A 1.1 percent decrease in combined consolidated traffic in February and a consolidated capacity decrease of 1.8 percent forced the planned reductions.

The planned capacity reduction will be achieved canceling flights in certain markets and reducing flight frequencies. The changes will force a 5 percent decrease of consolidated domestic capacity and a 2 percent international decrease in the fourth quarter.

"The company now expects its full-year 2011 consolidated capacity to be roughly flat year-over-year," United Continental Holdings said in a statement. "The company now expects full-year 2011 international capacity to be up 2.5 to 3.5 percent, and full-year 2011 domestic capacity to be down 1.5 to 2.5 percent year-over-year."

United will also save money on fuel by removing less fuel-efficient plants from its fleet.

While passenger numbers have taken a hit recently, in February, cargo revenue tonne miles were up 3.3 percent year-over-year.