Wild blue yonder sprouts growth on the ground.

• Position: Economic outlook on North Carolina - Interview

Al Stuart is a professor of economic geography at UNC Charlotte. He got his doctorate at Ohio State University. Here he elaborates on an economic-impact study of North Carolina's 74 public airports he conducted for the N. C. Department of Transportation's aviation division.

BNC: Of the $9 billion impact, the majority is from four airports. Is that unusual?

The Atlanta airport dominates Georgia far more than these four together dominate North Carolina. That's because the population and industry are relatively dispersed. It's the 10th-most populous state, but you don't have any really large cities. In other states, big-city airports dominate.

BNC: How does $9 billion compare with other industries?

The numbers include other tenants and business users, visitors that spend their money in restaurants, hotels, travel agencies. So it's probably not fair to compare them with another industry. The direct employment is not as big as furniture or textiles and apparel, but it would rank it as one of the more sizable manufacturing industries.

BNC: Where is the bulk of the economic impact felt?

The goodies are more spread out, although it's predominantly a Piedmont phenomenon. In second place, as it were, are regional airports like Asheville and [TABULAR DATA OMITTED] Wilmington. For actual air service, it's really Charlotte and Raleigh-Durham, then Greensboro. And Wilmington and Asheville have more passengers than Winston-Salem.

BNC: Don't people think of only three big airports?

Winston-Salem is a maintenance facility. It doesn't really offer air service. But a major maintenance facility has a huge impact in terms of expenditures and jobs.

BNC: So maintenance facilities don't have to be at hubs?

No. A smaller, less-busy place would be easier to get in and out. It's essentially an industrial facility that requires proximity to an airfield. Planes are coming and going into these huge buildings and being overhauled. It's high-skill, high-wage jobs.

BNC: What does it mean to have a hub?

It's been a great advantage for Charlotte, even though there's some indication that because USAir dominate local flights, air fares are a little higher. One study measuring connectivity, basically the relative number of direct, nonstop flights you can...