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Army Laser Passes Drone-Killing Test

Posted by samzenpus on from the zap-it dept.

Nerval's Lobster writes "Commercial package-delivery drones such as those revealed by Amazon and DHL could face danger from more than shotgun-toting, UAV-hunting yahoos following the successful test of a drone-killing laser by the U.S. Army. Though it's more likely to take aim at enemy observation drones than Amazon's package-deliver 'copters, the U.S. Army's High Energy Laser Mobile Demonstrator (HEL-MD) did prove itself in tests last week by shooting down 90 incoming mortars and a series of Unmanned Aerial Vehicles (UAV). The original goal during the test at White Sands Missile Range in New Mexico was to burn out or blow up mortar rounds and blind the cameras or other sensors carried by drones. The laser proved capable enough to damage or slice off the tails of target drones, which brought them down, according to Terry Bauer, HEL MD program manager, as quoted in the Dec. 11 Army announcement of the test. The quarter-sized beam of super-focused light set off the explosives in the 60-millimeter mortars in mid-flight, leaving the rest to fall 'like a rock,' Bauer said. The laser could target only one mortar at a time, but could switch targets quickly enough to bring down several mortars fired in a single volley. The laser and its power source are contained in a single 500-horsepower, four-axle truck but was directed by a separate Enhanced Multi Mode Radar system. The next step is a move from New Mexico to a testing range in Florida early next year 'to test it in rain and fog and things like that,' according to Bauer."

33 of 173 comments (clear)

  1. Reflective Armor by Kagato · · Score: 4, Interesting

    Laser, neat. Couldn't you just wrap the UAV in Mylar to deflect it?

    1. Re:Reflective Armor by stewsters · · Score: 2

      If you paint them red they go faster. If you paint them reflective, they don't get destroyed by the laser.

    2. Re:Reflective Armor by MyLongNickName · · Score: 3, Informative

      I'll give you two answers, feel free to pick the one you like.

      1) When you are fighting a less-advanced army, they won't have the technology to implement your suggestions.
      2) Defense (haha) contracts are written based on what will sell with congress, not necessarily what is useful

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    3. Re:Reflective Armor by iggymanz · · Score: 4, Informative

      No, reflection from a plastic with aluminum powder embedded in it is only partial, the remainder of the energy is turned to heat. These high powered lasers can bore a hole through a normal household mirror, by the way, for the same reason.

    4. Re:Reflective Armor by jmichaelg · · Score: 2

      How well a reflective surface would work would depend on the laser's power and frequency. Mylar doesn't reflect all frequencies of light and is imperfect at reflecting the ones it does. Pour enough joules onto the target and you don't care that 90% of them are being deflected - the remaining 10% will do the job.

      I've always thought that the ideal anti-mortar device would be a radar that told you exactly where the mortar round came from. "You shooting at us? Here, have a little present in return."

    5. Re:Reflective Armor by seven+of+five · · Score: 2

      1. No mirror is perfectly reflective; they all absorb some light. 2. Any crud on your mirror makes it even less reflective.

    6. Re:Reflective Armor by ShanghaiBill · · Score: 5, Interesting

      I've always thought that the ideal anti-mortar device would be a radar that told you exactly where the mortar round came from. "You shooting at us? Here, have a little present in return."

      This is know as counter-battery radar. It has been around for at least a few decades. I was in the Marines during the 1991 Iraq War (the one that made sense), and we had counter-battery radar then. When an Iraqi mortar fired, our 155mm howitzers would back-trace the trajectory and return fire before the mortar round even impacted.

    7. Re:Reflective Armor by lgw · · Score: 2

      As others have pointed out, nothing is perfectly reflective. But that somewhat misses the point: a reflective surface only helps against a low-energy laser: one that only damages through radiant heating.

      A high power laser weapon in the atmosphere is not a "beam of light" so much as a "column of exploding plasma". If you dump enough energy into the immediate environment of the target, it becomes very difficult to armor against.

      --
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    8. Re:Reflective Armor by techno-vampire · · Score: 4, Interesting

      Back in '72, when I was in the Navy, I worked on a radar-guided anti-aircraft missile. (Never mind which one.) Its on-board guidance was designed so that if you jammed the signals, the missile would home on the jammer instead. Not quite the same as what you're talking about, but similar.

      --
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    9. Re:Reflective Armor by Sique · · Score: 4, Insightful
      Yes and no. The 90% are only valid if the laser beam hits the object nearly at 90 degrees. Then indeed, the reflection will cause 90% of the energy to be reflected and 10% will be heating the surface. But still, this means we need to have a 10 times larger laser to have the same effect than on a non reflective (black) object.

      But in general, the beam will hit the surface at lower angles, and then we have to multiply the energy with the sinus of the angle. So if it hits the surface at 45 degrees, only about 71% of the energy will be transferred, and we need to increase the laser beam another 40%. And at lower angles, there is total reflection, and 0% of the laser will be able to heat the surface, as 100% of the energy is reflected. In general: if we build a drone like a stealth bomber with a shell of plane, mirroring facettes, laser beams will be rendered totally ineffective except for the seldom case that they hit the drone's surface at 90 degrees with 10 times the necessary energy.

      --
      .sig: Sique *sigh*
    10. Re:Reflective Armor by Tuidjy · · Score: 3, Insightful

      > If you paint them reflective, they don't get destroyed by the laser.

      You wish.

      Polished metal mirrors reflect about 90%. if you use some really expensive metals, you can push it to 95%. Milar, dielectric coatings, etc. can go up to 99.99%, but only in specific wavelength.

      Sounds great? Well, no. That's the reflection you get in vacuum, when the mirror is pristine. Now fire it from a mortar, have it heated by the air rushing past, and then apply even 1% of the output of the laser we're talking about. Your nice upper layer is gone, and your reflection drops like a rock... followed by the rest of your round, once the payload overheats and blows up.

      Very expensive reflective coating may buy you a fraction of a second, maybe even a whole one... but mortars are (1) cheap (2) slow to get to the target. So you just made each round a lot more expensive, and you still may not have bought enough time for it to get to the target.

      --
      No good deed goes unpunished...
    11. Re:Reflective Armor by Kuroji · · Score: 2

      Most mirrors are not perfectly reflective surfaces, despite how it might appear to the naked eye. The amount of light striking the mirror also causes heat build up, but the imperfections will reflect the light imperfectly if at all and your mirrored surface will now have larger imperfections for the laser to screw up. As this happens on a time scale of next-to-instant, well... you know.

      For the laser itself to be burned by the reflected light, you would need a mirror that is pointed specifically at the laser and at nothing else.

    12. Re:Reflective Armor by DigiShaman · · Score: 2

      Or just fire 10 times as many mortars! Sometimes more is better.

      --
      Life is not for the lazy.
    13. Re:Reflective Armor by Smauler · · Score: 2

      My energy saving idea as a kid was a room with perfectly reflective surfaces. You could just turn a light on for a millisecond, and the room would be perpetually light. Then I realised everything in the room would need to be perfectly reflective too. Not a problem, a cool suit could do that, I thought... but you'd have to have a gap for the eyes, so it would lose its efficiency. I also realised that although the room would be pretty energy efficient, it would not be very practical, and if the surfaces reflected more of the electromagnetic spectrum, a slightly nasty side effect would be that it would actually cook your eyes. I gave up on the idea.

    14. Re:Reflective Armor by CanHasDIY · · Score: 3, Insightful

      Maxim 37: There is no 'overkill.'

      There is only 'open fire' and 'I need to reload.'

      --
      An enigma, wrapped in a riddle, shrouded in bacon and cheese
    15. Re:Reflective Armor by jafac · · Score: 2

      simply replace the explosive payload of the mortar round with semtex or similar plastic explosive. Detonates from electrical charge, not shock or heat, like TNT. (also much more expensive - but with our defense budget, no expense is spared, right?)

      --

      These are my friends, See how they glisten. See this one shine, how he smiles in the light.
    16. Re:Reflective Armor by hairyfeet · · Score: 2

      Besides it really wouldn't be worth the bother as you could either spam the site from multiple directions, thus giving the tracking a lot harder time, or you could just use IEDs or suicide bombers which of course wouldn't be affected by your fancy laser.

      Every time I see new "super tech" like this all I can think of is Vietnam, the USA had tech light years ahead of the enemy...who then proceeded to make it so messy that the USA gave up and pulled out.

      --
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    17. Re:Reflective Armor by HornWumpus · · Score: 2

      If they spent the money on better brakes, I'm good with their choices. But I doubt that.

      --
      John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'
    18. Re:Reflective Armor by khallow · · Score: 2

      The problem with your assertion is that the US simply didn't have the political backing in the first war to invade Iraq. "Finishing the job" would create strategic problems such as fighting an insurgency with no support from anyone in the Middle East or the developed world.

    19. Re:Reflective Armor by EvilSS · · Score: 2

      If they spent the money on better brakes, I'm good with their choices. But I doubt that.

      That depends on if you consider spray-painted brake calipers an improvement.

      --
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  2. Really? by RightSaidFred99 · · Score: 2

    The laser could target only one mortar at a time,

    In the words of 15 year old sarcasm-meisters from 1989, "No Shit Sherlock?". Though I for one welcome the innovation of lasers which are broad enough to simultaneously detonate a bunch of mortars spread out over several hundred feet in 3D space.

    1. Re:Really? by barlevg · · Score: 3, Interesting

      Using beam splitters, you could in theory target as many targets as the laser can handle while keeping the beams directed. You wouldn't even need to have multiple targeting systems--I vaguely remember seeing a talk once (where the lasers were being used for optical trapping) where the beam pattern was controlled by a single piece of optics.

    2. Re:Really? by flaming+error · · Score: 3, Funny

      And using boat rudders, we could in theory target multiple tree-huggers with only one water cannon.

  3. Advantages of DEWs by barlevg · · Score: 4, Interesting

    Considering drones should be susceptible to conventional means of destruction (read: bullets, missiles), I was wondering why bother with directed energy weapons? The answer appears to be (1) discretion (because a drone dropping out of the sky is totally not attention-grabbing) (2) the ability to shoot through walls (okay, that's pretty cool), and (3) lower "cost per kill."

    1. Re:Advantages of DEWs by X0563511 · · Score: 2

      Also, you don't have projectiles flying off past the target if you miss or pass-through. If there's a friendly base, city etc beyond the drone, you most probably don't want to light it up with bullets or missiles.

      --
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    2. Re:Advantages of DEWs by C0R1D4N · · Score: 4, Insightful

      I don't think the laser beam has an arc and return trajectory.

    3. Re:Advantages of DEWs by barlevg · · Score: 3, Insightful

      Several things wrong with this.

      -More like cooked--these beams aren't visible spectrum.
      -Yes, I'd rather be blind than have a bullet to the head.
      -Cities and buildings shouldn't be in the linear line of fire of these beams (which will mainly be shooting up). The issue that X0563511 brought up is based on that obscure sciencey concept that things that go up usually come back down.

    4. Re:Advantages of DEWs by Sarten-X · · Score: 2

      Directed energy also has the advantages of a high rate of fire, easier reloading, and no recoil, and it travels at light speed. It's a better replacement for bullets in many situations, effectively firing as long as there's electricity, and burning a hole through practically anything, without needing to worry about travel time.

      --
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    5. Re:Advantages of DEWs by SirGarlon · · Score: 2

      Actually, discretion can matter depending on who the adversary is. Radar can theoretically track a missile or even a bullet back to its source; a laser is not traceable in that way. If, for example, one envisions fighting another well-equipped industrialized country, that could matter considerably. Air defenses that could fire without revealing their locations would have a an edge. (Unlike in science fiction movies, lasers do not make a visible beam unless there is smoke or dust to scatter them.)

      Since lasers propagate at the speed of light, there is by definition no way to know one is incoming before it hits. That's another advantage.

      --
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    6. Re:Advantages of DEWs by bob_super · · Score: 2

      Yes but that random airliner doesn't have wings designed to resist laser cutting.

      What? You mean I have to check behind the target just in case? That's against SOP.

  4. Targeting and Speed of Light ... by perpenso · · Score: 4, Insightful

    I was wondering why bother with directed energy weapons?

    With speed of light weapons the target does not move very far between firing and impact. Point of aim is basically point of impact, unlike bullets. No guidance system required, unlike missiles.

    Ammunition is unlimited as long as you have power.

    And because sci fi fans have been waiting for this since 1898. The War of the Worlds, H. G. Wells.

  5. Anti-satellite by perpenso · · Score: 2

    Also, you don't have projectiles flying off past the target if you miss or pass-through. If there's a friendly base, city etc beyond the drone, you most probably don't want to light it up with bullets or missiles.

    And for a "kill" in space you don't get the debris problem. Just a burned out image sensor on an otherwise intact spy satellite.

  6. Approaching useful power levels by Animats · · Score: 4, Interesting

    This isn't the first U.S. Army laser system that can shoot down mortar rounds. The Tactical High Energy Laser, in test since 2000, could do it. Here it is in action. That took three semitrailers of equipment and tanks for the chemical laser. Each shot cost $3000 in chemicals. Israel wanted to deploy the thing, even though it was expensive to operate, couldn't run for long, and not very portable. It was just too clunky for combat.

    The Army wanted a solid-state laser with that kind of punch, and now they have one. This new truck-mounted system uses a 10KW solid-state laser array. Probably a lot of small solid-state lasers. It might just be an array of 1000 standard 10-watt laser diodes. That's enough to take out artillery shells and small rockets. The only consumable is electricity.

    Beam weapons are about to become real. The most likely initial user is, again, Israel, which has to deal with small rocket attacks in known areas. Israel's Iron Dome system works reasonably well but uses a pair of $50,000 guided missiles to take out each $800 attacking rocket.