Seven people have been taken to hospital after a Lufthansa flight was diverted to Washington Dulles International Airport following major turbulence.
Flight 469 was heading from Austin, Texas, to Frankfurt, Germany, but landed on Wednesday evening at the airport in Virginia.
Those taken to hospital had minor injuries, Metropolitan Washington Airports Authority spokesman Michael Cabbage said.
Plane forced to land in US after severe turbulence
Crew on the Airbus A330 reported severe turbulence at an altitude of about 11,300 metres while flying over Tennessee, said the Federal Aviation Administration, which is investigating the incident.
Twitter user Stryker Fadhel shared a picture he said was taken by his wife, who was on the flight.
"People who didn't have the seat belts fastened got hurt mostly cause it came as surprise without seat belt sign on and [lightning] hit the plane badly," Mr Fadhel wrote.
Passenger Susan Zimmerman, 34, of Austin, said one of the pilots told passengers the plane had fallen about 305 metres during the turbulence.
“It felt like the bottom just dropped out from underneath,” she told AP.
“Everything was floating up. For a moment, you are weightless.”
The brief but severe turbulence occurred about 90 minutes after take-off and led to the unscheduled landing as a precaution, Lufthansa said.
The airline's ground staff were working to passengers on other flights, it said.
"The safety and well-being of passengers and crew members is Lufthansa’s top priority at all times," the airline said.
Turbulence is essentially unstable air that moves in an unpredictable fashion.
Most people associate it with heavy storms, but the most dangerous type is clear-air turbulence, which can be hard to predict and often comes with no visible warning in the sky.
Turbulence continues to be a major cause of accidents and injuries during flights, a 2021 report by the US National Transportation Safety Board found.
Turbulence accounted for 37.6 per cent of all accidents on larger commercial airlines between 2009 and 2018, the report said.
