Authorities said passengers on 43 American flights between 2018 and 2021 had to sit on the tarmac for more than three hours without being given a chance to deplane, violating federal rules that were put in place over a decade ago to prevent such waits. 

Transportation Secretary Pete Buttigieg said Monday the fine was part of the department’s push to hold airlines accountable for breaking rules meant to protect consumers. The department said earlier this year it is investigating a July 17 Delta Air Lines flight that was on the ground in Las Vegas for about three hours in the 111-degree heat before it was canceled.