If North American airline bankruptcy protection filings in the 21st century continue their pattern, then American is likely to be operating under Chapter 11 rules for an 18-month to two-year period.
A quick bankruptcy protection file history:
US Airways: Aug. 2002 - Mar. 2003 (emerging after just seven months and after an Air Transportation Stabilization Board loan); then also Sept. 2004 - Sept. 2005.
United: Dec. 2002 - Feb. 2006 (the longest at some 37 months)
Air Canada: Apr. 2003 - Sept. 2004
Delta: Sept. 2005 - Apr. 2007
Northwest: Sept. 2005 - May 2007