What happened
On the flight from El Paso, Texas, to Chicago, Illinois, an American Airlines aircraft was cruising at FL330 approximately 30 miles north of Childress, Texas. While operating in instrument meteorological conditions (IMC), the aircraft encountered severe turbulence lasting for about five seconds.
At the time of the event, the First Officer was the pilot flying. Although no convective cells were appearing on the aircraft's radar in the immediate vicinity—with the nearest cell located approximately 20 miles to the right of the flight path—convective sigmets 99C, 01C, and 02C were active for the regions of New Mexico, Texas, Oklahoma, and Kansas.
During the turbulence, the seat belt sign was illuminated, all passengers were seated, and flight attendants were performing cabin service. Following the encounter, the flight crew notified Air Traffic Control (ATC) and diverted the aircraft to Oklahoma City, Oklahoma.
As a result of the turbulence, seven passengers and two flight attendants were transported to a local hospital for evaluation; all were subsequently treated and released. A post-flight inspection of the aircraft showed no damage, and the plane was returned to service.