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The Military Technology

Navy Tests Mach 8 Electromagnetic Railgun 440

hargrand writes "Wired magazine has a story and publicly released video of the Navy test firing of a 32 megajoule electromagnetic railgun: 'Reporters were invited to watch the test at the Dalghren Naval Surface Warfare Center. A tangle of two-inch thick coaxial cables hooked up to stacks of refrigerator-sized capacitors took five minutes to power juice into a gun the size of a schoolbus built in a warehouse. With a 1.5-million-ampere spark of light and a boom audible in a room 50 feet away, the bullet left the gun at a speed of Mach 8.'"
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Navy Tests Mach 8 Electromagnetic Railgun

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  • by marcovanb ( 1957070 ) on Saturday December 11, 2010 @05:20AM (#34522170)
    I've heard that before "Rule Britannia, Brittania rules the waves...".
    • Comment removed (Score:5, Insightful)

      by account_deleted ( 4530225 ) on Saturday December 11, 2010 @05:45AM (#34522240)
      Comment removed based on user account deletion
      • Re: (Score:2, Insightful)

        by Splab ( 574204 )

        As long as the development of said supergun is in the US, you are doing it right.

        Problem starts when mass production starts ordering equipment overseas - development and production of military equipment = jobs which help the economy, where ever it takes place, trick is to make sure you build it in your own garden.

        • by rolfwind ( 528248 ) on Saturday December 11, 2010 @06:12AM (#34522308)

          As long as the development of said supergun is in the US, you are doing it right.

          Problem starts when mass production starts ordering equipment overseas - development and production of military equipment = jobs which help the economy, where ever it takes place, trick is to make sure you build it in your own garden.

          Really, is that the depth of your economic thinking, whoever has the biggest guns rules? I'm pretty sure the Soviet Union never outsourced the production of its weapons either.

        • by Xaositecte ( 897197 ) on Saturday December 11, 2010 @06:14AM (#34522316) Journal

          Y'know, if we hired a little kid to start throwing rocks through windows all over the city, so many that we'd have to open another glass production plant to meet up with the demand for new windows, we'd also help the economy. Especially if we built it here in America.

        • This kind of spending is nothing more that a giant stimulus package, but without any hope of secondary beneficial effects. You could simply take all that money and give it to the workers directly. That would be much cheaper,because you don't need to pay fo the materials (not to mention the revenue of the company owners).

          • by Dunbal ( 464142 ) *

            If you start handing out money you destroy its perceived value. The current understanding is that money is "hard to obtain" and requires effort.

          • Normally, the point of this is to keep defense contractors in business when there isn't a war on, or to develop future technology. The problem isn't that we're doing it, the problem is that we're borrowing massive amounts of money to do it, even as we spend massive amounts of money on superfluous wars.
        • by DarkOx ( 621550 )

          No, doing that stuff is a short term stimulus at most long term its a hidden tax on all of us. Using fiat debt money to build a super gun is much different than say building a road. If you build the road the economy continues to extract value from its use.

          The gun on the other hand gets taken off to war and sooner or later destroyed but all the money that went into it is still here at home doing its evil inflationary work. The same thing is basically true in a sound money system but there you'd have defla

          • Comment removed based on user account deletion
            • Though this gun probably isn't an example, many fancy new weapons do go on to make money for the US through sales to allies (and even not-so-allies).American fighter jets and rifles have been bought up worldwide.

              And those fighter jets and rifles have been used to kill American citizens in wars. Good move... keep that economy going. Good move, that is, if you are a 'fortunate son'.

      • by Charliemopps ( 1157495 ) on Saturday December 11, 2010 @06:09AM (#34522296)
        if you're done ranting now... railguns have plenty of non-military uses. The research into how to charge and quickly discharge those huge capacitors alone is very useful. Not to mention the applications for launching stuff into orbit, or in fusion reactors. As weapons they are great for taking down incoming missles. Also, if they were to make portable versions it would eliminate the need to carry dangerous explosives (gun powder, C4, etc..) and the projectile itself wouldn't be a dangerous heavy metal like lead. I'd rather see the military spend their time doing research like this than invading another 3rd world country.
        • by dbIII ( 701233 )

          and the projectile itself wouldn't be a dangerous heavy metal like lead

          I thought you had a solid grounding in reality until I read this. You don't want to ingest lead but really in this application how much of a risk is that going to be? The stuff inside the capacitors is most likely a hell of lot more toxic than lead! There are a lot of heavy metals a lot more dangerous than lead.

          • by JDevers ( 83155 )

            I would say that the real flaw there is that we don't exactly use lead projectiles in ship to ship warfare either.

      • by TubeSteak ( 669689 ) on Saturday December 11, 2010 @06:15AM (#34522322) Journal

        We already have the largest aircraft carrier fleet on the entire planet, our most likely enemies are groups like NK and Iran that would be lucky to come at us with kamikaze speedboats, and THIS is what we add even more debt for?

        BTW - When we did red vs blue naval wargames a few years back, those kamikaze speedboats kicked the blue team's ass.

        It was so embarassing that... [nytimes.com]

        When the Red Team sank much of the Blue navy despite the Blue navy's firing of guns and missiles, it illustrated a cheap way to beat a very expensive fleet. After the Blue force was sunk, the game was ordered to begin again, with the Blue Team eventually declared the victor.

        The last few meaningful encounters the USA has had with low-tech asymmetric warfare have gone relatively poorly for them.

        • by Anonymous Coward on Saturday December 11, 2010 @09:20AM (#34522922)

          I knew I recognised that story - but it seemed to miss some fairly interesting points for whatever reason...

          http://en.wikipedia.org/wiki/Millennium_Challenge_2002 [wikipedia.org]

          At this point, the exercise was suspended and Blue's ships were "re-floated" and changes were made to the rules of engagement; later this was justified by General Peter Pace as: "You kill me in the first day and I sit there for the next 13 days doing nothing, or you put me back to life and you get 13 more days' worth of experiment out of me. Which is a better way to do it?" In the new restarted exercise the different sides were ordered to follow predetermined plans of action, leading to allegations that the exercise was scripted and "$250 million was wasted". Due to his concerns about the scripted nature of the new exercise, Van Riper resigned his position in the midst of the war game. Van Riper later expressed concern that the wargame's purpose had shifted to reinforce existing doctrine and notions of infallibility within the U.S. military rather than serve as a learning experience.

          The re-floating of blue teams boats was just the start of embarrassing behaviour.

          Quite interesting how US media differs from other parts of the world when telling this story - obviously it might look insulting to you guys, but isn't this the sort of shit you would like to know about? - http://www.guardian.co.uk/world/2002/sep/06/usa.iraq [guardian.co.uk]

      • by Malc ( 1751 )

        The US defence industry is plain and simple a form of welfare, without the "socialist" moniker.

        • The US defence industry is plain and simple a form of welfare

          It's true, but not in the way you sophomorically imply. And the people receiving the benefits of the US having to spend that money and do all of that work are the other countries around the world that opt out of having to do it themselves. There's the real irony: actually socialist-leaning countries in places like Europe get the benefit of cozying up to the US via NATO, while letting the US do the heavy lifting when it comes to paying for this
          • by ctid ( 449118 )

            I don't understand your argument. So when the US spends government money in the defence industries it's not "socialist" (by your definition) to do that in America but it is "socialist" if "socialist-leaning" countries benefit? Are you serious? If so, I'd love to hear your views on the bailout of Wall Street.

          • by Dunbal ( 464142 ) *

            No one is asking you to do the heavy lifting, which is why we resent having it shoved in our faces all the time you stupid American. It's not like you're even doing a good job at it anyway. Then you wonder why everyone hates you. The other day I bumped into an guy with a Canadian flag on his backpack. He left it open on the floor, and my girlfriend asked me if the Canadian passport had an eagle on the cover. You stupid shits are ashamed of your own country when you go abroad, yet you don't stop acting like

            • No one is asking you to do the heavy lifting

              Poppycock. We hear all the time how people resent the US being slow to get into WWII, or how Europeans want US bases to stay:

              http://www.toytowngermany.com/lofi/index.php/t124887-90.html [toytowngermany.com]

              Not to mention everyone and their brother wants in on NATO.

              As far as I am concerned the US should pull up its stakes and come home except where there is a clear national interest as there is in the Middle East. Euros, Asians, etc. you name it can go to hell. No more help against Rus

      • The politicians and military will tell you military developments will filter down to the consumers in some way eventually. So they will continue to justify the amount of spending going on, while the US economy continues to sink into oblivion. Has it not dawned on people in the US government why China has had enough of buying US debt?

        • military spending does trickle down. GPS, Apranet, infrared detectors even the new M-25 all have very valuable civilian or police uses that would be possible without some major money funding their initial 20-30 year developments.

          If you don't know why the M-25 with vaulable for police, it can fire flash bangs, and rubber bullets instead of bombs. You can flash bang a hostage room from far away on one side, while breaching on the other.

      • by tebee ( 1280900 )

        Yep, the US military should have watched more Si-Fi movies - then they'd know that the (evil?) empire with all the cool tech always gets beaten in the end by the brave underdog (freedom fighter/guerrilla - take you pick) fighting with whatever old crap they can beg, borrow or steal.

      • by Hal_Porter ( 817932 ) on Saturday December 11, 2010 @06:31AM (#34522378)

        Sadly I think your joke just hit the nail on the head of one of the things that is seriously fucked up about this country. I mean here we are, factories shuttered all over the place, people losing their homes left and right, over 22,000 factories offshored since 2001, and debt climbing like there is no tomorrow and

        BOOM

        stupid Osprey turkey while we are at it. We already have the most tech heavy military on the planet but as we are seeing in Iraq and Afghanistan all that means exactly jack and squat against the enemies of today. quit blowing money on stupid weapons already, Sheesh.

        I'm sorry, I didn't hear you over the sound of how awesome my 32MJ rail gun is.

      • by KonoWatakushi ( 910213 ) on Saturday December 11, 2010 @06:34AM (#34522386)

        While the defense budget is no doubt way out of control, this is not at all the sort of thing that worries me. It has no practical military value in the near term, and at least produced interesting results.

        I'm more concerned about other high-tech anti-personel weapons or robots, that will inevitably be pointed at people, possible even at our own citizens before long.

        Speaking of waste, and far more disturbing at that, take a look at what the anti-terrorism efforts have spawned [washingtonpost.com]. I really had no idea of the scale of it. Having this turned against our own citizens as the fascism ramps up is truly frightening.

      • until we have to fight China. Its all a matter of time until we get into a giant pissing contest with them over some crap north korea pulls, and get ourselves into good old fashioned war where you get to use things like aircraft cariers and big guns, none of this 'house to house looking for the terrorist' bullroar.
      • Re: (Score:3, Insightful)

        by __aaqvdr516 ( 975138 )

        Overheard somewhere in Europe 9000BC

        "Bejeebus mister Grok. We're out here starvin' and you're trying to fix a piece of string on a flimsy rod so you can what? Shoot projectiles at things?!? We already have a spear and it's worked so well for us. All those animals don't have spears! The best they have are horns! Harharhar Now come help me kill this stupid turkey."

      • >>THIS, this is what we spend our non existent money on? Giant fricking superguns?

        You say that like it's a bad thing. But since the insane awesomeness of a railgun doesn't impress you, let's look at the numbers.

        >>(we already have 11 carriers for the love of Pete)

        Okay, so you like our carrier fleet?

        Railguns are being designed to counter a threat to carriers, namely swarms of cruise missiles. The amount of money they've spent on developing this thing ($211M) is less than one percent of what Califo

      • While I imagine that a super railgun isn't the best thing to spend money on, I can think of much worse things. Some of the things that would be worse are the things that we have already been spending our non-existant money on like stimulus packages, company bailouts, and more entitlement spending. These things are certain to crash our economy and we're seeing the effects.

        Right now, I'm not a big fan of spending anything that we don't have to. With those other things, the only thing that we get from the spen

      • by dbIII ( 701233 )
        That money is a drop in the bucket compared with the bad debt from lending to developing nations that we like to keep in debt so we always have influence over them. The only reason the dollar isn't behaving like currency in Zimbabwe is because it is the default international currency. Maybe that's enough to keep it up forever, but maybe not. The policy for a long time is have huge debts and loan out money that will never come back and hope the US dollar is too big to fail. While that is going on HUGE mi
  • by PolygamousRanchKid ( 1290638 ) on Saturday December 11, 2010 @05:22AM (#34522180)

    I'm still trying to get them kids off my lawn. But kids on bikes are quick, wily and seem to move in Brownian Motion tracks. Mach 8 could give me a good tactical advantage . . .

  • So if they pointed this sucker 'up' would it be able to throw stuff (you don't mind being squashed - a bit!) into orbit?
    • Re:Mach 8 to Orbit? (Score:5, Informative)

      by Rakshasa Taisab ( 244699 ) on Saturday December 11, 2010 @05:34AM (#34522212) Homepage

      Mach 8 = 2 722.32 m/s.

      Escape velocity being 11.2 km/s, so the answer is no.

      • by DirePickle ( 796986 ) on Saturday December 11, 2010 @05:41AM (#34522232)
        You win again, gravity!
      • Re:Mach 8 to Orbit? (Score:5, Informative)

        by Interoperable ( 1651953 ) on Saturday December 11, 2010 @05:46AM (#34522246)
        Escape velocity is the velocity required to leave orbit, not to maintain a stable orbit. Of course, low Earth orbit is about 8 km/s, so still no.
        • Re: (Score:3, Informative)

          by Rockoon ( 1252108 )
          At a deceleration of a constant 10m/s^2, it would still take 270 seconds to stop going up (the deceleration would actually decrease the higher it goes, but I'm not accounting for drag.. so its a tradeoff) it will have an average speed of 1.35km/s.

          Thats 270s * 1.35km/s = a height of 364.5km, so it could conceivably enter into the region we call 'low earth orbit' which is between 160km to 2000km.

          I dont know where to begin to calculate the drag as it rises, so I wont bother to calculate the decreasing dece
    • Re:Mach 8 to Orbit? (Score:5, Informative)

      by sulimma ( 796805 ) on Saturday December 11, 2010 @05:56AM (#34522258)

      If something is thrown or shot, the orbit will go through the point the shot was fired. You have a problem if that is on earth surface. Even if you are fast enough for a stable orbit you need a rocket to shift that orbit away from your starting point.

      • If something is thrown or shot, the orbit will go through the point the shot was fired. You have a problem if that is on earth surface. Even if you are fast enough for a stable orbit you need a rocket to shift that orbit away from your starting point.

        Shoot twice, then move gun quickly.

      • But that means you need a rocket that is orders of magnitude smaller.

  • by blind biker ( 1066130 ) on Saturday December 11, 2010 @05:49AM (#34522252) Journal

    ...I would be also interested to see what the projectile does at the "destination". Time to buy me some kilofarad supercaps :)

  • This might have been the ideal plot for a "survival" game for the 8-bit platforms. The mighty cannon takes 5 minutes to charge...the counter starting from 300 and dropping down...hordes of enemies crowding the cannon, some turrets or else controlled by the player which shoot down the enemies...I can even hear the frenzy music created by the oscillators of the C64 SID...Great plot, indeed.
  • 50 feet away? (Score:5, Insightful)

    by Sowelu ( 713889 ) on Saturday December 11, 2010 @05:58AM (#34522266)
    Summary says the boom was audible in a room 50 feet away? If I tip over a chair, it's audible in a room 50 feet away...
  • Hmmmm... The Washington Post article said Mach 5. In fact, it seemed more informative in general. http://www.washingtonpost.com/wp-dyn/content/article/2010/12/10/AR2010121007437.html [washingtonpost.com]
  • a boom audible in a room 50 feet away

    that is, ... almost as loud as dropping a frying pan. Very impressive.

  • by Hamsterdan ( 815291 ) on Saturday December 11, 2010 @07:31AM (#34522506)

    Only one Quake2 reference, and none to Bayformers :(

  • by Doc Ruby ( 173196 ) on Saturday December 11, 2010 @11:38AM (#34523706) Homepage Journal

    Charging 33Mj in 300s is only 110KW. A US house typically takes from the grid 200A at 220V: 44KW max (uses a special panel to distribute it; standard is 100A:22KW). So two neighbors and I could charge this thing in just about 4 minutes. It consumes only 9.17KWh, which costs under $1 from the average US grid utility. A US car [greentechhistory.com] floored at about 200KW would charge it in 2m45s.

    Of course the real action is in the firing, when 33Mj is released in (FTA) 10ms. That's 3.3GW, which powers 1.65 million typical US homes (typical SF-sized city + immediate suburbs) at their 1KW average consumption (non-electric heating: if all electric heated, that's about 200,000 Northeast homes in January). At about 35Mj:gal [wikipedia.org] that's only about 9 gallons of gas at 100% efficient electric generation; a typical high-end generator at 20% needs about 45 gallons for each shot.

    Of the storage, quick charging and even quicker discharging this railgun demonstrates I hope the Navy produces even more productive research in just the storage and quick charging efficiencies. Naval ships probably won't want to wait 5 minutes, or even 5 seconds, to reload, so 1.1MW charging is a good target. I don't know whether these capacitors charge in a massively parallel array, but they should; I'm not really sure why all modern batteries don't charge many subcells in parallel for faster charging than discharging - though this gun will never achieve that rate, even if charged on shore by a nuke plant (typically 2-3GW). More research, especially basic science in electrochemistry on nanomaterials, would improve electric appliance performance, especially in our critically growing mobile devices.

    But storage density is the key factor. Destroyers typically carry about 200Kgal of fuel retaining about 25Kgal reserve, plus about 30Kgal jet fuel. A fuel cell at 70% efficiency would need only about 22 gallons per shot; 1000 shots would be less than the reserve. These caps are designed for fast charge/discharge, not capacity, since they're much larger (at least a couple shipping containers, over 5000 cubic feet, instead of 6CF). We need supercapacitors that can store greater than gasoline's 35Mj:l (and better than its 45Mj:Kg). At large scales, capacitors should be much smaller and lighter than gasoline, since each cap atom should store more electrons than in the one or two max in each chemical bond in fuel molecules (and which never completely, or even mostly, "discharge"). This project probably won't do that kind of research, but it could feed other research into that much harder and more common problem of increased storage density.

    In the meantime, it's great the Navy will be able to move to very powerful electric guns. Instead of fuel energy locked up in separate propulsion turbine tanks and ammo charges, the whole mission can be more flexible with electric powering everything. Fuel cells can double or triple (or better) the conversion efficiency, while eliminating emissions (and generating drinking water at sea with no extra energy consumed). Which all means more efficiency, which means less fuel carried around, which means even more efficiency. Ships might eventually carry square KMs sheets of solar panels to float around them, generating a megawatt (in daytime) for charging caps that fire every 5 seconds or faster.

    And the more we get the Navy energy efficient, the less the Pentagon will demand we stay at war to protect global oil supplies, and the more it will prioritize energy innovation that keeps America more independent and effective generally. Which means less shooting, which is the real (and only legitimate) goal of the military: to end wars with America victorious, either by superior force or by avoiding them entirely.

  • by WindBourne ( 631190 ) on Saturday December 11, 2010 @12:22PM (#34523980) Journal
    This kind of R&D will lead to new ultra-caps, but also a much better understanding of how to make things go fast CHEAPLY. For the moment, this is about throwing 25 lbs 200 miles. Once this is done, then we will likely see a new one that will be capable of throwing 1000 or more lbs STRAIGHT UP say 200-300 miles. Once that occurs, it would be possible to send up very cheaply water and nano sats designed to withstand that kind of Gs.
  • by mdsolar ( 1045926 ) on Saturday December 11, 2010 @02:44PM (#34524920) Homepage Journal
    The main advantage of a rail gun is that its muzzle velocity is not limited by the sound speed in a hot gas. Guns that use chemical propellant can't have arbitrarily high muzzle speeds because the propellant gas can't be arbitrarily hot. If you want to go faster, you have to switch from a gun to a rocket and carry the propellant with you. A rail gun gets you back to a gun with rocket speeds and ranges but faster. Since the response can be faster than a rocket, it can provide missile defense by the barrage method and be very effective. It could also be used as intercontinental ballistic artillery eventually. Very powerful and destabilizing....

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