In a one-off incident in 2017, four passengers who had paid for a flight on United Airlines were selectively deplaned. One of the passengers, David Dao, saw excessive use of force against him as he was dragged out of the aircraft. The incident gained a lot of traction and brought a lot of bad press for United Airlines. But the event also brought a lesser-known aviation terminology – deadhead pilots (or deadheading employees) – into public discourse. The four passengers deplaned because the airline had to make room for these pilots.