11. Delta Air Lines Inc; $21.8 billion
Based and headquartered in Atlanta, Georgia, Delta operates an expansive domestic and international network, spanning North America, South America, Europe, Asia, Africa, the Middle East and the Caribbean.
In 2004, in an effort to avoid bankruptcy, Delta announced a restructuring of the company that included job cuts, and an aggressive expansion of Atlanta operations by some 100 new flights. This was known to all Delta employees as 'Operation Clockwork'.
Further, by mid-2004 the airline announced it would be closing its fourth busiest hub (Dallas-Fort Worth International Airport). In a huge concessionary move, the pilots at Delta agreed to across-the-board 32.5 per cent reductions in hourly pay rates in order to help the company stave off a bankruptcy filing.
On September 14, 2005, Delta filed for Chapter 11 bankruptcy protection for the first time in its 76-year history. The company cited high labour costs and record-breaking jet fuel prices as factors in its filing.
At the time of the filing, Delta had $20.5 billion in debt, $10 billion of which accumulated since January 2001.
On April 30, 2007, Delta Air Lines emerged from bankruptcy protection as an independent carrier.
Image: Delta Airlines jets are prepared for flight at the Cincinnati/Northern Kentucky International Airport | Photograph: Scott Olson/Getty Images
Also read: India's 10 cities with highest household incomes