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Drone meets laser, end of drone.
April 9, 2013 1:34 PM   Subscribe

Navy saves $1,399,000 versus short range missle. For the patient I particularly appreciate the appearance of R2D2, with modifications, at about 2:50 minutes.
posted by rmhsinc (102 comments total) 5 users marked this as a favorite

 
10-12 closely-packed ballistic missiles are still cheaper than a ship.
posted by anthill at 1:41 PM on April 9, 2013


10-12 closely-packed cruise missiles are still cheaper than a ship.

Not if that ship has an effective defence against them. Lasers have shot down mortar shells. It doesn't matter how fast a cruise missile (or ballistic anti-ship missile) flies if it's far enough out to allow a laser to target it effectively, which is about angular velocity.
posted by fatbird at 1:46 PM on April 9, 2013


This declassified project summary of SDI, made in the early 90s, covers a great deal of the challenges one faces when intercepting targets like this, whether the are a drone, a fighter jet, or an ICBM.

It's interesting to see these weapon systems in their infancy almost 30 years ago, and how the changes in the world around them altered them over time to their current design.
posted by chambers at 1:49 PM on April 9, 2013 [2 favorites]


Rate of fire is a likely problem, especially with early units. It depends if these are chemical pumped excimers or something else. Excimers often have trouble with repeated fast short rates and low durability.
posted by bonehead at 1:52 PM on April 9, 2013 [1 favorite]


Our stealth B-2 bomber and F-117 fighter already look like something the Galactic Empire would fly. We're halfway to Stormtroopers (minus the abysmal small-arms accuracy). Ship-mounted lasers are just the next step.
posted by Celsius1414 at 1:54 PM on April 9, 2013 [2 favorites]


Where can I patent a mirror finish missile?
posted by Doroteo Arango II at 1:54 PM on April 9, 2013 [3 favorites]


Next up in China's arsenal: Really shiny drones, jets, and ICBMs encased in mirrors.

Checkmate, bourgeoisie!
posted by slater at 1:55 PM on April 9, 2013 [4 favorites]


Next up in China's arsenal: Really shiny drones, jets and ICBMs encased in mirrors.

The US radar detection folks will thank you profusely, I'm sure. ;)
posted by Celsius1414 at 1:57 PM on April 9, 2013 [8 favorites]


In 1981 I saw one of the prototype systems like this in action, although it was from the USAF and the laser was mounted on a plane. We also met the fellows who built the test drones and were told about some of the interesting targeting nuance. They said the most effective attack involved using the laser to cut the control wires connecting the servos to the electronics, but this wasn't very "sexy.' For a more impressive demo they left the gas tank nearly empty so it was full of fumes and used the laser to drill a hole in it, leading to a satisfying kaboom.
posted by localroger at 1:58 PM on April 9, 2013


I wonder how well that system works in the rain or in a sandstorm.
posted by Mei's lost sandal at 2:03 PM on April 9, 2013


Not if that ship has an effective defence against them. Lasers have shot down mortar shells. It doesn't matter how fast a cruise missile (or ballistic anti-ship missile) flies if it's far enough out to allow a laser to target it effectively, which is about angular velocity.

Maybe. Its not clear to me that we have the systems to handle LOTS of relatively unsophisticated (by current US standard) missiles. I dont know too much about this stuff but I wrote a paper about likely Chinese area denial plans for the US in the event of a Taiwan Contingency and came to the conclusion that they would likely go with targeting our infrastructure and overwhelming the AEGIS systems with hundreds of cruise missiles.
posted by shothotbot at 2:05 PM on April 9, 2013


This still doesn't answer the question of whether or not Kent has stopped playing with himself.
posted by zombieflanders at 2:09 PM on April 9, 2013 [26 favorites]


It's a good question, Mei's lost sandal; a related question is how well do drones work in sandstorms and heavy rain?
posted by Mister_A at 2:11 PM on April 9, 2013 [1 favorite]


Next up in China's arsenal: Really shiny drones, jets, and ICBMs encased in mirrors.

Eh, mirror casing would not be a problem whit a Neutral Particle Beam Weapon (about 3/4 into in my linked video above). The beam would burn though the material at a higher rate than the reflectivity could handle. Sandia National Laboratories' Ion Beam Lab that opened in 2010 has been developing 'things' and 'stuff' like this since it opened in 2010.

As those secretive 'Top Men' say: 'Stuff?' Yep. 'Things' too.
posted by chambers at 2:11 PM on April 9, 2013


My colorblindness* isn't helping me determine if The Atlantic actually links to the New York Times report they mention, so here it is just in case: Navy Deploying Laser Weapon Prototype Near Iran

* Shakes impotent fist at all the web designers who remove the frickin' link underlines.
posted by Celsius1414 at 2:12 PM on April 9, 2013 [3 favorites]


This still doesn't answer the question of whether or not Kent has stopped playing with himself.

Or how much popcorn these can cook.
posted by It's Raining Florence Henderson at 2:13 PM on April 9, 2013 [2 favorites]


According to this, we don't need to worry about rain so much. Sandstorms are a different problem.
posted by yeti at 2:13 PM on April 9, 2013


One nice thing about a laser weapon is that the targeting calculation is easy. You shoot at what you see, where you see it. All the kinds of things you have to worry about with AAA don't apply.

But the fire rate is an important issue: how much does it heat up, and how long do you have to let it cool before firing again?
posted by Chocolate Pickle at 2:16 PM on April 9, 2013


Rate of fire is a likely problem, especially with early units. It depends if these are chemical pumped excimers or something else.

I believe that this is a solid state laser, according to the text at the beginning of the video. Those are mutually exclusive, correct?
posted by Edgewise at 2:20 PM on April 9, 2013


Re: cooling -- you're on the ocean, so at least you have a massive heat sink. I figure if they can keep nuclear generators on a sub cool, they should be able to keep a laser cool as well. Then again, I don't know what the physical limitations are -- e.g. if a xenon based radiator can sufficiently pull the energy out fast enough.

Maybe they should talk to the LHC guys -- if anyone on earth knows how to keep something cool, it'll be CERN's thermal experts.
posted by spiderskull at 2:22 PM on April 9, 2013


minus the abysmal small-arms accuracy

That could be a feature rather than a bug in a certain games-theoryish way; you develop an army renowned for their inability to hit anything they aim at and you ensure that local populations have an immense disincentive to act as cover for insurgent forces: once the Imperial Stormtroopers arrive no one is safe. Fuckers might mess you up even if the insurgents are standing right in front of them yelling "here we are, come and get us" and you're standing directly behind them.
posted by yoink at 2:23 PM on April 9, 2013 [3 favorites]


A mirrored surface is not really going to help a whole lot when you get hit by as much of a megawatt of energy in a coin-sized radius.
posted by resplendentoops at 2:24 PM on April 9, 2013 [4 favorites]


Huh. Never thought I'd move to Missle Command, but, well, here I am.
posted by sexyrobot at 2:27 PM on April 9, 2013


A mirrored surface is not really going to help a whole lot when you get hit by as much of a megawatt of energy in a coin-sized radius.

Hmmmm, hmmmmmm, I see. O.K., I'm not a scientist so bear with me here if I don't have all the technical details ironed out but what would you say if we programmed the missile to shout "I'm rubber, you're glue" just as the laser beam was about to hit?
posted by yoink at 2:27 PM on April 9, 2013 [4 favorites]


What about a handy mirrored corner reflector to send it right back from whence it came?
posted by marvin at 2:28 PM on April 9, 2013


My dog would shit herself trying to catch a laser that big.
posted by COBRA! at 2:30 PM on April 9, 2013


what would you say if we programmed the missile to shout "I'm rubber, you're glue" just as the laser beam was about to hit?

They'd break out the sticks and stones, obviously. Or find some way to make your pants catch fire.
posted by benito.strauss at 2:31 PM on April 9, 2013 [4 favorites]


Or find some way to make your pants catch fire.

My money's on "lasers."
posted by It's Raining Florence Henderson at 2:37 PM on April 9, 2013 [5 favorites]


They'd break out the sticks and stones, obviously.

And that's what WWIV would be fought with, according to Einstein!

Or find some way to make your pants catch fire.

My money's on "lasers."

Circle of life, man. Circle of life.
posted by Celsius1414 at 2:44 PM on April 9, 2013


If it's solid-state, I wonder if it's a free-electron laser. If so, the Navy is well ahead of their 2018 target.
posted by bonehead at 2:50 PM on April 9, 2013


Those are mutually exclusive, correct?

Yeah, excimers are typically gas-phase (at least the ones I'm used to), but some of the high power ones, like the airplane one linked above are liquid, as I understand it.
posted by bonehead at 2:52 PM on April 9, 2013


I just dunno. A megawatt of energy into a small area? If I'm reading the graphs right here, then you can aim for around 95 percent reflectivity, so that means you're having to sink around 50 kW. Which is still an awful lot, but getting there. Let's add some diffusive countermeasures- ah, the fog of war - and perhaps we can get it down to 5 kW. Which is still a lot - but more, areally, than (say) the Shuttle copes with on re-entry? That's shucking off an awful lot of energy.

Arm wave, arm wave. But I don't think this looks like game over for the drone designers. It looks like stealth, which is a really clever and expensive idea that works so well until you deploy it - at which point, the other side just design something which doesn't follow your assumptions any more.
posted by Devonian at 3:02 PM on April 9, 2013


What about a handy mirrored corner reflector to send it right back from whence it came?

Something like that isn't very aerodynamic. I can't see how you could mount it on a missile, drone, or warplane and still be able to fly reasonably well.
posted by Chocolate Pickle at 3:04 PM on April 9, 2013


This is all well and good but can it pop a giant Jiffy Pop?
posted by Gronk at 3:09 PM on April 9, 2013


Will someone think of the cats..
posted by phaedon at 3:10 PM on April 9, 2013 [1 favorite]


I just dunno. A megawatt of energy into a small area? If I'm reading the graphs right here, then you can aim for around 95 percent reflectivity, so that means you're having to sink around 50 kW. Which is still an awful lot, but getting there. Let's add some diffusive countermeasures- ah, the fog of war - and perhaps we can get it down to 5 kW. Which is still a lot - but more, areally, than (say) the Shuttle copes with on re-entry? That's shucking off an awful lot of energy.

The thing is that any impurities get really absurdly hot and warp and discolor and now you're not reflecting 95% any more. Even a 300W halogen bulb will ruin itself if you get finger grease on it.
posted by aubilenon at 3:27 PM on April 9, 2013 [1 favorite]


Let's add some diffusive countermeasures

That wouldn't be practical on a stationary missile-sized object, much less even a slow-moving cruise missile.

than (say) the Shuttle copes with on re-entry? That's shucking off an awful lot of energy.

Your mirrored surface has no more the thermal properties of a shuttle tile than the shuttle tile has the reflective properties of the mirrored surface. Unless we're talking about some unobtanium that came out of an R&D lab in 2113.
posted by resplendentoops at 3:29 PM on April 9, 2013 [1 favorite]


Well, another facet of classic sci-fi explained (and later nods to it)
posted by ricochet biscuit at 3:30 PM on April 9, 2013


I feel safer knowing we are tirelessly maintaining our defenses against our own weaponry.
posted by klarck at 3:34 PM on April 9, 2013


Will someone think of the cats..

The ginormous alien cats? Way ahead of you.
posted by ChurchHatesTucker at 3:45 PM on April 9, 2013


If it's solid-state, I wonder if it's a free-electron laser.

No, the title card at the start of the video says the weapon uses commerical solid-state fiber lasers.
posted by RichardP at 3:47 PM on April 9, 2013


Maybe. Its not clear to me that we have the systems to handle LOTS of relatively unsophisticated (by current US standard) missiles.

Well, all of this is theoretical still, but you can see the shape of the future battlefield. Since WW1, the battlefield has been dominated by the effect of indirect fire--first artillery, then missiles, that allow an attacker to remain safe either over-the-horizon or behind a hill or just generally out of range of your direct weapons. In the 19th century men fought shoulder to shoulder in close drill to provide effective massed fire. After WW1, you had to disperse your troops or armor them or both. The maneuver warfare of WW2 was very much a response to the fact that anything that stood still or clumped up could be quickly and easily killed, while fast-moving, armored attackers could dominate any less mobile, less armored adversary.

If we have practical lasers, imagine a battlefield in which artillery is useless; a naval battle where missiles or planes are useless. It suggests that a pretty fundamental shift in warfare is starting. All those breathless articles about how Chinese ballistic anti-ship missiles render American carriers useless will need to be re-written, for starters.
posted by fatbird at 3:49 PM on April 9, 2013 [5 favorites]


Time to invest in IR-range metamaterials. They don't need to be capable of precise or broad-spectrum deflection. They just have to redirect enough of the energy around the target to hold off rapid thermal decomposition. If the surface can hold out longer than the components of the laser, you're golden.

Until they start firing at you with multiple lasers, anyway.
posted by dephlogisticated at 3:59 PM on April 9, 2013


Sure, but did the initial tests of this technology fill up a house with popcorn from a giant Jiffy Pop container inside it? I bet not.
posted by Chuffy at 4:25 PM on April 9, 2013 [3 favorites]


...and we see them on a ship, but is it too much to ask to put these on sharks?
posted by Chuffy at 4:28 PM on April 9, 2013 [3 favorites]


All those breathless articles about how Chinese ballistic anti-ship missiles render American carriers useless will need to be re-written

They needed to be rewritten when they were published. A carrier doesn't move fast, but it does move far enough during missile flight time to require significant guidance updates given that SBIRS is going to immediately detect the missile launch and the carrier isn't going to be moving in a straight line once missiles start flying.

The development of those capabilities and the deployment of the space infrastructure needed to make the missile a serious threat aren't going to happen on a short timeframe. If the Chinese start seriously developing that capability, the USAF would have the role of disabling or destroying the relevant space assets if shit got real. On top of that there is still the need to take into account the ongoing refinement and evolution of the SM-3 interceptor even without the specter of high energy laser weapons looming on the horizon.
posted by resplendentoops at 4:28 PM on April 9, 2013 [2 favorites]


Honestly, that video doesn't seem very convincing. The drone looks flimsy, and the distinction between the fire being caused by a futuristic laser beam weapon and a backyard sparkler seems pretty small.
It's scary and all, but, also, in this age of internet video fakery, it could just be smoke and mirrors to scare the Chinese.
posted by OHenryPacey at 4:31 PM on April 9, 2013


Yep, Real Genius.
posted by limeonaire at 4:34 PM on April 9, 2013


Though the video demonstrates the laser system's capability to bring down a drone, the weapon can also be set to "dazzle" other warcraft, a less detrimental attack that blinds the targets' sensors but does not fully destroy them.

Remember, gentlemen, it dazzles. Under no circumstances should this laser weapon system be described as having a stun setting.
posted by ionnin at 4:49 PM on April 9, 2013 [2 favorites]


Actually, while it's not shiny shuttle tile material is pretty darn reflective and it laughs quite effectively at very high temperatures. Also for shells rapid rotation would make it impossible to focus a really intense dot anywhere except the tip.
posted by localroger at 4:52 PM on April 9, 2013 [1 favorite]


Remember, gentlemen, it dazzles. Under no circumstances should this laser weapon system be described as having a stun setting.

One could also describe this method of non-lethal attack as a kind of "laser tag." Or "laser hair removal." Or even "laser fair," if you're French.
posted by It's Raining Florence Henderson at 4:56 PM on April 9, 2013 [2 favorites]


...a naval battle where missiles or planes are useless. It suggests that a pretty fundamental shift in warfare is starting.

None of this affects submarine warfare, which will certainly continue to be effective. Maybe your laser can stop a missile, but it won't be stopping a torpedo.
posted by Chocolate Pickle at 5:02 PM on April 9, 2013


Fast (supersonic if possible), sea skimming missiles with an ablative nose cone that spins during flight are a great counter measure versus a point defense laser

The horizon from the deck of a destroyer is about 12nm away. 12nm isn't very far. A missile traveling at the speed of sound can close 12nm in a minute. Fire 10 of these missiles and it only has 6 seconds to destroy each missile.

Putting an ablative nose cone on the missile (space shuttle tile material perhaps?) could help reduce the laser's effectiveness.

Lastly spin the missile during flight so that the laser is spread over the surface and can't focus on one point.

Shooting down a slow, high altitude, flimsy drone is totally different from shooting down a real missile. Let alone a missile designed to defeat laser point defense systems.

Lasers don't seem better than existing point defense systems (close in weapon systems) like phalanx.
posted by schwa at 5:09 PM on April 9, 2013 [1 favorite]


Or what localroger said...
posted by schwa at 5:11 PM on April 9, 2013


Probably also worth noting that even without any defenses at all, putting enough energy into a solid piece of metal like an artillery shell casing to make it even notice it's being heated is going to be very difficult. You will also have problems like vaporizing the surface if you can deliver enough energy, and the vapor then dispersing the beam. And if the solutions I was told about in 1981 were cutting wires and blowing up the nearly empty gas tank, what's the equivalent strategy for lasering an artillery shell that is headed in your direction?

The problem is that lasers aren't really Star Wars blasters; stuff doesn't magically explode because you hit it with a laser. Lasers are actually much better at cutting than they are at blowing stuff up. There are a lot of relatively simple countermeasures that make lasers nearly useless, with anything that makes focusing hard being much better than mirrors. My take on this is that it is just a gimmick that will prove not so useful in the field trial it's finally being granted.
posted by localroger at 5:23 PM on April 9, 2013 [1 favorite]


Fast (supersonic if possible), sea skimming missiles with an ablative nose cone that spins during flight are a great counter measure versus a point defense laser

Congratulations, your missile just survived beam contact for sixty-seven milliseconds until surface deformation and structural damage to your ablative surface reached the point where aerodynamic forces and centrifugal loads on the compromised area will be enough to finish the job of ensuring control loss and breakup. For reference of how well your ablative would have to perform to last that long, as a benchmark, in that timeframe the beam would have punched through forty-two centimeters of steel.
posted by resplendentoops at 5:33 PM on April 9, 2013 [3 favorites]


I think if we had lasers that could punch through 42cm of steel in 67milliseconds we'd have them mounted on tanks by now.
posted by OHenryPacey at 5:40 PM on April 9, 2013


Ok, so I have a prediction as to how this tech advances from my understanding (note IANA physicist, so those with the science please let me know where I'm wrong):

1) take a cruiser or destroyer class ship, and place an array of these lasers on it. Deploy several of these around a carrier group, and you have a decent defense against anti-ship missiles.

2) Take a lower-powered laser, and have multiple independently targetable lenses with a fast rate of fire capability. This would be used to mark targets with the laser, heat them up slightly or just tag them to separate decoys from real threats, and track them to take the workload load off of the main lasers. This would be effective against waves of anti-ship missiles fired against a carrier group, or providing cover for nearby aircraft. (going from the SDI counter-strategy of overloading the system with too many targets)

Now things get real theoretically shaky from my limited knowledge:

3) As far as protection against lasers, right now the only viable option I can think of (off the top of my head) is to artificially create some sort of diffraction layer in the air that could reduce the effectiveness of the laser. Now this tactic would seem to be only of use to a static or slow moving defender (let's stay with the carrier group example) against laser attacks from the enemy. An attacker would have to move slowly to make any on-board distortion effective, and then they would be more vulnerable to more traditional weapons.

So how would you create a diffraction layer that would protect you but not interfere with your own lasers? One could use the water itself as a shield, perhaps, spraying walls of water just outside the edges of the ship over critical areas, or using waves of sonic booms (several per second) to distort the air around the protected area. Each has it's obvious drawbacks, of course.

However, the shock wave from an attacking craft that alternates several times a second between the super and subsonic might offer some protection from the defender's lasers, but the stress on the craft would be considerable, and the nose would still be vulnerable. However, the nose is rarely the target - the thin walls of the missile's midsection are - at best you blow the fuel tanks, at worst sever rudder,engine, and engine nozzle control.

Since the current tech seems to be able to compensate for a supersonic bow shock currently, a dynamically changing shock wave might protect the midsection better with a slightly different body design to amplify the shock waves. Then you still have to deal with the extreme stress not ripping it apart anyways.
posted by chambers at 5:43 PM on April 9, 2013


This still doesn't answer the question of whether or not Kent has stopped playing with himself.

It's amazing how politically radical that movie seems now. I mean, why does Val hate freedom? Does he want the terrorists to win?
posted by ennui.bz at 5:46 PM on April 9, 2013 [1 favorite]


The thing about mirrors is they don't give perfect reflectivity. So a high-powered laser will burn through the reflective coating. It works even better if the laser works on a series of microsecond bursts.
posted by happyroach at 6:05 PM on April 9, 2013


So my dad works for the Navy in one of their other weapons divisions. Specifically, he's working on the answer to lasers: railguns. Go ahead and aim your laser at the solid chunk of mass coming at you, if you can. Even if you do get it and manage to deform it enough to divert it (doubtful), there are two more on the way.
posted by robocop is bleeding at 6:16 PM on April 9, 2013 [1 favorite]


Since this has me thinking about radiative processes, why doesn't the gas from the ablated material (be it designed to ablate or not) ionize and become optically thick from electron scattering? I tried to work out some cross sections but wasn't quite sure of what I was getting.
posted by kiltedtaco at 6:20 PM on April 9, 2013


why doesn't the gas...

From my very limited understanding, it does. But the laser is already have to basically drill through the atmosphere to get to your missile, so the power levels are already where gases don't do much against them.
posted by fatbird at 6:45 PM on April 9, 2013


Even a mile of atmosphere is very thin compared to the ablative discharge that results if you're vaporizing more than a fraction of an inch of metal, when you're talking millisecond timescales as you try to destroy something incoming.
posted by localroger at 6:50 PM on April 9, 2013


Specifically, he's working on the answer to lasers: railguns.

Best part? The all-electric drive and capacitor systems being developed apply to both. It's not either/or, it's both-and!
posted by the man of twists and turns at 7:08 PM on April 9, 2013


As Schwa says, this all comes down to measure and counter-measure, as always happens with new offensive and defensive technology. The issue here is that the defensive technology is radically cheaper than the offensive. What do I mean by "defensive technology"? Off the top of my head, how about
1) Spinning the missile - spreads the heat load away from the target spot, trivial to implement;
2) Ablative coatings - carbon/carbon composites will take 2000 C before starting to ablate and are cheap enough to use for brake pads;
3) Plasma producing coatings - the laser spot ablates the coating, the ablated material turns to a plasma that blocks the laser beam. This happens anyway, so enhancing the effect is trivial;
4) Stronger missile airframes - more heat needed to get each one to fail, again trivial in cost.

Each of these means the laser has to spend more time on each missile, decreasing the numbers of missiles that it can cope with. Maybe your $10 million laser can defeat a $10 million missile, but if adding $1 million in counter-measures means that you now need a $50 million laser, then lasers are a pretty ineffective way to deal with those missiles.
posted by happyinmotion at 7:15 PM on April 9, 2013 [1 favorite]


what's the equivalent strategy for lasering an artillery shell that is headed in your direction

Heat it until the internal explosives cook off. Does not apply to solid kinetic kill warheads, but for now people are unlikely to be shooting those at your ship unless you're very near the coast and the crazed commander of a T-90 or whatever they're up to now decides to send a sabot your way.
posted by ROU_Xenophobe at 7:16 PM on April 9, 2013


You can't steer a spinning missile. You might as well be launching an artillery shell, as you have no terminal guidance.
posted by kiltedtaco at 7:24 PM on April 9, 2013


I think if we had lasers that could punch through 42cm of steel in 67milliseconds we'd have them mounted on tanks by now.

Operational megawatt class laser weapon systems do not exist yet, but the progress of high-energy solid state lasers is moving fast enough to consider them plausible within a decade. That said, you are not going to be able to field that power level on a tank. Whatever descendent of the JHPSSL ends up in the F-35 won't be operating near that power level either. Big boats are another story.

You aren't going to be able to armor missiles or aircraft against those kind of power levels any more than you can armor a surface ship against a modern torpedo. No, ablative or reflective coatings wouldn't be cheap to integrate into a missile design, nor are they going to be remotely effective. The only way to survive is not to get hit. Which will pretty much mean saturating the integrated point defense network of the battle group with enough missiles that the multiple laser batteries and countermissiles can't stop them all. Which, of course, means you have to get something to survive long enough to get close enough to launch all those missiles. And how fast you want those missiles to go, especially right down at sea level, is going to dramatically impact their operational range.
posted by resplendentoops at 9:11 PM on April 9, 2013 [3 favorites]


We're halfway to Stormtroopers (minus the abysmal small-arms accuracy).

Self promotion and selecting the correct target makes a difference in what others think about how accurate you are.

The 1st thing Humans on Earth know about imperial Stormtroopers:
Obi-Wan: "And these blast points, too accurate for Sandpeople. Only Imperial stormtroopers are so precise."

And what happens when the target doesn't live in sand dunes and dress in robes?

When the 1/2 way there Stormtroopers who train with ammo are told to look for a Black Male in a grey Nissan Titan they instead shoot 45+ rounds at a blue toyota tacoma with 2 Hispanic women in it and miss both women with the bullets
posted by rough ashlar at 11:48 PM on April 9, 2013


Don't be too proud of this technological terror you've constructed.
posted by homunculus at 11:56 PM on April 9, 2013


One nice thing about a laser weapon is that the targeting calculation is easy. You shoot at what you see, where you see it. All the kinds of things you have to worry about with AAA don't apply.

except dumping that much energy into the air heats it, changing its optical properties, so there are different things to worry about. amusingly enough, a high powered laser will bend into a breeze due to the density differential between cold air entering the beam on one side and warm air leaving the beam on the other.

I think if we had lasers that could punch through 42cm of steel in 67milliseconds we'd have them mounted on tanks by now.

and they'd be trailing really long extension cords back to the giant generator sitting behind the lines? these things eat a huge amount of juice, which is available on a ship but not so much in a tank.
posted by russm at 1:53 AM on April 10, 2013


Whatever descendent of the JHPSSL ends up in the F-35 won't be operating near that power level either. Big boats are another story.
What about a 747?
posted by shothotbot at 4:39 AM on April 10, 2013


Whatever descendent of the JHPSSL ends up in the F-35 won't be operating near that power level either. Big boats are another story.
What about a 747?

At the point where you're planning on putting out enough power to operate one of these from several miles up in the air, why not go all-out and strap it to a satellite with its own nuclear power source? Then we can knock out Kane's Temple of Nod the terrorists from orbit.
posted by Mayor West at 4:47 AM on April 10, 2013


>10-12 closely-packed cruise missiles are still cheaper than a ship.

Not if that ship has an effective defence against them.


Even then. The key word here is "effective".

You have any idea how much a destroyer costs? Call it $1.8 billion. A cruise missile will maybe run you $1.5 million. And they travel at just under the speed of sound, around 550mph.

This is where math bits you in the ass. Lasers are direct fire weapons, so you need line-of-sight to hit a missile with a laser. Cruise missiles generally come in only a few dozen feet above the surface, and laser defenses are likely to be less than a hundred feet from the surface. That means that the apparent horizon is about twelve miles away. A cruise missile is going to close that distance in about eighty seconds.

How many missiles can one of these things shoot down in that time? One? Almost certainly? Half a dozen? Well this one took about fourteen seconds to destroy that drone, which is a lot smaller than a missile. But with improvements, sure, why not? But a dozen? That's only about six seconds per missile. That's one big honking laser. Twenty? With time for target acquisition, I'm thinking probably not. Just not enough time. A single missile strike is unlikely to sink a modern destroyer, but it's certainly going to ruin someone's day, and three or four hits could well do the job.

Okay, let's put four of the things on a single ship. Still cheaper than an equally-effective missile-based point defense system. Now we're up to eighty missiles. So let's do the accounting. On one side, nearly $2 billion worth of destroyer. On the other? $120 million in missiles.

This is actually fairly significant. It means that if they were able to ramp up this system so that it could shoot down a missile in ten seconds or so, our ships would be basically invincible against anyone incapable of throwing $120 million at the problem. So against a proper fleet action, we'd still be at risk. But against a terror cell or rogue state who got their hands on a handful of missiles, we'd be basically untouchable. As the former is far less likely than the latter, the math is a lot more promising than it sounds. The cost to kill a ship is still well less than a tenth of the cost to build it, but it's moved out of the reach of anyone without access to a well-organized, technologically-advanced industrial economy, say, Russia, China, India, Australia, Brazil, Japan, the UK, France, and Germany. Of which we're likely to go to war with approximately none. But there are dozens if not hundreds of whackjobs who might both be able to get their hands on a cruise missile or five and have the motive to actually use them, and suddenly they're no longer a threat. I'd call that worth doing.
posted by valkyryn at 4:55 AM on April 10, 2013 [2 favorites]


Best part? The all-electric drive and capacitor systems being developed apply to both. It's not either/or, it's both-and!

Yup! The goal is a ship with nothing explosive on board. Or at least, nothing as explosive as fuel for missiles, ammunition, etc. That means less armor and lighter/cheaper ships.

The laser stuff is not just for missiles and drones. The USS Cole attack shook up the Navy in a big way. Use the math valkyryn used above with cruise missiles and replace a 1.5 million bucks for a missile with 15k for a speedboat laden with explosives. My dad told me of meetings where ideas for countermeasures like expanding foam canisters were bandied about. Eventually, some uniform would get frustrated and ask why are they bothering with no-kill solutions against people who want to kill them? A suit would usually replay that the US can't sail into a port blowing up everyone who gets within X feet. A laser system, if it is quick enough, effectively shrinks the no-go radius around the ship to a much more politically reasonable distance, plus you don't have to worry about what happens if your rocket/torpedo misses.
posted by robocop is bleeding at 5:11 AM on April 10, 2013


That's only about six seconds per missile. That's one big honking laser.

No, that's a networked complement of ten or so lasers working in conjunction with radar.

This is a prototype - it's meant to test operational conditions on a ship on active deployment. The current emplacement is fairly large, the laser is relatively underpowered, but this is the first gen.

Missile technology, apart from some guidance or stealth improvements, is pretty much as evolved as it's going to get. The investments in increasing speed and payload are going to yield smaller and smaller returns, while laser technology is now at the stage where each generation is going to be an order of magnitude more effective.

Combined with the railgun, this will signify the end of the carrier and missile cruiser age, and a return to battleships.

None of this affects submarine warfare, which will certainly continue to be effective. Maybe your laser can stop a missile, but it won't be stopping a torpedo.

There's some really interesting ASW stuff going on right now, too... lots of fun to be had with modern SONAR transducers and computing horsepower.
posted by Slap*Happy at 6:48 AM on April 10, 2013 [1 favorite]


No, that's a networked complement of ten or so lasers working in conjunction with radar.

Okay, fine, but you're still looking at similar math. Most warships are warships, not point-defense platforms, and even the ones designed specifically for that purpose have a maximum number of usable hardpoints and power output/storage. There is a maximum number of incoming projectiles that any single ship can take down in eighty-ish seconds. Even if it's higher than twenty, it is always going to be lower than both (1) the number of projectiles that can plausibly be thrown at any given ship in a large-scale engagement, and (2) the number of projectiles it would take to equal cost of the warship.

Defense is awesome, but offense is cheaper.
posted by valkyryn at 8:30 AM on April 10, 2013


You can't steer a spinning missile

I don't see why not. It makes the avionics a bit harder but it doesn't have to spin very much either.

Anyway, in the approximately 60 seconds it takes for a missile to enter line of sight and close to the target a destroyer gets to move _maybe_ 0.5 nautical miles at most. You don't _need_ a heck of a lot of steering.

this will signify the end of the carrier and missile cruiser age, and a return to battleships.

How many times has that been trotted out since WW2? Every new naval tech promises to return us to battleship. Don't see it happening.

Yup! The goal is a ship with nothing explosive on board.

Except for all the fuel needed to run the generators that keep those giant capacitors charged up 24/7.

All of this is ignoring the fact that US Aegis class warships with their SM missiles (that can intercept targets _way_ further than the horizon) and Phalanx CIWS are already _very_ good at destroying incoming missiles. This lazer system is only a better Phalanx and is not a magic force field that protects ships from all harm.
posted by schwa at 8:36 AM on April 10, 2013


not a magic force field that protects ships from all harm.

Paging DARPA. DARPA to the white courtesy phone please.
posted by shothotbot at 8:45 AM on April 10, 2013 [1 favorite]


I'll take this seriously when they show me a video of this laser system working on a rainy day or against multiple shoulder-fired rockets fired by dudes on speedboats.
posted by snottydick at 8:48 AM on April 10, 2013


against multiple shoulder-fired rockets fired by dudes on speedboats.

Why shoot the rockets when you can just shoot the boats?
posted by valkyryn at 9:03 AM on April 10, 2013


You can't steer a spinning missile

I don't see why not. It makes the avionics a bit harder but it doesn't have to spin very much either.


Because it's a gyroscope.

Look, a lot of people in this thread are arguing very earnestly and completely out of their asses. I'm an optical physicist. I have burnt the shit out of some very shiny, very reflective mirrors with a sub-1W fentosecond laser.

We have here a demonstration of end-goal thinking: you want to demonstrate that the Department of Defense is run by sophomoric dopes who are more interested in securing jobs with defense contractors than they are in spending the nation's treasure. To that end, you're convinced that you, an IT guy in Mountain View or Austin, can see the obvious flaws in this defense initiative, based on your rigorous education reading Wired and Slashdot.

I've been involved in pitching projects to .mil agencies. I've been funded by the naval, army, and air force research labs. I'm trying to come up with a pitch to the Defense Threat Reduction Agency right now. These are not dumb people. The rigor with which proposals are vetted by these agencies is far greater than the NSF or other civilian organizations. Think about that next time you post something on twitter and yell 'Science!' like a dope.

The short answer to all of the objections made in this thread is that they require linear increases in performance for a point defense system. If you want to combat more incoming weapons, you decrease required-time-on-target for the bean by the same linear amount. And so on. Linear scaling is not usually problematic for engineers.
posted by samofidelis at 9:04 AM on April 10, 2013 [11 favorites]


MetaFilter: decrease required-time-on-target for the bean
posted by It's Raining Florence Henderson at 9:08 AM on April 10, 2013 [3 favorites]


Sorry - it was just too perfect a target.
posted by It's Raining Florence Henderson at 9:08 AM on April 10, 2013 [1 favorite]


Most warships are warships, not point-defense platforms, and even the ones designed specifically for that purpose have a maximum number of usable hardpoints and power output/storage. There is a maximum number of incoming projectiles that any single ship can take down in eighty-ish seconds.

Two or three ships networked together oughta do it. They already co-ordinate missile fire control this way.

More, these are lasers - no recoil. They don't need hardpoints, and do you even realize how much juice a modern gas turbine propulsion module produces? Shipboard reactors are an option if that's not enough.
posted by Slap*Happy at 9:15 AM on April 10, 2013


I think power production, storage, and waste heat management are going to be reasons big boats continue to be needed. Time to repeat shot, capacitor (or whataver) recharge times and waste heat dissipation are the big deals in these conversations, IMO.

How do you turn a nuclear and/or gas turbine powerplant, which are great at producing a constant power, into very high-demand short-term power? How big do those supercaps need to be (how likely are they to catch fire if you blink at them wrong)? How many do you need to fire 5, 20, 40 shots in a minute?

Where is all the waste heat going to go? Lasers are highly inefficient. Most of that extra power is lost to radiant heat---where are you going to dump those waste megajoules every second? Laser-based systems are likely going to be limited ultimately by how big a heat exchanger they can run. The ocean is a big heat-sink, but the rate of thermal transfer is something every high-energy weapon system is going to have to fight hard.
posted by bonehead at 9:38 AM on April 10, 2013 [1 favorite]


And how hot do you think the barrels of those Phalanx cannon get?
posted by samofidelis at 9:49 AM on April 10, 2013 [1 favorite]


You can't steer a spinning missile

Nit: Irrespective of its value in defeating energy weapons, there have been real-life steered missiles that were spin-stabilized. Dragon, for example, and I'm reasonably sure there are other guided anti-tank missiles that are spin-stabilized. At least for values of "guided" equal to "steered by a dude watching it go downrange."
posted by ROU_Xenophobe at 9:52 AM on April 10, 2013 [1 favorite]


Explosives are efficient at delivering energy to a target still. Even the best high-energy lasers are still below 10%. Projectile weapons are on the order of 1/3 to the shell, 1/3 to gas, 1/3 to barrel heating. This means that laser weapons have to be able to dump 90 to 95% of the total energy used, while projectile weapons have to dump only about 1/3---the 1/3 to gas is effectively already dumped.

Higher efficiency for projectiles also means that to get the same amount of energy on target, lasers weapons need to be more powerful, three to six times, based on the above math.

Both of those factors together, higher waste heat production, combined with higher-power needed to combat the native inefficiency, means that current generation laser weapons need to deal with roughly an order of magnitude more heat than similar-energy projectile weapons do. Unless lasers get a lot more efficient, I do think the thermodynamics of heat transfer will be a big deal for laser weapons, relative to projectile ones.
posted by bonehead at 10:08 AM on April 10, 2013


Dragon, for example, and I'm reasonably sure there are other guided anti-tank missiles that are spin-stabilized.

Neat. Looks like the idea was to fire charges on the side of the rocket, which presumably burned faster than the rocket could rotate.
posted by kiltedtaco at 10:23 AM on April 10, 2013


Explosives are efficient at delivering energy to a target still. Even the best high-energy lasers are still below 10%. Projectile weapons are on the order of 1/3 to the shell, 1/3 to gas, 1/3 to barrel heating. This means that laser weapons have to be able to dump 90 to 95% of the total energy used, while projectile weapons have to dump only about 1/3---the 1/3 to gas is effectively already dumped.

Your math makes no sense, as a laser can fire just as fast as it can be fed energy and dissipate waste heat, for as long as the turbines keep feeding it juice, where missile batteries do run out rather quickly.

The German Rhinemetal double-barreled models are already shooting mortar shells out of the air, in rain and snow, on something that can be vehicle-mounted. The Navy had a recent breakthrough in plasma weapons.

Energy weapons are just beginning their deployment - I don't see how missiles can keep pace. Their expense, rate of fire and reliability aren't anywhere near close current generation energy weapons, which are largely experimental.
posted by Slap*Happy at 10:32 AM on April 10, 2013 [1 favorite]


laser can fire just as fast as it can be fed energy and dissipate waste heat

Uh, that's exactly what I'm arguing, the thermodynamics of that heat transfer. That heat dissipation is a problem particular to (current) laser technology. It's a problem even with the watt-level lasers, let alone the kW and MW ones under discussion. I know certainly with excimer lasers, overheating can quickly reduce the efficiency of the energy production. Variations of even a few degrees in the lasing cavity can be a problem, at least in the systems I'm familiar with.
posted by bonehead at 10:53 AM on April 10, 2013


You can't steer a spinning missile

The Rolling Airframe Missile (nee Sidewinder) begs to differ.
posted by squorch at 12:07 PM on April 10, 2013 [1 favorite]


Wow, the farther down this thread I read, the more it sounds like the weapons systems from the Honor Harrington series by Weber.
posted by Gadgetenvy at 1:02 PM on April 10, 2013


The quest for a high power, electrically driven laser with excellent thermal management, lightweight packaging, and high brightness for tactical military applications may be realized with the advent of the Diode Pumped Alkali Laser (DPAL). The concept of using a gas phase medium for the phasing of large diode arrays via a highly efficient, cyclical photon engine combines the best features of electrically driven lasers with the inherent thermal management advantages of a gas laser.

I've noticed that the news reports on modern HEL weapons pointedly do not describe the type of laser used. (I've also noted, googling around, that the Soviets had laser tanks and laser frigates back in the '80s. Neither worked all that well. You better believe we've been working on this crap for at least that long. If they're going to the press to say that it works, it probably works.)
posted by Slap*Happy at 8:53 PM on April 10, 2013


If we want to be arguing on the basis of authority, then I'll point out that my thesis was on laser welding and I was burning holes in metal with kiloWatt lasers before MeFi existed. So let's confine our arguments to evidence, not authority, shall we?

The short answer to all of the objections made in this thread is that they require linear increases in performance for a point defense system.

That's getting close to the key point here - that what matters is the marginal cost to the attacker of any measure, set against the marginal cost to the defender of the respective countermeasure. How this cost-comparison works out in practice, we don't know yet and we won't until laser weapons and counter-measures are in widespread use. However, the fact that we can already point to a whole bunch of existing trivial-cost countermeasures suggests that lasers are expensive to build and cheap to defeat.

As for spinning the missiles, we already do it. Guidance is trivial. I can go and buy a solid state gyro that's 4 mm square, costs $20, and can cope with 2000 degrees/sec roll rates. That's consumer grade right now. Military stuff, obviously, is better.
posted by happyinmotion at 3:08 AM on April 11, 2013 [1 favorite]


Bur is that fast enough to do the terminal pop up/flare maneuver that anti-shipping missiles use? I don't know enough of the details for that kind of flight to more than hand wave.
posted by samofidelis at 4:07 PM on April 11, 2013


Oh, also, the problem isn't the internal gyro, it's that the entire missile effectively acts as one. You're throwing a spiral football, as it were.
posted by samofidelis at 4:09 PM on April 11, 2013


> short range missle

short range missile
posted by Sutekh at 5:06 AM on April 14, 2013


Why shoot the rockets when you can just shoot the boats?

Because you thought they were civilian fishing boats, right up to the moment when they turned towards you, pulled out the rocket launchers, and began converging on you by the dozens at high speeds.

I thought that may have been clear from the second linked article in my original comment, but in hindsight, I see that it could have been more detailed. Here's some more on the wargames in question...

Astutely and very covertly, Van Riper armed his civilian marine craft and deployed them near the US fleet, which never expected an attack from small pleasure boats. Faced with a blunt US ultimatum to surrender, Force Red suddenly went on the offensive: and achieved complete tactical surprise. Force Red's prop-driven aircraft suddenly were swarming around the US warships, making Kamikaze dives. Some of the pleasure boats made suicide attacks. Others fired Silkworm cruise missiles from close range, and sunk a carrier, the largest ship in the US fleet, along with two helicopter-carriers loaded with marines. The sudden strike was reminiscent of the Al Qaeda sneak attack on the USS Cole in 2000. Yet, the Navy was unprepared. When it was over, most of the US fleet had been destroyed. Sixteen US warships lay on the bottom, and the rest were in disarray. Thousands of American sailors were dead, dying, or wounded.

If the games had been real, it would have been the worst US naval defeat since Pearl Harbor.

posted by snottydick at 7:06 AM on April 15, 2013


Most of that extra power is lost to radiant heat---where are you going to dump those waste megajoules every second?

I am no physicist, but the ocean seems like a good candidate heat sink.

It used to work in MechWarrior!


I'll show myself out....

(very edifying thread!)
posted by snuffleupagus at 4:29 PM on May 1, 2013


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