 airplane about 131 nautical miles west-northwest of the accident site in the same moving line of thunderstorms reported about 31 minutes after the accident encountering severe turbulence at 5,000 ft msl with ± 500 ft altitude change. Another pilot flying a Piper PA-46 airplane about 156 nautical miles west-northwest of the accident site in the same moving line of thunderstorms also submitted an urgent pilot report about an hour before the accident encountering extreme turbulence between 10,000 and 11,000 ft msl. There was no injury or damage reported by either pilot. FAA Aviation Weather Services Advisory Circular 00-45E defined moderate turbulence as causing changes in altitude and/or attitude but the aircraft remained in positive control at all times and usually caused variations in indicated airspeed. Severe turbulence was defined as large, abrupt changes in altitude and/or attitude causing large variations in indicated airspeed, with momentary times where the aircraft is out of control. Extreme turbulence was defined as the aircraft being violently tossed about and being practically impossible to control with possible structural damage. According to the pilot’s FAA airman records, on November 21, 2020, he received notification of disapproval of application for adding an instrument rating to his private pilot certificate. The notice indicated he would be re-examined on preflight procedures, air traffic control clearances and procedures, flight by reference to instruments, navigation systems, and instrument approach procedures. On December 15, 2020, he passed a check ride in the accident airplane, adding an instrument rating to his private pilot certificate. He reported having accumulated 270 total hours of flight experience and 49.5 hours of instrument flight experience on the application for the instrument rating. The pilot’s logbook was not located; therefore, the date of his last flight review and his instrument currency could not be determined. He reported to an insurance company having 341 total hours of flight experience and 265 hours of flight experience in the accident airplane make and model as of October 10, 2022. The airplane Type Certificate design was modified in December 2006 in accordance with (IAW) Supplemental Type Certificate (STC) SA01999CH by installation of a BRS-182 parachute recovery system. Review of the maintenance records indicated that on August 13, 2007, BRS, Inc., Service Bulletin 07-02 was accomplished by installation of kit part number 014125-01, pickup collar upgrade. On February 12, 2016, the BRS parachute was removed for a 10-year repacking., On August 24, 2017, the repacked BRS parachute was reinstalled, and the rocket and igniter were replaced. That same entry specified that the line cutter was due for replacement in August 2022. There was no record that the line cutter was replaced. By design, the BRS airframe parachute assembly was secured to the airframe by straps connected to both main spars at each wing root and also by straps connected to the left and right attach plates on the rear bulkhead. The front and rear harness straps were connected to separate bolts/bushings of a 3-point shackle assembly (3-point shackle). The riser (strap) of the parachute was connected to the third bolt/bushing of the 3-point shackle. The flight manual supplement associated with the BRS specified that deployment was approved by the FAA up to an airspeed of 135 knots, which matched a placard on the instrument panel. As part of the parachute repacking, the technician attached the parachute riser strap and the rear harness strap to separate attach points of the 3-point shackle; the work was confirmed and signed off by a quality assurance inspector. During installation of the parachute into the airplane after repacking, the front harness was the only harness required to be attached to the remaining separate bolt of the 3-point shackle. During the airplane’s last annual inspection, which was completed on September 1, 2022, the mechanic who signed off the inspection reported that he performed an inspection of the airframe parachute system using instructions provided by the airplane owner. He reported that the inspection was mostly visual, and he did not report any discrepancies with the system. The BRS system instructions for continued airworthiness (ICA) inspections specified external and internal inspections; however, the 3-point shackle was not specifically mentioned, and it could not be viewed during the external or internal inspection as part of the ICA. The airplane was equipped with an Avidyne EX500 multifunction display that was able to display weather radar images, datalink weather that included METARs, AIRMETs, and SIGMETs, and traffic and terrain information. The airplane was also equipped with a Sandel SN3500 electronic horizontal situation indicator (EHSI) that could display lightning and datalink weather. Both retained components were submitted to the NTSB’s Vehicle Recorder Laboratory for read-out. Data recovered from the Avidyne indicated that the weather receiver of the device was functional during the accident flight, but the recovered data did not contain any other pertinent information to the investigation. Each non-volatile memory chip of the EHSI was removed from the circuit board and read out and imaged successfully but further attempts to recover data from the chips were not performed. Weight calculations were performed using the airplane’s latest empty weight (1,894 pounds), the weight of useable fuel with full fuel tanks (528 pounds), the weight listed at the pilot’s last medical (185 pounds), the estimated weight of a duffle bag found in the wreckage (30 pounds), and subtracting the estimated fuel consumed (255 pounds) during the 2-hour-and-50-minute flight based on the flight plan fuel consumption of 15 gallons per hour. Thus, the estimated airplane weight at the time of the accident was about 2,382 pounds. According to the airplane Pilot’s Operating Handbook and FAA Approved Airplane Flight Manual, the published maneuvering speeds (no abrupt or full control movements) at 2,450 pounds were 100 knots indicated airspeed, or 99 knots calibrated airspeed. A postmortem examination of the pilot was performed by an Assistant Medical Examiner, Knox County, Knoxville, Tennessee. T