The National Transportation Safety Board announced today that it is investigating the January 12 incident involving a Southwest Airlines 737-700 that landed at the wrong airport. Southwest Flight 4013, which was originally scheduled to land at Branson Airport in Missouri, landed at M. Graham Clark Downtown Airport instead, which is approximately six miles north of Branson. The aircraft landed safety at around 6:25pm CST and no one was hurt. The flight data recorder and cockpit voice recorder have been taken to Washington DC for readout and analysis. In addition, NTSB investigators will conduct interviews with the Southwest crew later this week.