Southwest is planning a new route from Washington Reagan National to St. Louis, using slots it has purchased from discount competitor Spirit Airlines.
Southwest is awaiting a green light from the Transportation Department to use the slots beginning Sept. 6, the day that Spirit transfers its Washington-Fort Lauderdale service to nearby Baltimore-Washington.
Spirit has four slots at National, enough for two daily roundtrip flights.
Spirit’s move to Baltimore, a Southwest stronghold, coincides with the launch of nonstops from Baltimore to Dallas Fort-Worth,
where the carrier has been expanding.