Incident Summary
The incident occurred while the aircraft was cruising at Flight Level 330 in visual meteorological conditions. No Significant Meteorological Information (SIGMET) advisories for turbulence were in effect at the time. The seatbelt sign was illuminated throughout the event.
Sequence of Events
According to data from the flight data recorder, the turbulence consisted of two distinct pulses separated by an interval of 8 seconds. Each pulse registered a maximum vertical acceleration of +1.6 g on the aircraft's vertical axis. At the time of the encounter, flight attendants were working in both the forward and aft galleys, preparing for meal service.
Injuries
As a result of the turbulence, three flight attendants sustained minor injuries. A fourth flight attendant suffered a serious injury, specifically a fractured ankle. Additionally, two passengers seated in the rear of the aircraft, whose seat belts were unfastened, received minor injuries.