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It seems like hitting it directly is feasible, about would this not cause both entry & exit holes? I don't know how detailed the telemetry is/how damaged the tank is, but it seems like it would result in a slightly different failure than a single puncture.


I want to say there wouldn't be an exit hole if it met a bunch of liquid after entering. I think it would just disintegrate but there's not a lot of videos of guys shooting rounds into LOX/RP-1.


> there's not a lot of videos of guys shooting rounds into LOX/RP-1

What a job that would be--Elon tells you to get a slo-mo camera and start target shooting LOX at sniper distances "for research".


Many "non flammable" things burn in LOX. A recently-deformed bullet is hot. I expect it would burn fiercely.


Raufoss in Norway produce specialist explosive anti-materiel 12.7mm rounds that would be suitable, but they don't sell to civilians or even police forces.


Steel-core 7.62x54 would probably do it well enough. And you can buy that by the case, cheap.

All you would really have to do is get fuel dripping out along the surface to a point where it would ignite from heat from the engine exhaust.


Not even. LOX is explosive when it contacts organic matter like wiring harnesses, plus Dewars are very fragile, and breaking the vacuum would result in a lot of boil off.


I did not know this. So it's even easier than I thought to sabotage a rocket launch.

Thanks for replying--I would have gone to my grave not even considering the fact that rocket fuel has oxidizers mixed in, but the search you just sent me on set me straight.


It's not mixed-in, it's in a separate tank. But since the tank is an aluminum alloy (often with copper or lithium mixed in) these days, I wonder about its behavior in the presence of an ignition source (some magnesium in the bullet or perhaps even just friction?).


There's no Dewar vessel on the LV as far as I'm aware of. The surface of the stage is the propellant tank, made of simple Al-Li alloy, several millimeters thick. It works fine because of the large mass of the LOX and the comparatively short time of the stage's operation. You just can't transfer enough heat into the stage naturally in the short twenty or thirty minutes between fueling and launch to cause any trouble.

Before they started supercooling the LOX, it was even easier because heat transfer into LOX tanks is conventionally managed by boil-off (in launchers without supercooled propellants, latent heat keeps the liquid at a stable temperature and a trickle refills the tank continuously until a minute or two before launch).




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