10. UAL Corp; $25.2 billion
UAL Corporation is an airline holding company, incorporated in Delaware with headquarters in Chicago, Illinois. The CEO of UAL Corporation since September 2002 is Glenn Tilton.
The promise of continued success in the new millennium quickly evaporated as the 'perfect storm' began to develop in 2000.
An economic downturn of global proportions, protracted labour negotiations, a proposed merger with US Airways and the tragedy of September 11, 2001, hit United hard.
For the year 2001, the company suffered a record loss of $2.1 billion. By mid-2002, United was asking employees to make wage concessions and asking the US government for a loan to help the company back to financial stability.
By early December, the company had reached agreements with most of its unions for wage reductions, but its loan application was rejected on December 4.
On December 9, 2002, UAL Corp filed for Chapter 11 bankruptcy. The company quickly received debtor-in-possession financing to allow it to continue 'business as usual' while it reorganized its debt, capital and cost structures. It came out of bankruptcy on February 1, 2006.
Image: A United Airlines jet takes off from Denver International Airport | Photograph: Kevin Moloney/Getty Images
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