AA and US Air merger

American Airlines and US Airways finalized their merger deal on Dec. 9, becoming the world’s biggest airline. Under the name American Airlines, it will offer 6,700 flights daily to 330 destinations in 50-plus countries.

US Airways’ shuttles may operate under the old name for up to two years, as it will take many months to merge the airlines’ booking and code-sharing systems and sort out routes and terminals. However, the frequent-flyer programs were expected to be merged in January, with members retaining flyer miles from both airlines.