US Airways was a major American airline headquartered in Tempe, Arizona, operating scheduled passenger and cargo services across the United States, Canada, Europe, the Caribbean, and Latin America. At its peak it was one of the largest airlines in the world by passenger traffic, tracing its roots back to All American Aviation, founded in 1937. The airline went through numerous mergers and rebranding phases over the decades, including acquisitions of Piedmont Airlines and PSA, before operating under the US Airways name from 1997. It filed for bankruptcy twice, in 2002 and 2004, before merging with America West Airlines in 2005. US Airways merged with American Airlines in December 2013, with the combined entity operating under the American Airlines brand. The US Airways name and brand were officially retired on October 17, 2015, when the last US Airways-coded flight operated.