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US Navy's Railgun Now Undergoing Tests in New Mexico

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Re: US Navy's Railgun Now Undergoing Tests in New Mexico

#91

Post by DuskStar »

derefr wrote: post #49
ChuckMcM wrote: post #44

I find the physics of rail guns pretty fascinating. For something nominally invented in world war 1 (1918) which is now "only a few years" away from possible deployment. We are talking literally a 100 years later. We went from powered flight to flying in orbit in less time, think about that. Is it a compelling weapons concept? Of course it is, you don't need explosives to shoot things that is pretty huge. Are wars ba…

It's not like the technology behind railguns hasn't been stable and ready to use for decades now. It's just that, until the more recent invention of ancillary technologies like supercapacitors, it's been so costly to fire them that there was no logical place for them on the battlefield, so we never bothered to operationalize them.

The materials science that goes into making rails that last for more than a handful of shots at useful velocities is pretty advanced, too.

Re: US Navy's Railgun Now Undergoing Tests in New Mexico

#92

Post by hanniabu »

deweller wrote: post #16
alistproducer2 wrote: post #10

Am I supposed to celebrate the spending of untold billions on an unnecessary weapon of death while my Bridges and roads crumble, my health care system sucks and absolutely nothing is being done about, or to prepare for, climate change?? I'm not impressed

Is there a widespread lack of funding for bridges and roads infrastructure in the US? The bridges and roads around me in middle TN are well maintained. These are funded by local government resources, right?

Yes, lack of funding plus poor planning. In my town it seems that every time a road is newly paved, 2 months later they're tearing it up to do some utility work, then after a single winter season it's back to how it was with potholes everywhere.

Re: US Navy's Railgun Now Undergoing Tests in New Mexico

#94

Post by ijpoijpoihpiuoh »

derefr wrote: post #49
ChuckMcM wrote: post #44

I find the physics of rail guns pretty fascinating. For something nominally invented in world war 1 (1918) which is now "only a few years" away from possible deployment. We are talking literally a 100 years later. We went from powered flight to flying in orbit in less time, think about that. Is it a compelling weapons concept? Of course it is, you don't need explosives to shoot things that is pretty huge. Are wars ba…

It's not like the technology behind railguns hasn't been stable and ready to use for decades now. It's just that, until the more recent invention of ancillary technologies like supercapacitors, it's been so costly to fire them that there was no logical place for them on the battlefield, so we never bothered to operationalize them.

To me, it's not entirely clear why we're bothering. Do we actually envision shore bombardment as a useful combat modality going forward? IIRC the types of ships that can mount this weapon are the same types that are currently vulnerable to hypersonic anti-ship missiles. All our potential equiv-tech adversaries have those, to my understanding. So wouldn't the railgun only be useful against lower tech opponents? And against such opponents, does it fill a substantial gap where we don't already have sufficient other tools?

Re: US Navy's Railgun Now Undergoing Tests in New Mexico

#95

Post by ben_w »

hanniabu wrote: post #89
Fej wrote: post #73

Why have coilguns not gotten the same amount of attention as railguns?

Does a coilgun have any advantages over a railgun?

Amateur railgun builders comment about the projectiles welding themselves to the rails; that certainly doesn’t happen in a coilgun. I think there’s also a big problem with supplying extremely high currents, which you can circumvent a bit in a coilgun by having more turns of wire.

Re: US Navy's Railgun Now Undergoing Tests in New Mexico

#96

Post by PhasmaFelis »

qball wrote: post #66
pneill wrote: post #51

Does anyone know why there is a flash of light and a puff of smoke when the gun fires? Since it's electromagnetic, you'd think you wouldn't see anything.

A railgun, while its mechanism is electromagnetic, works on a base level by causing a massive high-current electrical short. As a side effect (as in most electrical shorts), both the rails and some of the projectile are vaporized when the gun is fired due to both friction and electric arcing; and that's the smoke and fire you see. This wear (which is signifcant per shot) is also the main obstacle to actually using ra…

Why is no one developing coilguns? I've been wondering.

Re: US Navy's Railgun Now Undergoing Tests in New Mexico

#97

Post by charlesju »

ChuckMcM wrote: post #44

I find the physics of rail guns pretty fascinating. For something nominally invented in world war 1 (1918) which is now "only a few years" away from possible deployment. We are talking literally a 100 years later. We went from powered flight to flying in orbit in less time, think about that. Is it a compelling weapons concept? Of course it is, you don't need explosives to shoot things that is pretty huge. Are wars ba…

I think the interesting use case would be to put things into space for a lot less money. Imagine putting one or many of those new Space X internet satellites into a rail gun that goes straight up.

It doesn't need to go all the way into space, it just needs to get pretty high, then the cost to break into orbit can require a lot less fuel and make it a lot more cost effective to do space stuff.

Re: US Navy's Railgun Now Undergoing Tests in New Mexico

#98

Post by AnimalMuppet »

pm90 wrote: post #88
qball wrote: post #83

Earlier quoted context omitted.

Sure, but missiles have to propel themselves, are very large compared to railgun projectiles, and are easier to break apart by putting a heavy wall of lead in the air. Railgun projectiles have none of these disadvantages. They don't need propellant (or a warhead; the energy delivered upon impact is more than sufficient to break things without needing to explode), they're a solid projectile (and as such can't be as ea…

Could you hit a railgun with a railgun? Why wouldn't countries build massive anti-ship railguns to prevent any such ship from getting even close to their naval facilities?

> Could you hit a railgun with a railgun?

"Smaller than a missile". You could, but it's harder.

Re: US Navy's Railgun Now Undergoing Tests in New Mexico

#99

Post by NeedMoreTea »

minikites wrote: post #41
SEJeff wrote: post #37

Earlier quoted context omitted.

Really hard engineering pushing the limits of physics and materials science is fun, killing people is not.

Do you genuinely see the same virtue in the engineering of a bridge and the engineering of a cruise missile?

> see the same virtue in the engineering of

Actually yes, but the application of on the other hand...

Only a tiny few of the multiple conflicts since WW2 have been helpful or even justified. Many have been hugely counter-productive. Yet I can't deny that wars and military spending have given huge impetus to advance many capabilities. Capabilities that have ended up having huge applications in peacetime too. Whether rocketry or WW2's improvement of the cavity magnetron, or early computers. Who knows how many decades later some of the stuff we take for granted might have arrived, or sat on a dusty shelf as interesting but impractical or non-commercial? Even the humble tin can got its start supplying food to the navy, in the age of sail.

Re: US Navy's Railgun Now Undergoing Tests in New Mexico

#100

Post by DuskStar »

SEJeff wrote: post #78
minikites wrote: post #68

Earlier quoted context omitted.

There's no way other than weapons engineering to make those discoveries?

In the same vein, as an industry, pornography really improved computer storage density and video codecs whereas electronic trading really improved the tech to reduce networking latency. Virtually all engineering benefits from other engineering that came before it. There are plenty of other ways, but this is how it is. Most all of what NASA does or has ever done has directly benefited the Department of Defense. Does t…

> Most all of what NASA does or has ever done has directly benefited the Department of Defense.

Especially since a lot of the benefit has gone the opposite direction a lot of times - how many of our space telescopes started life as extra reconnaissance satellites?

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