There is a glimmer of hope that the frustrating, slow airport security experience will get a little smoother over the next few years.
In a partnership with American Airlines, the Transportation Security Administration introduced a new kind of machine last month to screen carry-on bags in Terminal 8 at Kennedy International Airport in New York.
The machines, the agency says, improve on the current system, in which most travelers have their carry-on bags screened by X-ray machines that produce only two-dimensional images of their contents. If agents are unsure of what they’re seeing, they pull the bag aside and inspect its contents manually.
The new machines use computed tomography, a technology that produces three-dimensional images so detailed they can even show the mass and densities of items in the bag, including liquids inside their containers. With the new machines, the T.S.A. says, security agents will be better able to analyze what is inside a bag and will be less likely to have to perform searches by hand.
“C.T. is something that has been looked at to respond to the threats against aviation security since the 1990s,” said Keith Goll, the acting deputy assistant administrator for the agency’s office of requirement and capability analysis.
The technology has been used to screen checked baggage since shortly after the terrorist attacks of Sept. 11, 2001. The T.S.A., formed after the attacks, explored using C.T. machines to scan carry-on bags as well, but Mr. Goll said the technology was not developed or compact enough to be effective, until recently.
“Based on the progression of the technology and the emergence of some of the threat streams we had over the last year, it was time for T.S.A. to take a look at this technology and see if it was ready,” Mr. Goll said.
The machines were used first in Phoenix and Boston in June 2017 before arriving at Kennedy. Mr. Goll said that the agency preferred to test new technologies at big airports, where many different kinds of travelers will interact with them every day.
“We really want to stress the system,” he said. “We want to put it in two sites that aren’t the same to see that the equipment performs in multiple settings.”
Those trials, he said, help the T.S.A. identify the capabilities and limitations of the machines. When the results of those trials are in, he said, the agency plans to update its screening guidelines, probably allowing passengers to leave more items in their carry-on bags.
Before the public tests, the T.S.A. runs laboratory trials to make sure the machines are up to their tasks.
“There’s a minimum performance requirement for the type of explosives and the amounts it has to detect,” Mr. Goll said, “so we test the equipment in a laboratory before we ever put it in the airport.”
He said terrorist groups study “what we have out there.” As a result, “it’s fair to say we need to continually update our technology to find what we’re looking for,” he said. “That’s where C.T. comes in. It gives us the ability to do that.”
Though the T.S.A. has not yet announced a specific timeline for bringing the machines to more airports, Mr. Goll said more should be installed next year.
“You’ll start seeing in 2019 a much greater deployment,” and that will continue over the next few years, he said.
Despite these efficiency efforts, the T.S.A. has opted not to pursue a cost savings proposal to shut down screening sites at small airports, an idea that gained national attention earlier this month, agency officials said.
Eventually, it may be possible for travelers to pass through security checkpoints without removing anything from their bags. But for now, most existing screening regulations for carry-on luggage will remain, even in lanes that use the new machines.
“As the C.T. program evolves,” said Michael Bilello, the assistant administrator for public affairs at the agency, “there will be an evolution of what passengers can keep in their bags.”
The biggest change right now is that passengers using the C.T. lanes will be able to leave their laptops in their bags for screening, and as the trials progress, more items may be able to stay in bags.
“At the end of the day, this will result in a more streamlined passenger experience through the checkpoint,” Mr. Bilello said.
The current screening procedures can be an expensive inconvenience for both passengers and airlines.
“Inevitably, you’ve got a lot of different travelers going through security lanes, and there’s always going to be new travelers who don’t know the rules holding up the lines for everyone,” said Brian Kelly, founder and chief executive of The Points Guy, a website that publishes airline news and recommends techniques to maximize the use of frequent flier miles. “It gives you anxiety and it wastes your time.”
Mr. Kelly said he was optimistic that new technology would make security screenings less stressful and more effective.
“The mass conditioning of travelers leads to confusion that leads to delays,” he said, referring to all the rules about how various items have to be screened. “I think the C.T. scanning machines will speed up the process.”
He also said that airlines have an incentive to make screening more efficient for their passengers.
“When passengers miss flights because of security delays, which still happens quite a bit, the airline has to take time rebooking them,” Mr. Kelly said.
Officials at American Airlines, which is working with the T.S.A. for the trial at Kennedy Airport, agreed.
“At American, we are always looking at ways to invest in technology that raises the bar on global aviation security while improving the customer experience,” José Freig, the airline’s chief security officer, said in an emailed statement.
Mr. Kelly said it came down to making travel safer and more efficient.
“I think it’s really important, even for safety, that we replace relatively untrained humans looking eight hours a day at a screen for weapons,” he said.