Some passengers were hurled to the ceiling Monday when an Aeroflot flight from Moscow to Bangkok hit a patch of turbulence so severe that dozens of passengers were injured. The Boeing 777 hit what's known as "clear air turbulence" around 40 minutes before landing in Bangkok, where 27 passengers were hospitalized, some with broken bones, the Guardian reports. The airline is paying for their treatment, though it says the injuries were definitely not its fault. "The reasons behind the injures were that some of the passengers had not had their seatbelts fastened," Aeroflot said in a statement. Passenger Rostik Rusev tells CNN that it lasted for 10 terrifying seconds.
"There was blood on the ceiling, people with broken noses, babies who were hurt. It was horrible. It came out of nowhere. It was like driving a car and a tire suddenly bursts," Rusev says, adding: "The aircraft personnel couldn't have been more professional and courageous. They were heroes in everything they were doing." There are hundreds of cases every year—usually milder ones—of aircraft encountering clear air turbulence, which is caused when masses of air moving at different speeds meet, the BBC reports. Pilots rely on each other to report turbulence pockets they encounter in skies that appear clear and calm.