Good times are finally back for the nation's airlines. For travelers, that means it's getting harder to find bargains.

The summer travel season got off to a roaring start, fares are up, and money is rolling in from fees on things like checked baggage.

The six biggest U.S. airlines earned about $1.3 billion in the second quarter, and more profits are expected for the rest of the year. Even so, airlines are still woozy from the one-two punch of record-high fuel prices followed by a recession. Those six big carriers lost $22.7 billion in 2008 and 2009. And that's just a portion of the $63.35 billion that U.S. passenger airlines lost from 2001 to 2009, according to the Transportation Department.

There were plenty of fare sales when the airlines were struggling to fill seats. Now those seats are in demand, so deals are less common. And travelers are paying for "extras" such as an aisle seat, checking bags and buying a ticket over the phone -- things that used to be part of the fare.

Here's what travelers can expect in the months ahead:

Fares and fees: The airlines are hooked on fees after two years of using them to overcome, first, high fuel prices and then slumping travel demand. A new study shows that worldwide, carriers took in $13.5 billion from fees in 2009, a 43 percent jump in just one year.

Airlines have boosted ticket prices too. Summer fares are up an average of 18 percent, according to figures from a trade group for the big airlines.

Packed planes: Including regional flights, Delta Air Lines filled 88 percent of its seats in June, Continental sold 87 percent, and American 86 percent -- that's about 2 percentage points higher than last summer.

"Leisure demand has been strong, and we expect it will remain so throughout the remainder of the summer," Continental CEO Jeff Smisek said.

Labor: Several large U.S. airlines are in labor negotiations that could lead to higher costs and even disruptions. The most acute problems are at American, where flight attendants and some ground workers are talking openly about possible strikes this fall. Delta faces unionization votes by flight attendants and ground workers.