The move comes after Transportation Security Administration warnings about long security lines this summer at the nation's big airports due to high traffic and low staffing.
Hartsfield-Jackson Atlanta International Airport shut down its south TSA security checkpoint on Wednesday for three weeks of screening tests, forcing thousands of domestic travelers to pass through the airport's two remaining checkpoints.
More people move through this airport than any other. It handled more than 100 million travelers last year.
The project -- a collaboration between the airport, the TSA and hub carrier Delta Air Lines, aims to install automated security screening equipment in two of the four lanes at the south checkpoint.
The new equipment would be operated by TSA workers, but the bins passengers place their belongings in are automated so screeners don't have to spend time recirculating them.
Another part of the automation involves sending suspicious bags to a separate conveyer belt.
The equipment is similar to systems employed at London's Heathrow and Amsterdam's Schiphol, the TSA said.
When it re-opens on May 24, officials will be able to make side-by-side comparisons between the automated security lanes against regular lanes.
The results will help the TSA create a pilot program that could be replicated at other airports.
Airport workers wearing green vests set up yellow tape throughout the airport's central atrium and have been helping uniformed TSA agents direct line traffic.
Additional lanes have been opened at the airport's other checkpoint areas to compensate for the shutdown.
"Waits have been north of 30 minutes and have been as short as 10-20 minutes," said Reese McCranie, the airport's communications director.
Hartsfield-Jackson is at full staff and workers have been shifted to wrangle passengers at other checkpoints. "It's all hands on deck for us," he said.
After driving two hours from Anderson, South Carolina, Mike Robles was hoping to make his flight to Chicago Friday.
But from his position in line in the middle of the airport atrium, far from the security checkpoint, he wasn't feeling confident. "It's slowing things down," he said, "So it's making me sweat it a little bit.
"When I've come through Atlanta before, it's busy, but you get through in a timely manner," Robles said. "Now, it seems a little bit longer and we're moving a little bit slower."
Robles said he wasn't aware the airport had shut down one of its security lines.
The shutdown of the south checkpoint began Wednesday and is expected to last until May 24.
In February, Atlanta's airport sent a tersely worded letter to the TSA complaining about "inadequate" staffing and warning about increasing passenger traffic this summer.
The letter threatens to abandon TSA in favor of privatized passenger screening, unless something is done.
Homeland Security Secretary Jeh C. Johnson said he has called on Congress to approve more money to pay for overtime for TSA officers working at airports across the nation this summer during peak periods.