American has pared its flight network to the point that some corporate travelers have gone elsewhere, leaving the money- losing carrier unable to support most of its hub airports, one person said. That deficiency could be solved by combining American, the third-largest U.S. airline, with No. 5 US Airways, the people said.
http://www.bloomberg.com/news/2012-01-20/us-airways-said-to-consider-american-airlines-merger-to-fill-revenue-gap.html?cmpid=yhoo