Since CT (Computer Tomography) was invented, it has significantly enhanced our ability to map objects in obscured areas. Originally utilized in a medical context to scan organs and bones, it is now being used in the context of airport security .
With technological advances, CT scanners are now small and convenient enough to be used at scale, scanning hand luggage items with higher reliability and speed, making them convenient for commercial aviation customers. Simple Flying is diving deeper into how CT technology works, how it has changed in recent years, and whether further changes to the industry might be coming down the line.
Photo: American Airlines A rapidly changing field
It was not always the case that aviation customers were required to follow the level of security procedures that we do now, but it should go without saying that flying is dangerous. When passengers are ten thousand feet up the pressurized cabin of a vehicle that propels itself with controlled explosions, everyday items such as aerosol containers and batteries can easily invite disaster, endangering hundreds of lives.
Instances of global terrorism were also catalysts to change, exposing how vulnerable the field of aviation was. The best example is 9-11, which occurred in 2001. After this tragedy, many new rules and legislation were brought in and the face of aviation security rapidly changed, according to the Associated Press.
Related 20 Years Since 9/11: A Reflection Posts
However, the convenience we used to enjoy may return, if only in a small way, thanks to improvements in CT technology in recent years. Indeed, the technology has rapidly advanced since the first CT scanner was built in 1967, as illustrated by the International Society of Computed Tomography. Now, it can even detect potent acids and explosives in liquid form, giving hope to aviation customers that their expensive bottle of innocently packed sunscreen will not go tumbling into the waste bin at the hands of a stony-faced security officer.
Photo: TSA No such luck, travelers
Though CT scanners can now be equipped to detect hazardous liquids in closed containers, aviation security procedures have not yet changed, despite hope to the contrary. As covered previously, the Transportation Security Administration (TSA) indicated passengers may need to wait until 2040 before scanners are distributed widely enough to provide a decent security net for such items in the US:
"TSA is still deploying Computed Tomography (CT) units that are capable of screening larger sizes of liquids, however the agency will not be able to change the current 3-1-1 liquids rule for some time to come, because there are about 2,000 screening lanes in about 430 airports."
As I'm sure you know, dear reader, current security procedures can make getting through security uncomfortable and dehydrating, meaning a rush immediately following security to grab a drink and visit the restroom. According to the TSA, the 3-1-1 restrictions also apply to objects such as toothpaste, shampoo, conditioner, mouthwash, and lotion, the very things one would want near at hand when going on holiday.
Photo: Renful Premier Technologies How does computer tomography work?
Once upon a time, 2-D X-ray imaging was used to scan carry-on bags, but through the integration of computing, much more information can be gleaned. As described by HowStuffWorks, bags pass over a conveyor into a rotating array of X-ray imaging devices. As it travels, the bag is pictured from multiple angles, and this information is compiled into a 3-D image via computer, and objects are isolated. These images are then checked against databases of harmful items and processed using algorithms, thus harmful items can be recognized and flagged by their shape.
Taking this process one step further, substances can now be chemically recognized, whereas previously, they could not. This technique is called Raman Molecular Spectroscopy and can be integrated into modern CT scanning facilities, according to Agilent. Where previous chemical detection "sniffed" for offending material being left on the outside of a container, this process can scan contained liquids through solid objects, identifying them by their molecular structure. While this advancement is impressive, I'll be sad to see the hard-working sniffer dogs become obsolete.
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Posts 2 How widespread CT technology is today
It appears that change is slow to come. In 2022, the UK government set a deadline for all major UK airports to transition to this technology by June 2024. However, according to Airport Industry-News, many major UK airports have been unable to meet the deadline, and extensions have had to be granted. According to Block Imaging, the price for individual units can range from $80,000 to $300,000, depending on their capability. With passenger numbers being lower than expected post-COVID, according to the UK government, this expensive equipment may be very slow to arrive in the country.
As for the US, the TSA is awarding $781.2 million to help speed CT integration into airports. However, 2,000 screening lanes in about 430 airports is a very low number for such a large country, meaning the US lags behind the UK in this field. If based in the US, it may be worth keeping up to date with the TSA, as they have been known to announce when new scanners are delivered. The TSA shared last year how new scanners are being used at West Virginia International Yeager Airport.
Related Newark TSA Checkpoints Fitted With New 3D Explosive Detection Scanners
The new scanners allow travelers to leave laptops and other electronic devices in their carry-on bags.
Posts 1 Optimizing future security procedures
One advantage of this new technology is that items such as laptops can be left in carry-on luggage, rather than passengers having to get them out. This is because newer multi-angle CT scanning technology can identify constituent electrical components, even at oblique angles. Reducing this extra step in the security procedure helps to optimize passenger flow through security, reducing wait times overall.
Third-party optimization companies, such as Copenhagen Optimization, provide bespoke optimization solutions for airports. According to the company, CT scanning is an integral part of this optimization process. Perhaps, through more technological integration and automation, having to arrive hours before one's scheduled flight might eventually become a thing of the past.
Is it really necessary to arrive at the airport three hours early? Our analysis here.
During research for this article, one idea I have seen mentioned often is reducing contact between the passenger and screening staff. Companies appear to be aiming for a completely automated and impersonal screening process. Smiths Detection is a company that supplies CT scanners. This may increase efficiency at the security checkpoint, reducing the chance of stress-fueled arguments or idle chatter, but I prefer the human touch. I'd go as far as to say that the utter boredom on the faces of security attendants I interact with has a calming effect.
Photo: Leidos Full-body scanning - not new, but useful
Using similar technology to CT, the full-body scanner is another addition to the airport security arsenal. Though this technology is older than current CT luggage scanning, being commercialized in 2006 and eventually acquired by Leidos, it is useful and impressive. Unlike metal detectors, which a passenger would walk through after removing metallic items, these scanners send 'millimeter waves' (radio waves for those interested) at the passenger, to form a picture of the passenger's body and insides.
They can detect all kinds of objects, using algorithmic detection to alert staff of suspect objects. According to Reader's Digest, current iterations of this technology simplify and translate the passenger's body into a cartoon avatar, and indicate objects worthy of investigation using visual tags.
Increasing security while reducing intrusive procedures
Overall, CT and full-body scanning appear to have an ethos of increasing efficiency through holistic changes. Using computer integration, the security checking processes have become more reliable and speedy, without the need for increasingly intrusive checks, removing the need for passengers to take off their belts, unpack their laptops, etc. This is good news for those of you (like me) who may have been worried that increased security might mean a loss of personal choice or increased embarrassment when passing through the security checkpoint.
Can I be certain that more draconian security measures, such as mandatory subdermal identification chips, will not eventually be implemented? No. However, if airport security technology continues with its current ethos, the marginal increases achieved by clever technological strategy may significantly affect wait times in the long run. Third-party companies such as Copenhagen Optimization specializing in efficiency may shave off wait times even further. In this way, air travel may eventually become much less stressful and more expedient for the average passenger.