Incident Overview
Approximately 15 minutes after departure, while the aircraft was climbing through flight level 220 (FL220), the captain permitted the use of approved portable electronic devices (PEDs). However, the fasten seatbelt sign remained illuminated throughout the climb. Following the authorization, several passengers began moving about the cabin, including one individual who proceeded to the lavatory.
Sequence of Events
As the passenger was exiting the lavatory and returning to her seat, the aircraft encountered unforecast moderate turbulence. The passenger subsequently lost her balance and fell to the aisle floor, sustaining a fractured ankle as a result of the fall.
Aftermath
In response to the injury, the flight crew decided to return the aircraft to the departure airport. No further details regarding the flight's return or medical treatment were provided in the source.
Operational Context
According to the flight crew and a flight attendant, the turbulence was not forecasted. The decision to allow PED use above 10,000 feet was in accordance with approved procedures, but the seatbelt sign remained on as the aircraft continued its climb.