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Navy To Deploy Lasers On Ship In 2014
Velcroman1 writes "The Pentagon has plans to deploy its first ever ship-mounted laser next year, a disruptive, cutting-edge weapon capable of obliterating small boats and unmanned aerial vehicles with a blast of infrared energy. Navy officials announced Monday that in early 2014, a solid-state laser prototype will be mounted to the fantail of the USS Ponce and sent to the 5th fleet region in the Middle East for real-world experience. 'It operates much like a blowtorch ... with an unlimited magazine,' one official said."
It's more complex than that. You want a laser in a frequency you can generate easily, focus well with optics, and that will not be absorbed by water vapor, gas, or dust. Higher frequencies don't necessarily net you any kind of energy efficiency yield (while per-photon energy is higher in higher frequency, you can just produce more photons for the same energy cost, so there is not efficiency gains from the physics). This [PDF warning] report gives quite a lot more technical details (including, yes, they do use IR), but not all of them.
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The reasons are simple - it is easy to build solid state IR lasers and hard to build solid state lasers at other wavelengths. The bandgaps of most of the convenient materials, which are easy to work with fall into the infrared region. This is also one of the reasons why do we use IR for fiber optic systems (850 nm, 1300 nm and 1550 nm).
What it can do is not run out of ammo.
CIWS has 1550 rounds in its magazine - about 20 seconds of fire. At which point you'd better be praying that the other side doesn't have anymore missiles to toss at you, since you can't reload a CIWS quickly....
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Probably both. The cross section for Rayleigh scattering (scattering from things smaller than light's wavelength, like atoms in the atmosphere) goes as 1/lambda^4, so longer wavelengths scatter much less strongly. This scattering is what makes distant landscapes look hazy, and the sky away from the sun look blue (scattering bluer light back towards the earth instead of letting it pass straight through); as you move to the red and near IR, you can get much clearer views of distant objects (thus also more effectively laser-zorch them).
The first airborne drone to be shot out of the sky with a (chemical) laser was back in 1979 or 1980 - there was a picture in Aviation Week. Interestingly, this was several years before the DoD admitted even doing research in the area.
There is lots of information on the web about all aspects of military lasers, what they work on, pictures and videos of tests, evaluation of every issue mentioned in every comment here. I've been following this topic casually for some time, and the data is out there. Google is your friend. But I know, nobody on /. reads TFA much less research the topic - not picking on you, this is just a general statement of fact. :)
I will note that the major 'win' for laser systems and to a lesser extent rail guns is logistics. A military organization is basically like UPS - it's all about getting parts, ammunition, fuel, and people delivered where it's needed. Ammunition in particular is a huge PITA - dangerous in transit, bulky, and dangerous when stored on a ship. The classic 'torpedo hit' in the movies is when the torpedo penetrates one of the magazines on a ship, which then explodes en masse, and the ship splits in two - or in dozens! The cost of delivering the ammunition to the ship exceeds the cost of the actual ammunition, and delivery of fuel is several times as expensive as the fuel.
For perspective, the guns on the old battleships like USS Missouri took several 100 lb. bags of cordite to fire off one shell. That's a lot of explosive. Eliminating that explosive makes more room for actual delivered shells, and eliminates a ship's greatest existential threat - an exploding magazine.
Using rail guns the only explosives would be whatever the shell being shot contains (which, if it is hypersonic, may be none - kinetic impact may be enough). Using lasers, a nuclear ship could essentially shoot continuously (at some rate) indefinitely - they would 'never' run out of ammo. So yes, this is still experimental. They are still working on increasing operational (as opposed to research) power output to the 100 KW range where things really get 'interesting'. But General Atomic already has a 150 KW laser running in research.
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Exactly, lasers just can't deliver enough energy fast enough to take out missiles or anything but the slowest aircraft. Range is also a major problem because the light is refracted and dissipated in the atmosphere. It's a demonstration of the technology, with the hope that it can be developed into something more useful.
The ill-fated ABL program solved both the energy and refraction problems, but that was a larger and more expensive laser (you can overcome atmospheric dissipation almost entirely if you can shape your lens on the fly to exactly counter the distortion of the atmosphere, which I believe is old hat for spy sats).
The equally ill-fated DDX program promised huge amounts of power to feed lasers and railguns, but I believe the type of engine that was proposed has since been abandoned, so I'm not sure where you could get enough power to take out a distant, large missile. It should still be fine for CIWS though.
As for NK's missiles, if they have the range to hit the US then they are virtually impossible to stop. Shooting down ICBMs is pretty much impossible to do reliably, unless you are able to somehow hit them all during the boost phase.
Not all long-range missiles are created equal. Sure, if NK is using a still-working Russian cold-war era ICBM, with all of its countermeasures, that's a hard target during re-entry. But they won't be launching "missiles", nor getting the advantage of MIRV, if they only have one warhead (which is one more than they likely have). If it's some homebrew NK-built missile, then it will be the easiest possible target (and last I heard we can hit those now), on the slim chance it even makes it across the ocean. Not a danger to ignore, by any means, but we've relied on deterrence for 60+ years now - any actual missile defense is gravy.
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This laser is probably in the 10's of kilowatts, and even including inefficiencies, it's a pretty small load. The air conditioning in the bridge probably consumes more power.
A two litre diesel engine generator would produce enough power and run for hours on a jerry can of fuel. That's pretty good going for a weapon.
And my personal fav, the Thunderbolt II - much more fondly known as the Warthog. God what a delicious tidy package of mayhem it packs....
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Until you get deployed to the SS Flounder...
I should probably clarify my earlier statement: Unit names and ship names are cool. Everything else is boring. Of course, in some cases, the names are also comedy gold. Take for example the British... they named a WWI ship the HMS Cockchafer. Yeah. A testament to miserable Britain if there ever was.
Erm, in proper English the "cock" spelling can often be pronounced "coe" I.E. cockburn is pronounced "coeburn".
Not sure how Cockchafer is pronounced but it's an European beetle.
But your point about the English navy is dead wrong. They have all the good ship names, HMS Resolute, Repulse, Victory, Indefatigable. Way better than the USS Alabama or Gerald R Ford.
Calling someone a "hater" only means you can not rationally rebut their argument.
Submarine named after a shark. Came to a rather bad end...
http://en.wikipedia.org/wiki/USS_Thresher_(SSN-593)
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