The US Navy's Railgun Program

Is this news? by Anonymous Coward · 2012-10-01 08:21 · Score: 4, Informative

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

Re:Is this news? by rahvin112 · 2012-10-01 11:19 · Score: 5, Interesting

Anti-Ship missiles are a bunch of hooey. Yes they are fast and damn hard to shoot down, but if you are are within range of one those with your navy you are doing it wrong. Oh yes, there are people in the USN that think we could engage in Littoral combat, but they are in the extreme minority.
No naval officer ever wants to bring his ship so close to shore that one of those missiles could hit it. And if you are out of range of ground fire the only way to fire is ship based, that exposes the firing ship to submarines which are damn near impossible to detect. The other option is submarine launch, which again on launch exposes the asset and anti-submarine warfare is very well understood at this point. And why launch an anti-ship missile from a submarine when a torpedo can be far more damaging.
The navy is working on a platform for the rail guns that uses current working technology. The systems they are developing will run on top of standard carrier nuclear generation systems. Just like the carriers you have two small nuclear reactors, put them in a large cruiser class ship. There aren't big guns like the old battleships so the ships become multi-role, able to host not only rail gun rounds but missile and radar emplacements. The best part about the rail guns is you do away with explosive munitions, your ammo and firing system are a bunch of wiring, capacitors and a hunk of tungsten for a projectile and you can spread the systems around the ship in a damage control technique (unlike current powder based systems that are a single weak point).
I actually believe the Navy's future plans are more sustainable and build-able than even the air-force's F-35 program. And their time line is even more believable with the first ship construction around 2016.
Re:Is this news? by rahvin112 · 2012-10-01 12:51 · Score: 5, Interesting

I shouldn't need to point this out as it's a critical aspect of US naval policy since WWII. The point of a US navy carrier grouping is to sit well outside ground fire range and use AIR power. This means planes with ranges that far exceed a missile, and cruise missiles that are nothing more than preprogrammed Kamikaze drones.
Maybe at some point the SunFire's and other supersonic Anti-Ship missiles will have a range equivalent to air power but the further they have to go the easier they are to shoot down.
The first rail guns will be small systems with short ranges of 200 some odd miles, but the future intent is to bring these up to 2 Ton 10,000 mile systems. They will have the ability to throw a hunk of tungsten so fast and so far that it's explosive force will be in the 30K ton of TNT range and it will be capable of penetrating almost a hundred feet of solid rock or reinforced concrete. They will be capable of putting a rod on target within 5 minutes of order. Railguns will revolutionize warfare, probably in a very bad way.

Old news... by Valor958 · 2012-10-01 08:22 · Score: 5, Informative

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...

Re:Old news... by EvolutionInAction · 2012-10-01 08:41 · Score: 5, Informative

Unfortunately you're dead wrong. We can power them. Maybe not easily, but we can do it. The problem is that you get something like three shots before the rails have eroded to the point of uselessness. Too much friction, too much electrical arcing.
Re:Old news... by Nadaka · 2012-10-01 09:03 · Score: 4, Interesting

Next gen aircraft carries are already putting in an extra reactor in order to run electromagnetic launch catapults instead of the high maintenance hydraulic ones we have now.
When that power isn't being used for launching aircraft, it can be used for launching railgun projectiles.
Re:Old news... by FileNotFound · 2012-10-01 09:13 · Score: 4, Insightful

Yeah - but can you replace the rails while underway?
Here's something for you - a DDG carries 56 Tomahawks, but can load up to 96 if they carry nothing but Tomahawks in their VLS. Rate of fire - 1 missile per second.
The real question is, what are you going to shoot at that's only 200mi aways? 200mi might sound "far" but reality is that modern anti ship missiles have range 500-1000 miles.
No DDG is going to sail up to 200mi of a hostile to shoot it with a railgun when then can launch a Tomahawk with it's 800mi range for a Block III or 1500 for Block IIs.

--
In Soviet Russia, the television watches YOU!
Re:Old news... by Phanatic1a · 2012-10-01 09:56 · Score: 5, Interesting

"They won't be willing to wait and it's not exactly a simple thing to change the power output of a Rankine cycle nuclear power plant at a whim."
Actually, it is, it's called a throttle. When you're in a nuclear submarine puttering along at 5 knots and someone drops a torpedo on you, and you want to get up to 30+ knots as fast as you can, you do it. You take more heat out of the coolant, which cools down the water in the reactor, which increases the reaction rate, which produces more power, this relationship is very tight and the changes can happen very rapidly. Way more rapidly than shoveling in more coal.
The power source is a non-issue. Gas turbine, nuclear, whatever, there's plenty of available power. A single destroyer carries 4 gas turbine engines that are each capable of 40,000+ shaft horsepower. It's generation capacity that's more of an issue, but even that just means "wait for a longer period of time between shots."
The means of delivering electrical power to the projectile without arcing destroying the rails is an issue. Ideally you want all the current in the world at as low a voltage as you can manage it, so capacitors aren't as good as a magnetohomopolar generator. But getting the power to put into the capacitors of MHG is not a complex problem.
Re:Old news... by Baloroth · 2012-10-01 10:03 · Score: 4, Interesting

No DDG is going to sail up to 200mi of a hostile to shoot it with a railgun when then can launch a Tomahawk with it's 800mi range for a Block III or 1500 for Block IIs.
...at ~$600,000 dollars a shot. That is... expensive, even for the US military, especially when fighting targets that aren't ~1,000 miles away, but which you still don't want to fly a plane over. Also, carrying 56 Tomahawks means you have a shit-ton of explosives on board just waiting to be detonated by a missile or bomb hitting the ship. The thing about railguns is they can be potentially combined with the new laser system the Navy is also developing for defense, meaning you have a platform that can't be hit by enemy missiles and can fire large-scale bombardments for nearly negligible cost (compared to the current cost), over the horizon. Sure, that's a few years or even decades down the line, but when your military operates on the principle of always having the technological upper hand (which is exactly how the US military works), investing in tech that is 10+ years away is a rather sound move. Not to mention the other applications rail technology could have, like space travel.

--
"None can love freedom heartily, but good men; the rest love not freedom, but license." --John Milton

Technology improving warfare! by jellomizer · 2012-10-01 08:31 · Score: 4, Funny

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.

Re:Technology improving warfare! by evil_aaronm · 2012-10-01 08:41 · Score: 4, Insightful

You can take people out of the stone age, but you can't take the stone age out of the people.

You missed one. by Anonymous Coward · 2012-10-01 08:44 · Score: 4, Insightful

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.

Re:You missed one. by Martin+Blank · 2012-10-01 10:32 · Score: 4, Interesting

I don't think so. I don't know for sure that the $190M F-22 is six times better than a $30M F-15, but it's a lot more than 19 times better than the MiGs it's likely to face. Oh, maybe not the MiG-29, where it's perhaps only eight or ten times better, but the F-22 has the ability to knock you down from 60 miles out (around 100 miles when the AMRAAM-D comes along). Even one F-22 and a few F-15s would make short work of 20+ MiGs at $10M each since at that price, you're using comparatively ancient MiG-23s and not even MiG-29s, which cost three times as much.
Besides, the factor you missed is AWACS. That's a force multiplier of unbelievable proportion. Iraq learned that the hard way twice. When you have someone watching your back for missiles and aircraft from that far away who isn't likely going to get distracted because someone took a shot at him, it's a powerful ally. Knowing which group of enemy aircraft to target, where SAM sites are, how long an enemy aircraft has been flying (and thus how much fuel they might have left), and other tactical information helps enormously, and anyone fielding F-22s is going to have one or two AWACS planes up there guiding things.

--
You can never go home again... but I guess you can shop there.

Explosives by ShakaUVM · 2012-10-01 08:47 · Score: 4, Funny

""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.

Re:How high can it shoot? by Deadstick · 2012-10-01 09:34 · Score: 4, Informative

You can't put anything in orbit with any gun, acting by itself. You must apply some thrust after the projectile reaches the desired height. If you don't do that, no matter how powerful the gun is, no matter how high the muzzle velocity is, no matter where you point it, one of two things will happen: it will hit the earth before completing one orbit, or it will fly away and never come back.

If you want to launch to orbit from a gun, you have to provide a rocket motor on the projectile that starts up at the appropriate point in the trajectory.

Here's another way to express it: you cannot achieve a repeating orbit whose low point (perigee) is higher than the last point at which thrust was applied. For a simple gun, that point is the muzzle.

Re:Fear it Iran by X0563511 · 2012-10-01 09:42 · Score: 4, Funny

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...

Re:really ? by downhole · 2012-10-01 12:14 · Score: 4, Insightful

Not sure if GP was serious or not, but looks to me like the modern US Army and other armed forces go to an unbelievable and completely unprecedented amount of effort to avoid collateral damage compared to every other military force that has ever existed. Those who seriously complain about it either have no idea what they're talking about, or are pursuing an anti-American agenda and don't have the courage to be straightforward about it.

--
I don't reply to ACs

Re:How high can it shoot? by rubycodez · 2012-10-01 12:19 · Score: 4, Interesting

wrong. there are trajectories in a multi-bodied system such as the earth-moon one where orbit can be achieved. your teacher or urban-legend websource was only considering the earth as a lone body.

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The US Navy's Railgun Program

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