Think your flight's crowded now? American Airlines says it expects to squeeze more seats into the coach sections on many of its planes.

The plans were disclosed in a statement from Lauri Curtis, the airline's vice president of flight services, to the airline's flight attendants. The additional seats will mean that the flights will be required by law to have an additional flight attendant on board each flight.

"We expect to add seats to the 737 and MD-80 fleets, but we haven't yet determined the right number of seats," she wrote. The airline is looking for ways to increase revenue after its merger with US Airways.