From the article: Southwest hid signs of outdated technology that led to December failures, class action suit says

FILE – A Southwest Airlines jet arrives at Sky Harbor International Airport, Dec. 28, 2022, in Phoenix. With its flights now running on a roughly normal schedule, Southwest Airlines is turning its attention to luring back customers and repairing damage to a reputation for service after canceling 15,000 flights around Christmas. The disruptions started with a winter storm and snowballed when Southwest’s ancient crew-scheduling technology failed. (AP Photo/Matt York, File)