American Airlines filed the largest airline Ch.11 in 2011 and merged with US Airways

American Airlines was founded in 1930 through the merger of more than 80 small airlines, growing into one of the world's largest carriers. Its parent company, AMR Corporation, was formed in 1982. By 2011, American was the third-largest US airline by revenue, with hubs at Dallas/Fort Worth, Chicago O'Hare, Miami, and New York JFK, and a fleet of over 600 aircraft serving 260+ destinations.

American had not been profitable since 2007, posting cumulative losses of $11 billion from 2001 to 2011. The airline carried the highest labor costs among its peers — legacy union contracts from before its competitors' bankruptcies gave Delta, United, and US Airways cost advantages. With fuel prices rising and revenue stagnant, AMR was burning cash. American had avoided bankruptcy while Delta, Northwest, United, and US Airways all restructured, but its costs were no longer competitive.

On November 29, 2011, AMR Corporation filed for Chapter 11 in New York. The filing listed $23.51 billion in assets and $29.6 billion in debt. CEO Gerard Arpey, who had resisted bankruptcy for years, stepped down and was replaced by Thomas W. Horton. The airline continued operating while restructuring. In February 2012, it announced 13,000 job cuts — 18% of its 73,800 employees — and eliminated management layers. New aircraft orders were placed: 260 Airbus A320neos and 200 Boeing 737s.

In February 2013, AMR announced a merger with US Airways valued at $11 billion. AMR bondholders received 72% of the new company while US Airways shareholders got 28%. The DOJ sued to block the merger in August 2013, settling in November after American agreed to divest slots at Reagan National and LaGuardia. The merger closed on December 9, 2013, forming American Airlines Group with Doug Parker as CEO. Creditors were paid in full; former stockholders received just 3.5% of the new equity.