Cessna T337 N922EJ accident near Longview, Texas

Probable cause

The noninstrument-rated pilot's improper decision to continue flight into convective weather conditions, which resulted in the airplane exceeding its maximum maneuvering speed and the subsequent in-flight breakup. Contributing to the accident was the pilot's inadequate preflight weather planning and his inadequate inflight weather avoidance of that weather.

NTSB analysis

The non-instrument-rated private pilot and three passengers departed on a cross-country flight in a multi-engine airplane, even though the pilot did not hold multiengine rating. At the time of departure, the weather was reported to be clear. However, a line of thunderstorms and high winds were along the flight route. Radar data showed that the airplane initially flew eastward and that, after entering an area of convective weather, it turned westward, likely to avoid the area of weather. The airplane then flew northeast before resuming eastward flight and entering another area of weather. The airplane then entered a series of descending spiral turns until impact. About 10 hours after the accident, a witness noted wreckage near a roadway, and the airplane was located shortly thereafter.

No preimpact anomalies were found with the airframe or engines that would have precluded normal operation of the airplane. All separations were consistent with overload.

Parts of the right wing were located between 1 and 3 nautical miles from the main wreckage, indicating that an in-flight breakup of the airplane had occurred. Radar data showed that the airplane was flying at a groundspeed of between 160 and 190 kts before it entered the spiral shaped flight track. According to the manufacturer, the airplane's maximum maneuvering speed was about 135 kts. Thus, the in-flight breakup occurred because the airplane was operating above its maximum maneuvering speed, which exceeded the design load factor of the airplane.

Various aviation weather products indicated that the airplane entered areas of significant convective weather twice. Once the airplane entered the clouds and precipitation associated with thunderstorms, the airplane was also in areas that were favorable for icing conditions. No evidence indicated that the pilot received a weather briefing on the day before or the day of the accident. If he had received a weather briefing, he could have been aware of the severe thunderstorms predicted for the flight route.

Toxicology testing showed the pilot had taken a beta blocker used in the treatment of hypertension and certain arrhythmias.

Text from the NTSB. Open the NTSB docket for CEN19FA094 for the full record.