With four grandchildren in Washington, D.C., Melinda Mitchell has plenty of reasons to visit the nation's capital.

The Battle Creek resident makes the trip about every other month, so she knows how to find a cheap flight.

"The best deal, money-wise, is probably Southwest, but for convenience, there's Sun Country out of Lansing," Mitchell said.

Flying on Southwest out of Detroit means a longer drive and paying for parking, but Mitchell noted that the airline doesn't charge a fee for her checked baggage.

And for her, Lansing and Detroit are still cheaper than the Kalamazoo/Battle Creek International Airport only 30 minutes away. The only time Mitchell said she'd flown out of Kalamazoo was when she got a cheap ticket airline.

Travel agent Sandra Dunn has had similar experiences while filling requests for cheap ticket airline.

"When they want to go out of Kalamazoo, we just ask them if it's OK if we go ahead and check the different airports," said Dunn, owner of Dunn's Destinations in Marshall.

The wider search often ends up saving her clients money. That's because Kalamazoo/Battle Creek International Airport tends to have some of the most expensive airfares in the area. In fact, in an April New York Times analysis, blogger Nate Silver ranked the Kalamazoo airport as the fourth-most overpriced small airport in the country.

Government figures on cheap ticket airline prices confirm what many local frequent flyers already know: A cheaper flight usually means first driving farther from home.

Data compiled by the U.S. Department of Transporation's Office of Aviation Analysis showed that average one-way airfares from Kalamazoo/Battle Creek International Airport to various U.S. cities during the fourth quarter of 2010 (the most recent figures available) was concistently the highest when compared to flights out of other Michigan airports or Chicago. The difference between Kalamazoo and the cheapest airport was as much as $154.

While Kalamazoo had the highest average cheap ticket airline price for each destination, cheap ticket airline were found coming out of Detroit, Grand Rapids or Chicago. For Chicago, the average is for flights out of both Midway Airport and O'Hare International.

The rankings did not surprise Cliff Monshoginis, director of the Kalamazoo/Battle Creek International Airport.

"We don't like it either," he said. "We don't have any influence on setting airfares."

Since airlines determine their cheap ticket airline, Monshoginis said the airport can only make an effort to attract more airlines and drive down prices through competition and by keeping operational costs low.

Along with major carriers Delta and American Eagle, the discount airline DirectAir offers flights to Florida out of Kalamazoo.

"Fares are determined by a wide variety of factors, including the type of aircraft used to fly the route, the cost of jet fuel, the size of the market, airport costs, the time of year, the amount of time prior to the travel dates, and overall customer demand in the market," said Delta spokesman Trebor Banstetter in an emailed statement.

But other aspects come into play, said Ed Martelle, spokesman for American Eagle. The cost of the lease on an airport, the cost of fuel at that airport and passenger facility charges are all examples of expenses that are out of the airline's control, he said.

The size of an airport and the surrounding population it serves are major factors in determining cheap ticket airline prices, said Han Kim, a professor at the University of Michigan business school who has studied the airline industry.

"When there's no competition, they really drive up the prices," Kim said. "But then it also depends on the demand and the local population. Obviously, smaller cities have a clear disadvantage there."

The Kalamazoo airport served 235,000 passengers on U.S. flights in 2010, according to government data, slightly less than the number at Lansing's airport. Both airports served about 11 percent of the number of passengers at Grand Rapids airport and less than 1 percent of the 28 million domestic passengers who went in and out of Detroit in 2010. Chicago's two airports counted nearly 72 million domestic passengers that same year.

Airlines will often lose money on flights from smaller airports going to major hubs, but then make up for it with profits on the popular flights between major cities, Kim said.

This focus on overall profits often makes cheap ticket airline prices seem illogical to consumers, since distance isn't always an indication of price.

The government price data show how prices don't always reflect flight distance. The average cheap ticket airline price from Kalamazoo to Minneapolis was $333, slightly lower than the average cost of flying across the country to Los Angeles.

As a travel agent in Battle Creek, Diane Carr sees firsthand how competition affects cheap ticket airline prices. Larger airports like Grand Rapids and Detroit tend to be less expensive, she said.

"They change all the time," said Carr of Ermisch Travel. "Sometimes (prices are) not much more. Other times it's like $100 cheaper," Carr said.

Travel agents said that traveling to smaller airports can also mean higher ticket prices.

In a recent price lookup, Dunn compared the cost of traveling from Kalamazoo to Portland, Ore., with the cost of traveling to a smaller airport like that in Medford, Ore.

The ticket to Medford was $788.20. The ticket to Portland was $570.00.

Distance traveled to an airport, difficulty parking, and the level of hustle and bustle at the airport can all contribute to a traveler's decision of which one to choose, Carr said.

But often, that choice is not Kalamazoo.

"We haven't done a Kalamazoo in a long time, because of the fact that it's so expensive," Dunn said.

If she had to guess at any given time which airport within a few hours of Battle Creek would be cheapest, Dunn said she would lean toward Detroit.

"Usually, Detroit is cheaper, but not now with the fuel that they have to pay to drive to Detroit," she said.