ATA Airlines Inc. (ATAH), the nation's 10th-largest airline, filed for bankruptcy protection Tuesday, one day after naming an executive to oversee the restructuring of the discount carrier's mounting debt.

The filing under Chapter 11 (search) of the federal bankruptcy code came as the Indianapolis-based airline faces soaring fuel costs, an industry fare war and sharply lower demand for military charter flights.

ATA also is saddled with millions of dollars in debt from new aircraft purchases.

In recent weeks the company has announced plans to cut more than 300 jobs, including 150 flight attendants. So far this year, ATA pilots and flight attendants have accepted nearly $70 million in wage concessions.

In an SEC filing last week, ATA said its finances have worsened since Aug. 16, when it reported that it had lost $90.7 million during the first half of 2004.