All the major corps are playing the same game. Money is cheap right now therefore issue debt at staggering and alarming rates no matter the quality of the debt. The second leg of this stool is stock buybacks to goose earnings. Using profits to buyback its own stock to reduce the number of outstanding shares artificially increases quarterly earnings. It's where we are in the business cycle.
When a recession comes AA and all the other corps not just airlines will begin the belt tightening and the debt issuance and stock buybacks wont be in favor by wall st and it's analysts anymore.