The National Transportation Safety Board (NTSB) issued a preliminary report Wednesday detailing its probe of a Delta Air Lines flight that experienced “severe” turbulence in late July, sending more than a dozen people to the hospital.

The safety board said Delta Flight 56, en route from Salt Lake City to Amsterdam, encountered the significant turbulence on July 30 while flying over Creston, Wyo. After injuries were reported, the flight crew diverted to Minneapolis-St. Paul International Airport, according to officials.

“After landing, 24 of the 246 passengers were evaluated by emergency medical technicians, with 18 transported to local hospitals for additional assessment; information regarding their conditions is currently unavailable,” the report reads.

During the flight, NTSB noted, the plane at one point reached well above maximum operating speed and lifted the aircraft about 10,000 feet in nearly 20 seconds. The plane then “rapidly” dipped 25,000 feet, per the agency.

“A climb/descent cycle repeated about three times over a two- to three-minute period, which resulted in the airplane re-entering a cloud layer,” the report reads.

Flight safety has made headlines in recent months following high-profile incidents such as the Alaska Airlines flight that lost its door plug mid-air in January 2024 and the crash earlier this year between an Army Black Hawk helicopter and an American Airlines passenger flight near Reagan Washington National Airport that killed more than 60 people.

“Delta continues to fully support the ongoing NTSB investigation and out of respect for that process, we will decline additional comment,” Delta Air Lines spokesperson Morgan Durrant said in an email to The Hill on Wednesday.