Slashdot Mirror
Warships May Get Lasers For Close-In Defense
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)."
Is it shark-mountable?
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!
20 miles isn't far for a 32 megawatt laser I think. 32 megawatts is a lot.
>> And what if it's a cloudy day?
Crank up Dark Side of the Moon and spark one?
32 kW, not MW, thats kilowatt, not megawatt.
Fricken ships! With Frickin laser beams!
Pointing lasers at aircraft might get the navy arrested.
There are numerous advantages to using lasers instead of traditional weapons:
*) Longer range
*) Better accuracy
*) Unlimited ammunition
*) No pollution from spent weapons
Man the laser-harpoons!
FTFS:
"The technology is apparently mature enough to be deployed as part of ships' short-range missile defenses"
Name...That...Autocomplete!
...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?"
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.
It would if the power involved wouldn't instantly cause any suspended water molecules to careen off to some other place than that occupied by the laser. When you're dealing with things that are powerful enough to bring down aircraft and missiles, some water vapor isn't a big problem. It's not the same as the headlights on your car.
I support the Slashcott and will not be reading or commenting from 2/10/14 to 2/17/14. Beta is steaming pile of dog shit
Presumably, the reason for replacing 20mm Gatling guns with lasers is, ultimately, about missiles. 20mm DU rounds, in quantity, move pretty fast compared to aircraft; but substantially less fast than one would like compared to decent missiles. Photons, while they lack the punch, are much zippier...
Now, since the only reason to adopt this(no doubt more expensive and power hungry) system is that offers hope against missiles, why testing against UAVs? Well, if I were an optimist, I would say that this is just one of the tests in the development process. If I were a pessimist, I would say that the fine folks at Raytheon are following in the time-honored tradition of anti-missile systems, and responding to the fact that the problem is hard by moving the goalposts until their system is up to the "task"...
Hopefully, well before deployment, it will see proper "red team"/"green team" type testing, where the opposing force, made up of the most devious and talented people at their disposal, is free to try every sneaky, optically confusing, silver plated, ablative armor protected, etc. hypothetical near future threat that they can come up with against the system. A very valuable learning exercise....
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.
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 effective distance would be different Maybe the lasers have a wider effective range, closer, farther, or both? Are the sea sparrows they're replacing laser guided?
Lastly, I don't know much about laser guidance systems, but couldn't there be countermeasures for laser guidance that wouldn't be possible for a laser boring through the plane? Seems like a plane shining a laser off of itself might be able to redirect the missile, wheras the plane would need to be coated in a very good mirror to deflect the laser?
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.
the shark will still bite you though but nice try
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 then I get the impression it wouldn't have the desired effect.
Lost at C:>. Found at C.
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.
[
Can it make popcorn?
I see a great need for a UAV-mounted Jiffy Pop module.
It is a moral imperative.
#naabhaprzrag, #sverubfr-000, #agi-fcbafberq, negvpyr[pynff*=' negvpyr-ary-'] { qvfcynl: abar !vzcbegnag; }
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 volley of Dong Feng 21Ds. So they are pretty much screwed. Currently Aircraft Carriers are the most effective way of projecting current US air superiority anywhere in the world. Imagine the implications of a bunch of US carriers being sunk.
This laser defense system may be Navy's answer to this new missile threat.
Red lasers on one side, blue lasers on the other. I keep forgetting which is which...
It's red lasers on the port side, green lasers on the starboard side showing from dead ahead to 2 points abaft of the beam. I thought everyone knew that.
This ain't rocket surgery.
This offers far less hope against missile swarms and fast cruise missiles then lead-spewing kinetic weapons. With this you need to affect a single point on the missile from the front for quite some time to get results. If it's a fast cruise missile with mach3-mach5 terminal approach, laser is useless - it simply won't have enough time to do damage. So is kinetic CIWS. Missile based CIWS has a chance as it can engage at decent range and score a one shot kill.
Against swarms, this is even worse. You have to burn every individual missile, retarget and burn next one. Even if by some stroke of luck you succeed in this titanic task and can get missile terminated in say 3 seconds of burning it (completely impossible with laser as weak in tests), all that opponent needs to do to counter it is to program missile to go into a spin in terminal stage, making it impossible to focus at a single point of the missile. Or install a high-albedo tip. Or just attack in a stormy weather where laser energy will dissipate into water droplets long before it hits the missile.
Kinetic CIWS like phalanx/kashtan on the other hand actually have a decent chance of shooting slow and small missiles of this kind down, as they can usually kill a missile in one-two hits and are largely unaffected by weather conditions. Missile CIWS are better, but tend to get overloaded with sheer numbers.
All in all, this is just a PR stunt to show US taxpayers that their money is spent on yet another hollywood-style toy with little room for real life applications. This is a weapon for space age and space warfare where weather does not exist and laser can be effective at far greater ranges.
I'm not a physicist but its effectiveness isn't entirely based on the substance it's shooting at but also the frequency of the laser. In other words just because you have a mirror which reflects visible light doesn't mean it will reflect infrared or another frequency range. Granted a laser only has one frequency.
"Swarm[ing] our aircraft carriers with airplanes and missiles" is NOT "asymmetric" warfare. That is your basic nation to nation warfare, where someone has the guts and sense of honor to fight in compliance with the rules of the Geneva Convention. Asymmetric warfare would be someone floating a civilian boat up the the warship and setting off a suicide bomb. Google "USS Cole (DDG 67) on October 12, 2000" for an example.
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.
Seven puppies were harmed during the making of this post.
That isn't really "asymmetric" in the usual sense. It would be two conventional army/navy/air force units hitting each other with the weapons of the day. Totally standard nation state stuff. Now, that said, it might be that such an encounter would be, for America's much prized and oh-so-very-expensive aircraft carriers, the equivalent of what happened to Battleships during WWII(where it was demonstrated, repeatedly, that the heaviest naval guns couldn't match the range of bombers and fighter/bombers, and that mounting a few perfunctory AA guns on your battleship couldn't do jack about that fact)... A few battleships survive as curiosities, or as comparatively cheap ways of bombarding basically supine near-shore targets; but they are basically all scrap, now.
An advance in missile technology that takes missiles well out of the targeting ability of phalanx guns could do the same for aircraft carriers, which would sort of demote the US navy from "scary" to "eh" in a few hours... Hence, presumably, the interest in lasers and railguns and suchlike exotic ultra-high-velocity stuff.
The more "asymmetric" possibility of anti-ship missiles would be that, if they can be built into suitably rugged and easy to use one-time-use packages, programmed just to hit the biggest ship in range, or the one closest to the direction it was pointed, when used, you open up all kinds of fascinating capabilities for whatever ragged non-state-actors you are using as puppets at the moment.... Missiles are more expensive than artillery; if you are going to be shooting lots and lots of them; but offer greater portability and one-time punch....
If, for instance, anti-ship missiles, in a package large enough to crack a modern warship at least enough to require it to return to port for repair(and to cook off the onboard munitions, if lucky) and small enough to transport on a civilian truck or smallish boat, pretty much every modern navy in the world would have to triple the onboard laundry facilities to deal with all the shitting themselves... Near land, any dinky little shack with a seaward-facing window could pop a missile at any second. At sea, any civilian fishing boat in range is a potential threat(but you aren't allowed to just butcher them all). One of those fiberglass mini-subs that they use for drug running, which probably peanuts for a radar signature and can just quietly move around on electric engines, could pop up and fire at any moment. It would get ugly...
A 32 MW laser would be a fine alternative to a gatling gun - 32 MW is a lot of power, you don't need to paint a single spot on an incoming missile. The laser in the video was just a few kW, and so took several seconds to kill a drone. The gatling guns also kill one threat at a time, and it takes time to get a few rouns into an incoming missile (the first few rounds usually miss, the gun tracks both rounds an missile on RADAR and corrects fire until it gets it right), and once you do the remains are still a serious threat that will cause real damage and casualties. A laser has a lot more potential to cause a catastrophic kill of the missile, where the remains aren't nearly as threatening (and all the fuel is gone) when the ship is hit.
But gatling guns deal with threats that make it past the missiles, and the advantage of the Sea-Sparrow-based defenses is you can launch all your counter-missiles rapidly against many incoming threats at once, at medium range. A laser cannon might grow into that role, but it would be much harder (and have enormous power demands, but then we do need to protect ships with nuclear power, so maybe that's OK).
The other nice advantage of a solid-state laser is that it's not used up after one engangement. The gatling guns require significant service after minimal use. Can the Sea Sparrow-based CIWS can be "re-stocked" at sea?
Socialism: a lie told by totalitarians and believed by fools.
"Yeah. Too bad, though, since dropping gravity bombs from planes had its heyday during 1935 to 1955."
There have been more (tonnage) dropped since 1955 than in the 2 decades you mentioned. (And thas even discounting JDAM's and laser guided gravity bombs. Of course nearly all of it was dropped by US or 'Allied' planes.
"Nobody's tried doing that for a long long time."
Not against the US navy, since it has always had air superiority since after the Vietnam war. However The Royal Navy suffered many hits during tthe Falklands war in 82. Only one warship was sunk by an exocet missile.
"What you do is stand off 20 miles and shoot a missile at the ship"
Hopefully the laser can hit the missile too. But I doubt anyone could get within 20 miles of a carrier battlegroup if it was in open water.
So..."if the heatshield is ablative, then after an exceedingly short period of time, the superheated air is now hitting the real surface and doing damage, no?" Or perhaps the idea behind ablative surfaces is exactly to dissipate far larger amounts of energy than it would be otherwise possible without them...it's not about absolute defense (it never is), just about changing the odds
Gases don't "burn of" - at most they can turn to plasma; which would be a great thing - it's not translucent.
And hey, if the baloons are released from some distance / are just floating there... ;p
One that hath name thou can not otter
Having success against targeting drone is one thing, but up against the living?
If only we could fall into a woman's arms without falling into her hands
If the missile is moving at mach 5, it really doesn't matter if the bullet is stationary or at mach 1, most of the KE is supplied by the missile itself.
Why is it that the proponents of "one nation under God" are so eager to get rid of "liberty and justice for all"?
This laser is 32kW, and it's already pushing the limits of solid state laser tech. 32MW laser is nowhere in sight for several decades, unless we make major breakthroughs in materials needed, not to even talk about power draw, which for current laser at 20% efficiency would be around 160MW for your suggested 32MW laser. And with increased power, the efficiency of laser installation is likely to decrease significantly.
You're gonna have some pretty hardcore power cabling, cooling system and a nuclear reactor to power that kind of a thing, not to even mention the epic size of a weapon. Cooling system alone will probably be bigger then a modern missile silo.
This replacing a small, localized and largely autonomous system that performs better in most conditions? I think not.
Comparing this to Sea Sparrows or any other ship based medium range SAM in any way other then augmentation is just plain foolish anyway. This caps at a few kilometers, depending on weather. It's a potential kinetic CIWS replacement (i.e. phalanx). It's in no way even a contender for SAM CIWS replacement. Not even because the tech isn't ready, but because the tech is unsuitable by default. Weather and fact that Earth is a sphere will make sure of this.
That's my point. This cheaper laser takes too long to destroy the target. An HE round destroys it instantly (at greater cost, obviously).
Plus, since it's new technology, they'll sell it at a 1,000,000% mark-up. I know, because I'm a defense contractor ;-)
Next, as a former soldier myself, I can tell you that we are very appreciative of the best equipment money can buy. You know, because it saves our lives and all. I figure that paying for that is very least I and the rest of the tax payers can do for those that are willing to lay down their lives so you can complain about it freely.
First of all, I'm not trying to denigrate anyone's service. I know many people feel that the wars in Iraq and Afghanistan are justified, and I blame myself as much as I blame the politicians and businessmen who exploit our armed forces for their own goals and benefits.
But what if you had been asked to perform your duty to your country by educating poor children (in foreign lands or at home), or to help build roads or work with communities to reduce drug problems, mentor troubled teens, or become a surgeon and work for a lower wage in a government hospital?
It seems odd to me that the same people who think using force and violence to impose our will on foreign nationals - and putting their own life at risk in the process - is patriotic, while any of the previous paragraph gets relabeled as communism or some other misnomer. A battlefield medic is a hero, while a government paid surgeon would be considered incompetent, even though they are the same thing. The whole thing seems nonsensical to me.
Why can't the pulse compression technology that's used for lasic lasers be used for military lasers?
If the problem is painting the same spot on a missile for a second or so, wouldn't it be a lot easier if a 0.1 second pulse is compressed down to a femtosecond so all the energy put into the laser over the course of 0.1 seconds is delivered in 0.000000000000001 seconds?
Need a Python, C++, Unix, Linux develop
Payload. Much of energy is wasted as such lasers have very low efficiency. You will have to dissipate around 4-5 times the energy you get on laser's focus around the laser itself as waste heat. When it's lasik, you have nice and low power ratings which can be cooled easily. When it comes to large powerful lasers, it is simply not doable with current materials. Your installation will simply melt down or even vaporise itself if you have to output the energy needed to burn through metal in that kind of a small time window.
And what if it's a cloudy day?
Then they use different weapons?
Did you think they were going to scrap all existing weapons and replace them with this thing?
But, the REAL question is, am I immature enough to deploy the technology as part of my cubicle's short range coworker defenses?
Why yes, yes I am.
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.
A few points:
The fiber lasers used in the demonstration can approach 80% efficiency.
A more realistic 500KW would shoot just about anything down and would easily be powered by ship or grid.
love is just extroverted narcissism
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.
Have a look at actual military spending figures world wide. If anyone is going to be using any swarming tactics, it's the US, not Korea or China. Land war, of course China is going to have more boots on the ground - but not more drones/missiles etc. at their current spending levels.
http://www.globalissues.org/article/75/world-military-spending
You ever wonder why the US is having economic problems? Here's a hint: Have a look at what happened to the USSR. Perhaps if less money was actually spend on weapons and technology to blow shit up, and more was spend on capital infrastructure that is actually useful for production, the US wouldn't be in as big an economic the hole it is these days.
where someone has the guts and sense of honor to fight in compliance with the rules of the Geneva Convention.
It doesn't seem to me that fighting to win with the lmited resources you have at your disposal implies a lack of guts or honour.
What he can't kill, he has sex on. Trent.
And therein lies the major problem with this laser. It took several seconds to blow up a drone, which presumably isn't optically shielded (ie. shiny).
"Shiny" materials typically provide zero defense against high powered lasers. They need to be specialized materials to become effective.
Not to mention that the faster the missile travels, the greater the atmospheric cooling.
That's true to a limit. Given that most anti-ship missiles travel at multiples of mach, the friction generated at this speeds typically, considerably heats the missile's surface. Furthermore, minor deformations at such speeds can cause catastrophic aerodynamic stresses and failure.