I was looking at the US Airways  annual report its K form and the lengthy company description lists Las Vegas as a secondary hub like Pittsburgh not a primary hub  The link for the annual report is httplibrarycorporateirnetlibraryitemsAnnualReportpdf and the appropriate quote is found on page  of the pdf file  The quote is The Company has primary hubs in Charlotte Philadelphia and Phoenix and secondary hubsfocus cities in Pittsburgh Las Vegas New York Washington DC and Boston  I made this change on the article page