American Airlines President Robert Isom said on Wednesday he sees growth opportunities in three higher-margin hubs where the U.S. carrier will be adding gates and flights over the next three years.

American "is going to focus" on the Dallas-Fort Worth, Charlotte and Washington, D.C. hubs, where its operations have a pre-tax margin of 13.1 percent, compared with the system average of 7.5 percent, Isom said at the Cowen and Company transportation conference.

American said recently it would scale back less profitable flights from Chicago to China.