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The US Navy's Railgun Program
RougeFive writes "Imagine a warship weapon that can launch projectiles at Mach 10 without explosives (more than three times the muzzle speed of an M16 rifle), that has a range of 220 miles and that uses the enormous speed to destroy the target by causing as much damage as a Tomahawk missile. Meet the U.S. Navy's electromagnetic railgun program."
Why is the summary written like we haven't heard about this before.
http://tech.slashdot.org/story/10/12/11/046205/navy-tests-mach-8-electromagnetic-railgun
http://tech.slashdot.org/story/12/02/08/152224/us-navy-receives-first-industry-built-railgun-prototype
In and of itself.. this article is very lacking and at face value is old news. We have been developing railguns for a long time. We have the principles down, but the problem comes with the energy needed to really run a weapons effective version.
Even the linked article just referrences an overview of the technology and it's goals. Why not an update... did they make a breakthrough? SOMETHING...
Well... they need to drive interest since they just laid off some 160 people from their West Chester, Ohio plant.
http://www.wcpo.com/dpp/news/region_north_cincinnati/west_chester/bae-systems-to-lay-off-about-160-employees-at-west-chester-site
I know about this since I live very close by.
Say it ain't so!
Hey look Ugg. Your club hurts, but I added a rock to the end of mine. Oh yea, well I have made a thinner club with a pointy edge to it so I can throw it at a distance. Oh yea. I put a sharp stone at the end of it so it will cut into my enemy further (and yes it has hunting applications too).
oh yea. Well I now can launch it with an other stick.
Heck I beat you with a more compact stick on a string.
By the way I have found to put sharper rocks at the end of sticks...
Hey check this out I found out how to melt rocks into this shiny stuff that doesn't shatter like a rock does, and I can grind it to make it sharper.
Yea I took your idea and made mine longer.
Yea, Well mine is sharper and better balanced.
Hey I just came back from China, I found this neat stuff that explodes.
Yea. I found I could make the direction better if I encase it metal that can contain and direct the explosion.
Well mine is bigger.
Well mine is more portable.
Well mine is more accurate.
Well mine can reload faster.
Well mine I can mass produce.
Well my big ones explode more.....
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
Wonderful! First our video games are on rails. Now our guns are.
Shai Schticks:"You don't make peace with friends, you make peace with enemies"
The power source is now a black hole. Oh wait! Skip the gun and throw the black hole at the target.
Shai Schticks:"You don't make peace with friends, you make peace with enemies"
Articles on these types of "futuristic" technology projects so rarely take the time to explain the challenges involved in making it a viable tool. This article did. That was refreshing.
You missed one MAJOR feature: cost.
New warfare is going to be all about cost. Nations/organizations battling on a ROI factor.
Case in point - Al Qu--whatever. They got a lot of dipshits who will die for Allah or whatever and they're giving the US a run for their money in those shitholes they're fighting in.
The US has all this high tech hardware that's been proven almost useless - the DRONES are being proven USEFULL.
You got a $190,000,000 aircraft? I got a 10 $10,000,000 aircraft that has a BETTER chance of shooting down the entire squadron of the $190M aircraft. You got ONE F-22 and a bunch of F-15s? So? I got 20+ Migs with assholes who'll die at any means to take YOU out.
And live to see another day.
President Eisenhower wasn't so far off (military industrial complex stuff), but he missed the fact of many many very poor people pissed off at the US for various reasons - and they'll die to hurt us.
People don't get it. They don't. Mitt RMoney is a moron. Obama sort of gets it.
""Imagine a warship weapon that can launch projectiles at Mach 10 without explosives..."
Well, that's not counting the railgun itself, I guess.
They tend to fail spectacularly.
No, speed^2 * mass = kinetic energy.
You keep using that word. I don't think that word means what you think it means.
Not talking about rail as in railroad...
It was in the movie.
===== Murphy's Law is recursive. =====
BAE doesn't give a fuck, they have more than enough government connections.
"Railgun" pieces, however redundant, get page hits.
"This post is an artistic work of fiction and falsehood. Only a fool would take anything posted here as fact."
vs. Railroad Gun
Really?
Everything is better with chainsaws.
Do you know what happens when you launch something with that much energy into something solid, like the ground? It stops. That energy has to go somewhere.
Support my political activism on Patreon.
And how do we currently get into space? Oh right, via that other tech that started as a long-range weapons system.
Everything is better with chainsaws.
For their own good maybe.
I don't know how much they care about others considering they are ok with dumpi^wshooting depleted uranium on others soil.
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
Speed of sound: about 1100 feet per second.
Muzzle velocity of an M16: about 3200 feet per second. So, close enough to Mach 3 to call it that, with rounding.
5.56 NATO rounds (typical for an AR-15 or M-16) top out at around 2,900 feet per second for standard pressures and barrels. Most are somewhat under that for various reasons. At sea level, speed of sound is about 1,100 feet per second.
So, yeah, 3 times is a rounding point "ballpark" number for 2.7 times the speed of sound or so.
So, "since forever"
If I point the rail gun straight up, how high can it launch one of it's projectiles?
No reflection at all about the deep problems that our obsession with inflicting violence on other people has got us into.
If all-holy technology is used to build a bigger, faster something - even if it's a terrifying weapon in the hands of a murderous empire like the US - then slaver over it on Slashdot. Because its about technology, and its about the gunz, and it has to be cool.
Since when US army gives a crap about collateral damage ?
Can't wait until Eve Online nerfs this railgun, too.
And you can only mount 6 of 'em, or 5 and one platform for a guy with a machine gun to stand on to shoot rafts with guys with handguns that get too close. Which you need or the handgun raft will pew pew you while it drags your 100,000-ton battlrship to a halt with a rope and 7.5 hp Evinrude.
Gotta love game "balance" and "rock-paper-scissors" design.
(-1: Post disagrees with my already-settled worldview) is not a valid mod option.
Who needs nukes when you can hurl big rocks at an enemy through a mass accelerator.
it's not really clear if you are saying this is a good or bad thing. it's good in that there's no radiation, so it damages the target and the target only (if it hits), not the rest of the world for decades. the bad thing is that fact might make it see a lot more use than nuclear weapons.
Its called politic when you are in charge of a superpower, trolling when your on a forum kidding around. go figure
---Saying gnome 3 is better than windows 8 not so much a compliment as it is damning with light praise.
It worked pretty well but it only did 100 damage. A tomahawk probably does more.
Or another Hood? Or new Dreadnoughts?
See the problem? You're just reviving an old paradigma with all its old weaknesses - plus lack of any visual confirmation of hits whatsoever because you're firing way beyond the horizon, plus much longer time of flight due to distance. Accuracy just won't materialize in any way whatever, so you'll end up blanketing an area hoping to hit something sooner or later. If it's a moving target - forget about it.
You can't hit an object 220 miles away surface to surface by firing in a straight line. There's a big ball of rock and water in the way. If you have to fire in a balistic arc, is the high velocity of a rail gun of much use?
Better than speaking big and carrying soft sticks.
For large sets, this will be our guide even unto death, for the LORD will work for each type of data it is applied to...
Since the muzzle velocity with standard issue ammo is ~950 m/s which is within spitting distance of 1,021 m/s.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
Who needs nukes when you can hurl big rocks at an enemy through a mass accelerator.
it's not really clear if you are saying this is a good or bad thing. it's good in that there's no radiation, so it damages the target and the target only (if it hits), not the rest of the world for decades. the bad thing is that fact might make it see a lot more use than nuclear weapons.
That's because I'm not sure. Dropping rocks from orbit would be a good last option to have I suppose. But it's pretty damn indiscriminate and will certainly kill a lot of civilians. That's pretty much how I feel about developing this kind of tech. It would be good to have if it's needed, but I hate the thought of what it means if it does get used.
Whatever you try to launch into space with a rail gun will melt before it gets out of the atmosphere.
Two problems I see with all this.
First is that in order to hit something 220 miles away you are going to have to shoot the projectile in a ballistic arc over the horizon. Air resistance will be a serious issue at this distance if you take the low path because Mach 10 at the gun will be significantly lower 110 seconds later when the projectile is still in flight. I'm guessing you would be advised to not depend on kinetic energy for all your damage at long ranges.
Second, where the projectile came from will be painfully obvious by following the ballistic track back to it's origin. A Tomahawk can be programed to change course and obscure where it came from.
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
If you want it to stay in space it needs a rocket engine. Launching rockets off rail guns is a bit more complicated than launching pointy bits of metal.
Where is the 'space nutter' grouch when we need him?
John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'
Imagine a warship weapon that can launch projectiles at Mach 10 without explosives
its offtopic but No. just, hell no. Every slashdot story about war-tech needs to have an icon of dick cheney, then perhaps we would begin to understand that every advancement in the american arsenal is diametrically opposed to the idea of technology as a whole, which is to make life better.
imagine a land where violent crime, grinding poverty, intractable inequality, and disease are a part of everyday life. its a nation with a standing debt of around sixteen trillion dollars, and it can think of no better use of its time or limited remaining resources than to invent a superweapon for an enemy that does not exist, to defend the collective interests of a handful of elites.
Good people go to bed earlier.
I would be more interested in ANY home brewed project that can throw a projectile the weight of the bullet in a 5.56 Nato round at the same velocity as that round.
That is 62 grains at 3100 ft/s or for you enlightened beings in the EU 4.02 grams 945.5 m/s
Then an article on how it's been 3D printed. :-D Bonus points if the coils are 3D printed inside the plastic extrusion.
There is no limit on size, I don't care if it uses a 30 farad starwars capacitor bank or coils the size of a farfergnuggen.
I'd go on a Vegan diet but the delivery time from Vega is too long. --brownkitty
Imagine something useful, like a communications satellite, you'd want to place in orbit. Maybe it weighs 100kg. Now imagine crushing it with a 12,000,000kg weight. That's sort of what happens when you try and accelerate it at 1,200,000m/s/s. Also of note, escape velocity is 11,200kph. Mach 10 may be slightly faster than that, but shooting something at 11,200kph will only make it out of Earth's gravitational pull if friction is not taken in to account. You need to factor in 160km of atmosphere causing friction.
My fault. I shouldn't have replied so quickly. Actually, I didn't think he was pointing out differences as much as I thought he was mocking the comparison I'd made, which did tick me off. In the end, they are vastly different. My apologies.
No, it is 1/2mv^2
Never answer an anonymous letter. - Yogi Berra
hurling big things is wimpy compared to nukes. 10,000 kg projectile going mach 100 = 1 measily kiloton equivalient. here's a quarter kid, get yourself a thermonuclear weapon.
A simple sling system will achieve the necessary projectile speed you want. Set up a 3600rpm motor with the axis vertical. Attach a 2.5 metre long steel bar to the shaft and a counterweight on the other side, or use a 5m long bar mounted in the middle. Put your bullet on the end of the bar with some kind of remote-controlled hold/release device but remember it will be under considerable load from the centripetal forces.
Spin up the motor until it reaches its max rated speed, 3600 rpm. Air resistance etc. will be a problem but a big motor rated at a couple of kW should do the job if the bar is thin or profiled aerodynamically. At that speed the velocity of the end of the rod and the bullet will be about 900 m/s. Release the bullet and it will fly off. Where it goes depends on which point in the rotation you release it.
Note that this would work for any bullet size and weight -- .223, .50 BMG, 20MM cannonshell, 23mm DU penetrator etc. A mechanism to feed a stream of projectiles down the axis of rotation and along the arm into a suitable hold/release "breech" would turn it into a continuous-fire system at a rate of up to 3600 rounds per minute. Assuming a 5m double arm then this rate could be doubled to 7200 rpm.
A gearbox and higher rotational speed would allow the use of a shorter sling arm while maintaining the final projectile velocity although air resistance would become more of a problem.
A gasoline engine could be used to drive the slingshaft if electrical power is not to hand, or it could even be human-powered via pedals for a low-tech Mad Max scenario (possibly with a flywheel attached).
that would one very, very long gun. hundreds of miles long: think of how many miles a rocket with human crew is under acceleration. That gets you into Newton's "cannon on impossibly tall mountain" scenario to achieve orbit (though it's difficult to avoid the stable orbits that smack back into the tall mountain, or very difficult to achieve trajectory in earth-moon system that can achieve orbit)
I'd rather offend everyone and carry a gun.
... they are, after all, just a bunch of weirdly drawn cartoons... I know the white man-toddlers... like to call it "anime"... they are cartoons. For kids.
You do know that it is the Japanese who call it anime and that anime is short for animation so yes... by definition of the word "anime" they are cartoons. Good attempt to try and attribute the anime term to white fanboys.
Oh, I don't even watch anime, but people enjoy it so why be a douche about it.
Actually, a huge tank of fossil fuels contains a tremendous amount of energy, this is how the world economy works. When I first read about the naval railguns, 7 or 8 years ago, there was no talk of nuclear propulsion. You need a lot of energy to move the ship in the first place, nuclear or not. The design was for a cruiser or destroyer ship, with electric propulsion. When firing, you divert the huge power that would have gone to the propelers otherwise, and charge the supercapacitor banks.
If you send a ton of pointy object at those speeds, the 1/2 mv^2 of that object is large relative to air resistance. Also, they presently do have bullets for large caliber weapons that can change direction during flight. Not as much as a missile, but significantly.
It's easier to be a result of the past, but more fun to be a cause of the future! http://www.spacefinancegroup.com/
From some of my earlier reading, one of the big advantages is the elimination of a huge, expensive and unreliable supply chain to provide explosive ammunition and missiles to the ships, and elimination of the biggest threat to military ships, the penetration and explosion of the ammunition in the ship. With rail guns you have only to supply electrical power (typically from nuclear reactors that are already big enough to supply the juice), and inert metal projecticles. The projectiles are much cheaper than cannon rounds and much, much cheaper than Tomahawks ($600,000 each). There are various other advantages and disadvantages for each weapon, but manufacturing, assembling the explosives and other components of 1000 1/2 ton cannon shells, and delivering them to a carrier or destroyer at a top secret location in the middle of an ocean in unpredictable weather can't be easy. With railguns and nuclear power a surface ship is good to go as long as the food and the tungsten pellets (inert, safe-until-fired ammunition) last.
It's easier to be a result of the past, but more fun to be a cause of the future! http://www.spacefinancegroup.com/
After that Venezuela, and after that, rest of the non-NATO world?
Like Vietnam?
I've got better things to do tonight than die.
Doing it from a ship or land based gun will give you problems because the Earth has this curvature, and your hypersonic dart is pretty much going to travel in a straight line. So things that are over the horizon are pretty much out of reach since drilling straight through the Earth is not really practical.
These projectiles will certainly be guided (http://www.popsci.com/technology/article/2012-08/its-experimental-rail-gun-navy-wants-gps-guided-hypersonic-projectiles) with accuracies at least as good as current ICBM systems, and probably as good as existing precision bombing systems like JDAM (http://en.wikipedia.org/wiki/Joint_Direct_Attack_Munition) and others. There are plenty of ways to guide a very fast munition that do not require sticking control surfaces out in a hypersonic air stream.
I'm wondering if the accuracy of these things is better or worse than a conventional shell. I'm thinking worse. At first blush one thinks, well it's faster so it must be better since wind velocity is less.
But let's do some calculating. Since this is a kinetic energy weapon you have to fire it at full velocity to achieve the full energy delivery. For any given range that you could hit with a conventional heavy explosive shell the faster to fire it the LONGER it takes to arrive. The reason for that is that you have to fire it increasingly upward to limit the range as you fire it faster. Thus it takes longer and longer to reach the target and the horizontal velocity gets lower and lower. Thus wind has a longer time to act on it.
Additionally the shell is lighter weight and it is going higher in the atmosphere were the wind velocity increases. So this makes the defelction even worse. I suppose at some point this thing gets to negligible atmosphere and it stops getting worse.
But it seems to me that as long as we require the kinetic energy then were stuck with a less accurate system for any conventional shell range. Of course for ranges beyond conventional then this is the only way to get there.
Some drink at the fountain of knowledge. Others just gargle.
I hurt myself being bored with this post civil war, pre-1900s claptrap.
I'd go on a Vegan diet but the delivery time from Vega is too long. --brownkitty
Another thing who that can kill people who probably didn't have it coming. But hey, THAT'S the shit that's important.
No, one half of speed^2 * mass = kinetic energy.
I'm sticking with the Wave Motion Gun.
No good deed goes unpunished.
Conventional weapons, like rifles and shipboard guns, will continue to accellerate a projectile the entire length of the barrel ... at least until the velocity of the project matches that of the expanding gases (which, slow as they expand).
Contrast this to a railgun which does not depend upon expanding gases to provide the force to accellerate the projectile. The projectiles are limited only in their ability to withstand the accelerating forces (which, are electromagnetic in nature - Lorenzian forces) and friction when they exit the barrel of the railgun.
The advantage of a rail gun is that explosives typically aren't needed (but, very high electrical current in a very short pulse) to "fire" the weapon and that an explosive charge is not required by the projectile to do its damage - the damage is inflicted solely by the kinetic energy of the projectile hitting the target.
The disadvantage is that due to the high power that is required, the rails can be warped by the high currents and forces involved and the trajectory of the projectile is flat. This is fine if your weapon is mounted high (so as to see over the horizon) or you can see your target. Conventional projectiles follow a more standard ballistic trajectory (sort of like a parabola that is "scrunched" as the projectile approaches the target (i.e. leaves the barrel and a lesser degree angle than the approach angle towards the target). This may make railguns a bit out of place for typical NGFS (Naval Gun Fire Support) applications.
If you're gonna use THAT much energy, and plan to (are able to) fire more than once, why not just nuke it from orbit?
:)
All funnies aside, seriously though, i love the idea of a rail gun, but all the energy needed to use it once would make it
only reasonably useful if it was MASSIVE, and in an extinction level event.
In my country, we have silos FILLED with conventional arms that are more efficient, and through their development, maintenance and storage,
have a significant bit of our economy locked up. (In the US we need everything more than we need more weapons imo, use it for science
If you send a ton of pointy object at those speeds, the 1/2 mv^2 of that object is large relative to air resistance. Also, they presently do have bullets for large caliber weapons that can change direction during flight. Not as much as a missile, but significantly.
At mach 10 wave drag will be fairly high as energy is taken to generate shock waves and heating will be significant. As you point out making the projectile heavy in relation to it's cross section does improve drag, but over a flight time measured in hundreds of seconds the net effect will be that the projectile arrives at a speed much lower than Mach 10. As this is a kinetic energy weapon, the arrival speed is of extreme importance, although a telephone pole sized metal projectile is going to mess up some stuff even at Mach 1 Problem is, I don't think one will easily get a rail gun to launch a 1 ton object of any shape due to the amount of energy this would require. (Which is why we use explosives to do this sort of thing now, lots of energy in an itty bitty package.)
Bullets that change direction are not that common. DARPA does have some laser guided dart things that might be usable for that, but I'm thinking a guided missile is just going to be cheaper way to get the same effect. They also have the added bonus of not requiring huge power plants, can carry multiple types of warheads, and can be launched from all sorts of platforms.
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
they are cartoons. For kids.
Please tell me you've never rented Ninja Scrolls or Afro Samurai for your kids to watch...
He's making a joke about the movie "Eraser" where the bad guys were armed with "portable railguns" (at one point die governator is shooting one from each hand) that somehow can fire rounds accelerated to a tenth or so of the speed of light, can fire multiple times per second, for several minutes, without reloading/recharging, that knock someone back 50 feet on impact, and yet somehow there's virtually no recoil for the use of said device.