A British Airways crew member on her debut flight mistakenly activated the emergency slide as the plane taxied to the runway.

The error cost the airline £50,000 and delayed passengers on the Airbus 350 for more than five hours on Sunday (11 June) afternoon.

The plane had just pushed back from the stand at Heathrow and was moments from take-off to Austin, Texas, when the mistake happened, The Sun reports.

Emergency services rushed to Terminal 5 and surrounded flight BA191 after the slide had been deployed.

The plane had to be replaced and a new emergency slide was found for the original aircraft.

BA bosses have reportedly ordered the cabin crew member back to training which is the same course of action for anyone who ‘blows’ a slide at the airline.

BA said: “The aircraft returned to the stand and customers disembarked normally. We arranged a replacement aircraft for them to continue their journey the same day and have apologised for the inconvenience caused.”

The incident comes five months after another British Airways steward activated the emergency slide in an error that cost the airline £50,000 when a new crew member triggered an evacuation procedure by opening an escape door on a flight that was preparing to take off from Heathrow to Lagos.