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The SR-71's predecessor used cesium-laced fuel to create radar-absorbing exhaust

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Re: The SR-71's predecessor used cesium-laced fuel to create radar-absorbing exhaust

#141

Post by UnFleshedOne »

mnw21cam wrote: post #115
jabl wrote: post #79

Earlier quoted context omitted.

Apparently back in the day they were seriously considering ClF5 as the next generation oxidizer for rocket propellants. Implying that the rocket exhaust would to a large extent consist of HF and HCl. Yikes!

ITYM ClF3 (Chlorine Trifluoride) which earned the now famous description "hypergolic with test engineers". https://blogs.sciencemag.org/pipeline/archives/2008/02/26/sa... Equally funny is where someone thought that it would be a wonderful idea to burn mercaptans in a rocket, which wasn't quite as toxic, but caused the test site to become a no-go zone just from the unbearable stench.

Stench on toxic substances is a feature, not a bug :)

Re: The SR-71's predecessor used cesium-laced fuel to create radar-absorbing exhaust

#142

Post by DuskStar »

regularfry wrote: post #54
DuskStar wrote: post #41

Earlier quoted context omitted.

> Same line of thinking that results in depleted uranium tank shells. Yeah, since neither was particularly toxic, and both offered significant performance gains over the alternatives. (Uranium is extremely dense, self-sharpens on impact instead of mushrooming, and catches fire after penetration giving you an incendiary payload for free. Supposedly, nothing else comes close for tank rounds)

Uranium is... not nice stuff. I wouldn't classify it as "not particularly toxic". https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2819790/

Perhaps I should have said "not outrageously toxic" or something of that sort, because that does not sound worse than the stuff we make normal bullets out of - lead.

Re: The SR-71's predecessor used cesium-laced fuel to create radar-absorbing exhaust

#143

Post by astine »

regularfry wrote: post #54
DuskStar wrote: post #41

Earlier quoted context omitted.

> Same line of thinking that results in depleted uranium tank shells. Yeah, since neither was particularly toxic, and both offered significant performance gains over the alternatives. (Uranium is extremely dense, self-sharpens on impact instead of mushrooming, and catches fire after penetration giving you an incendiary payload for free. Supposedly, nothing else comes close for tank rounds)

Uranium is... not nice stuff. I wouldn't classify it as "not particularly toxic". https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2819790/

True, but the alternative is tungsten, which is not much better in terms of toxicity:

https://www.atsdr.cdc.gov/toxprofiles/tp186.pdf

The problem here is that armor piercing rounds need to be made of heavy metals in order to work and heavy metals are generally toxic. Even lead, which old fashioned bullets and shells are made of is toxic.

Re: The SR-71's predecessor used cesium-laced fuel to create radar-absorbing exhaust

#144

Post by DuskStar »

jacobush wrote: post #121
jabl wrote: post #76

Earlier quoted context omitted.

Several western countries use tungsten instead of DU. Apparently largely due to the political issues anything uranium brings.

If you call “toxic” and non biodegradable “political”, I agree with you. I think you will find that countries that expect the fighting to be largely in their backyard selected Tungsten and the countries that fight “overseas” selected Uranium.

And yet all of them also selected lead for their infantry weapons, which is similarly toxic.

Re: The SR-71's predecessor used cesium-laced fuel to create radar-absorbing exhaust

#145

Post by regularfry »

DuskStar wrote: post #142
regularfry wrote: post #54

Earlier quoted context omitted.

Uranium is... not nice stuff. I wouldn't classify it as "not particularly toxic". https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2819790/

Perhaps I should have said "not outrageously toxic" or something of that sort, because that does not sound worse than the stuff we make normal bullets out of - lead.

Lead doesn't shatter the way uranium does, so it's less inclined to form a breathable dust on impact.

Re: The SR-71's predecessor used cesium-laced fuel to create radar-absorbing exhaust

#146

Post by jacobush »

DuskStar wrote: post #144
jacobush wrote: post #121

Earlier quoted context omitted.

If you call “toxic” and non biodegradable “political”, I agree with you. I think you will find that countries that expect the fighting to be largely in their backyard selected Tungsten and the countries that fight “overseas” selected Uranium.

And yet all of them also selected lead for their infantry weapons, which is similarly toxic.

Ah, yes, because all lead bullets turn into a thousand degree cloud of dust, which you can later accidentally inhale or adsorb through your skin decades afterwards.

Re: The SR-71's predecessor used cesium-laced fuel to create radar-absorbing exhaust

#147

Post by regularfry »

astine wrote: post #143
regularfry wrote: post #54

Earlier quoted context omitted.

Uranium is... not nice stuff. I wouldn't classify it as "not particularly toxic". https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2819790/

True, but the alternative is tungsten, which is not much better in terms of toxicity: https://www.atsdr.cdc.gov/toxprofiles/tp186.pdf The problem here is that armor piercing rounds need to be made of heavy metals in order to work and heavy metals are generally toxic. Even lead, which old fashioned bullets and shells are made of is toxic.

Uranium is more likely to distribute that toxicity in a convenient dust cloud, though. Tungsten and lead for the most part stay in one piece on impact.

Re: The SR-71's predecessor used cesium-laced fuel to create radar-absorbing exhaust

#148

Post by acqq »

ufmace wrote: post #109
acqq wrote: post #96

Earlier quoted context omitted.

> The world is now in the longest stretch of world-wide peacetime ever in history. Peacetime where? There was constant war since WW II mostly directly or indirectly waged by the US.

Peacetime everywhere. The post-WWII wars are all tiny by comparison. The nuclear era is historically unprecedented in the total lack of direct warfare between major industrial powers.

Check your history books about the time before WW I and between WW I and WW II. Both periods are completely comparable with this now.

It was the “common knowledge” that the big war “can’t happen”.

“Everywhere” in your answer means for you. Ask the families of dead soldiers about “everywhere” or the millions of people outside the of the US whose relatives died in wars or even only due to the US sanctions which are how the US prepares for its next war (like in Iraq).

Re: The SR-71's predecessor used cesium-laced fuel to create radar-absorbing exhaust

#149

Post by DuskStar »

regularfry wrote: post #145
DuskStar wrote: post #142

Earlier quoted context omitted.

Perhaps I should have said "not outrageously toxic" or something of that sort, because that does not sound worse than the stuff we make normal bullets out of - lead.

Lead doesn't shatter the way uranium does, so it's less inclined to form a breathable dust on impact.

That's true! Lead does tend to stay more clumped up than uranium dust. But isn't it also easier for lead to become bioavailable and/or enter the water supply?

Re: The SR-71's predecessor used cesium-laced fuel to create radar-absorbing exhaust

#150

Post by dang »

throwawaynihil wrote: post #86
manigandham wrote: post #56

Earlier quoted context omitted.

These recon and offensive capabilities have in fact led to a more peaceful world. It’s the harsh reality that we live in.

Your idea of peace: America rulez! Every1 3ls3 is 3nslav3d!!!$@!$@$

We've banned this account for repeatedly violating the site guidelines.

https://news.ycombinator.com/newsguidelines.html

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