Big announcement from American Airlines (AA) and US Airways (US) over how they’d be handling their mandated slot sell off at New York’s LaGuardia (LGA) and Washington’ Reagan National (DCA) airports.

At LGA, effective April 1, AA+US are losing 12 sets of slots: Was expecting relatively minor changes, but that’s not what’s happening. The combined carriers will eliminate all nonstop flights from LGA to Atlanta (currently 8 daily), Cleveland (3), and Minneapolis (4) while adding nonstops to Charlottesville, Va., Little Rock, Ark., Roanoke, Va., Dayton, Ohio, Louisville, Ky., Wilmington, N.C., Greensboro, N.C., Norfolk, Va., Knoxville, Tenn., and Richmond, Va.

The exact schedule isn’t out yet but I would also expect some reduction in flights between CLT and LGA. The combined total is 17 flights a day with some on regional jets, which would be an easy cut.

Analysis: Interest. Essentially dropping what must be underperforming routes to major cities while adding flights to cities in which US Airways is strong. This adds back some of the small city to LGA service that US Airways had to give up as a condition of the US Airways/Delta LGA/DCA slot swap.

At DCA, where AA+US are losing 44 sets of slots, the combined carrier will be eliminating nonstops at a date to be determined to 17 cities in the future. They are: Augusta, Ga. (currently 1 flight a day); Detroit (5); Fayetteville, N.C. (1); Fort Walton Beach, Fla. (1); Islip, N.Y. (2); Jacksonville, N.C. (1); Little Rock, Ark. (1), Minneapolis (3); Montreal (2) Myrtle Beach, S.C. (not currently flown); Nassau, Bahamas (1); Omaha, Neb. (1); Pensacola, Fla. (1); San Diego (1); Savannah, Ga. (3); Tallahassee, Fla. (1); and Wilmington, N.C. (1). That’s 25 flights a day plus San Diego. DCA has a 1,250 mile limit for nonstop service but US Airways and American each have a single wildcard exception. American uses its exemption to fly to Los Angeles while US Airways serves San Diego. What’s happening is that the DCA – San Diego flight is getting to Los Angeles, so that the combined carrier will have two flights day on that route (Los Angeles is one of AA’s hubs.)

Analysis: This wasn’t unexpected. Some of the passengers that were connecting in DCA will now have to do so in Charlotte or Philadelphia — the exact mix is uncertain.

More whenever the exact schedules are posted.