Delta Air Lines is on the move at BWI-Marshall Airport, the latest in a series of changes as the airport prepares for an expansion project in 2012.

Beginning next week, Delta will shift its operations from Concourse C to Concourse D.

As you may remember, AirTran was most recently based at Concourse D but last month it shifted to be closer to owner Southwest Airlines in the A/B Concourse.

Yes, it's musical chairs, folks. With a little alphabet soup thrown in. But when the music stops sometime in 2013, BWI expects to have created a more passenger-friendly airport that's easier to navigate.

To that end, starting Tuesday, Dec. 13, all Delta flights will operate from gates on Concourse D and ticketing and baggage check-in will take place in the ticket lobby near Concourse D. Arriving baggage for Delta customers will utilize baggage carousel number 14, located on the lower level of the airport.

The moves will make way for BWI's $100 million terminal expansion and renovation project, which will include construction of a new security checkpoint - the airport's largest - in Delta's old space.