Ticker: AMR
YTD stock performance: -92%
Market cap: $220 million
Fortune 500 rank: 118

When it comes to poor performance, it's hard to top bankruptcy.

American Airlines parent AMR filed for Chapter 11 in November, after losing ground to competitors United Continental and Delta Airlines, which had already restructured in bankruptcy court.

Thomas Horton, the airline's newly appointed CEO, said American had tried to avoid bankruptcy. But the cost pressures had become "untenable," he added.

In addition to being at a competitive disadvantage, American was hurt by increased fuel prices, a loss of business travel customers and tough labor union negotiations.

American had been the world's largest airline as recently as 2006. But given the darkening economic outlook, the airline is not likely to survive as a `going concern' even after emerging from bankruptcy, according to Morningstar analyst Basilli Alukos.

American has the industry's "most exorbitant cost structure," Alukos wrote in a research report, citing the rise of low cost competitors, as well as declines in workforce productivity and flight hours due the company's aging fleet.

By CNNMoney's Ben Rooney and Fortune's Alex Konrad @FortuneMagazine - Last updated December 21 2011: 8:14 AM ET
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