Go from your car to the gate in fewer than 15 minutes. That’s one of Mario Rodriguez’s pitches to convince fliers to choose Long Beach Airport over Los Angeles International, 20 miles away.

Long Beach handles only about 5 percent of the traffic of bustling LAX, but it preaches convenience and friendly service. The airport recently overhauled its terminal, adding a wine bar with fire pits. Long Beach enjoys a customer rating of four-and-a-half stars on Yelp, two stars higher than the neighboring hub.

“We realized one thing: travel (is) a really bad experience,” said Rodriquez, director of the 90-year-old Long Beach Airport. “We treat our customer the way we want to be treated.”

Secondary airports have to carve out a niche, Rodriguez said. Finding a sweet spot in the metro Atlanta travel market will be the key challenge for a private investment group planning to start airline service at an airport in Paulding County, northwest of downtown Atlanta.

It won’t be easy.

Carriers by and large are shrinking, not growing, as fuel prices and a still-wobbly economy suppress demand. The Paulding project backers haven’t yet identified an airline that will commit to their plan.

The airport in Gary, Ind., has tried for years to become Chicago’s third commercial airport, but airline service there ended earlier this year and Gary officials are plotting next steps in a major reconfiguration. Politicians in neighboring Illinois are starting the long-stalled process of building another commercial airport south of Chicago.

Phoenix-Mesa Gateway Airport has established itself to leisure travelers as a counterpart to Sky Harbor International Airport in Arizona’s biggest metro area, but it’s taken nearly 20 years since the process started to convert the former Air Force base into a passenger airport.

A second metro Atlanta airport has been discussed for decades, but the push has never gained much traction. Reasons vary, from pushback by residents surrounding potential sites to the opposition of hometown megacarrier Delta Air Lines, which takes a dim view of any foot-in-the-door operation that could grow into a competitor to its hub at the Atlanta airport.

Delta’s CEO already has said the carrier will lobby against government funding to fuel the Paulding project.

Propeller Investments, the New York-based investment firm planning to start commercial flights from Paulding Northwest Atlanta Airport, failed to win political approval in an earlier bid to start airline service at Gwinnett County’s Briscoe Field.

Propeller officials want to start in Paulding with one airline with a few flights per week. The firm says it will announce an airline by year’s end. It’s part of a broader plan, in partnership with Paulding officials, to turn the sleepy airfield along Ga. 278 near Dallas into a magnet for aviation-related businesses.

The consumer impact of the Paulding plan is hard to assess until an airline lays out its plans. At the initial service levels envisioned, Paulding would offer an extremely limited alternative to Hartsfield-Jackson International, which has more than 1,000 takeoffs per day and connects to destinations worldwide. And if the airline specializes in the package tour business, as some small carriers do, much of its customer base would be fliers who make booking decisions on the basis of the whole deal, not the airfare or airport.

A big carrier could have a more direct effect on competition, perhaps by offering flights from Paulding to a hub where fliers could connect to an array of destinations. But most — American, United, Southwest etc. — already fly to Hartsfield-Jackson. There are business advantages for airlines to cluster together, and established carriers don’t often try to go it alone from a smaller airport, said Mark Sixel, an airline consultant in Oregon.

For commercial service to work, Sixel said, the Paulding investors will most likely need to appeal to vacationers who don’t want to deal with the hassle of getting to Hartsfield-Jackson, or the challenge of wrangling kids through its cavernous and crowded concourses.

But while convenience can be a secondary airport’s calling card, it also must fit into the transportation system of a major metro area, said Rodriguez, the Long Beach airport director, who was previously at Ft. Lauderdale International, a reliever to Miami’s main airport.

Regional commercial airports need to have desirable destinations and reliable schedules, he said. For carriers to come and invest, they need a sizeable local population or be near a popular destination, Rodriguez said.

“If the carrier doesn’t see it’s a yielding market, they won’t come,” Rodriguez said.

Long Beach has four carriers that serve 13 cities across the country, including Delta’s hub in Salt Lake City and US Airways’ hub in Phoenix.

About 70 percent of the 3.2 million passengers who go through Long Beach each year are leisure travelers, but savvy business fliers also use it for quick trips to Sacramento and points up the West Coast.

In Phoenix, Wayne Balmer remembers the pieces were in place to convert an Air Force base east of Phoenix into the region’s second commercial airport.

The city’s bustling Sky Harbor airport would eventually need relief, and the metro Phoenix growth was aimed squarely at the closing Williams Air Force Base in the region’s East Valley, said Balmer, who was formerly the project manager for the Williams-Gateway conversion for the city of Mesa.

Local and state leaders created an airport authority with surrounding jurisdictions, and built the infrastructure, including highways and utilities, to support the airport. But there were hurdles. The Sept. 11, 2001, terror attacks chilled the airline industry, delaying commercial services.

Ultimately, the airport had to rely on small carriers, Balmer said, and the roster has changed over the years.

Today, Allegiant Air, a smaller carrier that specializes in vacation packages and charter flights, has built a strong base there, Balmer said. Allegiant focuses on flying to destination markets, often using secondary airports.

“People refer to it as a 20-year overnight success,” he said.