[ars]

The air port has an x-ray machine, not a CT scanner. The CT has a ring the spins around the object making a 3d image - they don't have that at the airport.

X-rays are quite cheap in the medical world (reading them is where the cost is, not taking the x-ray).

[hallway_monitor]

I suppose a CT is what I saw at the airport earlier this year then - maybe Houston? The technicians clearly had a 3d model and were manipulating it to view it from all angles.

[habi]

There are CT machines at airports: https://petapixel.com/2019/10/21/beware-new-3d-airport-scann...

Technically, one can also get a (simple) 3D model of something with 'linear tomography', e.g. when the 'sample' is moved under the x-ray source, which happens in classic baggage scanners.