Primary finding
Probable cause
The passenger's lack of compliance with the illuminated seatbelt sign, which resulted in her injury during a turbulence encounter.
Investigator assessment
Analysis narrative
According to the flight crew and a flight attendant, about 15 minutes after departure, the airplane was climbing through flight level 220. Although the captain had allowed the use of approved portable electronic devices (PED) as the airplane climbed above 10,000 feet, the fasten seatbelt sign remained illuminated. When the PED allowance was announced, a couple of passengers began to move about the cabin, including one that went to the lavatory. As the passenger was exiting the lavatory and returning to her seat, the airplane encountered unforecast moderate turbulence. The passenger fell down in the aisle and suffered a fractured ankle.
Source record
Factual narrative
According to the flight crew and a flight attendant, about 15 minutes after departure, the airplane was climbing through flight level 220. Although the captain allowed the use of approved portable electronic devices (PED) as the airplane climbed above 10,000 feet, the fasten seatbelt sign had remained illuminated for the climb. When the PED use was allowed, a couple of passengers began to move about the cabin, including one that went to the lavatory. As the passenger was exiting the lavatory and returning to her seat, the airplane encountered unforecast moderate turbulence. The passenger subsequently fell down in the aisle and suffered a fractured ankle. The flight returned to the departure airport.