It is very likely that a large (15–20 cm in diameter), irregularly-shaped, cm-thick
pancake with beveled edges, taped to the abdomen, would be invisible to this
technology, ironically, because of its large volume, since it is easily confused with
normal anatomy. Thus, a third of a kilo of PETN, easily picked up in a competent pat
down, would be missed by backscatter “high technology”. Forty grams of PETN, a
purportedly dangerous amount, would fit in a 1.25 mm-thick pancake of the
dimensions simulated here and be virtually invisible.
So, not only is backscatter a massive invasion of privacy, it doesn't work anyway. For anyone that hasn't used PETN before, 330g would blow an aircraft to hell and back.
Funny you should post that link, as I just read it the other day. There was a demonstration of that on one of the news channels here,,, CNN AC360 maybe? I cant rememer which. Anyway, sure enough, a spread out mass with soft irregular edges was invisible to the machine. You couldnt see it on the scan at all,
Correction Mr. President, I DID build this, and please give Lurker a hug, we wouldn't want to damage his self-esteem.
I have some rather obvious problems with their methodology which include the direction of the detection. What if the view is from the side rather than straight on? I think they found exactly what they wanted to find.
If the view is from the side then it would be detected. The issue is the TSA have you standing in a common direction against the scanner (ie front-to-back), which is the direction they were using on their testing. The obvious fix for this is to have the people spin around or something and produce a full 3d model, but getting THAT past public opinion would be pretty entertaining.
Of course, nothing detects anything you've put inside your body which is the obvious way to get past any sort of pat down or scan.
