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Backscatter X-Ray Machines Easily Fooled
Pinckney writes "A paper by Leon Kaufman and Joseph W. Carlson in the Journal of Transportation Security asserts that x-ray backscatter machines are not very effective (PDF) even in their intended role. While carelessly placed contraband will be detected, the machines have glaring blind-spots and have difficulty distinguishing explosives from human tissue. As they write, 'It is very likely that a large (15–20 cm in diameter), irregularly-shaped, cm-thick pancake [of PETN explosive] with beveled edges, taped to the abdomen, would be invisible to this technology. ... It is also easy to see that an object such as a wire or a boxcutter blade, taped to the side of the body, or even a small gun in the same location, will be invisible.'"
It's highly questionable whether the machines are even capable of identifying "suspicious areas of the image." But suppose for a moment that they are. These scanners are already, in themselves, more of a safety hazard than actually flying. They have been through nowhere near the degree of rigorous safety testing and analysis that any component of an aircraft has to go through. While exposure to the intended dose of radiation for a scan may be safe (even that is debatable), the scanning process is software controlled. Imagine if the software crashes in the middle of a scan, or the scanner mechanism sticks.
And now, suppose that it is possible to detect suspicious areas of an image and do a more thorough scan. This simply increases the safety risks of these machines. X-ray scanners? How is that exposure going to be controlled? Is testing ever going to be held to the degree of rigor required for aircraft? If not, why should we be willing to accept the risks of using these machines?
The fact is that if we really care about people taping explosives to their stomachs, the only way to detect this is with a thorough search (a.k.a. "enhanced patdown"). If we are really that concerned about security, that is what every traveler should be subject to. And if we aren't comfortable with searching passengers like that, then we really ought to stop being such cowards and accept the quite minimal risk that someone is going to get one of these Rube Goldberg explosive devices past security and actually succeed in harming an aircraft with it (unlike the shoe-bomber and underwear bomber attempts, which did not harm either aircraft).
Why didn't the TSA test this technology first to make sure it works? I mean, it's not like cloth tape and a flattened explosive are unprecedented or amazingly cunning bits of circumvention! Why not hire 20 nerds and give them a week to figure out if they can sneak something truly dangerous through the scanner? As long as they can do so reliably, wait for the next version of the machine and test again. Only when it works should you place the order!
Precisely. The shoe bomber got through, and his bomb didn't work. Ditto the underpants bomber. Airport security failed miserably. It didn't matter.
As for the liquid bombers, it's still debatable whether their bomb would have worked, but who cares? They never even made it as far as the airport!
I am still waiting for the TSA to present the American people with any evidence -- even the tiniest shred of evidence -- that they have ever once in their entire history caught an actual terrorist.
>not very effective (PDF) even in their intended role
You're implicitly buying in to the claim that their intended role has something to do with safety.
The purpose of a system is what it does. The ~$200,000 scanner purchases funnel tax money to a company which made payments to the former director of Homeland Security. They condition people to being treated like prisoners. The first was deliberate.
They're working perfectly.
That's because airport security is security theater. Even with terrorism and accidents, planes are already the safest way to travel between two points. The security at the airport is just a dog and pony show to reassure fliers and give the impression that the government is "doing something about it". The effectiveness of the security measure is rather meaningless because a 50% reduction in almost-never will still be almost-never.
In fact concern over the new scanners and pat-downs at airports is probably going to kill more people than any terrorists. People uncomfortable with the invasion of privacy may choose to drive to their destination rather than fly. And you're roughly 15-20x more likely to die from an automobile accident than from a plane crash/terrorist incident over a trip of the same distance.
"These scanners are already, in themselves, more of a safety hazard than actually flying. They have been through nowhere near the degree of rigorous safety testing and analysis that any component of an aircraft has to go through."
Consider the level of testing and analysis that the *very same device* would require if it were labeled "medical equipment" rather than "airport security equipment". Consider also the site and personnel licensing required to operate one (probably akin to that required for a modern xray machine).
~REZ~ #43301. Who'd fake being me anyway?
Behavioral profiling, such as what is practiced by the Israelis, is both cheaper and more effective than searching for weapons. If we adopted behavioral profiling, screened all baggage for explosives and ran passengers through the air-puff chemical sensors we'd have a system that protects travelers privacy much better, is much more effective and significantly cheaper than our current system.
Explosives are the real threat anymore. A few terrorists wonldn't be able to take over an airplane, not now that the passengers will fight back and the cockpit doors are reinforced. Preventing passengers from bringing things like nail clippers is just asinine.