Hard Light Productions Forums
Off-Topic Discussion => General Discussion => Topic started by: Ghostavo on March 24, 2009, 05:53:50 am
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Northrop Grumman Scales New Heights in Electric Laser Power, Achieves 100 Kilowatts From a Solid-State Laser (http://www.irconnect.com/noc/press/pages/news_releases.html?d=161575)
REDONDO BEACH, Calif., March 18, 2009 (GLOBE NEWSWIRE) -- Reaching new heights with its scalable building block approach for compact, electric laser weapons, Northrop Grumman Corporation (NYSE:NOC) has produced the most powerful light ray yet created by an electric laser, measured at more than 105 kilowatts (kW).
A photo accompanying this release is available at http://media.globenewswire.com/noc/
The company claimed ownership of this record by completing the final demonstration milestone of the U.S. military's Joint High Power Solid State Laser (JHPSSL) program, Phase 3. The achievements included turn-on time of less than one second and continuous operating time of five minutes, with very good efficiency and beam quality. Last year, Northrop Grumman reported reaching a JHPSSL Phase 3 power level of 15.3kW in March and a power level of 30kW in September.
"Our modular JHPSSL design makes it straightforward to scale laser weapon systems to mission-required power levels for a variety of uses, to include force protection and precision strike missions for air-, sea- and land-based platforms," said Dan Wildt, vice president of Directed Energy Systems for Northrop Grumman's Aerospace Systems sector.
"This achievement is particularly important because the 100kW threshold has been viewed traditionally as a proof of principle for 'weapons grade' power levels for high-energy lasers. In fact, many militarily useful effects can be achieved by laser weapons of 25kW or 50 kW, provided this energy is transmitted with good beam quality, as our system does. With this milestone, we have far exceeded those needs."
Wildt continued, "Power scaling will be one of the game-changing features of high-energy lasers because it allows graduated responses by U.S. military services appropriate for whatever level of threat they may face. Threats vary, and so should the response."
Jay Marmo, Northrop Grumman's JHPSSL program manager, pointed out how the company's scalable, building block approach also readily enables more challenging missions that require well above 100 kW of good beam quality laser power.
"Getting to 100 kW with replicated building blocks proves we can scale to these higher power levels if required for a given mission. This watershed development, coupled with our FIRESTRIKE(tm) laser ruggedization work, unequivocally demonstrates that Northrop Grumman is ready to bring high-power, solid state lasers to the defense of our deployed forces."
For building blocks, the company utilizes "laser amplifier chains," each producing approximately15kW of power in a high-quality beam. Seven laser chains were combined to produce a single beam of 105.5 kW. The seven-chain JHPSSL laser demonstrator ran for more than five minutes, achieved electro-optical efficiency of 19.3 percent, reaching full power in less than 0.6 seconds, all with beam quality of better than 3.0.
The laser already has been operated at above 100kW for a total duration of more than 85 minutes. A government team reviewed results of the demonstration during a System Test Data Review held Feb. 10 at Northrop Grumman's Directed Energy Production Facility in Redondo Beach, Calif.
"It is notable that we were able to meet the power demonstration goal with only seven laser chains, rather than the full eight chains we can accommodate. This shows the robustness of our industry-unique approach and the ability of our lasers to deliver predicted performance," Marmo emphasized. "Adding the eighth chain will increase laser power to 120kW."
Now we can kill each other more efficiently!
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w00t
Don't they already use something like this for crowd control?
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What effect does 103kW of laser beam have on:
People?
Metal?
Buildings?
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For building blocks, the company utilizes "laser amplifier chains," each producing approximately15kW of power in a high-quality beam. Seven laser chains were combined to produce a single beam of 105.5 kW. The seven-chain JHPSSL laser demonstrator ran for more than five minutes, achieved electro-optical efficiency of 19.3 percent, reaching full power in less than 0.6 seconds, all with beam quality of better than 3.0.
Oh hell yes. Death star! :D
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Get me a 1.21 GW laser and we're talking... ;7
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About time too. Now, aren't we supposed to be piloting Mecha by now ? :p
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What effect does 103kW of laser beam have on:
People?
Metal?
Buildings?
Something cooooooooooooool
*Dilmah drools on keyboard, visualising some kind of beam cannon sitting on his lawn*
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Hoo boy, yet another step forward for beam tech. :rolleyes:
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http://en.wikipedia.org/wiki/Laser#Examples_by_power
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Now we can have sharks with frickin' laser beams attached to their heads! :drevil:
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i got to watch a laser surgery be performed when i was a kid, the light came on and the blood started flowing. it was sorta cool. from the table on wikipedia that was probibly just a 100 watt laser.
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Maybe I missed it but the article doesn't seem to mention anything about what wavelength laser this is. :/ I'm betting it's infrared like those used for industrial cutting but it'd be awesome if it were visible light.
What effect does 103kW of laser beam have on:
People?
Metal?
Buildings?
A 1kW infrared laser cuts through 1-inch thick steel like a hot knife through butter, so scale that up by about 100 times and imagine it hitting something. Buildings probably not too much but a person would be sliced through pretty much instantly. This would also depend on the size of the beam (smaller cuts better) and also wavelength light the laser emits.
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I'm pretty sure I have a magazine of optics that talked about this couple of months ago. They had it in a airplane, ready to pulverize buildings. This should actually decrease the collateral damage, since there is no blast radius. Though I wouldn't like to get one scattered beam towards eyes.
The cutting power of a 1000 W (if this is the actual OPTICAL power) industrial level laser depends on the total amount of energy emitted and the spot size on the target, with linear dependency in the power and inversely quadratic dependency on spot size.
1 kW of optical power over somebody's frontal area (~2 m * ~0.5 m) = 1m^2
1 kW / 1m^2 = 1000 W/m^2, approximately the irradiance caused by sun. While this isn't dangerous level to human, the collimated beam can still cause problems to eyes.
Putting there 100 kW is another case, but there is not enough information to tell the minimum spot size on the target. Putting that energy to a diffraction limited spot of 5 µm is then again one...
One of my colleagues once mentioned focusing a slightly more powerful laser to a dust particle. The bang was audible to give you an idea...
Mika
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http://en.wikipedia.org/wiki/Laser#Examples_by_power
On March 18, 2009 Northrop Grumman announced that its engineers in Redondo Beach had successfully built and tested an electric laser capable of producing a 100-kilowatt ray of light, powerful enough to destroy an airplane or a tank. An electric laser is theoretically capable, according to Brian Strickland, manager for the United States Army's Joint High Power Solid State Laser program, of being mounted in an aircraft, ship, or vehicle because it requires much less space for its supporting equipment than a chemical laser.
So now we have saaa#weak#weak beams? Surely in 300 years, they will have something better than a BFGreen, considering the rate of advancement of technology (unless humans war themselves back to a more primitive state).
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You forget, a BFGreen is measured in terrawatts or more probably. A tank is fairly impressive, of course, but FS fighters withstand kiloton-yield blasts with ease. :P
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You forget, a BFGreen is measured in terrawatts or more probably. A tank is fairly impressive, of course, but FS fighters withstand kiloton-yield blasts with ease. :P
:wtf: kind of difficulty do you play on? :p
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:wtf: kind of difficulty do you play on? :p
The one were I read the techroom. The Fury has a canonical yield of 3Kt. (http://www.hard-light.net/wiki/index.php/Fury) The MX-50 is 16.5 Kt. (http://www.hard-light.net/wiki/index.php/MX-50)
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Maybe I missed it but the article doesn't seem to mention anything about what wavelength laser this is. :/ I'm betting it's infrared like those used for industrial cutting but it'd be awesome if it were visible light.
What effect does 103kW of laser beam have on:
People?
Metal?
Buildings?
A 1kW infrared laser cuts through 1-inch thick steel like a hot knife through butter, so scale that up by about 100 times and imagine it hitting something. Buildings probably not too much but a person would be sliced through pretty much instantly. This would also depend on the size of the beam (smaller cuts better) and also wavelength light the laser emits.
If you pump enough energy into a small enough space of matter, instead melting it will vaporize - explosively.
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So we just need an auto-lens and we will have lasers that work like a continuous row of TNT exploding on the target? Nice :yes: .
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The problem when dealing with continuous wave lasers is once the laser hits the target, vaporized material will block/deflect the beam and lessen its effectiveness. But maybe moving the laser across the target like a terran slash beam could overcome that. ;)
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thers where pulsed beams come into play.
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I'm not a physicist, so.... How effective would reflective armor be against something like this?
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I'm not a physicist, so.... How effective would reflective armor be against something like this?
Marginally effective. Any reflective surface still absorbs enough of the energy that it's surface would sublimate or vaporize almost instantly, lose it's reflectivity and then it would not be very effective any more.
Water ice layer would be a lot more effective since it takes a lot of energy to phase shift it into non-solid form. Even more effecive could be a circulated water layer where the absorbed energy is rapidly dispersed.
However, if the laser is powerful enough to instantaneously vaporize water and bore through the layer of ice or water, this kind of armour could turn agaisnt it's user since water vapour would end up expanding rather rapidly and violently...
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The problem when dealing with continuous wave lasers is once the laser hits the target, vaporized material will block/deflect the beam and lessen its effectiveness. But maybe moving the laser across the target like a terran slash beam could overcome that. ;)
That's one of the problems weapon designers still have to overcome.
However the phenomenon maybe used in a nasty application - if you can match the lasing frequency of the expanding ball of debris gas, you can use it as another lasing cavity. Needless to say with messy results on the receiving end.
As usual Project Rho has all the answers mapped out a long time ago:
http://www.projectrho.com/rocket/rocket3l.html
http://www.projectrho.com/rocket/rocket3x.html
http://panoptesv.com/SciFi/DeathRay.html
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Water ice layer would be a lot more effective since it takes a lot of energy to phase shift it into non-solid form.
Yeah, but only by kJ at a time, hardly worth even spending the effort on. Even factoring in instant conversion from solid to gas we're only talking somewhere around 2260 kJ total energy required to vaporize from solid state. A 100 kW laser emits energy equivalent to 360 megajoules. It would take about 0.0063 seconds to burn right through it, with a net energy loss of ~0.625 kW. Behind that laser would still be about 357740 kJ of energy ready to rip something open.
EDIT: Had to fix a couple math mistakes
NOTE: This is taking into account ice that is 1 cm thick, and a laser that is focused at a 1 cm point of contact.
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I wouldn't bet that the spot diameter is below 1 cm. I would find it surprising if it was, due to a couple of fundamental properties of light. I project a sudden interest in the development of cheap reflective diffractive elements.
Scotty, could you explain reasoning behind of released energy of 360 MJ?
I think that the energy [J] released equals power [W=J/ s] times the time unit [ s ]. Now, using 360 MJ = 100 kW * t and solving for t gives
t = (360*10^6 J) / (100 * 10^3 J/s) = 3.6 * 10^3 s = 3600 s. Somehow I suspect that illumination time is less than one hour...
Mika
EDIT: Had to modify [ s ], the forum will interprete it as strikethrough otherwise.
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It will also be interesting to see how quickly lasers are taken into use as airplane destruction devices. I would suspect that ground based laser systems that have high enough power levels to destroy aircrafts would drastically reduce the effectiveness of air forces. Surprisingly, the aircraft is actually a sitting duck in situation like that because a ground based laser is difficult to detect until it is too late. And it takes only a couple of seconds of lasing to knock off an airplane, and it can all be done visually point-and-click wise. No radar is required to engage the target.
Interesting times indeed.
Mika
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Ah, you would be correct. I was using a google converter and forgot to change from kW/hrs to seconds.
That of course makes it an order of magnitude more effective, but I still think that using some sort of high melting point metal would be more effective in deflecting energy from the target.
@second post:
It would have the effect of being unavoidable if targeted by computer. If the 'projectile' is traveling at the speed of light, there is no maneuvering time whatsoever.
I'll get the math ready to find out how long it would take to shoot one down, provided 100 kW laser and aluminum plane.
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Finally got the math:
24.2 J/mol · k (298 k)
Melting point: 933.47 k (660.32°C)
Boiling point: 2792 k (2519°C)
Specific Heat: 0.89 J/g·C
Heat of Fusion: 10.790 kJ/mol
Heat of Vaporization: 293.40 kJ/mol
Density: 2.702 g/cm3
Atomic Weight: 26.98153858
Heat = mass x CpAl x temperature change = heat capacity x temperature change
MiG-29
Height: 4.73 meters
Wing Thickness: 39.4178 centimeters
Length: 17.37 meters
Wing Length: 4.75 meters
Total Volume of 1cm strip of wing at fuselage: 1872345500 cm3 » 1.87 m3
Total Volume of 1cm2 strip of wing: 39.4178 cm2
106.5068956 g in 1cm2
3.947398896 mol in 1 cm2
106.5068956 g ·0.89J/g·C · 660.32 C = 62592.48364 J
3.947398896 mol · 10.790 kJ/mol = 42.59243409 kJ
Total energy required to melt a 1cm2 patch of wing: 105.1849225 kJ
Using 103 kW laser » 103 kJ/second energy output
Now just multiply that by the remaining 4750 centimeters in that wing. Total energy required is (105.1849226 kJ x 4750 =) 499628.3817 kJ. It would take nearly 500 mega joules of energy to take down the plane. It will take 1.02121284 seconds to melt (just melt, not vaporize) just one patch, and will (would) take a little over 1.34 hours (1 hour, 20 minutes, 50.76 seconds) to melt completely through the wing. Granted, the plane would not be in the air with a half-melted wing, it would still take considerable time to render a plane unfit to fly.
EDIT: holy crap did I mess that one up. For some reason I thought it was 1000 cm to a meter. The time should be about 8 minutes, not over an hour.
Still too long to be effective.
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Yes but it would definitely get the MiG to piss off
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I was thinking the water as ablative shielding would be far more effective on heavy vehicles or space ships rather than airplanes, since what I have in mind does require somewhat more thickness and mass on the shield system to increase it's thermal capacity.
By the way what happens with liquid water when you point a laser on it? Especially if the water is not still but kept in circulation. I'm thinking of a setup with outer shell and inner armour, with a layer of water in between. Ice would be problematic not only because it's solid and requires active cooling in most cases but also because of the expansive behaviour when it actually freezes. With liquid water plus de-ice chemicals you could still cool it below zero degrees Celcius, too.
How much energy would the water absorb as the laser passed through the outer shell and started to penetrate the water layer? Water is after all reasonably transparent, and would likely let most of the light travel through itself, so it's not like you can just focus all that energy on the surface of the water.
Second important thing is that water is what happens to the inner armor layer when the laser touches it. Mainly I'm interested in how much conduction and convection of thermal energy happens near the heating spot. Convection of course depends partly on how much the water circulates, but even on still water there would still be gravity-induced convection to some extent.
And what happens when you change the water into suspension by inducing some particles that very effecively diffuse any light?
Of course there are problems when the laser becomes powerful enough to focus enough energy on surface of the water to start immediately vaporizing it, in which case the rapidly expanding vapor will cause a steam explosion and a shockwave that first ruptures the outer shell of the armour configuration and then it would be a case of "Goodbye, Mr. Bond".
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Now America can kill others more efficiently!
fixed it for you.
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Water is after all reasonably transparent, and would likely let most of the light travel through itself, so it's not like you can just focus all that energy on the surface of the water.
This interestingly enough would be one of the major flaws. Not only would it let most of the energy through, providing negligible resistance, it would also magnify the intensity of the beam.
With respect to armor, the best materials that would be practical are either sodium, beryllium, or magnesium. Magnesium is out for obvious reasons (tends to catch fire easily). Sodium reacts violently with water, so wouldn't be effective anywhere there is even more than a little water (read: anywhere but a desert). Beryllium has an enourmous specific heat (the amount of energy required to heat one gram of that substance by one degree celsius or kelvin, in this case 1.83 J/gxC) and also a very high melting point (around 1278 degrees celsius). It is non-magnetic, and is also very light-weight. It is also very corrosion resistant, so it would only have to be replaced after direct combat damage. The greatest downside to it is that it is relatively rare.
The next best thing would be aluminum (0.91 J/gxC), but we've already gone through how that would do in my previous post.
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you really dont have to cut the wing iff, just pierce into the fuel tank. most planes put the tanks in the wings, easy to hit and a fuel explosion is enough to take the wing out. i doubt it would explode at first. youd probibly get a small fuel leak which will immediately ignite, however it would be much like a tiny flame, due to little oxygen at altitude and the cooling effects of wind over metal. localized metal vapor may mix with the fuel and cause an initial flareup. worst (or best if youre the gunner) case scenario is an internal fire. not sure how fast a laser will heat the fuel but pressure expansion may rupture the tank which would be extreamly hazardous with an internal fire raging. targeting specific parts of the plane, for example turbines, avionics, fuel lines to the engine, explosives in ordinance, the pilots head, ect may cause a more rapid failure of the aircraft.
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Water is after all reasonably transparent, and would likely let most of the light travel through itself, so it's not like you can just focus all that energy on the surface of the water.
This interestingly enough would be one of the major flaws. Not only would it let most of the energy through, providing negligible resistance, it would also magnify the intensity of the beam.
How would it do that? It would absorb some of the energy (how much would be adjustable by suspension concentration). Even if there were some sort of lens effect in play, lasers aren't really that easily focused since they are already coherent beams of light. Moreover the water would cause scattering and dispersion of the beam like any substance that radiation passes through. and it definitely doesn't magically add power to the beam... :nervous:
The most important effect though would be how much of the heating power could the water conduct or transfer away from the point where the laser hits the inner surface under the water layer. If the water layer is able to absorb and disperse the beam enough, it might be weak enough not to be able to heat the inner surface enough to melt or vaporize it, especially when the water is there cooling the surface.
With respect to armor, the best materials that would be practical are either sodium, beryllium, or magnesium. Magnesium is out for obvious reasons (tends to catch fire easily). Sodium reacts violently with water, so wouldn't be effective anywhere there is even more than a little water (read: anywhere but a desert). Beryllium has an enourmous specific heat (the amount of energy required to heat one gram of that substance by one degree celsius or kelvin, in this case 1.83 J/gxC) and also a very high melting point (around 1278 degrees celsius). It is non-magnetic, and is also very light-weight. It is also very corrosion resistant, so it would only have to be replaced after direct combat damage. The greatest downside to it is that it is relatively rare.
Not to mention beryllium is pretty darn harmful (http://en.wikipedia.org/wiki/Beryllium#Precautions) (I think even more than asbestos or depleted uranium).
The next best thing would be aluminum (0.91 J/gxC), but we've already gone through how that would do in my previous post.
Well, in terms of volumetric heat capacity (http://en.wikipedia.org/wiki/Volumetric_heat_capacity) water is number one, which defines the physical dimensions (or thickness) of the layer you need against the laser. Water also has very very high specific heat, so even though it melts and boils at lower temperature than beryllium, it would still likely be more useful for space ship armour... as it can also be used as a heat sink and water supply as well as food supply (you can grow algae in some sections).
Certainly, beryllium has high melting point but it's also a lot less practical than building a lightweight dual-layered structure and filling it with water, and putting critical components within the water layer protection The inner and outer surface materials should obviously be something solid, but as far as
Obviously stuff like sensors, thrusters and weaponry that needs to be on the outside would still be vulnerable but structural integrity of manned sections would be protected along with life support and reactors and other critical components.
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Oh. You were talking about space ships. I was talking about stuff like tanks.
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Oh. You were talking about space ships. I was talking about stuff like tanks.
Well it would still be somewhat applicable to tanks. More so than on airplanes anyway. The physical size of the tank would limit the usefulness of such armour though.
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Hence why I was talking about metals and not anything else.
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I think I need to go through some of those calculations first. My guts tell me something is missing in there. More about it on "not today".
When talking about aircrafts, a small cut is enough to cause significant deviations in the airflow.
Mika
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If we're talking about computer-targeting, couldn't you just 'clip' something important?
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When talking about aircrafts, a small cut is enough to cause significant deviations in the airflow.
Hmm, has a bit of merit there. I posted every single number I used in my calculations in the post, feel free to go over and see if I missed something. The only problem is that if you miss by even a little bit, and only blow a little hole and not cut the edge, it keeps flying. Aircraft remain airworth even if struck with bullets, so lasers may still have some work to do.
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Honestly, how much can a laser do that bullets, missiles and the like can't do more efficiently?
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Not be affected by air-currents?
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Travel at the speed of LIGHT?
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Look freaking cool?
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But its expensive to develop and deploy, bulky, impractical, and there are usually cheap alternatives . . .
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But its expensive to develop and deploy, bulky, impractical, and there are usually cheap alternatives . . .
Fair enough
but if you really wanted something dead with 100% Accuracy....
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But its expensive to develop and deploy, bulky, impractical, and there are usually cheap alternatives . . .
:wtf:
Look freaking cool?
:P
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When talking about aircrafts, a small cut is enough to cause significant deviations in the airflow.
Hmm, has a bit of merit there. I posted every single number I used in my calculations in the post, feel free to go over and see if I missed something. The only problem is that if you miss by even a little bit, and only blow a little hole and not cut the edge, it keeps flying. Aircraft remain airworth even if struck with bullets, so lasers may still have some work to do.
Scotty I believe you're off in your estimates...
...and it's not a miscalculation per-se, but the physical model you use for the damage mechanics involved.
Even lower powered (nowhere near 100kW) lasers were able to cook-off grenades and other combustibles/explosives in a couple of seconds.
Here is how others calculated:
http://panoptesv.com/SciFi/DamageAverage.html
Using his calculator we get this data:
Damage to Aluminum
Beam parameters
Beam power: 100000 W
Beam diameter at target: 0.01 m
Material properties
density: 2700 kg/m3
Heat of fusion: 0.397 MJ/kg
Heat of vaporization: 10.897 MJ/kg
Heat capacity: 0.897 kJ/(kg K)
Melting temperature: 933.47 K
Boiling temperature: 2792 K
Ambient temperature: 296.15 K
Material damage
Black body temperature: 12240 K
Rate of vaporization: 2.737E-06 m3/s
Vaporization front propagates at: 0.0348 m/s
The crucial date is the last entry 0.0348 m/s - this is the "drilling speed":
3.48 cm/s - that's one very fast drill. The wings of the plane are rarely that thick, so most hits *will* penetrate *into* the plane and damage internal structure and equipment. Doing it with even a single engines will be a *mission kill*, for all intents and purposes.
Drilling into explosives - the bombs or the missiles - will also rob the plane of its purpose as it will be no longer be able to perform air superiority or bombing missions.
Even better, with this thing you could shoot down the weapons even as they fall/fly toward you.
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Truth is, a modern aircraft is extremely vunerable to damage when moving at high speeds; that's why when damaged their first action is usually to slow down. At supersonic speeds a few 20mm holes in the airframe, even without the explosive power of the round, will cause most aircraft to rip themselves apart. Parasitic drag is a harsh mistress.
As for armoring goes, water and the like strikes me as a nonstarter. The obvious answer is the same one developed to deal with HEAT-type (which isn't just a convenient monikor) penetrators: ceramics.
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Honestly, how much can a laser do that bullets, missiles and the like can't do more efficiently?
But its expensive to develop and deploy, bulky, impractical, and there are usually cheap alternatives . . .
Several reasons. I think point and click ability would interest anyone in the field of AAA and SAMs plus that there will be no advance warning until something is actually broken, by that time it is already too late. There is not even need to use active homing devices as passive aiming systems would work fine at that range. And it would be deviously difficult to dodge the beam. Considering the time frame, there is pretty much nothing that could be done to avoid getting blasted.
Also, considering the laser is bulky, but I think the systems it would replace are actually a lot more bulkier and heavier (think radar, missile launcher and AAA, they all are generally tracked vehicles!). The cheap alternatives don't have the same hit percentage, and these will actually reveal the location of the shooter. Yes it is probably more expensive, but is the price worth the cost? The carrot is that even a stealth fighter cannot avoid getting blasted by one. Finding one laser battery would actually be quite difficult!
Mika
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So if a BFGreen is 103 terawatts, radius 30m and is fired at pure iron/steel, then:
Damage to Iron/Steel
Beam parameters
Beam power: 1.03E+14 W
Beam diameter at target: 60 m
Material properties
density: 7874 kg/m3
Heat of fusion: 0.247 MJ/kg
Heat of vaporization: 6.088 MJ/kg
Heat capacity: 0.449 kJ/(kg K)
Melting temperature: 1811 K
Boiling temperature: 3134 K
Ambient temperature: 300.15 K
Material damage
Black body temperature: 28310 K
Rate of vaporization: 1719 m3/s
Vaporization front propagates at: 0.608 m/s
Does this seem appropriate? At 700 TW, Vfp's at 4.13/ms.