U.S. airlines are earning billions, and they're collecting more in fees on checked bags and reservation changes. Whether airlines are making more or less money than before depends on which figures you use. The Department of Transportation said Monday that airlines collected $3.5 billion in bag fees last year, a 5 percent increase over 2013, and $3 billion in reservation-change fees, a 6 percent hike. Fees began escalating in 2008, when airlines were losing money and facing a sharp rise in fuel prices.Read more on NewsOK.com