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Navy's New Laser Weapon: Hype Or Reality?
Lasrick writes: MIT's Subrata Ghoshroy deconstructs the Navy's recent claim of successful testing with the Laser Weapon System. It seems the test videos released to the press in December were nothing more than a dog-and-pony show with scaled-down expectations so as to appear successful: "When they couldn't get a laser lightweight enough to fit on a ship while still being powerful enough to burn through the metal skin of an incoming nuclear missile, they simply changed their goal to something akin to puncturing the side of an Iranian rubber dinghy." Ghoshroy is an entertaining writer and an old hand in the laser research industry. He gives a explanation here of the history of laser weapons, and how the search for combat-ready tech continues: 'At the end of the day, good beam quality and good SWAP—size, weight and power—still determine the success or failure of a given laser weapon, and we're just not anywhere near meeting all those requirements simultaneously.'
Professor Hathaway was apparently foiled again
...another Shark-infested article...
I'm not up behind the science, but in SOME cases, can't lasers be deflected with mirrors? Now, the power level of the military lasers is HUGE, so perhaps the mirror idea wouldn't work?
I don't think the goal has changed, only the writer of the article is saying that. This test is basically a status report, which tells us they still have a long way to go. The real question is how much $$ and effort should they keep putting in?
But I will settle for space lasers.
Keep developing the technology. Keep deploying it. The Russians and Chinese would both love it if we abandoned the project. Eventually we will smoke these fools like marshmallows in a microwave.
Clown...
Laser guns, meh. Limited to line-of-sight. Railguns on the other-hand are a whole 'nother ball of wax. Designs for Navy vessels now have to focus more and more on supplying power (as in electricity).
-Matt
The power to destroy an Iranian rubber dinghy is insignificant next to the power of the Force.
I think a big advantage of lasers would be cost, as you wouldn't need ammo to fire it, just power (the Ponce's laser costs like $1 per shot). However, the ballistic advantage of projectile weapons is considerable.
LaWS is rather unique. Its just a proof of concept test to see if what they will encounter when they put a laser weapon on a ship operationally. This is a step past what they are doing with the X-47b. However, there are no 'X Planes' for lasers, really. LaWS ought to be viewed from that POV. OTOH, HELLADS is a step or two (or more) further along the technology curve than LaWS. Under current Pentagon procurement law, we'll have a laser weapon for ships and/or aircraft by 2020. If we didn't have to go through the insanity of that system, we could have one in a couple years. 2nd, I used to work at HELSTF. I regularly watched pundits claim things we did /that/ day were impossible with the current technology or that there was an easy counter to what we'd done (as if we hadn't tested that first). Talking heads, even ones which have some background in a subject, ought to be taken with a grain of salt. In fact, the BoAS has an axe to grind. Opposition to SDI-like weapons is historical at this point and ought to be taken in that light. Likewise, anything put out there by a defense contractor ought to be taken with an equally large grain of salt, especially one of the beltway bandits.
Do you know why the road less traveled by is littered with the bones of the unwary?
If you have a reflectance of X% for the wavelength considered, that means 100-X% is absorbed. Granted I am not sure how the reflectance of materials is at short wavelength but the weapon considered are at long wavelength compared to visible (the weapon considered seems to be around 1 to 2 micrometer in the near infrared https://fas.org/sgp/crs/weapon...). Source cite a reflectance of 94% to 98% for that wavelength for some type of mirror (silver mirror among others).
At such a 50kW Laser at 95% reflectance would mean 5% absorbance or only 2.5 kW. That means to give the same amount energy at the same distance for the same surface you need 20 time the same time. Or put in another way if you need to give 10.000 Joule to ablate that surface , you would need 4 seconds exposition rather than 1/4 of a seconds for a non reflective surface.
So where do I make an error ? Where do you see that the mirror would quickly lose the ability to reflect compared to exposure time ? Keep in mind that in the case of a balistic projectile, you only need to make sure the laser do not pierce the skin long enough that targeting would be hard. I do not see why you keep telling reflectance has no impact on such laser. It certainly has an impact on how much kW will the target absorb.
C. Sagan : A demon haunted world:
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visit randi.org
I would also expect that there is quite a few details to work out when it comes to mounting any new weapon on a ship and integrating it into the CIC. There is no reason to wait until you have a planet buster to get all that going and in place.
When Fascism comes to America, it will call itself Anti-Fascism, and tell you to give up your guns.
Energy weapon that travels at the speed of light? Not meh. A railgun projectile that travels slow enough that the target can evade before the projectile reaches it? Meh.
That makes no sense.
There never was a mission for the navy to shoot down nuclear missiles. there may have been a mission to shoot down anti-ship missiles. But they already had the Phalax and it is probably as effective as laser would ever be for that mission. But the drone situation changed everything. There wasn't a good way to deal with these, and the pinpoint accuracy of lasers combined with the low power requirements needed makes lasers the ideal weapon for this. Similarly, non-lethal weapons to fend off small craft boats are better solved by lasers than projectiles. Lasers are a great weapon for the navy since they have abundant power and cooling at hand. It means they can carry less explosives making their own vessels safer and reduces the logistics needed for re-supply.
What's remarkable to me is that in the 1970s the idea of a laser weapon seemed ludicrous since they deposited more energy into the laser than into the target, focusing through heated air was a problem, and simply rotating a large target (balistic missile) greatly increased the power needed to damage it. Now we have breakthroughs in laser diode efficieniency, and slow moving non-spinning targets with a low damage threshold
Some drink at the fountain of knowledge. Others just gargle.
A railgun projectile that travels slow enough that the target can evade before the projectile reaches it? Meh.
Shotgun railguns!!!
there are other uses for lasers that projectile weapons don't satisfy easily.
http://www.army.mil/article/82...
there a high peak power, low total energy, laser ionizes a trail from the laser to the target device. then you send a bolt of lightning down that air column, which continues to ionize it while it electrically destroys the target. This can be used to disable vehicles non-lethally from remote distances. It can even be used to destroy roadside IEDs.
Another use, in fact the one it was originally researched for in the 1990s, is discharging lighting storms. In the 1990s there were multiple outages of the internet and other coms systems with astonishing price tags, due to lightning strikes. These don't seem to be as much of a problem now, at least not making the news. But at the time it looked like our new electronic infrastructure would need protecting.
ships are the ideal laser platform due to their abundant power and cooling, as well as their weight carring capacity, sturdy rigid platform, limited storage space for ordinance. Moreover ships are a highvalue asset that in recent years have been denied access to coastlines (littoral) due to proliferation of cheap anti-ship weapons. so defeating those is important to the navy. the main drawback with lasers is you can't fire them over the horizon, and thus the longer range weapon will always bee needed as well.
Some drink at the fountain of knowledge. Others just gargle.
So, mister Ghoshroy, let's see your fancy schamancy laser . . .
I mean, the Navy's laser can't be mounted to a shark, or knock ICBMs out of the sky . . . sure, so what does YOUR laser do?
Oh, you have no laser? Wow, that NAVY laser looks pretty good, it's there and such, it DOES STUFF, yeah?
Sure, they didn't put it on a shark or anything, but this is the Modern Navy . . . they use Dolphins :P
Only if that target is the Flash.
Odd then that they already use Spinning missiles beacuse they help solve the re-entry problems
Some drink at the fountain of knowledge. Others just gargle.
Designs for Navy vessels now have to focus more and more on supplying power (as in electricity).
I believe the DDG-1000 series was supposed to address that, I remember reading about the power system and how it was modular enough to allow virtually all power to be directed to any particular system. "All power to weapons."
"Our two-party system is like a bowl of shit looking at itself in a mirror." - Lewis Black
Non line of sight attack. A rail gun can hit a target 100 miles out(impossible for surface level lasers). In seconds. Dodging isn't practical.
When ou have long line of sight you are correct. But lasers are limited to 10 miles or so.
i thought once I was found, but it was only a dream.
It's probably too heavy to fit onto an Arleigh Burke AEGIS destroyer. The Arleigh Burke AEGIS destroyer has been around for a long time, but they can't squeeze much more stuff into it. The Navy is probably going to have to design a ship specifically to accamodate laser weapons and railguns. The DDX might be suitable.
Only if that target is the Flash.
The posted advantage of a railgun is it's range. At the extremes, time of flight for the projectile is probably long enough that it can be evaded. Of course, those extremes are beyond what you could even fire the laser at in the first place. If i've learned anything from Eve though, it doesn't hurt to have railguns AND lasers.
You can extend the length of that "short order" by spinning the target.
Even if that would work you would have to:
1) spin the target in a useful rotation (difficult when target is being hit head on by laser)
2) have enough surface area to allow energy dissipation between rotations.
3) be able to dissipate energy fast enough or absorb sufficient energy for any rotation to actually matter
4) hope that the laser cannot maintain it's ability to target a single point for a length of time that matters
5) be able to practically coat the target with a mirrored coating
6) that the mirror could somehow retain sufficient ability to reflect in the face of environmental factors.
I'll add that maybe what is most impressive is not the laser power, but the control system required to keep the beam on a moving target at a mile away. The author seemed to miss that part of the technology.
That's actually rather easy. The navy solved that problem decades ago for ballistic trajectories which substantially more complicated computationally. Line of sight targeting is FAR easier with modern computers. That is why they use lasers to paint targets for missiles to home in on a target. It's much easier to target something with a laser which is not meaningfully affected by gravity or wind or time to intercept.
I think the really impressive bit would be how they could keep the laser operational in an environment as hostile as the ocean. I would think that the ambient salt water would be seriously challenging towards keeping a laser functioning optimally.
I think currently demonstrated ship-mountable railguns can emit a 7+ pound projectile at Mach 7. More to the point, these can be kinetic projectiles, meaning no explosives required, and there's more room for other things like, oh guidance systems.
Good luck evading that.
-Matt
The real advantage of lasers is speed of light - perfect for anti-missile weapons. Shoot them when you see them and move out of the way.
excitingthingstodo.blogspot.com
At 5000mph, a projectile 100 miles out will have 66 seconds to respond. Closer in, far less. Still, for an enemy craft width of, say, 300 feet would need to move 150' to avoid collision. At 0.1g lateral acceleration, fairly trivial, you could move an H-4 Hercules out of the line of fire in just over 3 seconds. That's a 5 mile range for the largest (wingspan) plane in the world. And from 6 miles out, the EM signature from a rail gun would be pretty obvious. That's very practical if the target is equipped with an automatic avoidance system.
Now if the projectile is active it does make things more interesting.
Is it just my observation, or are there way too many stupid people in the world?
I am jsut stating that it should help. A bit. In fact in a link above it is shown as a counter measure, as well as rotating the balistic projectile. Both combined would make it far far easier to avoid the laser burning thru... For a much cheaper price than such a lser system itself.
C. Sagan : A demon haunted world:
http://www.amazon.com/gp/product/0345409469/
visit randi.org
Can it create a chain reaction popcorn burst and wreck that guys house again?
Humor aside, as you point out targeting is not the problem here. TFA points out the problem, and questions whether or not there is actually a solution. Given the little video I saw, the laser is no different than the Air Force's airborne laser which failed.
Nifty, and sure.. some R&D should go into these projects. R&D != trying to fit a ship with something that has a range of about 1 mile on a clear day. Lasers are subject to all kinds of atmospheric issues.. including a very common thing on the Oceans called "FOG".
Missiles have much longer range, less requirement on perfect weather, and are far far cheaper.
-The wise argue that there are few absolutes, the fool argues that there are no probabilities.
Energy weapon that travels at the speed of light?
requires line of sight and fails in heavy rain snow and thick fog, sandstorms.
A railgun projectile that travels slow enough that the target can evade before the projectile reaches it? Meh.
only consider slow when your comparing it to speed of light, when conventional weapon (missiles rockets bullets) it fucking super fast,
and things you are likely to target with a rail gun like many like fortification, buildings bases, cities don't move at all or don't move fast enough like aircraft carriers battle ships.
they are both good weapons for different things. You use your laser to stop missiles and planes and use your rail-gun to turn the air field and missile silo into a smoking crater.
---Saying gnome 3 is better than windows 8 not so much a compliment as it is damning with light praise.
Traveling at Mach 7, it takes more than a minute for a projectile to travel 100 miles. Plenty of time to dodge. Radar can detect the projectile as soon as it appears over the horizon. Depending on altitute, that could be as soon as it's fired.
Yep. That's more likely the areas of application.
It takes more than a minute for a projectile traveling at mach 7 to travel 100 miles. Plenty of time.
How maneuverable do you think an object traveling at 5328mph can be without scrubbing lots of speed?
"Not much else is known: Its power is strangely classified, but the laser likely operates in the 15 to 50 kilowatt range" ...
"It also presumably excludes the cost of shipboard electrical power, likely in the thousands of watts, that would be needed."
Impressive efficiency, lasers do well to be 10% efficient so 100KW would be a decent baseline power. They should have said hundreds of thousands of watts.
Probably just bad editing but not a good sign about this article.
Seriously, a 16 mj railgun would work for close proximity, which is what is wanted on lasers.
I prefer the "u" in honour as it seems to be missing these days.
Let's call this what it is. Mirrors are a flat out stupid defensive response to laser weapons. They cannot work well enought under almost any conditions to justify spending any time on.
1). Perfect mirrors don't exist. Maybe inside a diamond, but even then your diamond must be perfect internally. Any battles fought inside a diamond, in all of human history?
2). Even in peacetime equipment gets dirty. Does your car get dirty? So how are you going to keep your military asset perfectly clean? Now do this under realistic battlefield conditions, with smoke, mud, dust, and bugs. Your mirror now ain't worth sh*t.
3). Ever notice how popular camoflage is on military equipment? So how exactly does a mirror surface reconcile with camoflage, when a mirror will reflect the sun or any other light source? It's like a neon sign advertising to the enemy, "Hey! Military equipment over here! Attack this point right here!!"
Defending equipment with mirrors is just plain stupid. Stop suggesting stupid defences.
Skepticism is an important part of gauging project goals, milestones, and progress.
NASA and the DoD would accomplish nothing of value without this crucial part of the scientific method.
The LLNL NIF lasers are currently chemical, but recent breakthroughs in solid state lasers are being evaluated in the Netherlands. Hopefully some truth data will come of it.
If only all of the President's cabinets were held to the same level of scrutiny.
Emit, yes. How fast do you think the projectile is moving after traveling 100 miles?
The projectile is deccelerating the entire 100 miles. It takes longer than 66 seconds.