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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

#111

Post by DuskStar »

ijpoijpoihpiuoh wrote: post #94
derefr wrote: post #49

Earlier quoted context omitted.

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 ag…

A large part of the reason that guns fell out of use on warships was that they were outranged by everything - guns that can shoot up to 40km (like those on the Iowa class) aren't enormously useful against destroyers tossing missiles from 200km or strike aircraft from a carrier 400km away. Guns that can shoot down planes and incoming missiles at 100km, though? That's pretty damn useful, even if it doesn't close the distance entirely vs missiles. As for why guns at all - well, guns tend to have magazine depths undreamt of by missiles, and railguns will likely follow that pattern. If moving to railguns for AA defence means you can shoot down 3 or 4 times as many incoming missiles for the same weight, that would be enormous.

And in the fog of war... Who's to say that a DD won't be able to close to railgun range of an enemy warship? Life's a lot easier when you can stay below the horizon, after all!

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

#112

Post by nradov »

ijpoijpoihpiuoh wrote: post #94
derefr wrote: post #49

Earlier quoted context omitted.

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 ag…

There are no hypersonic antiship cruise missiles deployed today. Some ballistic missiles have limited antiship capability and they do travel at hypersonic speeds but there are reasonably effective defenses against them now.

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

#113

Post by nradov »

SEJeff wrote: post #36
JudgeWapner wrote: post #6

Earlier quoted context omitted.

I listened to it and agree it sounds very childish. Better would have been to have some intelligent narration, the story in a nutshell. How much energy is required for a railgun? What uses do they have that cannot be done with conventional artillery? what were some of the major challenges faced by the R&D team? All of that could have been explained in the audio track that was instead used for crappy Michael Bay actio…

One of the problems with existing Navy "gun ships" is that explosive ordinance can be a hazard to sailors and has to be handled very carefully. Additionally, it has to be stored very carefully. One of the things a railgun hypothetically allows is launching non-explosive inert projectiles. What happen when you launch a big hunk of steel at something 200 miles away travelling Mach 6? Another huge benefit is the speed a…

Existing conventional munitions are absolutely used against surface and air targets.

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

#114

Post by mcguire »

1) "The system charges for two minutes..." One shot per two minutes is pretty bad; the current 5" gun shoots 16-20 rounds per minute.

2) "...at speeds up to Mach 6." One of the issues with old school, large caliber naval guns was that the blast from the guns would damage or destroy equipment near the muzzle. (I was just reading Pursuit by Ludovic Kennedy, about the British pursuit of the Bismark, and (IIRC) one ship (the Prince of Wales?) had its bridge windows blown out when firing the B turret "over its shoulder".) Is the shockwave from a railgun going to be similarly dangerous?

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

#115

Post by toss1 »

drewbt wrote: post #55
pageandrew wrote: post #40

Earlier quoted context omitted.

that's not how the world works

How does it work, how should it work, and what are we doing about it?

How it works now is that some percentage of the humans want to become, and/or want to support authoritarian rule. Authoritarian rule always wants to expanad, and will treat both it's subjects and other people as objects.

How should it work? Like eradicating smallpox, we'll need to somehow engineer, or teach, or by some other method, eradicate from the entire human race the authoritarian impulse.

Until then, the choices are: 1) submit, or 2a) create systems of laws & institutions to ensure that power remains distributed and is difficult to hijack/co-opt/capture by any one person or group and 2b) (since all systems are hackable/fallible) be prepared to fight for your freedom and the freedom of others less fortunate.

EDIT: add 2a

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

#116

Post by openasocket »

I've never quite understood why we need to change technologies so completely to get the projectile moving faster. As in, why couldn't we do the same thing by just making a bigger explosion in the barrel? I assume there's some point of diminishing returns or inefficiency that makes it impractical, but I haven't been able to find a source that gives the math to explain it.

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

#117

Post by asark »

openasocket wrote: post #116

I've never quite understood why we need to change technologies so completely to get the projectile moving faster. As in, why couldn't we do the same thing by just making a bigger explosion in the barrel? I assume there's some point of diminishing returns or inefficiency that makes it impractical, but I haven't been able to find a source that gives the math to explain it.

Explosives are really dangerous to carry around. Go looking through the fates of ships lost in WWI and II (last time there was a fair amount of ship combat going on) and there's an awful lot of "several rounds hit but everything was basically fine, except then one hit the magazine, blowing the ship in two and sinking her", or a fire starting and doing something similar, or a smaller cache of explosives readied for immediate use in a gun blowing up and causing massive damage, or whatever.

Not sure if that's the reason, but it's probably a reason.

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

#118

Post by WhyKill »

openasocket wrote: post #116

I've never quite understood why we need to change technologies so completely to get the projectile moving faster. As in, why couldn't we do the same thing by just making a bigger explosion in the barrel? I assume there's some point of diminishing returns or inefficiency that makes it impractical, but I haven't been able to find a source that gives the math to explain it.

Gas pressure just can't linearly accelerate something as efficiently as magnetic force can. You can get so much more velocity for the same barrel diameter instead of scaling barrel diameter and thickness because you have thrust being added through the whole length of the barrel instead of gas pressure being used to propel a slug at the end and then dissipating.

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

#119

Post by dogma1138 »

openasocket wrote: post #116

I've never quite understood why we need to change technologies so completely to get the projectile moving faster. As in, why couldn't we do the same thing by just making a bigger explosion in the barrel? I assume there's some point of diminishing returns or inefficiency that makes it impractical, but I haven't been able to find a source that gives the math to explain it.

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 WW2.

Those big guns are a bitch they are slow to reload and you can’t be anywhere near the muzzle including good couple 100 yards of the bow of the ship when those fire.

Also powder takes up space and weight, takes time to reload and it can explode when ignited.

Having a gun with parts that don’t explode intrinsically when set on fire is a pretty big advantage for any combat vehicle or vessel, not needing to carry propellant for your rounds is also a huge plus because you can carry more rounds or other munitions and supplies.

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

#120

Post by noir_lord »

openasocket wrote: post #116

I've never quite understood why we need to change technologies so completely to get the projectile moving faster. As in, why couldn't we do the same thing by just making a bigger explosion in the barrel? I assume there's some point of diminishing returns or inefficiency that makes it impractical, but I haven't been able to find a source that gives the math to explain it.

Space.

The propellant for a large shell takes up more space than the shell it fires, it's tremendously dangerous to have around from both accidents and enemy impacts.

Compared with a rail gun which is room full of exquisitely machined inert metal blocks.

Cost - Those inert machined metal blocks are cheap in a military if not absolute sense.

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