Merge two huge airlines like Atlanta-based Delta and Minnesota’s Northwest into one mega-airline, and a few things have to go on the old to-do list. You have to repaint hundreds of airplanes — a lot ...

Delta Air Lines has uncorked a rebranding of all of its fare types — upending the Basic Economy/Main Cabin/Comfort Plus/etc. order that has dominated the big U.S. airlines for the last decade or so.