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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)."
You're being too literal. It could be used for anti-missile defense.
The article says kilowatts.
32 kW, not MW, thats kilowatt, not megawatt.
There are numerous advantages to using lasers instead of traditional weapons:
*) Longer range
*) Better accuracy
*) Unlimited ammunition
*) No pollution from spent weapons
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?"
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
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 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.
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.
So - we should just give the money to the people without jobs?
Only if you want a line millions of people long once they hear you are handing out free money. No, I think the point is the government shouldn't have the money in the first place. Perhaps if the people who create the jobs had a little more money (in the form of paying a little less taxes), they'd be able to create more jobs.
But then again what do I care. It's not as if I pay income tax anyway. Thank god I'm not a US citizen - no matter where you guys live you have to pay for crap like this, it's the law.
Seven puppies were harmed during the making of this post.
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.
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 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.