Fuel Air Explosives (and the irony of protection)

I've known of this class of bomb since I was around 8 : that's how hardcore a military spec fan I was. So indulge me. Also known as thermobaric weapons. But such weapons of mass destruction are very rarely used. Off the top of my head : used by the Russians against Chechnya, by the US against targets in Afghanistan more recently. Perhaps during the first Gulf War.

This bomb kills by overpressure effects, and also incineration. It contains a two stage fuze : first the canister explodes, distributing a mist of highly volatile particles into the air around the target, then the second fuze ignites.

Such flash ignitions occur catastrophically in civilian installations as well. The explosion is far more powerful than usual because of the high degree of pre-mixing of the fuel and oxygen. Milk powder factory explosions (in India) and grain silo explosions (in Canada and America) come to mind, as well as coal dust explosions in mines : anywhere where fine combustible particles are suspended in the air.

But done deliberately in a bomb : well. Upon ignition, overpressure reaches roughly 400 pounds per square inch, with the blastwave travelling at three kilometers per second. After that, the pressure drops far below normal, creating a vacuum and sucking everything back towards the blast zone. The massive overpressure and underpressure effects force unburnt fuel air mixture into every nook and cranny, incinerating everything at a temperature of 3000 degrees.

This effect is further magnified in confined spaces. Hence the use of FAE bombs against buildings, soldiers hiding in basements and caves, crew in non airtight vehicles - anywhere that the extreme high pressure air can force itself into. The more enclosed the area, the more devastating the effects. Ironically the best chance of survival for a soldier is to be standing in the open wearing no body armour (even the enclosed space between the armour you are wearing and your body magnifies the overpressure and acts as a space where the fuel-air mixture will penetrate).

This strange irony is also seen in the case of land mines. A soldier walking around barefoot that steps on a land mine might escape just losing a toe or two. If he's wearing steel jacketed boots it has been known for a land mine to slice off his leg mid calf where the boots end. In this case explosive force follows the path of least resistance, see.

another random girl

Take a peek at fullsized image first then click on comments for the rest of my post. =p

more on : fight or flight response

For those still skeptical about the idea that much of our brain's intelligence and cognitive ability comes from our ability to discard information.

Consider the stress "fight or flight" reflex. As our heartrate and adrenaline levels ramp up, among the filters we experience : first we lose peripheral vision (getting just tunnel vision) then our sense of hearing is impaired. We feel reduced or even no pain or discomfort. In fact our brain even stops recording memories of that situation, leading to severely impaired short term memory unless you consciously and deliberately choose to imprint what happened in your mind.

Fine motor control is impaired : but gross motor reflex is enhanced.

So the brain does have limitions on what we can focus on. The fight or flight response can be interpreted as the brain deliberately filtering out information it considers unnecessary. Shuts down some functions (recording of memory) it considers not immediately critical to survival. The benefit : enhanced attention and reflexes, total focus on the threat at hand.

I can attest to these physiological effects firsthand (but that would be another story). No sensation of pain whatsoever. Reduced awareness of sound. Tunnel vision. A host of other effects, but those are physiological not mental so they're not covered here. You could argue that these are just physiological effects that have side effects affecting the brain function : well they are interlinked, but I believe my interpretation is a reasonable one.

I would like this to mean that our brain is in fact extremely limited in what we can focus on : and the definition of focus is the act of discarding unnecessary information.

And yeah : if you are faced with a threatening situation (being mugged) etc be aware that these stress responses WILL occur, there is nothing you can do about it. But try to keep a cool head, commit every detail to memory so you will have an accurate report to give to the police (if you're still alive hehe). The best case outcome for the mugger is to steal your possessions with the minimum of fuss and zero injury (if you're injured, the police will be hunting them down twice as hard and fast for a much increased jailterm).

And don't stress ya =p

ever rejected a hug?

She's the only person I have ever refused a hug from - and more than once at that. You can tell if someone wants to hug you, the slight shifting of balance, the way she looks at you. It's also possible to signal rejection through body language alone, the way you hold yourself, the non receptive position of your arms. Once was when we touched down at the airport together in front of her family - what her intention was I still do not know. The second time, was in front of another guy that we both knew was desperately after her. Both times obviously desiring to use me to prove a point.

I'm acting cool to her because maybe I'm a little jealous. I want to spite her. You think you're so hot. But I deny you what you want sometimes to remind you that you cannot have everyone.

Man, how calculative am I... I'm just as bad as she is, and I know she is very very bad =p

dammit snipergirl!

Apparently I'm the number 1 search result for the search term "pedo-land" in some localized MSN search engines. And even the standard international one.

SNIPER THIS IS YOUR FREAKING FAULT

If I stop updating this blog you will all know that I have been taken away into life imprisonment in a maximum security facility and that you should blame Snipergirl for this. As my last will and testament I leave my computer to Flamebreaker since his computer is currently so crap.

Rawr.