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The plane in question was a on a (very) short-haul flight between two islands in Hawaii. As such, the plane never got very high up, the maximum cruising altitude was only 24,000 feet. The Airbus A380 is a BIG plane that will be used pretty much exclusively for long-haul flights where the cruising altitude will usually be a fair bit higher, typically around 35,000 feet.

The difference in how serious a decompression is a 24,000' vs. 35,000' is quite significant. You can find some data here (thanks to the person who linked the article earlier in this thread). Basically at 24,000' you've got at least a minute and a half before the lack of oxygen makes it impossible to function. At 35,000' that time could be cut down to only 15 seconds. In the article you listed it mentions that after the decompression they made an emergency descent at 4,100 feet per minute. This would bring them down to a relatively "safe" 10,000' within a few minutes. If they had been flying at 35,000' then anyone not wearing an oxygen mask would be unconscious before they made it down to 30,000'.

Navy flight surgeon http://www.vnh.org/FSManual/01/03Hypoxia.html/ gives you a maxium of 45 seconds of useful consciousness at 35000 ft. assuming a rapid loss of cabin pressure. Its only 45 seconds at 40,000. This is assuming that you are sitting still. If you are preforming "moderate activity" (say screaming your head off because you are are scared stupid) it drops to 30 and 18 seconds (35 and 40 thousand ft, respectively.) Even 30 seonds isn't a lot of time. You need to recognize that there is a problem, identify the problem, and correct it, all in that time, with impared cognitive abilities due to hypoxia. If you're a hot shit Navy Jet Jock whose trained for years to handle that kind of conditions, then no problem. If you are the average airline passenger (and likely the average airline pilot) that's not nearly enough time. I have no idea how violent a depressurization of this kind would be, but if it didn't rock the plane too much, the pilot's first warning that something is wrong might be when he passes out. Hypoxia = nasty

> 70-0 mph in less than 0.2 of a second is not easy to support by the human body...

Not so hard really,
acceleration is velocity change over time:
70*1800/(60*60)/0.2=175m/s^2

put that in terms of g and we get about 17.8g

then if you look up some crash data:
http://www.vnh.org/FSManual/02/03ImpactAcceleratio n.html
(table 2.6) turns out it's unlikely to cause a whole lot of injury (as long as you're supported well)

> Unfortunately, anybody in the car at the time
> would be dead due to internal injuries. No amount
> of safety cages, seat belts and air bags will stop
> your guts from going splat internally when
> decelerating from 70mph to 0 in about 1 meter.

Are you sure about that?

say we start at 70mph, which is u=70*1800/(60*60)=35m/s.

Assume the deceleration is uniform, then we can say
v^2=u^2+2as,
now say that the final velocity, v, is zero, and the displacement s is 1.0m, the acceleration a works out as
a=(35**2)/(2*1.0)=612m/s^2
or about 62g

The duration of the impact will be
(70*1800/3600)/612=0.06s

Now, to judge how deadly this is, we look at some data:
http://www.vnh.org/FSManual/02/03ImpactAcceleratio n.html

Table 2.6 gives tolerable x direction accelerations of 45-85G depending on whether it is +x or -x direction with times between 0.04 and 0.1s. the earlier charts give similar information.

So even if we do come to a dead (hopefully not literally!) stop from 70mph in one metre, it is very severe, but it is in the range of accelerations that can be survived. The difference between survival and death is likely to be down to the quality of the restraint system "safety cages, seat belts and air bags".

Excuse me?

Actually half the reason we have as much waste as we do is because of the moratorium on breeder reactors. The U-238 (nuclear waste/depleted Uranium) coming out of traditional Light Water Reactors can be used in Breeder Reactors to generate more power (and reducing the need to store waste materials). This end product of the process, however, is weapons grade Plutonium-239 and some more U-238 (a smaller amount of U-235 is required as an initiator for the reaction).

http://hyperphysics.phy-astr.gsu.edu/hbase/nucene/ fasbre.html

What alarmists also fail to note is that the resulting Plutonium can be used to fuel yet another form of nuclear reactor. Plutonium Pellet based reactors are not only very efficient, but also one of the safer forms of reactor.

Unfortunately concerns about both weapons grade and reactor grade plutonium (the latter produced in small amounts by standard reactors) being potentially used in nuclear weapons has prevented the widespread construction of breeder reactors and a number of moratoriums for such projects came into being.

Most of the problems occurring in areas such as Iraq caused by depleted uranium dust are related to children ingesting it from untreated drinking water that has become contaminated by UN/NATO forces spent ammunition.

The "military" aspect is also at the root of the public's biggest misconception about plutonium; that the radiation off of plutonium is the "strongest". Plutonium in fact gives off mostly alpha particles which can be stopped by shielding as weak as a piece of normal writing paper or the layer of dead skin cells that covers your body.

Plutonium is however very toxic and radioactively hazardous if ingested or placed on open wounds/etc.

http://www.vnh.org/BUMEDINST6470.10A/Plutonium.htm l

Something else that bothers me about everyone screaming bloody murder over the Yucatan and similar storage facilities is this bizzare belief by people that these materials are somehow magical evil concoctions that were given form in a lab. Most people honestly do not understand that uranium is mined from the ground like any other ore. And that the danger posed by nuclear waste is less one of radiation than of toxicity (radioactive damage stems mainly from consumption or absorbtion into the bloodsteam). The concept of shorter half-lifes being more radioactive also seems to elude people.

You are in far far more danger from walking into your house then you are from nuclear storage.

Most people in the US that are getting into a panic over relatively safe nuclear materials being stored in secure facilities many miles away are not even aware of how near they live to a superfund site. Most superfund sites revolve around heavy metals and other exceedingly toxic substances and are far more common than people think.

Nuclear power is (right now) one of the cleanest and safest power sources available. Too many people are stuck in some sort of a terrified cold war stupor and have been failing to do enough research.

And everyone reading this has to go read Zodiac

(Many poisons cause hallucinations, so getting rid of stomach contents when vision does not match other senses does have evolutionary advantage)