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Comment by pests | Hacker News Reader

> turning all organic matter to ash

Is this actually true? I see it being repeated everywhere but there is a lot of mass in a human body. Can 100 milliseconds of "ignition" (as you put it) really burn off all of that?

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I am no expert on any of this but was curious. So I entered some guesstimates in online calculators. Assuming they were at 12,500 ft / 3810m we get a pressure down there of 5546 PSI / 382 Bar. Compressing the air in the cabin from roughly atmospheric pressure to 382 Bar would heat it to above 1300°C, or 1600°F. As far as I understand, in milliseconds. That’s a lot of heat energy. The water around them will absorb some of that, but they‘d be toast.

That doesn’t seem nearly hot enough to burn bodies before the water takes the place of all that hot air.

Do the bodies themselves get hot from being compressed? I’d assume largely no with our water content.

Think of it like a shock wave passing through the cabin and everything in it in time measured in milliseconds. Everything gets very hot basically instantly on the other side of that wave. Water less than gas, I’m too lazy to figure out what would be expected to exactly happen to water, but it would definitely be between getting hot enough to kill and disassociating to elemental hydrogen and oxygen gas. The question is what does a 6000 psi step function look like as it propagates through water.

Having gotten hit on the head in a low speed car accident I wouldn’t worry at all about the suffering through the actual implosion. The speed of the shock wave would be much faster than nerves conduct information.

No, it is not true at all. Heat conduction velocity is independent of the temperature gradient. It would only affect a very shallow layer of the skin.

The gas can heat to thousands of degrees but there isn't much energy in it. It wouldn't do much damage by itself.

The sudden change in pressure causes the majority of the destructions through purely mechanical effects.

A truly HN discussion -- what percentage of the occupants would be ash and what percentage of the occupants would be molecularly sheared viscous people fluid that rapidly disperses. The oxygen tank would rupture and provide an ignition source too.

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