What happened
While approximately 38 miles from the destination airport, the captain instructed the flight attendant to be seated due to the potential for turbulence. Following the completion of the approach checklist, the flight attendant was signaled to begin the final cabin check.
As the aircraft reached 9 miles from the airport, it encountered a single strong windshear. The force of this encounter caused the flight attendant to be thrown against the ceiling and subsequently onto the floor. At the time of the incident, the aircraft was operating within a weak Level I weather radar return, within 6 miles of a Level II return, and within 9 miles of a very strong Level IV return.
Findings
The investigation noted discrepancies in operational procedures regarding cabin crew safety. According to the operator's flight operations manual, the captain is responsible for advising the flight attendant whether they should remain seated with their seat belt fastened. However, the investigation found that neither the flight operations manual nor the flight attendant manual provided instructions on when the crew member should resume duties after being instructed to sit. Additionally, there were no instructions requiring the captain to notify the flight attendant when it was safe to resume cabin duties.