Updated

Those airline fees fliers pay to change reservations and check-in baggage really add up. According to data compiled by the U.S. Department of Transportation, fees charged in 2010 brought in $5.7 billion in revenue.

The fees were introduced in 2008 to offset increasing fuel costs and the downturn in the economy. An industry trade group, the Air Transport Association, says the fees made it possible for the struggling industry to turn a profit.

Baggage fees are especially lucrative, bringing in $3.4 billion. Most U.S. carriers charge $25 for the first checked bag and an additional fee for a second bag. Delta Air Lines raised the most money from baggage fees, generating $952 million in revenue. Newly merged Continental and United brought in $655 million, followed by $580 million for American Airlines.

Fees from changes in reservations generated $2.3 billion, down 3.2 percent from the previous year. Delta brought in the most cancellation revenue, followed by American Airlines. Depending on the airline, fliers can pay up to $250 to change their travel plans. Some airlines set fees based on distance traveled and the class of service.

According to the Air Transport Association, the additional fees will not be going away anytime soon. But there is some good news for fliers. Starting this summer, new federal rules will require airlines to make it easier for customers to figure out fees. Airline web sites will have to post fees on a single page and airline agents will have to quote prices that include fees and taxes. George Hobica of the low fare website, Airfarewatchdog says the new regulations should make it easier for customers to shop around.

Despite the fees, the airline industry says adjusted for inflation, it is cheaper to fly today than during the 1970s. But many fliers still feel nickel and dimed. In addition to baggage and change fees, fliers are also paying for priority seating, meals and the cost of entertainment.

It ain’t peanuts. But most airlines stopped giving those away for free a long time ago.