(From CBS News MoneyWatch) -- A source told CBS News that the boards of American Airlines and US Airways have approved a merger that would create the world's biggest carrier.
Under the deal, which is expected to be unveiled Thursday if the timeline isn't moved up sooner and there are no last-minute snags, the combined airline would keep the "American" name. It would still require federal approval, although that is virtually ensured. US Air CEO Doug Parker is expected to lead the combined company.
A merger of US Air and American would surpass a 2010 tie-up between United Airlines (UAL) and Continental and a 2008 deal joining Delta (DAL) and Northwest. The merged American would be the largest carrier and sport a market valuation of roughly $10 billion.
Although airlines tout such consolidation as a way to cut costs and expand service amid intense competition, whether industry mergers raise fares is an open question. Many analysts say yes because reduced competition in any business often results in higher prices. One study found that ticket prices went up more than 20 percent between Detroit and Atlanta after Delta bought Northwest. Fares went up more than 30 percent on routes between Chicago and Houston, as well as Newark to San Francisco, after the United-Continental deal.
In seeking to run more efficiently, merging airlines also often cut capacity and eliminate routes.
Other analysts are more optimistic about the potential benefits to travelers. They say the three largest U.S. airlines still must compete with discount carriers such as Southwest (LUV), which has flourished for years by offering low-cost flights and no-frills service.
The consolidation trend is largely blamed on the price of fuel. Oil now costs so much more per barrel than it did 10 years ago that one analyst says the margin of profit on many flights has shrunk to the value of a single seat. That means an airline can lose money if it flies with one single empty middle seat. The days of elbow room are over.
American Airlines has been operating under court supervision since declaring bankruptcy in November 2011.
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