Passengers on a British Airways flight from London Heathrow to Washington, D.C., are reported to have been made to wait on the tarmac for about three hours after an emergency slide was activated shortly before the scheduled departure. The reported incident occurs “just seconds” before the flight was due to leave, and multiple accounts describe the activation as occurring due to staff error. Passengers remained on the aircraft while the situation is assessed and normal departure procedures are restored. The reports also cite an estimated cost of around £100,000, although the basis for that figure is not detailed in the provided accounts. No information is included in these sources about injuries or whether any evacuation took place. The incident is framed as a deployment of an emergency slide that triggers delay and operational complications ahead of the flight’s planned departure time.