KENNESAW — While a Gulfstream 3 jet zoomed overhead, county and business leaders celebrated the opening of new corporate jet hangar space at Cobb County Airport-McCollum Field on Friday morning.

The $7 million project added four 25,000-square-foot hangars at McCollum, which airport manager Karl Von Hagel said will increase capacity at the airport by 20 percent. It was built by Atlanta Executive Jet Center, one of the airport’s two fixed-base operators.

Atlanta Executive will have a 25-year lease with the airport for the six-acre tract, paying the county $6,009 a month. The agreement was approved in the midst of the recession in 2010. Once it expires, the hangars will revert to county ownership.

“This project is our community and our leaders saying we want to grow,” said Thomas Huff, president of Atlanta Executive Jet Center. “We don’t want to be a community standing in the background waiting for the economy to improve.”

Von Hagel said the county didn’t provide any economic incentives for “Corporate Row,” as the group of hangars is known. But NCR — which last year received a $5,000 cap on building permit fees as well as $50,000 in cash from the Development Authority of Cobb County to keep its jet at McCollum — is interested in moving into one of the new hangars from its current space at McCollum.

While he said most of the companies interested in leasing the space don’t want to be identified, Huff said Atlanta-based Archer Western Contractors is among those planning to use Corporate Row. By the time the hangars are available, which is expected within the next month, he expects them to be 65 percent to 70 percent occupied. They will also include what he called the most advanced fire suppression and evacuation systems in the Atlanta area.

Currently, Von Hagel said the airport is 100 percent occupied.

While the new hangars are currently empty shells, Von Hagel said Atlanta Executive will build to suit if companies want to lease a hangar. With airlines cutting back service, he said many could find using private jets appealing.

“If you go down to Hartsfield, and you want to go to meetings in two different cities on the same day, it’s almost impossible,” he said.

Northwest Cobb Commissioner Helen Goreham, whose district includes McCollum, said the project could eventually add jobs to the county and will affect business beyond the airport.

“As we bring in more corporations to the county, they can bring in their jets,” she said. “We bring in pilots, we bring in mechanics. Individuals who are going to spend money in our stores and eat in our restaurants.”

McCollum is considered a reliever airport for corporate and general aviation users, averaging 183 takeoffs and landings a day. Von Hagel said 200 employees work there daily, and a recent state economic impact study found it contributes $112.4 million annually to the community and is responsible for 842 total jobs.

Since 2000, the Cobb Board of Commissioners has authorized $27 million on airport projects, Von Hagel said.

With items on the July 31 TSPLOST referendum that would spend $3.2 million on a new control tower and runway lights at McCollum, Huff and county Chairman Tim Lee plugged the upcoming vote to authorize a 1 percent transportation sales tax in the 10-county area.

“On the 31st of this month, we need to vote for the TSPLOST, so that we can get a new control tower, and that our roads and infrastructure continue growth in this area,” Huff said. “So please mark your calendars. Every vote is going to count.”

Other officials attending Friday’s 30-minute ceremony included northeast Cobb Commissioner JoAnn Birrell and southwest Cobb Commissioner Woody Thompson, Kennesaw Mayor Mark Mathews and state Rep. Don Parsons (R-northeast Cobb).