The carrier said Friday it had apologized for causing customers distress after an emergency message was accidentally triggered.
Passengers were warned during a flight Tuesday that the Boeing 747 may crash into the sea. They heard the message: "This is an emergency. We may shortly need to make an emergency landing on water."
Michelle Lord, who was onboard, told Britain's The Sun tabloid that her fellow travelers were deeply frightened when the taped warning was played over the airliner address system.
"People were terrified. We all thought we were going to die," said Lord, 32.
British Airways said cabin crew quickly reassured passengers that the flight was not in danger. The company said it is investigating how the error happened.
"Our cabin crew immediately made an announcement following the message advising customers that it was played in error and that the flight would continue as normal," the airline said in a statement.