TEIF: Behind the scenes

cthia wrote:There has to be someone on the forum who has lived in Tornado Ally long enough to experience one. Storm shelter doors fail at the damndest of times. A lot of DIY projects are not sound. Even some professional projects have failed during a storm. So much so that the alarming evidence has initiated investigations. Do you suppose certain blast zones of a thermobaric weapon are equal to an F4 tornado? Do you suppose the Demon Murphy will ever lose his insane sense of humor?

The pressure drop doesn't kill you in a tornado. It's colliding with a debris cloud moving at 100 MPH, having the house collapse on you or getting dropped from a quarter mile up that does.

kzt wrote:

cthia wrote:There has to be someone on the forum who has lived in Tornado Ally long enough to experience one. Storm shelter doors fail at the damndest of times. A lot of DIY projects are not sound. Even some professional projects have failed during a storm. So much so that the alarming evidence has initiated investigations. Do you suppose certain blast zones of a thermobaric weapon are equal to an F4 tornado? Do you suppose the Demon Murphy will ever lose his insane sense of humor?

The pressure drop doesn't kill you in a tornado. It's colliding with a debris cloud moving at 100 MPH, having the house collapse on you or getting dropped from a quarter mile up that does.

But the energy of only an F4 has ripped off many a shelter door.

cthia wrote:But the energy of only an F4 has ripped off many a shelter door.

That's all very nice, but people are not buildings. Serious injury from over-pressure of an explosion is typical at 3.5 PSI. Death from direct blast effects starts at 1% at 14.5 PSI and his 99% at 29 PSI.

At 1 PSI frame houses are made uninhabitable. At 2 PSI the walls and roofs will tend to collapse. At 2-3 PSI cinder block and non-reinforced concrete walls shatter. 2.4 PSI is where you get 1% eardrum rupture, 12.2 PSI you have 90% eardrum rupture. At 3 PSI steel buildings pull away from foundations and distort. At 5 PSI most buildings collapse. At 10 PSI you have probably total building destruction, including reinforced concrete buildings. At 20 PSI even heavily reinforced concrete buildings collapse. (This is equivalent to a 500 MPH wind).

Having a 2x4 thrown through your chest will still kill you irregardless of the over-pressure. Having a car land on you will still kill you regardless of over-pressure. Having your roof collapse and crush you will kill you regardless of the over-pressure.

Jonathan_S wrote:Its vacuum should only last seconds total, and you don't need to take effective action to continue to survive that "vacuum" because it'll clear itself (by the returning inrush of displaced air reestablishing the pressure equilibrium) by the end of those few seconds.

Blast wave vacuum will not kill by oxygen deprivation. The issue is how fast it happens. If the external air is sucked away faster than the lungs can empty the airflow leaving the lungs tears them up and that is fatal. Against hard vacuum my memory is that you're ok (assuming you get back into air soon enough) so long as the hole in whatever pressure vessel you're in comprises no more than 1% of it's total area.

Of course you don't have to use purpose-made weapons as fuel/air bombs. Modern jetliners rammed into skyscrapers with most of their fuel loads still on-board do a great job of that....and the flaming result (as well as penetrating down the core etc of the building will also cause a blowtorch type updraft sucking air out of lower levers at a ferocious rate....difficult to breath.

And, yes, the Mesan Defense Forces using space launched kenetic weapons to bombard those stupendous office and residential buildings in the city would have had more than a trifling affect (so very much akin to blast waves) in the course of literally burning their way through the sky to "penetrate" to where the the Seccies were hold up.....but I digress.