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The Military Technology

Warships May Get Lasers For Close-In Defense 482

Posted by kdawson
from the hot-in-here-or-is-it-me dept.
King Louie writes "Raytheon and the US Navy have successfully tested a ship-borne laser capable of shooting down aircraft. Video at the link shows the 32-kilowatt solid-state laser shooting down an unmanned aerial vehicle. The technology is apparently mature enough to be deployed as part of ships' short-range missile defenses, a role currently filled by the Basic Point Defense Missile System (based on the Sea Sparrow missile) and the Close-In Weapons System (based on a 20mm Gatling gun)."
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Warships May Get Lasers For Close-In Defense

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  • by flaming error (1041742) on Tuesday July 20, 2010 @02:33PM (#32968156) Journal

    Is it shark-mountable?

  • by keithpreston (865880) on Tuesday July 20, 2010 @02:38PM (#32968220)

    The best part is the Siemens Wind Energy Advertisment before the video. Apparently a with a few Windmills and a laser. Pew, Pew, Pew, we can finally have a green war!

  • 32 kilowatt!!! (Score:5, Informative)

    by Dios (83038) on Tuesday July 20, 2010 @02:39PM (#32968240) Homepage

    32 kW, not MW, thats kilowatt, not megawatt.

    • Re:32 kilowatt!!! (Score:5, Insightful)

      by Fuseboy (414663) on Tuesday July 20, 2010 @03:35PM (#32969044) Homepage

      Bullets and lasers deliver this energy differently - the bullet's energy is transferred to the target in a much shorter time (milliseconds, I assume) which produces more chaotic results than the laser (for the same energy), which is waiting until the target ignites or a hole forms, wrecking the aerodynamics. Even so, I was curious how the energy payloads stack up.

      A 32 kilowatt laser delivers (not surprisingly) 32kJ during a one-second pulse. I'm not sure how long this laser pulses, but from the video, it appears to be several seconds.

      By way of comparison, a .50 Browning has a muzzle energy of 15kJ, which is about the same as a half-second exposure to the laser.

      The Phalanx gun which this the laser purports to replace, on the other hand, shoots 20mm rounds - these could weigh 100g [wikipedia.org] each, for a muzzle energy of 30.25kJ, comparable to the one-second pulse. Of course, the Phalanx shoots 50-75 rounds a second [wikipedia.org], for a total muzzle energy/second of firing of a whopping 2269kJ.

      By coincidence, this is the same as the food energy in two Big Macs.

      • Re: (Score:3, Interesting)

        by holmstar (1388267)
        Interesting. By that logic, a Nimitz class carrier could bring to bear 208000kJ/sec (the reactors provide 208megawatts) assuming it had lasers large/numerous enough.

        That would, of course, cause power to be diverted from all other systems, but who among us wouldn't love the idea of being present in the control room and having the lights dim as the ship fires it's ultimate weapon.
      • Insightful indeed. (Score:5, Insightful)

        by jamrock (863246) on Tuesday July 20, 2010 @05:18PM (#32970676)

        Bullets and lasers deliver this energy differently - the bullet's energy is transferred to the target in a much shorter time (milliseconds, I assume) which produces more chaotic results than the laser (for the same energy), which is waiting until the target ignites or a hole forms, wrecking the aerodynamics.

        While energy weapons are gosh-wow sexy, their effects depend on maintaining the beam on the incoming missile for some undetermined length of time, until it either ignites the fuel or destroys the guidance systems. As modern ship-killer missiles tend to be supersonic, keeping the beam focused on a particular spot on an incoming missile is far from trivial, and of course will vary from missie to missile, so the defensive sytems have even more variables to account for. Phalanx and other gun systems use radar to track the incoming missile as well as the stream of outgoing rounds, and adjusts the aim until the tracks intersect.

        Another problem is that destroying the missile's guidance system alone won't cut it. If it's already locked in the terminal phase chances are it will be blind, but still hit the target. This is the major reason that CIWS tend to use multi-barrel cannon with extremely high rates of fire (20mm/6,000 rounds per minute in the case of Phalanx, 30mm/4,000 rpm in the Dutch Goalkeeper system, which is built around the gun used in the A-10 aircraft). The intention is to cause as much structural damage to the incoming missile as possible, either destroying it or rendering it incapable of remaining on course, and with a missile like the SS-N-19 Shipwreck, which masses 7,000 kg and travels at Mach 2.5, even if the guidance systems and warhead are nullified, impact, even from large fragments, can still cause catastrophic damage to the defending vessel.

        Then there's the energy requirements of a powerful laser, along with the transmission and control systems, massive cabling, fire-suppression, safety etc., versus self-contained units like Phalanx or Goalkeeper which basically just plug into a hole in the deck (oversimplification of course, but not by much). I am not a weapons expert, but personally I don't see the advantage of energy weapons over traditional gun systems for close-in defense.

      • by sjbe (173966) on Tuesday July 20, 2010 @06:10PM (#32971432)

        Bullets and lasers deliver this energy differently

        Completely true but there are other factors to consider, the most important of which is actually hitting the target. The most important advantage lasers have is target tracking. With bullets you have to consider two trajectories (the bullet and the target) neither of which is likely to be perfectly straight. With lasers you simply aim directly at the target which is a much simpler tracking problem to solve, especially with modern sensors and vision systems. No need to consider the effects of wind, gravity, aerodynamics, bullet speed, etc. This doesn't make it a trivial problem to solve but it does have advantages.

        I think the speed of targeting will be especially interesting and important against hypersonic cruise missiles. I'm curious how long it would take to destroy a missile approaching at 2000 m/s (mach 6). From the time the missile appears on the horizon a close in defense system would have 3-8 seconds to destroy a missile traveling at those speeds depending on how high it was mounted.

        Not to say that bullets/shells don't have advantages too. Tricks like proximity fuses obviously aren't possible with lasers.

        Of course, the Phalanx shoots 50-75 rounds a second , for a total muzzle energy/second of firing of a whopping 2269kJ.

        Only relevant if all the bullets all hit, which they pretty much never do.

  • Fricken ships! With Frickin laser beams!
    • Re:Fricken ships! (Score:5, Interesting)

      by Buelldozer (713671) <cliff@gind u l i s . n et> on Tuesday July 20, 2010 @03:14PM (#32968706)

      Laser beams AND rail guns. The USN is on the verge of becoming a very "SciFi" weapons platform. If everything takes twice as long as planned then by 2020 you're going to see USN ships equipped with both weapons systems. Rail Guns firing projectiles at OTH targets at 5600MPH and handling close in threats with Phalanx CIWS upgraded with LASERS.

      This IS the future.

      • Re: (Score:3, Interesting)

        by mjwx (966435)

        Laser beams AND rail guns. The USN is on the verge of becoming a very "SciFi" weapons platform. If everything takes twice as long as planned then by 2020 you're going to see USN ships equipped with both weapons systems. Rail Guns firing projectiles at OTH targets at 5600MPH and handling close in threats with Phalanx CIWS upgraded with LASERS.

        This IS the future.

        But completely useless against low tech diver and C4.

        I love sci fi weapons as much as the next geek but seriously. I wouldn't say "This IS t

        • Re: (Score:3, Insightful)

          by fractoid (1076465)

          But completely useless against low tech diver and C4.

          Even more pertinently, it's completely useless against a diver with some C4 who's blowing the hull out of some cruise liner full of rich fat people. Destroyers, aircraft carriers, submarines - they're all great for fighting another country, but we're rapidly reaching the point where no country could practically declare war on another without economically crippling itself.

          The future of warfare is between governments and small, mobile rebel groups. Terrorists, guerrillas, freedom fighters, depending on your

  • by Anonymous Coward

    Pointing lasers at aircraft might get the navy arrested.

  • Numerous advantages (Score:5, Informative)

    by crow (16139) on Tuesday July 20, 2010 @02:43PM (#32968288) Homepage Journal

    There are numerous advantages to using lasers instead of traditional weapons:

    *) Longer range
    *) Better accuracy
    *) Unlimited ammunition
    *) No pollution from spent weapons

    • by ascari (1400977) on Tuesday July 20, 2010 @02:50PM (#32968392)
      Yes, it's all fun and games until the enemy brings out... gasp! ... Mirrors!
      • One problem is that the reflected, scattered light can still be very harmful, easily blinding. I think the light can be blocked the eye with special goggles, but there's bound to be mistakes even when testing it.

      • Re: (Score:3, Informative)

        by Surt (22457)

        Perfect mirrors, with not a single imperfection that will melt them in a microsecond, which are completely dust free in spite of being outdoors.

        • by bananaendian (928499) on Tuesday July 20, 2010 @06:11PM (#32971446) Homepage Journal

          GASP! this is what gets moderated as insightful these days!

          So the laser took three seconds to burn a whole in the rather unreflective fuselage of the target drone! but would melt anything but a 'perfect' mirror in microseconds. But let us humor this point one moment further and calculate 32kJ / 3E6 = 0.032J ... some of my less intense emotions about this thread have more energy than that!

          And further down the thread these brilliant commenteers further apologise how 'perfect' the mirrors inside lasers are and their so special you cant possible coat anything but laser components like that. Narrow bandwidth my rearend!

          Try burning a freaking hole onto a polished (90% reflectivity) aircraft grade fuselage with your now 3.2kW laser. Absoption, melting point, mass, heat capacity, heat conductivity... I'll leave it all as an exercise to these enlightened enthusiasts.

          Humbly Yours
          Pissed off physicist

      • Your comment should be modded funny, not insightful. The kind of mirror you can realistically bring to a battlefield is not going to protect you from a 32KW laser aimed in your direction.

      • Re: (Score:3, Informative)

        by benjfowler (239527)

        And once the power of the incoming beam exceeds a certain threshold, the reflective surface doesn't do much good anyway. Ablative coatings would burn away too fast and add too much weight. From the POV of the attacker, all they need to do is increase power and/or dwell time.

      • Re: (Score:3, Insightful)

        by ImprovOmega (744717)
        Mirrors are a waste, and too tricky to deal with (not to mention being easily cracked by standard kinetic weapons). You don't care particularly where the beam goes as long as it's *not* going through the armor into vital systems. Ergo your best bet is probably going to be a highly reflective white paint. Then your armor underneath can be whatever to protect against bullets and the laser light gets scattered relatively harmlessly in all directions. Granted, 100% reflective paint doesn't exist yet, but wh
    • by AdmiralXyz (1378985) on Tuesday July 20, 2010 @02:52PM (#32968424)

      *) Longer range

      Not really. Lasers are strongly attenuated in air, especially in the humid air in marine environments. Trying to get around this problem is the reason we're just getting weapons like this now, as opposed to thirty years ago, and even now they're limited to short ranges.

      *) Better accuracy

      Yes and no. In order to heat up the target's surface enough to cause destruction, you either need to focus the laser on the exact same spot for long enough time, or just crank the power up and/or widen the beam enough so that it doesn't matter. The first has proven almost impossible, and so we've resorted to the second.

      *) Unlimited ammunition

      No. There are two kinds of lasers in consideration by the military: chemical and solid-state. Chemical lasers need tons of (duh) chemicals to form the reaction that generates the laser light, and when you run out, you're done shooting. Solid-state lasers require heavy amounts of electricity, which needs to come from somewhere.

      *) No pollution from spent weapons

      Again, no. Chemical lasers leave behind highly toxic waste products when the reactants are expended; that's the main reason why they're not in heavy use in the military today. Solid-state lasers leave behind pollution from whatever power source you use to generate the electricity.

      I'm not saying lasers are awful tools, they're certainly useful in specific applications. But they're not the Wunderwaffen you're making them out to be.

      • by Terrasque (796014) on Tuesday July 20, 2010 @03:31PM (#32968968) Homepage Journal

        From the article :

        Although Booen says that for security reasons he cannot divulge the distance at which the laser-based systems can shoot down incoming threats (or the UAVs' altitudes during the Navy test), he notes that the military would not be interested in the new laser technology if it could not at least double the range of existing weapons.

        That would imply that at least in this case it would give longer range and higher accuracy.

        Also, regarding the lasers:

        The Phalanx--a rapid-fire, computer-controlled, radar-guided gun system--used electro-optical tracking and radio frequency sensors to provide range data to the LaWS, which is made up of six solid-state lasers with an output of 32 kilowatts that simultaneously focus on a target.

        So they use the already-existing Phalanx platform for targeting and tracking. Also also:

        The weapon combines a 20-millimeter Gatling gun that fires at a rate of either 3,000 or 4,500 shots per minute, with radar to search for and track targets

        So it seems that the new laser weapon will supplement or replace the existing gatling gun, and they indicate the laser will more than double the effective range of the setup.

      • by BCGlorfindel (256775) <klassenkNO@SPAMbrandonu.ca> on Tuesday July 20, 2010 @03:50PM (#32969312) Journal

        GP said "Better accuracy"
        P said "No"

        Lasers ARE more accurate than projectiles, wind doesn't shift a laser's course. The need for greater accuracy with a laser is a power issue, not an accuracy issue. Nobody is arguing yet that lasers are fully ready and powerful enough to replace projectiles, just that we are getting closer.

        GP said "Unlimited ammunition and No pollution from spent weapons"
        P said "No"... to both

        Again, solid state lasers, which are the topic of the article have their waste and ammunition limited only by their power source. Seeing as these are being tested for naval deployment, it's a pretty sure bet the power source for these in any significant deployment is going to be a nuclear reactor. That means the "ammunition" supply cycle for the ships lasers will by measured in years, so yes, that is as good as unlimited. The waste is also limited to the size of the reactor vessel, again over that same number of years. Not terribly shabby. The only obstacle is getting the power on the lasers up high enough to be useful even in foggy/cloudy weather.

        • by kaiser423 (828989) on Tuesday July 20, 2010 @04:36PM (#32970040)
          Ah, you're correct for generic projectile to generic laser, yes.

          The Phalanx system by itself has a very good RADAR system behind it, and the outgoing bullet stream is identifiable by that RADAR. Basically, it becomes a very accurate system because the firing system doesn't need to know anything about wind, etc. It just pushes the az/el/range of the outgoing doppler objects (bullets) to the az/el/range of the incoming doppler objects (bad things). Any effects of wind, etc are just taken into account automagically.
        • Re: (Score:3, Informative)

          by Jonathan_S (25407)

          Again, solid state lasers, which are the topic of the article have their waste and ammunition limited only by their power source. Seeing as these are being tested for naval deployment, it's a pretty sure bet the power source for these in any significant deployment is going to be a nuclear reactor. That means the "ammunition" supply cycle for the ships lasers will by measured in years, so yes, that is as good as unlimited.

          Since the only Naval ships which are, currently, nuclear powered are aircraft carriers

    • by saider (177166)


      *) Longer range
      *) Better accuracy
      *) Unlimited ammunition
      *) No pollution from spent weapons

      *) Standard missiles can engage targets 50-100 miles away. Power on the laser is diminished the farther you go, making it practical for close in targets.

      *) Accuracy is better due to zero flight time. I wouldn't want to be behind the target, tho. I'm sure that the tracking is not 100%.

      *) Ammo is limited by the fuel on the ship.

      *) Just a big cloud of exhaust from the stacks.

    • Re: (Score:2, Funny)

      by Krau Ming (1620473)
      you forgot less kickback when fired...at least that's what happens in goldeneye 007 for N64 when i got the moonraker laser.
    • by Herkum01 (592704)

      Longer range & Better accuracy

      How do you figure? A laser can be disbursed by the atmosphere like any other light wave and just because it travels in straight line does not mean that it can effectively hit that target. Unless the airplane is flying in a straight line, it can miss just like anything else. Guided missiles are effective in that it gets close enough to the target to limit the targets options for evasion. Unless you have some super computer that perfectly track a moving target the whole

      • Re: (Score:2, Informative)

        A laser would require energy, how much energy, I don't know how much but I doubt it is a pair of double AA are powering the thing so lets not pretend it has unlimited ammunition.

        32 kW according to the fine article, and if the laser is mounted on a carrier it will be a pair of Westinghouse A4W nuclear reactors powering it. The number of shots one of these things could fire won't be limited by the power plant, that's for sure. On a cruiser or destroyer it will be powered by the ship's service diesel generators. Sure, the ship could run out of JP5, but at that point it's dead in the water anyway because that's what the gas turbines that turn the screws run on as well. Long story short

  • by HeckRuler (1369601) on Tuesday July 20, 2010 @02:43PM (#32968294)
    Man the laser-harpoons!
  • Seems like they had to hold the laser on the target for a long time until it worked. If you can keep a laser beam on target that long, you might as well use the laser to guide an effective, high explosive round to it.

    • by DragonWriter (970822) on Tuesday July 20, 2010 @02:55PM (#32968464)

      Seems like they had to hold the laser on the target for a long time until it worked. If you can keep a laser beam on target that long, you might as well use the laser to guide an effective, high explosive round to it.

      Depending on the duty cycle of the parts in the weapon laser vs. a painting laser, it could well be far more efficient, from a logistical point of view, to use this system than to expend some consumable weapon guided by a painting laser. Never underestimate the importance of logistics.

      It also could be more reliable, as you just have to keep the laser operating and on target, rather than keep a laser operating and on target and avoid a failure in the launching, propulsion, guidance, or warhead system of the separate passive-laser homing missile. Given the consequence of failure with you point defense system, even small differences in reliability can be a big deal.

    • Re: (Score:3, Interesting)

      by interkin3tic (1469267)

      If you can keep a laser beam on target that long, you might as well use the laser to guide an effective, high explosive round to it.

      Sounds like faulty reasoning to me. For one thing, there are many values for "a long time." If you have to hold the guidance laser on the target for 30 seconds, but the defense laser for 20 seconds, those are both non-instantaneous, but when you're talking about an enemy aircraft trying to bomb you, I'd assume that's a world of difference. Also seems like we might not want missiles certain situations, like maybe when the enemy aircraft are in close proximity to friendly aircraft. I'd also expect the eff

    • by brainboyz (114458)

      Re-pointing a laser: not so much work
      Re-pointing a missile traveling at mach 3, especially after passing the target: hard

    • Re: (Score:3, Interesting)

      by Dunbal (464142) *

      Seems like they had to hold the laser on the target for a long time until it worked.

            I wonder what happens when your target is rotating, thus not exposing the same spot to the heat... oh dear, did I just counter a multi-million dollar weapon system?

            I'm sure it works fine on drones that fly in a straight line and are painted black.

  • As a military contractor, I encourage the addition of new systems onto NATO ships.

    As a Mechwarrior fan, I say bring on the Clan-LAMS. 1d6 heat?

  • by by (1706743) (1706744) on Tuesday July 20, 2010 @02:45PM (#32968320)
    From the summary:

    ...shows the 32-megawatt solid-state laser...

    From TFA:

    ...which is made up of six solid-state lasers with an output of 32 kilowatts that simultaneously focus on a target.

    As my stat mech professor once said, "but hey, what's a few orders of magnitude between friends?"

  • Priorities (Score:4, Insightful)

    by copponex (13876) on Tuesday July 20, 2010 @02:48PM (#32968368) Homepage

    Nice. So, we don't have money for the unemployed, for the ill, or even for veterans benefits, but we can afford laser systems to shoot down planes for imaginary invasions.

    Seventy percent of the defense industry is a private set of corporations whose economic incentive is to discover (or invent) threats, and then sell the government the contract to fight this imaginary enemy. Sounds like a nice recipe for solutions that exacerbate the underlying problems, and not by accident [go.com].

    • Re:Priorities (Score:5, Insightful)

      by couchslug (175151) on Tuesday July 20, 2010 @02:59PM (#32968532)

      A corrupt defense industry is one thing, but opponents who would like to destroy warships date back thousands of years.

      Ships are (very) high value targets, which obviously merit beam weapons to defend against attack, and particularly so as UAV systems proliferate.

    • Re: (Score:3, Funny)

      by ArsonSmith (13997)

      well, the unemployed, veterans and the ill could build, man and be targets for these devices if they had even the slightest motivation to be useful.

    • by Spectre (1685)

      Your description could apply to all kinds of things equally well.

      Homeland Defense - First invent an imaginary enemy, then enact all kinds of policies, surveillance, and counter-measures to defend against it.

      Consultants - Invent an inefficiency in an industry then sell services, software, and plans to work around it.

      Home Cleaning Products Industry - Note that something might be dirty/infested and sell people the product to clean it.

  • I don't know much about lasers so perhaps someone can answer this:

    If I were to make a missile/plane/uav with a chrome coating, something mirror-like and reflective, would the laser still work?

    • Re: (Score:3, Informative)

      by slater.jay (1839748)
      I am not an optical physicist, but my understanding is that it goes something like this: even a very effective mirror isn't reflective enough to avoid absorbing a bunch of energy, which damages your mirrored coating, which leads to a faster rate of heat transfer, and so on.
    • by xmousex (661995) on Tuesday July 20, 2010 @02:58PM (#32968516) Journal

      the shark will still bite you though but nice try

    • Re: (Score:3, Informative)

      by gstoddart (321705)

      If I were to make a missile/plane/uav with a chrome coating, something mirror-like and reflective, would the laser still work?

      The usual response here on Slashdot is that since most of the mirror surfaces you're likely to get are irregular/imperfect, the heat from the laser would likely ablate (burn off) any mirror coating you have before it would do what you're thinking. In the case of chrome, it's not a perfect mirror, and it wouldn't work.

      I think you would need a very perfect mirror surface, and even the

      • Oh well, so use lightweight ablative coating. With the typical times of flybys / warning before missile hit, that shouldn't be much of a problem. For some bonus points, make the coating release a barrier (in whatever form - aerosol, plasma, who cares as long as it works)

        Real bonus points: add retroreflectors; they might work only for a short time and reflect only a small part of incoming radiation...but there's bound to be something delicate on the other end. For that matter - how hard millions of toy ballo

    • Re: (Score:3, Insightful)

      by Speare (84249)
      hoggoth's reply is snarky, but mostly accurate. They say it won't matter, but it depends on how fast you expect the laser to work. The chrome would reduce the effectiveness at first, but if the laser can remain trained on the same part of the target, then any microscopic flaws or dust on the chrome would heat up, causing the chrome to heat up, causing the chrome to become less reflective, and ultimately, doom.
    • Well, depends on the wavelength of laser light.
  • If they have to defend against Anti-Ship Missles [wikipedia.org]; perhaps lasers can do a better job of defending against 20 missiles coming in at mach 2.5.
  • Yes but... (Score:5, Funny)

    by bytethese (1372715) on Tuesday July 20, 2010 @03:01PM (#32968552)
    Can it make popcorn?
  • by Megane (129182) on Tuesday July 20, 2010 @03:03PM (#32968580) Homepage

    I see a great need for a UAV-mounted Jiffy Pop module.

    It is a moral imperative.

  • Chinese have developed and are testing the Dong Feng 21D missile, capable of accurately targeting and hitting a moving navy Aircraft Carrier from 2000 miles away. US experts are scared. Since capabilities of this missile are not fully known to US Navy, their strategy to combat it currently is SM-3 interceptor rockets launched from Aegis destroyers and cruisers that escort Aircraft Carriers.

    Problem with that is that the reloading capacity of these Aegis equipped ships isn't fast enough to protect against a v

    • by Renraku (518261) on Tuesday July 20, 2010 @03:52PM (#32969342) Homepage

      A carrier group would be the least of our worries if the Chinese decided to launch a surprise attack. It would have to be a surprise attack, because we wouldn't put our ships within range of them unless we had some plan or some way of negating the threat. Telling a few soldiers to rush a machine gun nest is one thing, but telling a large part of our navy to rush the equivalent of a machine gun nest is quite another. Carrier groups are NOT expendable unless that's our only option.

      The scenario could go two ways.

      The Chinese launch a surprise attack and there's an 80% casualty rate within a carrier group. We send a few hundred cruise missiles to rain down on their capital and shore line defenses while another carrier group comes to fill in the position. One side backs off when the other starts threatening to launch nukes.

      Or, the Chinese declare war on us for some reason and aside from a few slap fights and invasion of Taiwan/Japan/Korea, we don't see much action because we're currently tied up in the cat box of the Middle East. We damn sure don't send a carrier group into hell's maw to die to those missiles.

  • Obligatory (Score:3, Funny)

    by Punko (784684) on Tuesday July 20, 2010 @03:36PM (#32969062)
    Having success against targeting drone is one thing, but up against the living?

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