For about nine hours, Sead Nikaj’s flight back home to New York from Istanbul was smooth.

But as the plane was crossing over Maine on Saturday, it hit a patch of severe turbulence, he said. Mr. Nikaj said he watched the woman next to him fly out of her seat. Oxygen masks dropped from the ceiling. People banged their heads, screamed and prayed.

For about 10 to 15 minutes — but what felt like an eternity to Mr. Nikaj — he thought he was going to die.

“I said, ‘God help me,’” he said.

The Turkish Airlines plane landed safely at Kennedy Airport, but at least 30 people were taken to hospitals with non-life-threatening injuries because of the turbulence, the authorities said.

One flight attendant broke her leg, said Steve Coleman, a spokesman for the Port Authority of New York and New Jersey. The rest of the injuries were minor, and included “bumps, bruises and cuts,” Mr. Coleman said.