Airline passengers for years complained about unappetizing, gooey, mystery-meat airline food. Now they're complaining that they don't get any.

Some passengers are starting to literally take matters into their own hands. Call it carry-on baggage for the gastronomically deprived. Business travelers in particular are turning a cold shoulder to airline culinary delicacies that more often resemble the contents of a brown bag lunch and bringing their own food on board.

Today an estimated 20 percent of passengers carry food aboard flights, says the Association of Professional Flight Attendants. The nation's airports are taking notice as earlier check-in requirements means their gates are full of hungry passengers. With more time, travelers have a smorgasbord of restaurants from which to buy food they can carry onto flights.

"It isn't an overnight trend," said Michelle Martineau Green, a senior vice president for Host Marriott Services, the Bethesda-based company that designs and operates airport concessions. "It is something that has been evolving."

One key reason is that airlines are indeed serving less food on flights in economy class. Airline spending on food per passenger peaked in 1992 and has continually declined since. Average spending per passenger dropped 25 percent in the four-year period ending in 1996.

"It's ongoing cost-cutting," said Terry Trippler, a consumer advocate for onetravel.com., an online travel service. "Business travelers are having a fit. With most of the food served in first class, the majority of passengers would send it back if they could. It isn't real good."

Raul Fernandez, a Northern Virginia technology CEO, is part of the take-on brigade. Every time he flies through Miami, for example, the Proxicom honcho grabs food from an airport eatery and munches on his flight home to Reston. "I get good Cuban food at the terminal," he says. "And the food on the plane is not what you would cook at home."

Even some major airlines are joining the craze. Delta Airlines, for example, offers tote-style paper bag meals on some short-haul flights. Other major airlines that have grown tired of the constant griping about their food are fighting back. Since 1997, United Airlines has hired chefs to develop tastier meals for their economy-class flights throughout North America.

Despite such efforts, passengers are flocking to food outlets in terminals. As part of a renovation at the Charlotte/Douglas International Airport, for example, officials constructed a new atrium for restaurants.

The demand led airport officials to place plastic bags near the checkout counters in which customers can store their purchases, said Jerry Orr, aviation director for the Charlotte airport. Since 1994, restaurant sales in the airport have risen nearly 50 percent, to $46 million last year.

As part of the expansion of Reagan National Airport, many restaurants and food kiosks were added, including Legal Seafood, McDonald's and Wall Street Deli.

Coffee has proved to be one of the most popular traveler choices, airport experts said. So it made sense for coffeehouses such as Starbucks to expand their airport operations. In the past seven years, Starbucks has opened 122 locations in 30 U.S. airports.

The lack of food on flights also causes some passengers to eat at the airport before boarding. On a recent afternoon at National, Terry Calvani, dressed in a pin-stripped suit, devoured a chicken wrap sandwich and large Coke as he read legal papers.

"I got here early, and I haven't had a thing to eat all day," said Calvani, who had been in Washington for the day on business. "Food at the airport used to be awful. But there is more competition and variety."

Host Marriott Services would not release sales figures, but said first-quarter food sales at National are up over the same period a year ago. At Dulles International Airport, the company said that food sales have risen largely because of an increase in the number of flights and a record number of travelers.

But the airlines are not thrilled with this trend. Airline regulations require that carry-on items be stored during takeoff. In some cases, that means flight attendants must take the coffee away from passengers and return it once the plane is in the air.

"You try telling somebody that just bought a $3 coffee that you need to take it away," said flight attendant Candace Kolander.

However, Kolander realizes food to go is inevitable.

"You have shopping malls in the airport now," she said. "The environment in the airport has changed, which creates a different environment on the plane."