Embraer E175 N204NN accident near South Lake Tahoe, California

Probable cause

The airplane's encounter with moderate turbulence during descent, which resulted in a serious injury to a flight attendant who was not securely seated. Contributing to the accident was the flight attendant's decision to continue to secure items before the flight crew made an announcement that it was safe to continue with the service activities.

NTSB analysis

The captain of the commercial air carrier flight reported that, during cruise flight, just before descent, he advised the cabin crew to finish the main cabin service activities and be seated for the remainder of the flight because it was expected to encounter turbulence. After completing the main cabin service, both flight attendants chose to continue securing items despite an initial encounter with turbulence because they did not feel endangered by it at the time. The turbulence stopped, and the aft flight attendant continued to secure drink containers. The airplane then encountered turbulence again, and the aft flight attendant sustained a broken ankle after being thrown in the air twice and landing hard. Several pilot reports and National Weather Service products reported moderate turbulence in the area at the time that the airplane encountered the turbulence.

The company flight attendant manual states that, during moderate or occasional severe and/or severe turbulence, flight attendants are to stop all services and leave carts with the brakes engaged until turbulence is reduced and to secure themselves in the nearest available seat. The company safety programs manager stated that pilots are responsible for notifying flight attendants of turbulence ahead of time if they are aware of it. After the conditions subside, the flight crew should make a public announcement to inform the flight attendants and passengers. If the aft flight attendant had been seated as instructed by the captain and not continued to secure drinks containers, she likely would have been seated at the time that the airplane encountered the moderate turbulence and not been injured. The aft flight attendant could have continued securing drink containers after the flight crew reported that the flight was clear of the turbulence and announced that it was safe to do so.

Text from the NTSB. Open the NTSB docket for WPR15LA239 for the full record.