World's Mega Hub Airports See Enormous Growth

Atlanta’s Hartsfield-Jackson International Airport now serves more than 100 million passengers a year.

It’s a staggering number that represents a nearly 30 percent increase from 2016, but not entirely surprising given that it’s the world’s busiest airport.

Hartsfield Jackson is just one of the world’s “mega-hubs” that’s seen substantial year-over-year growth, according to a new industry report from Airlines Council International.

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Airports located in advanced economies experienced a resurgence in passenger traffic with year over year growth of 5.2 percent, according to the World Air Traffic Report.

The report, which includes more than 2,400 airports in 175 countries, notes that airports in large cities are gaining passengers, while those in small towns are losing them.

"The downside of airline capacity shifts is that a proportion of smaller regional airports have either stagnated or experienced a reduction in nonstop destinations between cities," Angela Gittens, director general of ACI World and a former Hartsfield-Jackson general manager, said in a statement.

The stagnation can also be tied in part to carriers such as Delta Air Lines reducing their fleet of smaller regional planes that typically serve smaller towns, according to Associated Press.

In addition, Southwest Airlines, which acquired AirTran Airways, canceled service to some of AirTran’s routes, which included smaller markets.

"It is important to highlight that the reason smaller airports remain in operation hinges on the fact that they contribute to the local, social and economic development of their surrounding communities," Gittens said. "Strategies to ensure their sustainability are important if we are to have a robust aviation system."

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Worldwide airport passenger numbers increased 6.5 percent in 2016 to almost 7.7 billion. The highest number of passengers traveled through airports in the Asia-Pacific region, which was up 10 percent over 2015.

In terms of sheer passenger counts, Beijing was the world's second-busiest airport last year, behind Atlanta, with 94 million passengers and 5 percent growth. Dubai came in third with 84 million passengers and 7.2 percent growth.

Leading the pack of the fastest growing airports meanwhile were New Delhi, India; Incheon, Korea; Kunming, China; Barcelona, Spain and Mumbai, India.

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