According to the agency, the airline flew hundreds of thousands of passengers in the planes from June 2006 to March 2007 without complying with a September 2004 safety directive to inspect for fuselage cracks. After advising the FAA of its mistake, the airline received verbal approval from the local FAA Dallas office to keep operating the aircraft, and the FAA said in a press release that the carrier flew an additional 1,451 flights before completing the inspections.
The FAA said the size of the penalty "reflects the serious nature of those deliberate violations." Southwest has 30 days to appeal.