Thanks again for your reply. I think your points are reasonable-sounding, but do not make the case that TSA personal searches are useful.
Regarding the Philippine Airlines bombing: dude, that’s an example of how a carefully-considered and meticulously-planned bombing attempt DIDN’T cause a crash. Like the Aloha Airlines flight, it’s a data point AGAINST the need for the the TSA screeners.
Regarding the Lockerbie bombing: the amount of explosive in the crashed airplane is, of course, a guess. The total bomb volume, including detonator, power source, etc, was estimated to fit inside a Toshiba Boombeat cassette player. A picture of such a cassette player is here:
http://plane-truth.com/images/Toshiba%20radio%20RT-16.jpg
If a BoomBeat-sized item is required to hold the contents of a bomb, then that’s another way of saying that the total package, including explosive, batteries, and detonation circuit involves the sort of volume that cannot be hidden on the person.
Also note an experiment done by the BBC, reference 38 in this Wikipedia entry here:
http://en.wikipedia.org/wiki/PETN
According to that entry, using 80 grams of PETN, the BBC was unable to even “materially damage the airplane’s fuselage.” Granted, the Lockerbie residue included traces of RDX; RDX is 1.6 times the strength of PETN, and the official estimate of explosive used for the Lockerbie explosion is 311 grams, so the total explosive force used in the Lockerbie bomb could be 1.6 * (311/80) = 6.2 times the force used by the BBC test. Still, it’s a long way from being “unable to materially damage the airplanes fuselage” to a blast that:
cut through a metal cargo container
then cut through fuselage skin
and cut through support beams (which were stronger than normal support beams for this aircraft, since the plane was sometimes used for cargo carrying)
and, according to the UK accident report here:
http://www.aaib.gov.uk/cms_resources.cfm?file=/dft_avsafety_pdf_503158.pdf
then generated a “number of other regions of structural damage,remote from the explosion, which were clearly associated with severe and rapidly applied pressure loads acting normal to the skin’s internal surface,” and caused “two types of damage, i.e. the direct blast/tearing/petalling damage and the quite separate areas of ‘pressure blow’ damage at remote sites [that] were evidently caused by separate mechanisms, though it was equally clear that each was caused by explosive processes, rather than more general disintegration.”
Maybe the official report understated the amount of explosive required to cause an airliner crash. That would seem like a reasonable thing to do, so that future plotters would be more likely to fail.
On the other hand, maybe 311 grams of RDX, placed in the cargo hold of a 747, CAN bring down a 747. I don’t believe it, but maybe it’s true. Thing is, (1) passengers, even with the cheapest tickets, don’t ride in the cargo hold and (2) not all aircraft are 747s.
We already know from the referenced Aloha Air flight that a large loss of the passenger compartment fuselage from a 737 won’t cause a crash. We know from the referenced Philippines Air flight that even a carefully planned explosion from the passenger compartment of a 747 won’t cause a crash. Why then perform personal searches on people who will only have access to the passenger compartments of 737s? I’m thinking particularly of Southwest airline passengers, who fly in the passenger compartments of an all-737 airline. What’s the point of enhanced searches for Southwest passengers when history shows that even marked damage to the fuselage does not cause the plane to crash?
OK, with the entire preceding part of this post as background, I’m going to address what I believe is the fundamental question here: what’s the point of the “TSA” and the “security” procedures overall? Lots of people, myself included, have opined that the real reason for those enhanced searches may be to encourage travelers to submit to the largest mass radiation program in human history. The TSA delivers more doses of radiation each year than were delivered during the Hiroshima and Nagasaki blasts combined. On purpose or not, the TSA is also running a large-scale version of the Stanford Prison Experiments. Then, of course, there’s the issues regarding government unions, kickbacks, government fraud, etc. In short, the existence of the TSA may not be in the best interest of the public or of the Republic.
Is the TSA completely on the up and up? Why take that risk?
Why not let each airline set their own security policy, and remove whatever risk the TSA poses to the health of the Republic? I have no fear — none — that, say, the leadership of United Air Lines see themselves as having some mission to, for example, fundamentally change the USA into something else. I have no reason to believe that those UAL executives got into office with the assistance of known terrorists who openly plotted to kill 25 million Americans. Therefore, I’d have no problem with any UAL security procedure that makes even a modicum of sense. I can’t say the same about the TSA procedures. That’s probably the real bottom line here.
Thanks for reading, and thanks for your posts!
-The amount of explosive in the Philippine Airlines incident was 1 to 2oz. About as large as a whiteout bottle. The only reason it did not puncture the center tank was because the bomber used the incorrect seat chart for that model of 747.
-The Lockerbie bomb was SMALL and disintegrated a 747 almost instantly even without sparking a fuel tank. That is a tiny boombox 3x as wide as a cassette. However, the bomb itself was slightly larger than a cassette tape. It could have been concealed inside a walkman or reshaped into an underwear package just the same. Any bomber who isn't a complete idiot can hide a battery/detonator in practically any small electronic device. A skilled bomber can hide all the metal components inside a wristwatch. http://nickgilmartin.files.wordpress.com/2009/08/the-bomb.jpg?w=700
-The BBC test only used 80 grams of explosive and it was several feet from the wall. The pressure would obviously be distributed with such a small poorly placed charge. Even so, during the test there was damage and loss of pressure. If the test was performed under cruising pressure, I believe there would have been a significant hole. Aircraft are only tested to 150% of cruising ceiling pressure. They must be light and there is not much safety factor built in. For commercial airliners, we're talking a design pressure of only 20psi. Even a small bomb placed at the wall would easily generate several dozen times that local pressure. A slightly larger bomb (like Lockerbie) would generate the required pressure nomatter where it is was placed.
-Again, the Aloha flight is vastly different from bomb damage and should not be used to evaluate survivability of a bomb. The location of the designed fatigue failure points are intended for maximum survivability during a uniform failure of the pressure system. The airspeed at the time of the incident is not published but this was a 200 mile flight and it happened the instant the aircraft reached cruising altitude(the final fatigue cycle that led to failure). It was obviously flying below cruising speed.
