Delta Airlines passengers line up for agent assistance at Hartsfield-Jackson Atlanta International Airport on July 22, 2024 in Atlanta, Georgia.The U.S. Department of Transportation's Office of Aviation Consumer Protection is investigating Delta Air Lines over chaos sparked by last week's global IT outage, according to a statement.The DOT cited widespread flight disruptions and customer service failures in which Delta did not uphold commitments to its passengers, it said. The agency also said the investigat ...