US is investigating Delta's flight cancellations and faltering response to global tech outage

U.S. airline regulators have opened an investigation into Delta Air Lines, which is still struggling to restore operations on Tuesday, more than four full days after a faulty software update caused technological havoc worldwide and disrupted global air travel. Transportation Secretary Pete Buttigieg announced the Delta investigation on the X social media platform Tuesday morning “to ensure the airline is following the law and taking care of its passengers during continued widespread disruptions.” By midday Tuesday on the U.S. East Coast, Delta and its Delta Connection partners had canceled nearly 500 flights, or about two-thirds of all cancellations in the United States.