When Charlotte Douglas International Airport announced last month that it would spend $70 million to renovate Concourse B, one of the two concourses used exclusively by hub carrier American Airlines Group Inc. (AAL) , the news wasn't exactly earth-shattering.

Most major U.S. airports are involved in building projects, headed by a $14 billion project at Los Angeles International Airport and $11 billion in spending at the three New York airports. Last week, Pittsburgh International Airport announced plans for a $1.1 billion improvement project.

Charlotte, meanwhile, is in the midst of a $2.5 billion project that has one unique component: Charlotte's passenger facility charge (PFC) is at the minimum $3 level.

According to the Federal Aviation Administration, 29 of the 30 largest U.S. airports collect the maximum allowed PFC of $4.50. Charlotte doesn't.

Also, 28 of the 29 medium-sized U.S. airports collect a PFC of $4.50. Only Ted Stevens Anchorage International Airport is at the $3 level.

A passenger facility charge is a fee, added to an airplane ticket cost, for each departure or connection, with a maximum of two PFCs (typically $9) per trip.  Airports use PFCs to fund airport improvement projects.

"Charlotte is the only large hub in the country that does not have the maximum PFC," said Mike Minerva, American's vice president for government and airport affairs.

"The way things are done in Charlotte is that airlines and the airport get together to decide what needs to be done," Minerva said. "At other airports, sometimes there is more conflict."

Besides the lowest major airport PFC, Charlotte has the lowest major airport cost per enplanement, the amount each airline pays the airport for each passenger. Charlotte's 2016 CPE was just $1.35, Cagle said. Highest cost airports, such as New York's John F. Kennedy International, can have CPEs in the $25 range.

Minerva and Brent Cagle, Charlotte Douglas' aviation director, were interviewed last week at the Airlines for America airline summit in Washington.

With 677 daily departures to 156 destinations, Charlotte is the second-largest hub for American, which has about 90% of the airport's departures.

"In a primary hub, it doesn't make any difference whether the PFC is raised or if goes to rates and charges," Cagle said. "We truly listen to the airlines.

"We add facilities when they're needed by the airlines," he said. "We've never had anything but 100% agreement by the airlines. It's not an 'if you build it they will come' model."

Airport history is replete with instances where airports proposed charges that incumbent airlines resisted. One example occurred in the early 2010s, when Philadelphia International Airport proposed a controversial expansion plan estimated to cost between $1 billion and $3 billion. Airlines led by American predecessor US Airways were publicly opposed.

In May 2017, Philadelphia and its airlines agreed on a $900 million improvement plan.

Besides a positive relationship with tenants - the relationship with the primary tenant began when Piedmont Airlines started to build a small Charlotte hub in the early 1980s -- Charlotte has a history of efficient operation. Cagle noted that "we run 45 million passengers {annually} through 1.8 million square feet in the terminal.

"We are usually highest in utilization or very near to highest," Cagle said.

Charlotte's $70 million Concourse B will renovate the aging concourse over the next year. Longer term, Cagle wants to lengthen and widen all four of the airport's mainline jet concourses, but that work must wait until an ongoing expansion of Concourse A is completed and can provide new gates to use when other concourses are shut down.

Long-term renovation, part of the ongoing $2.5 billion improvement project, will add 25 new gates, bringing the total to 125.

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This article is commentary by an independent contributor. At the time of publication, the author held no positions in the stocks mentioned.

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