American Airlines McDonnell Douglas MD-82 accident

The MD-82 encountered turbulence in the vicinity of Charlotte, North Carolina, and one passenger received serious injuries. The captain stated that the ride had been smooth, and there had been occasional light chop. He further stated that the seat belt sign was off, and approximately 7 people were standing at the time of the incident, including the three flight attendants. He said the flight was at FL310, in night visual meteorological conditions, with stars and ground lights visible, and that radar showed a clear flight path, with a significant line of storms approximately 30 miles east of their course. According to the captain, about 2207,the airplane entered instrument meteorological conditions and quickly encountered moderate chop, followed by a very sharp jolt. He said he had immediately turned on the fasten seatbelt sign after the first jolt, and they then received two more sharp jolts. He said that rain and Saint Elmo's were present, and he turned the airplane to the right, back towards where they had last seen ground lights and then informed FAA Air Traffic Control Jacksonville Center of the turn and ride condition. In about 30 seconds, he said the ride became smooth with some light chop, and they entered visual meteorological conditions again. The NTSB examined radar and weather data pertinent to the flight, and the data revealed that when the accident airplane's flight path for the period of the flight was overlaid with infrared satellite imagery, about 2145, there was an isolated thunderstorm with an estimated cloud top of about 36,000 feet in the vicinity of GLOVR intersection. In addition, additional data at 2202, and 2215, showed that the thunderstorm cloud tops had gotten higher, and the thunderstorms had expanded outward and moved northeast along the airplane's track. Digital Doppler weather radar data for Greer, South Carolina, when evaluated with respect to the turbulence times, showed reflectivity echoes in the vicinity of the turbulence location, and the reflectivity’s varied from VIP level 1 (very light) to VIP level 5 (intense). Reflectivity cross sections of radar data along the flight track showed the maximum radar tops which the flight penetrated to be about 40,000 feet. Examination of the airplane's Flight Data Recorder provided data that showed altitude changes, and fluctuations in vertical and lateral acceleration, consistent with other information. Both the NTSB Meteorological, and Flight Data Recorder Factual Group Chairman's reports, have added as attachments.

Verbatim NTSB analysis and probable cause from the NTSB dataset