American Airlines, a unit of AMR Corp , said its fourth-quarter mainline capacity will dip 3 percent due to an adjustment in its late fall and winter schedule and that it will retire up to 11 Boeing 757 aircraft in 2012.

The airline said the capacity reductions were aimed at coping with high fuel costs and an uncertain economy.

The company's Chief Commercial Officer Virasb Vahidi said the reductions were aimed at ensuring a reliable schedule for customers given anticipated pilot retirements in the fourth quarter.

American airlines said it expects full year mainline capacity to rise by 4 percent, from a year ago, and consolidated capacity to rise by about 1.2 percent.

(Reporting by Swetha Gopinath in Bangalore; Editing by Bob Burgdorfer)