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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

#151

Post by Zelizz »

UnpossibleJim wrote: post #134
dogma1138 wrote: post #119

Earlier quoted context omitted.

To make a bigger explosion you need a bigger barrel and more powder charges. Eventually you hit a limit where you simply can’t create enough pressure to propel the projectile faster and not turn the barrel into a pipe bomb. For the most part many guns have already hit their practical limit in this regard. There is a good reason why battleships fell out of favor other than the US being the only blue water navy after W…

It isn't only that, with a powder charge you are pushing the projectile with an explosion. That explosion will also cause a disturbance on a ship, until you get to a pretty enormous size, you have to calculate that into your trajectories. With a railgun, you have a series of magnets pulling a projectile forward incrementally faster. It's a lot less energy wasted into the environment, meaning a lot less energy put bac…

What you are describing is a coilgun, a railgun uses a slightly different principle.

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

#152

Post by darkpuma »

toomuchtodo wrote: post #34
doctorRetro wrote: post #12

Earlier quoted context omitted.

I agree on at least the first half of your statement. Although I'm not sure I'd say 'delusional' as much as - I don't know? - Jingoistic? Bombastic? I feel like I should be playing Command and Conquer to that sound track. At the end of the day, these are killing machines that are being designed to take human lives, and it does feel more than a bit inappropriate. I think that's what you're getting at with the latter h…

A friend overlaid an EDM track (Flux Pavilion if I recall) on the original test fire videos from several years ago when the prototype was located at the Virginia test site. I enjoyed the short piece of creative they remixed in the same way I enjoyed the Iron Man franchise. It’s a killing machine, but the engineer in me still deeply appreciates the advanced technology these systems are based on (energy/thermal managem…

> "SpaceX vehicles are a firmware update away from being high precision ICBMs"

While strictly speaking true, as an ICBM booster the Falcon 9 would be going on 6 decades obsolete. Cryogenic propellants for ICBMs have been obsolete since the early 60s.

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

#154

Post by crimsonalucard »

jiveturkey wrote: post #109

No mention of China. I wonder if the revival of this is due to China's railgun developments.

I find this invention will solve our problems. Just point at China, fire the gun, and all problems solved.

Just kidding, seriously what do we point it at? And what problem will it solve after it's been fired?

Also why are we not competing on high speed rail technology? Why do we always have to beat a country with military technology given how completely useless most of it is.

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

#156

Post by hanniabu »

ben_w wrote: post #95
hanniabu wrote: post #89

Earlier quoted context omitted.

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.

Interesting, makes me want to see a chart with the pros and cons of both. There's gotta be a reason they chose to go this route.

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

#157

Post by fnord77 »

I wonder how durable these will be in combat

Seems vulnerable to damage during a battle. A couple stray bullets or shrapnel hitting those power cables would put it out of commission unless it was heavily armored.

where as they would just ping off an old-timey cannon harmlessly.

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

#158

Post by keiru »

lm28469 wrote: post #153
dfilppi wrote: post #140

Get the projectile up to mach 33 and it can shoot satellites out of orbit from the ground.

Making a satellite capable of surviving the launch will be the second part of the problem.

"shoot satellites out of orbit", not "into orbit"

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

#159

Post by crimsonalucard »

grenoire wrote: post #144
semi-extrinsic wrote: post #128

Earlier quoted context omitted.

Nitpick on 2 a): you can't turn water vapor into steam, water vapor is steam .

Is it really that humidity in the air is classified as steam?

No steam references entropy or distribution of the molecules in the air. Concentrated water molecules visible as myst produced from hot water is steam. The water molecules evenly dispersed in the air is humidity.

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

#160

Post by russdill »

fnord77 wrote: post #157

I wonder how durable these will be in combat Seems vulnerable to damage during a battle. A couple stray bullets or shrapnel hitting those power cables would put it out of commission unless it was heavily armored. where as they would just ping off an old-timey cannon harmlessly.

old-timey cannons need a lot of systems to slew/aim/etc. And without these systems, they are useless.
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