back to article 'Blitzer' railgun already 'tactically relevant', boasts maker

It's all go in the world of hypervelocity railguns this week. Following Friday's 33-megajoule test shot carried out at a US Navy laboratory, it has also been announced that a different railgun known as "Blitzer" has recently carried out firings which suggest that it is almost combat ready. The Blitzer comes to us courtesy of …

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  1. Anton Ivanov
    WTF?

    Smart? At 60000G?

    Lewis, did you by any chance start on the Christmas hampers too early by any chance?

    Can you tell us the unenlightened in the art of ultramodern killware, exactly what kind of guidance package out there will be able to survive that acceleration and actuate fins or command nozzles after that.

    1. John Smith 19 Gold badge
      Boffin

      @Anton Ivanov

      "an you tell us the unenlightened in the art of ultramodern killware, exactly what kind of guidance package out there will be able to survive that acceleration and actuate fins or command nozzles after that."

      A previous US navy project was a naval gun launched "smart shell" using GPS guidance. Can't remember if it's gone to deployment or hit some cost snags but the *hardware* was *very* hard indeed. A far cry from radio proximity fuses in WWII for AA shells using metal shelled valves.

      Generating the power to swivel the guidance fins *is* tough as the forces are quite substantial. Military stuff tends to use thermal batteries. Special, designed to application and *very* expensive but potentially Kw power levels (for enough time to get the job done).

      1. Anton Ivanov

        Errr... Apples and oranges

        You can steer stuff with fins at 1-3M. We know how to do that fairly well.

        Steering stuff effectively with anything _within_ the earth atmosphere at 5M+ is a completely different ball game. This is especially so if the "stuff" is spinning like crazy at several hundred (if not thousands) RPM to maintain its in-flight stability which it will.

        While not outside the realm of the technologically possible, the cost of making the projectile smart in a system like this is likely to negate all the advantages of having a system which can spit out slugs at 5M in the first place.

    2. Brian Morrison
      Thumb Up

      Acceleration figures....

      ...for munitions have been in the tens of thousands of g for decades, definitely 10,000g and maybe as much as 20,000g. Electronics can be made to survive this acceleration because as things get smaller and lighter they are inherently resistant to the resultant forces.

  2. Disco-Legend-Zeke

    In History...

    ...sabot means shoe. Usually wooden

    Early sabotage consisted of kicking one's shoe into the gears.

    </pedantic trivia>

    1. Lukin Brewer

      And in English...

      ,,, the word for wooden shoe was clog. Hence "clogging up the works."

  3. Daniel Evans

    Long Barrel

    Some back of the shopping receipt calculations say that, to reach Mach 5 at 600000ms-2 (roughly 60000 g), you'd need 24 metres of accelerating - a quick wikipedia-ing claims this is longer than the barrels of the guns on Iowa-class battleships (21m). Considering that the US Navy probably don't want ships the size of battleships anyway, and that modern guns generally seem to be quite short, that's starting to sound like a pretty long gun.

    How'd they intend to fit that on a ship?

    1. Chris Seiter

      always about size

      Would a telescopic barrel work? I should probably leave the thinking to the smart ones.

    2. F111F
      Coat

      RTFL*

      In fairness to Lewis, he used the same numbers posted in the GA article..."exceeding 60,000 gee". The picture in the article shows a barrell about 10-12ft (3-4m) long, and shows a shell in flight with fins out, so unless this is a bit of early/late April Fool's on the part of GA...

      *Read The effing Link

      ...mine's the one with the sabot in the pocket.

    3. Martin Lyne
      Heart

      Linear

      No reason the railgun acceleration needs to take place in a linear fashion. Think of the LHC with it's ring shaped acceleration.

      Perhaps having a tight coil is beyond current tech (magnets will be interfering etc), but that's how i always imagined them to work. That or a single loop that then allows the projectile to exit at a given point (fore/aft turret, emergency sea-ditch tube (what would happen if that was fired directly into water? Presumably not fun times). Again think the LHCs emergency dump sections (gets fired into a giant slab of granite)

      Plus.. a gun barrel has to start where the magazine ends (or loading room is situated)

      A railgun could have its acceleration below-decks and just have a fixed-arc turret to actually aim the projectile.

      This is my pseudo-science take on events, anyone feel free to tear it to shreds :D

      1. Loyal Commenter Silver badge
        Stop

        @Linear

        The things being fired around the LHC are essentially points; the slugs in a railgun, as with pretty much any gun are essentially linear. I would have thought it would be extremely non-trivial to make a curved railgun that fires straight slugs.

        1. Mark Boothroyd

          sabot

          only the sabot needs to be curved, the slug can remain straight.

        2. John Smith 19 Gold badge
          Coat

          There's also centripetal acceleration but there *might* be a way round this.

          the particles being fired around the LHC are so small relative to the pipe they're in that from their POV it is a straight pipe.

          The problem is the side force or centripetal acceleration. Using a = r omega^2 with a circle 10Km in radius I got roughly a 16g side force (when the package is hitting orbital velocity of 7950 m^-1) with a 3g front to back acceleration. Not too serious for electronics or anything less complex than say an insect but bad news for humans. Humans don't seem to do 2 axis accelerations well. BTW an F1 driver at 200mph is roughly 89ms^1 or 1/90 of low earth orbit speed. The possible solution follows.

          <unsupported speculation>

          The ring is approximated by an n sided polygon with straight sides and cylindrical chambers at each chamber. The structure is evacuated to reduce the losses of the payload package pushing all that air ahead of itself.

          The wall segments act as linear accelerators giving 3g kicks to the package. As the package free flies between segments (although still under levitation) its yawed about its centre of mass to line up its front end with the next segment for more acceleration. Anything at or near its CM *should* only experience pulses of linear front to back acceleration.

          The structure has 2 exits, one aligned to the latitude and one for a polar orbit. Once the package has reached its release velocity it is diverted to an exit tunnel leading to an exit valve while the rest of the system is sealed to preserve vacuum.

          </unsupported speculation>

          *if* it sidesteps the centripetal acceleration then it just becomes a problem if weather a human can survive repeated acceleration pulses without their sense of balance being permanently scrambled. Using 9144ms^-1/30 000 fps and a 3g acceleration gives roughly 3mins 11 secs

          At least 2 methods exist to handle the attitude problem. Control moment gyroscopes at each end of the package or push/pull electromagnets at the entry and exit of each straight section can do the job if their big enough. Passive magnets have a pull/weight ratio of c50:1 (better than any known jet engine)

          People who've looked at this have talked about "Shutter" valves of metal foils moving on *very* fast carriers. The differential pressure is still only 1 atm.

          Note that while the *rough* layout is simple to describe there are multiple *key* trade-offs which would radically affect how much it would cost to build and run it. The obvious ones are the number of sides in the polygon and the angle of the exit tunnels (45deg gives the shortest length to any given exit height but maximum force needed in the diversion system. Shallower angles give lower forces but much longer tunnels (but with longer to seal the main system). More subtle one would be where to apply the yaw forces. If the package is being turned while still partly *in* a straight section it will need clearance between itself and the wall. Less clearance -> more force -> less power needed.

          This still leaves you with a substantial object moving at orbital velocity at near ground level. The thermal protection system is *not* trivial.

          Mine would have a copy of the last even years February IEEE Trans. Magnetics in. It's the Railgun Issue, packed with all sorts of pulsed power goodness (or alternatively elaborate ways to make yourself the guest of honor at a closed casket funeral).

    4. sT0rNG b4R3 duRiD

      Or...

      put it in a turret that will track fast enough to knock out a variety of threats ranging from (possibly multiple) low flying low visibility missiles/planes to descending MIRV's...

    5. Anonymous Coward
      Boffin

      Factor of 10 out there

      My back of the envelope calculation gives the distance as 2.4 metres.

      distance = (1701.45 m/s)² / (2 * 60000 * 9.8 m/s²) = 2.4 m

      where 1701 m/s is Mach 5

      1. Paul Johnston

        I maybe wrong but:

        v^2 = u^2 + 2as (u=0)

        s = v^2/2a

        why have you include g which would account for the factor of 10?

        1. SkippyBing Silver badge

          g

          Err... because acceleration is measured in g so 60000g is 60000 * 9.8m/s/s

      2. Daniel Evans

        @AC Factor of 10

        Well bugger me, so I am. I declare my original question null and void.

        I blame google calculator.

  4. Magnus_Pym

    Question

    "but the Blitzer's projectiles are already finned - it would be comparatively easy to make them smart, "

    Is the making of smart electronics with the ability to survive the inside magnetic/electric environment easy?

  5. Anonymous Coward
    FAIL

    Yeah - High Performance Rah-Rah

    1.) S-400 has more payload, longer range, higher terminal speed and is agile.

    1.1) S-400 only needs 100g maximum acceleration.

    2.) Show me the Vector Thrust Control, Electronics and Sensors Which Can Take 60000g.

    3.) I have pleny of time to measure trajectory and launch my ESSM in the exact opposite direction for all long-distance (50km or more) launches.

    4.) Mach-8 devices are Very Hot. Infrared Sensors love this. My Stealth Glider is as cold as the atmosphere while slowly (80 m/s) gliding into the carrier and detonating 700kgs TNT.

    FAIL.

  6. Tom 7 Silver badge

    Can a rail gun be used to

    bring down rail gun weapons fired at it?

    I'm tempted to build one cos it looks like fun to a loony geek like me so are there any laws against it yet in the uk?

    1. Thomas 18
      Grenade

      Manufacturing a firearm

      The Firearms Act 1968 provides:

      57(1) In this Act, the expression "firearm" means a lethal barrelled weapon of any description from which any shot, bullet or other missile can be discharged, and includes -

      There are also laws covering airsoft guns, I think you need a liscence to manufacture them so I'd say you are out of luck.

  7. Anonymous Coward
    Terminator

    With Risks of being Owned by your own side!

    One of the drawback of such levels of EMP discharge on a mobile platform, either on land or sea will be the biological side effects on crew!

    (the US Navy already has prior history with messing about with High EMP projects on warships, they didn't go down too well with the crews health)

    The big Battle ships of WW2 also required evacuation of all open upper decks when the big guns were being fired or the shockwave would splash the crew over the bulkheads or overboard.

    Its in all likelihood that such ships will have to be fully computerised in both navigation and operation, simply due to the long term health risks to anyone onboard.

    such platforms would therefore be highly vunerable to cyber attack by hostile forces or BSOD!

    and god forbid if it decided that all surrounding fleet ships were designated as hostile!

    lets hope they use ADA as the next generation operating system to Windows for Warships.

    we welcome the arrival of our Autonomous Dreadnought Overlords

    1. Sorry that handle is already taken. Silver badge

      Re: With Risks of being Owned by your own side!

      "One of the drawback of such levels of EMP discharge on a mobile platform, either on land or sea will be the biological side effects on crew!"

      Really?

      "(the US Navy already has prior history with messing about with High EMP projects on warships, they didn't go down too well with the crews health)"

      Which projects were those?

      "The big Battle ships of WW2 also required evacuation of all open upper decks when the big guns were being fired or the shockwave would splash the crew over the bulkheads or overboard."

      That's because their projectiles were propelled by rapidly expanding gas.

      1. some vaguely opinionated bloke
        Coat

        "Which projects were those?"

        Philadelphia Experiment?

        Yes, the one that's just been degaussed, please...

        1. Simon R. Bone
          Black Helicopters

          er....

          which even Wikipedia lists as " widely regarded as a hoax" - oh look, what are those pretty black helicopters doing outside? Aaaaargh.....

  8. Anonymous Coward
    Anonymous Coward

    It surely is tactically relevant ...

    in the battle to transfer wealth from taxpayers to arms company CEOs

  9. Daniel B.
    Pirate

    Somalia Pirate Repellant

    If they were to fit one of these babies onto a tanker? One shot from this should take care of any pirate ship. And at a 200 mile range, it would also be a good patrol weapon!

    1. Jonathan Richards 1

      Can't be done

      ...for the same reason that a tanker isn't allowed to carry more conventional weapons. Once you arm a ship it isn't a merchantman any more, and many ports will not accept armed ships.

  10. horsham_sparky
    Boffin

    smart railgun dart? unlikely

    Great technology and article, I have been following this for a few years now. Just a point about this sentance

    "but the Blitzer's projectiles are already finned - it would be comparatively easy to make them smart, though the railgun would need to be aimed reasonably accurately to begin with."

    I see two problems with this. Firstly the acceleration is extremely high (60,000g from your article), much more so than conventional projectiles and even more so than missiles. A typical gyroscope (lets take for example the analog devices ADXRS453) is only rated up to 2000g powered or unpowered, so the act of launching the projectile is likely to destroy the controlling electronics, optics/radar/GPS etc.

    Secondly as its electromagnetically launched, the transient fields generated from this will be HUGE and will induce some high voltages onto any conductor (circuit boards, chips etc) within the dart. As an electronics engineer, I can tell you that designing electronics and shielding to deal with that is not a simple task, you could spend a long time just finding out if its possible.

    So in summary, Whilst it may be possible (with a hell of a lot of work), I would certainly not call it comparatively easy to make the finned projectiles smart. I felt the need to write this in case any misguided project managers at general atomics takes your article to heart and decides to give the local sparkies a hard time!

    yours respectfully

    pedantic electronics geek

    Note: no electrons were harmed during the creation of this educational missive, they were merely inconvenienced for a short period of time

    1. John Smith 19 Gold badge
      Happy

      @horsham_sparky

      "I see two problems with this. Firstly the acceleration is extremely high (60,000g from your article), much more so than conventional projectiles and even more so than missiles. A typical gyroscope (lets take for example the analog devices ADXRS453) is only rated up to 2000g powered or unpowered,"

      In the late 70's/early 80s there was a brief report in Practical Wireless (still in business AFAIK) about this artillery launched battlefield surveillance camera.

      Some years later I'm looking at solid state gyroscopes and receive a spec sheet from IIRC GEC at Loughton. They were supplying an unusual "Wineglass" resonator design and listed one of their design wins as "Professional grade camera mount." However they also listed it as having been tested to 40 000g. I suspect it was developed for the gun camera project. Impossible. No. Expensive. Probably.

      IMHO another S&M fiasco from the Generally Evil Corp. Tried to sell it at near mil spec prices then wondered why almost no one wanted it. So look out for it on Ebay for a fiver.

      "Secondly as its electromagnetically launched, the transient fields generated from this will be HUGE and will induce some high voltages onto any conductor (circuit boards, chips etc) within the dart. "

      IIRC rail gun electronics tends to use lots of hardware "floating" at high potential using things like solar cells and opto isolators to stop the electronics from being zapped.

      My guess would have been a high conductivity shell to ground the currents outside the electronics pack but also a magnetic shield of mu-metal to keept the field out (I'm not current. I seem to recall reports about amorphous metal films that can do a better job).

      The joker would be every sensor line into the package is a possible induced current path. How to keep the system safe during launch then enable data flow into the package.

  11. GeorgeTuk
    Stop

    Not really "leap-ahead"...

    ...its just evolution.

    Stealth fighter was possibly only leap ahead as no one had much idea about it. But still realistically someone was going to try it.

    Still very cool though.

    1. Charles Manning

      It is a leap ahead

      The rail gun PR teams have been struggling to find something positive to publish about rail guns for a long time. Being able to spin a semi-credible line is indeed a leap ahead.

  12. Bill Neal
    Thumb Up

    1 question

    "Blitzer's projectiles are already finned - it would be comparatively easy to make them smart..."

    How would one go about protecting "smart" innards of a projectile from the brief EMP caused while firing any rail gun?

  13. Anonymous Coward
    Terminator

    Warhead shocks

    I wonder how many explosive compounds are stable at 60,000g? Many high explosives work by transmission of the explosive shockwave from a trigger - 60,000g would likely do the trick too in many if not all cases - and for other compounds, I wonder how much friction heat is generated by their inevitable compression under acceleration?

    I think the first generation of these things are going to have to be hi-tec cannonballs - just very fast passive projectiles rather than proper shells, let alone smart ones...

    1. Chemist

      "cannonballs"

      Probably just pass straight through relatively thin skinned ships. Might be nasty but not terminal.

      1. Reg Sim
        Grenade

        I am sure it would be terminal for sombody...

        "Probably just pass straight through relatively thin skinned ships. Might be nasty but not terminal."

        I don't know about you, but having a 'cannon ball' punch threw one side of my cabin and out the other anywhere in the Mach numbers is gona cause me issue, from the pressure wave upto the fragments of my own hull.

        I do get your point however, that something akin to a holo-point would be more effective as it would make bigger holes as it tubles around.

        I wonder what a depleted uranium shell punching through the skin of a ship into its nuclear power-plant would do? - nothing good I reckon

    2. RJ
      Grenade

      Title..title, I think I have heard of titles

      When the depleted uranium / other heavy heavy stuff projectile is going at mach 5-7 You don't need explosives, kinetic energy does the job.

      1. Ian Stephenson Silver badge
        Go

        "Kinetic energy does the job."

        Particularly if the engine, fuel tank, magazine etc itself happens to absorb a small part of it ( The sea on the far side of the rapidly disintegrating object absorbing the balance).

        1. Alex Walsh

          Bit of Peter F Hamilton

          Much like the orbital bombardment by kinetic harpoons that happens in the Nights Dawn Trilogy really. The speed of the weapon causes the devastation as the energy has to go somewhere on impact.

    3. SkippyBing Silver badge

      That's the idea

      it just hits things really fast and relies on that to **** them over. Explosives would be overkill, plus it massively eases the onboard storage problem as you don't need to worry about accidentally setting them off.

    4. asdf Silver badge
      Boffin

      actually

      If you read stories of naval battles in WW2 it seemed fairly common for shells for example to go right through say a destroyer without going off or causing too much damage. When they did hit something or go off is when you read about all hands lost, etc.

      1. SkippyBing Silver badge

        re: Shells going through

        I was thinking about that, it might be better to just miss the ship and put all the energy into the water next to it, like a heavyweight torpedo that goes off under the ship rather than on impact. This creates a big bubble, various things I just about understand happen* in terms of it attaching itself to the ship et voila two bits of ship. Not 100% sure how that would work out in terms of the explosion being next to the ship rather than underneath but I think it might be a better idea than just punching lots of holes in it.

        *Like what it says here

        http://www.abc.net.au/science/articles/2005/09/01/1448475.htm

    5. John Smith 19 Gold badge
      Coat

      AC@00:45

      "I wonder how many explosive compounds are stable at 60,000g? "

      Pretty much everyone that launches in an artillery shell capable of air bursting.

      The granules are *solid* and tightly packed together in a single lump. As long as they are already resting on a solid base and *everything* accelerates together there is no problem.

      OTOH a small weight positioned above the explosive on a strong string which would snap if the load it carried increased by 60000 times *would* detonate most (if not all) known explosives by impact.

  14. Angus 2
    Joke

    Sheesh even the navies of the world

    are getting into this twilight/vampire craze. ;)

    I wonder if they settled on the generic "Vampire" rather than each radar/scanner operator (whatever they are called) calling out the name of their favourite bloodsucker whenever they detect an incoming missile.

    1. James O'Shea Silver badge

      err... no

      NATO's been calling inbound ASMs 'vampires' for more than 25 years. Way back in 1986 Tom Clancy managed to know that, when he wrote _Red Storm Rising_.

      Hint: the standard radar displays use stylized symbols to display various objects. Inbound ASMs are carets, ^s... upsidedown Vs. V for vampire. And inbounds also show up in red.

      1. Mephistro Silver badge

        @James O'Shea

        True. Greg Bear also uses this terminology in the first pages of Eon, written in 1985.

  15. Mephistro Silver badge
    Terminator

    A question

    They are testing this thing in land based facilities. Now, I would love to know how one of these would behave as a ship based weapon, because in the sea there are things like waves and constant vibration, plus the ship's movement. Moving the barrel while you are accelerating ammo through it at 60.000 gee doesn't sound as such a great idea -torque, momentum an all that. My bet is that, on a ship and under real battle conditions, one of these railguns will be able -with luck- to shoot once or twice. And then it will explode.

    "IMPORTANT ADVICE - READ FIRST: Before using the Blitzer, stop at a dry dock, sink the lower half of the ship in fast concrete and wait for a few hours" :D

    Yeah, I know, they're scientists and experts and all that crap. On the other hand most companies I know wouldn't say no to a little bit of money from a government, whatever the circumstances.

    1. SkippyBing Silver badge

      Normal Guns

      Are affected by all the wave stuff as well, that's why they have gyro-stabilising systems which keep the barrel pointing the right way while the ship moves around it. Anti-vibration mounts are already common, as are active anti-vibration systems.

      1. Mephistro Silver badge

        @ SkippyBing

        I understand your reasoning but I have some objections.

        Normal guns have a steel barrel, that confines the projectile. I read somewhere that big gun barrels suffer from some degree of deformation while shooting, as gyrostabilizers and antivibration mounts don't filter out everything. AFAIK actual railgun prototypes don't have any element for this role of physically constraining the projectile in a given path, leaving this part to the magnetism from the coils. My take is that the projectile, subject to lateral forces, would exert a huge pressure against the coils, and probably cause lots of heat in the process. And of course any physical contact with the coils themselves would destroy them, and probably the projectile and the weapon.

        And let's not forget that the acceleration this weapon provides is an order of magnitude bigger than that provided by naval guns, and the -ahem- barrel, is longer, providing yet more torque.

        And then there are 'battle conditions'. To be employed safely this system seems to need a ship in perfect conditions, something you don't usually find at a true war.

        I'm no expert in the area, just an anonymous armamentaphile, so I could be totally wrong, but I have genuine doubts about this system's ever working in a batleship.

        On the other hand, a land based railgun... mmhhhh... sounds great! :)

        1. SkippyBing Silver badge

          Hmmm

          I see your points, but I think you're overestimating the level of vibration weapons systems can be exposed to on a ship. Certainly it's probably no more than you'd get in a tank, although I'd imagine a static artillery piece may be better.

          At 2.4m I don't think it's longer than many large calibre naval guns.

          Having said that there's definitely a lot of work to do before it's a viable weapons systems, but then the first jet engines and guided missiles weren't that good either.

        2. Rattus Rattus

          @Mephistro

          It's a railgun, not a coil gun.

          The projectile rides through the barrel along a pair of rails, maintaining physical contact with them at all times. The acceleration is provided, via the Lorentz force, by the electricity conducted along one rail, throught the projectile (or it's sabot) and back along the other rail.

          So, yes it does indeed physically constrain the projectile.

    2. Charles Manning

      A bigger question

      Have they been able to make these rail guns sustain a reasonable rate of fire? Last I looked the rail guns were only good for a few shots before needing a significant maintenance job.

      No point in having a deep magazine if you have to switch out rails etc after a few shots.

    3. greggo

      for 3 millisec

      From info above it takes 3 msec to reach mach 5 at 60K G's. Give it enough mass (relative to the projectile) and a suspension system and it shouldn't be too hard to keep it sufficiently still during that time. Dealing with the reaction from the acceleration force is hugely greater than any issue with motion of the platform, is my guess.

  16. Deadly_NZ
    Pint

    railguns

    Or maybe they will look to space and build an orbital bombardment package ??

    I can see you whoooosshh bang

    not even time to finish the beer

  17. John Aislabie

    Pointless

    Mach 5 may seem fast enough to hit an aircraft but the maths says that it isn't.

    Consider a threatening aircraft with an anti ship missile say 20 miles away.

    If (having solved all the above problems) you fire a mach 5 projectile at that aircraft, it still has a a rather gentlemanly 20 seconds to decide to be somewhere else.

    Assuming it it is ambling at no more than mach 0.9 it has about 7 miles of possible lateral positions and over 3 miles of height to consider as the projectile races towards it.

    There are going to be a lot of misses. A lot

    1. Anonymous Coward
      Stop

      @Pointless: The Same Argument Can Be Made Against CIWS

      An ASM only one kilometer out from the ship must be tackled by Mach 3 slug from CIWS. The ASM has one second to jump 10 meters to the left, right or up. If high enough, down.

      The Russkies and others are clearly capable of moving a device 10 meters per second from no movement at all. Those who don't believe, look at the S-400 and ASTER videos on youtube.

      An interceptor like ESSM can correct its trajectory not just to compensate for wind and irregular fuel burnoff, but also for the movements of the incoming projectile/missile until the last few milliseconds. IR, Radar and ESM sensors and software will do that.

      If the projectile is unguided, software can calculate an intercept path and perform hit-to-kill. That's how SM-3 intercepts ballistic missiles. If the incoming "thing" is manoeuvring, ESSM will detonate its fragementation warhead and (hopefully) put at least one fragment into the "thing", thereby triggering the destruction of "thing".

      I am not "in the know" regarding ESSM software's hit-to-kill capability, but there is no reason why it should be impossible to create it.

      So maybe frigates will in the future have to house not just ESSM with fragmentation warhead, but also ESSM with a solid Uranium or Tungsten block for optimal hit-to-kill.

    2. Ian Stephenson Silver badge
      Grenade

      Actually rather a narrow cone...

      If it wants to hit the ship that is.

      Hitting the missile is the main target, should the plane get in the way of a hypervelocity slug then that's just bonus points.

      Planes dont tend to carry many antiship missiles at a time, soo 2 harpoons and a kamikaze run?

  18. Knowledge
    Grenade

    Thats a lot of effort...

    just to kill people, isn't it?

    1. Paul_Murphy
      Grenade

      That hasn't stopped people in the past.

      Just because it's more complicated doesn't mean people won't want to use it.

      Guns (especially flintlocks) are more difficult to use than bows and arrows, slower too - but we're not going to village greens on Sundays anymore are we?

      Hitting people and things with rocks has always been a popular way of getting your point across - all that changes is the size and speed of the rock.

      Grenade is a sort of rock...

      ttfn

      1. Ian Stephenson Silver badge
        Grenade

        "Guns (especially flintlocks) are more difficult to use than bows"

        Guns dont require as much muscle power, therefore cheaper to feed the grunts grain as opposed to good red meat.

        And having fired guns, bows and used a sling, bows are far more difficult to fire accurately than guns, slings an order of magnitude harder again.

        the musketeers are much easier to train than archers (go ask the sealed knot or other re-enactment group) to a usable standard, and dont forget it is easier to mass produce a gun than a english yew longbow.

        1. Tom 13

          Actually, I'm better with a bow (recurve, none of them new fangled compoung thingies)

          than a gun, didn't take all that long to become proficient with it either. Never tried a sling. Now what a gun does give you is longer range. These days, they are also a fair bit quicker than a bow as well. Last time I checked bows and rifles cost about the same at the local sporting goods store. Well, the ones worth owning at least. You can get those cheapy bows they use at summer camp for far less than a decent one.

          1. Ian Stephenson Silver badge
            Thumb Up

            @Tom13

            I'd lay bets you have put in a lot more hours on the bow than you have with a rifle though?

    2. Anonymous Coward
      Anonymous Coward

      Yes but

      It would be a lot of effort to kill people, but it's not about killing people. It's about providing high-paid jobs in the weapons industry. No one involved gives a toss about what it's all for, or even if it ever works in practice. As long as it jumps through the procurement hoops for the next tranche of money everyone's happy.

  19. bugalugs

    An 11 kg projectile at Mach 5 delivers a 1.79 MW splatter

    " GA is .. under contract to develop an Advanced Containment Launcher .... in 2011. These objectives include a launcher capable of .... muzzle energy of 32 MJ ( .... to support a 110 nmi mission) with muzzle velocities of 2.5 km/sec. This launcher involves the development of technologies appropriate for fielding tactically relevant containment with a bore life that exceeds 100 shots." A pretty picture of a bird's-nest-butted barrel accompanied.

    So, they are having the same Rail Self-Destructo problems the navy guys are...

    ps: welcome to our bear-aware continental defense observer. " sloppiness is faithful " works at so many levels.

  20. Anonymous Coward
    Jobs Horns

    Hmmm my psychic balls tell me...

    Yeah this thing is BIG.... just the barrel part, that can be made to rotate independently with all the capacitors etc., in the hull..... but It's leap of figmentatious proportions, just like talking to my balls, to be able to knock out a few slugs in rapid succession, in different directions and in the case of misses etc...

    It's also nice how when the US NAZI govt spits chips about it becoming common knowledge that their sleazomats are calling other folks piss pots and idiots, and her they are putting "Hmmmm blow up the images, measure with a micrometer, and do a simple reverse engineer" details up on the web of their super weapon....

    6 months the Chinese will have a better one at half the price.

    1. Naughtyhorse
      WTF?

      pardon

      thats all

  21. N2 Silver badge

    Aircraft & sea skimming missiles?

    Dont really represent a significant threat, some time ago there was a sign in the Phallanx maintenance department stating "If it flies, it dies" & it sure did.

    1. Charles 9 Silver badge

      Question.

      I've been hearing some of these "sprinting" missiles can do some pretty wild turns on approach and still hit target. Is this an exaggeration or does a CIWS have a means to compensate for such a weapon?

    2. Anonymous Coward
      FAIL

      @N2: And You "Downed" an Incoming SM-3 and a KEPD ?

      I guess not. You downed that ridiculous little fast propeller thingy.

  22. D. M
    Terminator

    Should be posible

    The interesting question is how fast it can shoot again in case the first one missed, it won't be much use if it can't reload/recharge fast enough.

    Now, make it small and potable (quake style weapon) or give us sharks with laser on their heads.

    1. Charles 9 Silver badge

      It may not have to be that fast...

      ...if it operates as part of a tandem pair. Either way could offer advantages. A staggered firing would provide a better opportunity to harass a target with a stream of rounds, while a simultaneous fire might be of help against more elusive targets--each could help the other to nail it even if it wanted to move.

    2. Tom 13
      Pint

      But why would you want to drink

      a rail gun?

  23. NogginTheNog
    Alert

    Sabot - friendly fire?

    Wouldn't want to be ANYWHERE half a mile in front of that bugger if there's a discarded sabot travelling at Mach 5 heading my way!

  24. Anonymous Coward
    Anonymous Coward

    Rail Gun accuracy

    Given the US reputation for 'blue on blue' I suspect any guidance system will be for show only.

  25. Anonymous Coward
    FAIL

    Why This Technology Is Not A Satellite Space Launcher

    First Reason: Too slow (Mach 8, Mach 23 Required)

    Second Reason: Aerial Friction in the lower atmosphere is gigantic at Mach 23. (or just Mach 8). Note that you must launch more or less horizontally, because that is the direction of the velocity vector you need for the satellite.

    Third Reason: The Launchpad needs to be 41kms long !

    echo "scale=20;(9*10^3)^2/(2*100*9.81)" |bc

    41284.40366972477064220183

    (assuming that your satellite (antenna ? semiconductors ?, gyro ?, heatpipes ?) can actually stand 100gs, as the "smart" S-400 missile can)

    Fourth Reason: I don't think they are able to shield the extremely sensitive electronics of the satellite from the gigantic magnetic fields and resulting currents. Shielding magnetic fields is much, much tougher than shielding electric fields.

    1. SkippyBing Silver badge
      WTF?

      Errr

      So you're saying it fails at doing something it wasn't designed to do? That's like saying a tank fails at being a jacuzzi. Nowhere did the article or GA say it was a satellite launch system.

      1. Anonymous Coward
        Anonymous Coward

        "FAIL" was directed at

        ..other commenters.

    2. Ken Hagan Gold badge

      Re: as a space launcher

      In addition to the previous reply, I would note that you've replaced the 60000g of the article with a figure 600 times smaller. There are useful payloads that can withstand that (like fuel and water) so if you really only need a 100m railgun to put stuff into orbit then you can be sure that the DARPA types are looking into it.

      On the other hand, air resistance is what we currently use to *slow down* a craft moving at orbital velocities, so what ends up in orbit might be a hot barrel of tea. Too hot for coffee, so I imagine the Yanks won't pursue the project.

  26. Anonymous Coward
    Coat

    Contest: name the ship carrying this weapon.

    Up to 5 suggestion per post.

    1- USS Stonethrower (or HMS Bouldertoss for UK, hehehe...)

    2- USS Gauss

    3- USS Crossbow

    4- USS Flintlock

    5- USS Ballista

    Ok I'll leave when we make port.

    1. Fluffykins Silver badge

      CAFBWAB*

      *Crafty Attack From Behind With A Brick

    2. Bigdecko
      Happy

      The Ships

      USS Constellation

      USS Reliant

      USS Valley Forge

      USS Enterprise

  27. Bigdecko
    Terminator

    WOW!

    Damn, I gotta get me one of those . . . .

  28. Fred Flintstone Gold badge

    Torque?

    Hmm. there are some mechanical challenges I can see on the horizon (yes, right next to that incoming missile). I'm going to be very interested how they will fight the resulting torque if they have to fire perpendicular to the ship's axis. Given the rather impressive acceleration forces it strikes me that this will generate enough torque to make the launching ship rotate along its length axis like a canoo. You need some *serious* water displacement to buffer for this.

    Rather good for comedic effect, not so good for maintaining a defensive position.

    Just musing - I'm sure someone must have though of this but I found no mention of it yet. Anyone?

  29. Russ Williams
    Boffin

    Interesting...

    As others have noted, Mach 5 with 60,000g means a ~2.4m barrel and ~3ms firing time. That's feasable for low/moderate sea states as any shock to the hull is unlikely to coincide with the instant of firing.

    Making the projectiles "smart" is a non-starter. The forces involved in the launch would crush all but the simplest and hardest electronics, would likely bend/break movable fins, and might even detonate the warhead. On top of that, it's going to be enough of a magnetic field (presumably on the order of 1 Tesla, like MRI scanners) to induce enough current to fry electronics and seriously limit the materials that can be used. In addition, it's non-trivial even to steer something at mach 5 - the air has the consistency of a brick wall.

    Under-sea blasts work fine for torpedos with a ton of high explosives. This sort of hittile would be maybe 1kg, with a muzzle energy of ~1.5MJ. Water has a specific heat capacity of 4,187J/kgK and a specific latent heat of evaporation of 2,270,000 J/kg. Assuming a sea temperature of 15 deg C it will take over 2.6MJ to boil 1kg of water - in other words, at 100% efficiency of conversion, the KE would be enough to boil only about a pint of sea water, which really isn't going to snap the keel of any ship that wouldn't fit in a bottle.

    As an anti-ship weapon, it's going to be limited to perforating the hull and hoping to hit something that'll go "boom". With a decent ROF and a lot of cheap shots, that could still be useful, but it's got to compete with 4.5" guns that can deliver a couple of dozen shells a minute out to 12nmi.

    Against Vampires the speed is a significant advantage as it means you can engage further out, which means that any deflection is likely to make the incoming ASM miss the target. While it's possible for a missile to jink to the side to avoid countermeasures, that takes a lot of energy, and it takes a lot of energy to correct the trajectory again afterwards - and so there's a finite limit to what can be done. Of course, you're firing a small, dumb dart a very long way - easy to miss a moving target the size of a phone box at several miles.

    Sadly there is one target which this weapon is ideal for use against: the SR-71 'Blackbird' :(

  30. ClammyLammy
    Happy

    Forget Smartness For Now

    No need for smart projectiles if you can get the guns to recycle ready to fire quickly and for a decent number of firings before needing service.

    Get a few railguns that can sustain a good rate of fire and do so for more than a few rounds and instead of one projectile (possibly) hitting the target at Mach 5, you can populate the general area of the target ship with lots of projectiles travelling at Mach 5 and (possibly) rip the thing to shreds.

    Or in the case of hostile aircraift/missiles significantly cut down or eliminate the number of options they have to course correct away from the threat. I think this was what Tool of Lucifer was saying in the first part of his rant.

    Personally I like the idea of railguns, they make me happy. But I can't help wondering what happens to the projectiles that miss as 200 miles is a long way to travel... Potentially into civilian coastal settlements.

    Maybe smartness is needed after all.

    Clam.

  31. Genesis
    Flame

    In a galaxy far, far away....

    Anyone else sensing that the Star Wars project might be still kicking and screaming somewhere in a back office in the Pentagon? High efficiency solar panel advances, rocket propulsion that uses minimal fuel and hyper velocity railguns seem like a good combination of technologies to shoot rockets out of the sky or even flatten military targets without sending in the boys in green (or tan brown in the current theatre).

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