On September 16, 2005, America West Airlines and US Airways completed their merger. Although the corporate side and operationally, those companies merged, as of May 2008, the two flight operations have not been merged and Mesa continues to code share with the new US Airways Group as US Airways Express under its America West Express codeshare agreement. It operated CRJ200 and CRJ900 aircraft from hubs in Charlotte and Phoenix, and Dash 8 aircraft from its Phoenix hub until late 2011, when during Mesa's restructuring in bankruptcy, coinciding with United's cancelation of any further CRJ 200 service by Mesa, the CRJ 200's and Dash 8's were removed from service. By early 2012, the only airframe Mesa uses for the "west" side of US Airways out of its Phoenix hub and the "East" side out of its Charlotte hub is with the CRJ 900.