Airbus A319 132 N512NK accident near South Toledo Bend, Texas

Probable cause

an encounter with convective turbulence.

NTSB analysis

On May 20, 2017, about 1930 central daylight time, Spirit Airlines flight 330, an Airbus A319-132, N512NK, encountered turbulence while in cruise flight at flight level (FL) 360. Of the 146 passengers and crew onboard, one flight attendant received serious injuries. The airplane was not damaged. The regularly scheduled passenger flight was operating under the provisions of 14 Code of Federal Regulations Part 121 from Louis Armstrong New Orleans International Airport (KMSY), New Orleans, Louisiana, to Dallas/Fort Worth International Airport (KDFW), Dallas, Texas.

During cruise, as the flight was approaching a line of weather, the flight crew made a public address announcement for the passengers to be seated because they expected turbulence. In addition, the captain called the lead flight attendant (FA) and instructed that all the flight attendants be seated. The seatbelt sign was illuminated for the entire flight. About 10 minutes later, the flight penetrated a line of weather and the airplane had a short encounter with moderate turbulence. The autopilot did not disengage during the encounter.

When the turbulence occurred, one of the FAs was seated in the aft galley without her seatbelt fastened and was thrown upwards, hitting her head on the ceiling before landing on the galley floor. She was assisted by medically qualified passengers and remained on the floor for the remainder of the flight due to numbness in her extremities. Emergency personnel met the airplane after landing and the injured FA was transported to the hospital where she was diagnosed with number 1 lumbar fracture.

Text from the NTSB. Open the NTSB docket for DCA17CA123 for the full record.