Airlines cancel more than 3,000 U.S. flights amid storm, Delta slide evacuation at Atlanta * Airlines canceled more than 3,000 U.S. flights while more than 3,000 more were delayed. * A massive winter storm snarled travel across the Southern U.S. * A Delta flight aborted takeoff and evacuated passengers via slides at Atlanta’s airport, further disrupting operations. * Delta, Southwest, American and other carriers waived change fees and fare differences because of the storms and severe weather