Created Wednesday, Jun 9th 2021 13:06Z, last updated Wednesday, Jun 9th 2021 13:06Z
A Skywest Airlines Canadair CRJ-700 on behalf of American Airlines, registration N745SK performing flight OO-3167/AA-3167 from Atlanta,GA to Chicago O'Hare,IL (USA) with 74 people on board, was enroute at FL360 about 120nm south of Saint Louis,MO (USA) when the crew decided to divert to Saint Louis reporting a flight attendant had sustained a head injury as result of turbulence. The aircraft landed safely in Saint Louis about 25 minutes later.
The FAA reported one flight attendant received injuries as result of turbulence enroute, the severity of the injuries is still being assessed.
The airline reported a flight attendant and two passengers were taken to a hospital for evaluation after the aircraft had encountered severe turbulence enroute.
The occurrence aircraft departed Saint Louis after about 2.5 hours on the ground and reached Chicago as flight OO-9851 with a delay of 3:15 hours.
On Mar 10th 2018 the NTSB released preliminary information indicating that one passenger received serious, two flight attendants and eight passengers received minor injuries in the turbulence encounter. The aircraft had been enroute at FL360 and maneouvering to avoid adverse weather.
On Jun 9th 2021 the NTSB released their final report concluding the probable cause of the accident was:
An encounter with convective turbulence while maneuvering to avoid conflicting traffic.
The NTSB analysed:
While in cruise flight around 36,000 ft, the flight crew of the scheduled domestic passenger flight was instructed by air traffic control to turn for traffic separation. The crew reported that, after completing the turn, the airplane entered a cloud and encountered severe turbulence. The seat belt sign was not activated at the time of the encounter, and of the 74 passengers and crew members aboard, one passenger received serious injuries and two flight attendants and eight passengers received minor injuries. The airplane was not damaged.
According to flight data recorder information, during the encounter, vertical acceleration ranged from - 0.8g to 1.89g, the airplane lost about 200 ft altitude in 2 seconds, and the airspeed varied by about 15 knots. The airplane entered an 11.6° nose-down pitch attitude and rolled 26 degrees to the left. The crew reported that the flight until the encounter had been smooth. They reported that they could see the cloud build-up as they were approaching it from about 80 to 100 miles away, but that their radar did not indicate that they were going to encounter convective weather.
The company's flight operations manual stated that, before entering an area of thunderstorms, pilots were required to ensure that all personnel were seated and safety belts were fastened.
Infrared Satellite Image GOES-E at 23:45z about 80 minutes after the turbulence encounter (Graphics: AVH/NASA):