The Transportation Department said Tuesday that it was launching an investigation into Delta Air Lines’ treatment of ... Regulators launched a similar probe of Southwest after its December ...

US Opens National Security Probe Into Imported Commercial Jets ... leased planes and deferring aircraft deliveries. Delta Air Lines is also unwilling to pay tariffs on aircraft deliveries.

Delta Air Lines is under investigation by the U.S. Department of Transportation's Office of Aviation Consumer Protection as the airline scraps hundreds of flights for a fifth straight day after a ...