Event Description
A flight experienced light chop while in cruise flight at Flight Level 330 (FL330). In response, the flight crew activated the seatbelt sign. A few minutes later, the aircraft encountered moderate clear-air turbulence. The captain noted that there were no radar returns within 20 miles, and beyond that, only green returns were visible.
When the initial chop was encountered, the flight crew made an announcement over the public address system directing flight attendants to be seated. At the time of the moderate turbulence encounter, one flight attendant was entering the top crew rest bunk located on the aft wall for a rest period.
Injury Details
The flight attendant's balance was compromised because she did not have both feet on the ground while entering the bunk. When the airplane encountered the turbulence, she fell forward toward the wall. She extended her right hand for protection but lost her balance and fell to the cabin floor, sustaining a serious injury.
Aircraft Condition
The aircraft did not incur any damage during the event.