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Wednesday, February 06, 2008

Electromagnetic Railgun Blasts Off

Continued from page 1

By Brendan Borrell
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Jon Kitzmiller, an expert in electromechanical systems at the University of Texas, who worked on an earlier railgun project, says that the navy team is "going to have considerable difficulty getting [to 64 megajoules], but it's certainly achievable." He says that the navy's budget of $40 million a year secured through 2011 proves that it is serious about making the gun a reality in the next 15 to 20 years. The previous effort was derailed by funding constraints.

One of the biggest challenges, says Kitzmiller, will be in designing a power supply that can handle multiple shots. "In order to store multiple 64-megajoule shots on a capacitor bank, you would need an aircraft carrier full of capacitor banks," he says. One solution, Kitzmiller and Garnett agree, is a system of rotating pulsed alternators, called compulsators, rather than traditional capacitors.

Other challenges include developing a projectile guidance system that can withstand 40,000 gs--twice the acceleration of current systems--and building a gun barrel that can withstand the force and heat produced by repeated firings. The same force that drives the bullet out of the barrel also tears the rails apart. The Dahlgren prototype looks nothing like a typical gun, and parts will frequently have to be replaced.

"Firing a gun once or twice [makes it] a novelty," says Garnett. "Firing it a thousand times [makes it] a weapon."
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Comments

  • Idiots.
    DJTal on 02/06/2008 at 3:45 AM
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    I think you'll find a lot of people are sick and tired of these war mongering idiots ..... Admiral Roughead !?...please . Surely the past 5 years of war has shown just how little can be achieved with military force in the modern age .
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    • Re: Idiots.
      Siphis on 02/06/2008 at 6:39 AM
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      Idiots indeed!  Why, war has never resolved a thing has it?  A complete waste of time, blood, and treasure.  Except for a few trifling exceptions such as ending the Nazi terror in Europe and Japan's conquest of the Pacific, and the U.S.'s independence from Great Britain, and ending slavery in the U.S..  There are, regretably, a few other nasty bits that didn't turn out quite so pleasantly for the participants like the Russian revolution (tough time for the menshiviks), Cuba, Cambodia, Korea, etc. 

      Damned if there isn't always some fellow out there who isn't quite ready to be reasonable, open to discussion, and willing to forgo amicable relations with the greater Global Village in favor of simply taking everything by force.

      And you're also spot on about the obsolesence of military power in this modern age of Dignity, Respect, Equality, and Warm-Fuzzy Feelings.  A 12 year dialogue with Saddam got him to peacefully abide by the the UN's High Commission for Happy Thoughts.  And that cheery little fellow over in North Korea, isn't that just a sterling example of how peaceful, non-confrontational, and perfectly innocent little chats can get anyone to abandon megalomania, hatred, and naughty thoughts.

      Oh, I haven't looked in on things lately, but I presume that all of the positive energy we've been sending over to Darfur has put an end to all that genocide nonsense.  Right? 

      Cheers,
      Siphis
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      • Re: Idiots.
        stradric on 02/06/2008 at 9:10 AM
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        I'm usually among the first to argue that certain new weapons of war are little more than boons to the military industrial complex, but this one in particular makes a lot of sense.

        Lets get one thing straight.  War is not going anywhere (and certainly not while it's still so profitable to the military industrial complex).  I would agree that the mil. ind. complex wants war when stripped down to the bare bottom-line corporate mentality.  But if you take that away, there is still going to be conflict.  So, things like this that can potentially save American lives are fantastic in my opinion.

        It's the politicians that abuse our military to enrich the few that gets to me.
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      • Re: Idiots.
        SirLanse on 02/06/2008 at 9:11 AM
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        You forgot to mention how the happy thoughts
        changed the way Islamo-faschist viewed us during the Clinton years.
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      • Re: Idiots.
        timbo on 02/06/2008 at 9:13 AM
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        The anti-military technology line is typical for those who belive that all we need to do is hold hands and sing kumbi-ya (or something like that).  We have lot of bad guys out there and having the technology to take them out quickly is a great relief and benefit.  Compare "collateral' damages and losses in recent conflicts vs. say WWII - technology has allowed us to beat the enemy and minimize casualties.    
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      • Re: Idiots.
        opus61856 on 02/06/2008 at 9:34 AM
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        Who needs weapons? I'm sure that a group hug will solve everything.

        All of the world's lunatic dictators are just misunderstood.

        I'm sure that if the United States stops developing future weapons everyone else will as well.
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        • Re: Idiots.
          aquiles on 02/06/2008 at 1:03 PM
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          A tiny portion of the current might of the US military should be enough to topple any of the five or so remaining dictators in the world.

          This kind of research and development of new weapon systems is simply stupid given the fact that national wars have become a thing of the past.

          It's urban guerrillas and the terrorist that these foster that should be the focus of US military research these days. But you can't combat a terrorist cell housed in the middle of a poor neighborhood in the third world with big guns such as these.
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          • Re: Idiots.
            n8allan on 02/07/2008 at 10:01 AM
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            Unfortunately it is naive to believe that future threats to the U.S. will be limited to small factions.  Though they are usually excluded from popular discussion, both Russia and China are demonstrably and diligently working towards arming themselves against the U.S.  Let's not forget where weapons like Russia's latest set of ICBMs are pointed: The U.S.!
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          • Re: Idiots.
            utimmer43 on 02/10/2008 at 1:39 AM
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            "A tiny portion of the current might of the US military should be enough to topple any of the five or so remaining dictators in the world."-aquiles

            Using "just enough" force to win will guarentee defeat (take this current war, for instance).  If you're going to fight, you fight to win, and you do so with overwhelming force, and get it over with. 

            "This kind of research and development of new weapon systems is simply stupid given the fact that national wars have become a thing of the past."-aquiles

            Keep on preaching that.  As soon as everyone believes it, see what someone like China tries to pull.  (and don't try telling me that China is our friend)
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      • Re: Idiots.
        DJTal on 02/07/2008 at 4:07 AM
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        Thankyou for confirminig the stupidity of the military solution . The fact that we had to fight wars in the PAST demonstrates just how little effort was made to prevent war via peaceful solutions . Was WW2 necessary ? At a certain point yes , but it could have been prevented earlier . Did we have to fight a war in Iraq ? Not if the weapons inspectors had been allowed to do their job . China has demonstrated how North Korea can be pacified with economic aid . Hopefuly future problems can be resolved peacefully or would you rather have more military activity ?
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        • Re: Idiots.
          Kodiak on 02/09/2008 at 3:49 AM
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          "China has demonstrated how North Korea can be pacified with economic aid."

          So you're suggesting that we should buy off (read: bribe) tinpot dictators whenever they act out? That's a mighty short-sighted solution. It means international security can be held hostage by any world "leader" who gets strapped for cash... even if his (or her - I'll be an equal opportunity sexist) cash flow difficulties come from reckless spending (probably to support a lavish personal lifestyle). "All I have to do is rattle my saber and other governments will fall over themselves to give me money."

          Also, you conveniently neglected to mention why those weapons inspectors weren't allowed to "do their job." I wouldn't have been because [gasp] Saddam objected, would it? Gee, your "solution" puts all the control into the hands of selfish tyrants who don't care about anyone but themselves.

          "You didn't think this through too good, did you?"
          - Christopher Walken as Carlo Bartolucci in Suicide Kings
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          • Re: Idiots.
            DJTal on 02/09/2008 at 10:46 AM
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            The boneheaded simplicity of your arguement and others is the problem........you see the options as either blowing the hell out of your enemies or giving them a big hug . It's not black and white . Perhaps you haven't heard the criticisms made by Hans Blix the chief weapons inspector .
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    • Re: Idiots.
      tom500k on 02/06/2008 at 2:23 PM
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      Is it scientifically (not to say intellectually or ethically) defensible for the academic center of higher learning, MIT, to pretend that the solution for our ills is purely technological, particularly technology for killing folks?

      When will MIT Technology Review examine in print its tacit premise that the solution to all problems is entirely new technology, particularly technology which will attract DOD funding and add to the stock valuation of our patriotic weapons makers?

      The work of Professor Richard A. Pape, ironically funded in part by DOD, provides empirical support for the notion of withdrawing from countries that we in the US currently occupy is a far more effective solution if our real goal is security, rather world domination. I don't expect that his work will grace the pages of Technology Review since it hardly provides support for even more exotic wonder weapons.

      Would it not be intellectually honest for the MIT Technology Review to publish on the limits of purely technological solutions before the US and other nations and groups committed to novel violent low or high tech "solutions" which even in the short run will likely kill us all?

      Yes, such an article risks offending DOD and endanger MIT's position as the #1 academic grantee of DOD largess , but then that risk might be rational if it increases the probability of a full (rather than truncated) life for everyone's children and grandchildren.

      Reason demands that we examine the limits of the hugely profitably cow of technology, especially technology designed to kill ever more effectively. I believe that particular path to peace was discredited by Alfred Noble, who tried to repent of his folly by endowing a peace prize. Will we as a nation, ever repent of our folly and reverse direction?

      may the gods forgive us all for our participation in the unexamined, counterproductive hubris [which scholars from Viktor Frankel (hyperintenionality) , Touchman (the pursuit of folly) to Chalmers Johnson (blowback) warn us leads to our own annihilation by invoking the fury of the goddess, Nemeses],

      Tom, who once was a true believer in the omnipotence of technology to solve all problems -- my own idiotic hubris and wasted years...

      P.s. My earlier comment (2002) disputed the article of faith that Iraq was sitting on a mountain of WMD's. This skepticism earned me the wrath of TR readers. I wonder if those who attacked my skepticism about the alleged Iraqi WMDs so vehemently are in Iraq still searching for WMDs other than DOD's policy of violation of Article 4 of the Geneva Convention which mandates that the occupying power (us) is compelled to preserve the lives of the occupied rather than annihilating civilians via the Peaches Patrais' El Salvador option as well as cutting the slow starvation food ration of Iraqi civilians in half starting January, 2008?

      Qu: how is US government propaganda superior to that of the classical dictatorships who also sought world domination.

      Ans. Greater sophistication... I'm confident that "Peace through strength" and "Stay the Course" score higher with focus groups than "Arbeiten macht frei"*.

      * Perhaps someone will correct my German which I failed ignominiously as an undergraduate.

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      • Re: Idiots.
        oconnmic on 02/07/2008 at 9:10 PM
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        Ummm...did you notice this is the "Technology" Review?  I think you're looking for the "Luddites" Review.
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    • Positive Benefits
      RD on 02/06/2008 at 3:05 PM
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      Rail gun technology can be used for asteroid and low gravity planetary mining, and propulsion.  As a weapon it doesn't leave chemical vapors, or need depleted uranium.  It can be used as a ground penetrating bunker buster.  The projectile can be very small thus reducing collateral damage.
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    • Re: Idiots.
      irreverent on 02/09/2008 at 12:34 AM
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      The U.S. military budget is an obscenity. No one else comes close to spending as much. No telling how many countries we may have to impose our form of government on. There is always some other boogie man out there that the U.S. military is running straight to the bank for. And look how effective military might is at bringing political solutions to the middle east. But I do find rail guns fascinating, particularly the potential for reaching escape velocity, that might come in handy some day. We could load up the moon with nuclear waste, generals and politicians.
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  • back to engineering
    SVE on 02/06/2008 at 10:10 AM
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    On a technical note- what are the scaling laws?

    I wonder how the technology scales with size. I see how the forces are enormous when handling 20 and 40 pound projectiles. Are the design problems of power supplies & material strengths easier when applied to smaller weapons like a hand-held gun or a pea-shooter? Would those be more practical?
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  • Space Launch
    scottaye on 02/06/2008 at 10:37 AM
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    If pointed upwards how high would the shell go?

    Wonder if you could use multiple firings to boost material into orbit and then assemble into useful structures?

    Could you fire water filled shells to the ISS? Would it be cost effective?

    Looks like fun to test, must make a very satisfying bang.
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    • Re: Space Launch
      alexarion on 02/06/2008 at 10:59 AM
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      With 60MJ for instance, we can only send 60kg at 100km - and that if we ignore loss of energy due to friction.
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      • Re: Space Launch
        tom500k on 02/06/2008 at 2:38 PM
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        Do other folks concur with DJTAL in rejecting the "logic" of limiting discussion of the railgun to technical considerations alone.

        The words of Tom Lehrer (MIT, long ago) come to mind:

        "The widows and orphans of old London Town owe it all to Werner Von Braun. Where zehay (the V-1s and V-2s) come down is someone else's department."

        Did the Nazis lose WWII or just move to Boston?






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      • Re: Space Launch
        johnnizanni on 02/16/2008 at 12:22 PM
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        100 km is enough to get it started!  It would significantly cut down on the fuel load needed if a rocket engine then took over.
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  • Just not cover any technology with military uses?
    cobraphx on 02/06/2008 at 4:09 PM
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    Is that what is being suggested here? That MIT not publish articles about technology that has military applications? Should they not have published articles about carbon composites because they were a major portion of the B2? Seems that has trickled down to the new Boeing 777. What about advanced remote-presence operating suites, the MIC is looking to field that technology, which could also help people in third world countries. DARPA is spending money to build better artificial limb... is that off limits because the military is doing the funding?

    Funny thing our MIC, a lot of the technology we rely on daily is here because the military pushed money into funding it's development. The internet, GPS, cordless phone spread spectrum technology, cell phones, advanced composites, jet airplanes... they would have gotten here eventually, but the MIC pushed the development of plenty of things we take for granted.

    Doesn't mean I'm a war monger. But at the same time I don't believe research should be stifled because it has a military application. Who decides which technologies have "too much military use" and should be ignored/banned/stifled/shunned/rejected? 
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    • Re: Just not cover any technology with military uses?
      hachi on 02/06/2008 at 4:41 PM
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      Hear, hear.
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    • Re: A commonly used fallacy: military R&D helps civilian life
      gabrielg01 on 02/06/2008 at 5:49 PM
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      Dear cobraphx, it seems like you got owned by a very commonly used fallacy. Namely, that we should accept the high price of military R&D programs, because the fruits of these will eventually trickle down to the civilian sphere. This is practically a smoke-and-mirrors trick, to distract people's attention.

      The right question to ask would be: Why couldn't we support civilian R&D directly? Why is the military route necessary at all? Couldn't we develop GPS, carbon fibers etc. etc. directly for civilian purposes? Then the military could adopt them too, if they wished to do so.

      The secrecy involved in the military R&D makes everything 10 times more expensive. Developing technology via the military route also means that the civilian sphere will have to wait for decades before it gets to use it.

      Military R&D is a bad deal for the tax payer. We could get a lot more bang for the buck if we supported civilian R&D.
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      • A commonly used fallacy: military R&D helps civilian life
        cobraphx on 02/06/2008 at 6:35 PM
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        Do you think GPS would be open to everyone to use if it were developed by a corporation instead of the military/government? So you give money to Ford, or Gm maybe Microsoft to develop GPS, they launch the satellites, and then they charge an exorbitant amount of money to allow other companies devices to use their signals, or they make it a proprietary system to keep other vendors from using the fruits of their research.

        I didn't say the the military development of technology was the most cost effective means to develop consumer technology. I agree that's it's not a good system, there is plenty of corruption, and Good Old boy networking going on. What I did say was that lots of things developed for military applications are later adopted for civilian applications. If you ignore every technology that has military application, plenty of everyday uses for that same technology will not come about.

        The military can spend money on technology development that doesn't have immediate benefits. The same is not true for the average American corporation that is driven by the fickle short-sighted American Investor. Investors will not stand for a company to risking huge sums of money on R&D to develop something that doesn't have immediate market and sales potential.

        Do we need railguns? I don't know, but if the railgun project develops ultra capacitors or some other energy storage mechanism that can speed the adoption of electric vehicles, I think it's well worth doing the research.

        Like it or not, until governments and religions around the world can agree to get along (fat chance of that happening any time soon), we have to have maintain an advanced and effective military.
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        • Re: A commonly used fallacy: military R&D helps civilian life
          GaryB on 02/06/2008 at 9:09 PM
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          You're all forgetting one thing:

          Making chunks of metal go really really fast is ... just ... really really cool.

          Now that we established that, I'd like to argue that there is in fact a technical solution to every problem, at least those that we care about. I think for this silly terror war, the solution is almost certain to lie more in just guarenteeing a market for solar energy generation coupled with some even cooler robots.  But still, I want a rail gun that will chuck bulky inert things into orbit, and its high time we figured out how.
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        • GPS.
          DJTal on 02/07/2008 at 4:12 AM
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          Where does the military think it gets it's money from ? GPS doesn't belong to the military .
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          • Re: GPS.
            sishquebob on 02/07/2008 at 9:26 PM
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            They invented it and no they do not own it. We all do it is our taxes that fund the replacement of GPS satalites. I'm sorry but I get sick and tired of people huffing and puffing about the source of our research and our technology. I know it has been said allready but almost ALL of our technology that we take forgranted was born out of military needs. It is a vicious process but unfortunately one that is needed. Also as a bit of food for thought, what if we did not have the technology that we do today? How many thousands or millions of our men and women would have died over the last half century? So I think this technology is a god send in the potential to save lives. Also remember THEY HIT US FIRST! It seems to me that almost everyone forgot about the events of Sept. 11th 2001.
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            • Re: GPS.
              mistywindow on 02/09/2008 at 12:46 PM
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              Who hit you first?
              A bunch of lunatics led by a citizen of the US's bosom buddies in Saudi Arabia who's still on a camping holiday.
              The other lunatic, Saddam, and the Iraqi people had nothing to do with it.
              People keep forgetting that.
              Nevertheless, this is viable research and if we can't stop killing one another I suppose it's a relatively good thing that we find less messy ways of doing it.
              Sad though, isn't it?
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              • Re: GPS.
                freelane on 10/20/2008 at 8:19 PM
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                You need to stop getting your news only from the mainstream media which is so anti-Bush that they can't see part their own hatred; ie CBS, NBCBS, ABCBS, CNNBS, BSNBC, etc.  It has been proven that Al Qeda had training camps in Iraq, that the leader of the 9/11 terrrorists was in Bagdad about 2 weeks before the attack meeting with gov't officials about strategy, intelligence and probably funding, that Saddam was funding many terrorists (we don't really know if these were some of them, but it's not a far stretch), that he killed hundreds of thousands of hiw own citizens and many Iranians with weapons of mass destruction, that there were many weapons in Iraq just before the war and during the entire time the UN was impotently trying to get him to give them up, that many, many components and raw materials for WMDs have been discovered in Iraq along with massive documentation on how to assemble the weapons, equipment to assemble it, etc.  The only people who don't believe attacks from Saddam were immenent are immature, juvenile, fantasizers, not serious adults, who must protect our entire civilization. 

                Our governments big mistake was in not having a better exit strategy and probably in not dealing such a massive blow to Iraq that other terrorist supporters would think twice before screwing with us.  Grow up!
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