Mergers have created a quartet of very large airlines. The four airlines, Delta, United, Southwest and American, now control 80 percent of the U.S. market. Here's when and how it happened.
2005. The US Airways-American West. The merger combined then No. 7 and No.8 airlines to create the USA's largest carrier.
2008. Delta merged with Northwest. The company took Delta's name in what became the largest U.S. airline deal ever.
2010. United and Continental merged, making Continental the largest U.S. Airline. Continental told its employees it was necessary to "make sure we remain a strong long-term competitor.'
2011. Southwest-AirTran. It took Southwest three years to fold AirTran operations into its own. The deal eliminated one of Southwest's leading low-cost rivals, say analysts reporting in USA Today.
2014. American-US Airways, the most recent merger restored American's status as the world's largest airline. It had slipped to No.3 and was at risk of being dwarfed by corporate contracts being offered by rivals Delta and Unted. U.S. Airways still needed help.
Seth Kaplan, editor of Airline Weekly, says this ends the round of mergers, partly because the government wouldn't approve any more.
