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Factory Testing of Airborne Laser Cannon Completed
Acid-F1ux writes "Lockheed Martin has completed factory testing of the optical benches for the Airborne Laser's Beam Control/Fire Control (BC/FC) system. The Airborne Laser (ABL) is the first megawatt-class laser weapon system to be carried on a specially configured 747-400F aircraft, designed to autonomously detect, track and destroy hostile ballistic missiles."
It's a chemical laser. The fuel for the laser takes up a big chunk of that space.
The laser is invisible - off in the infrared somewhere. You could only probably see the beam at night as it ionizes the trace amounts of noble gases in the atmosphere. Then again, a bird or a swarm of beetles flying through the beam would be pretty spectacular. . .
Don't look at laser with remaining eye.
This sig is a test. If this had been an actual sig, you would be reading something quite a bit wittier than this now.
I imagine they would combine the laser with surveillance and detection functions such as AWACS or Joint STARS. In those cases it would not be such a strange idea to have one on CAP (Continuous Air Presence) over certain theatres of operation. But to defend all of the US with these would be a bit impractical.
Which leads to the question: what other stuff could they zap with this? Ground-based launchers? Enemy fighter aircraft? SAMs? Or is this thing only good against ballistic weapons?
If construction was anything like programming, an incorrectly fitted lock would bring down the entire building...
http://www.airbornelaser.com/
http://www.airbornelaser.com/
The offical project website with pics progress reports et al.
The ABL system is to be a key part of what is known as Boost Phase missile defense. The idea is that you fly the 747 based ABL system in circles over friendly territoy monitoring a neary balistic missile threat (imagine flying over Japan and watching North Korea). When an enemy ballistic missile is launched, the ABL uses its laser to blow-up the missile while it is climing through the atmosphere (having the advantages of being full of fuel, rising slowly and over enemy territory). See FAS for details.
I wonder what color the laser is...
I hear the green ones burn out your eye
Actually the laser beam will be invisible (unlike the the one in the movie Real Genius), as it is in the infrared range of light. This particular frequency of light also lends itself to good transmission through the atmosphere. More info here
Another interesting thing about the laser is that it's a chemical laser that genrates energy through the reaction of oxygen and iodine.
Which means that the plane will have a limited number of shots (I believe three or four) before it has to go and refuel.
The power of this laser would not heat up and pop the popcorn like in the movie, but would vaporize a nice hole right to the ground.
I hear the green ones burn out your eye
Looking into a laser or letting laser light into your eyes is a very bad idea, no matter how low the power may seem. Even for the pen lasers that are everywhere. You do not know what the consequences may be, and harm to your eyesight is not worth it.
Take the cheese to sickbay, the doctor should see it as soon as possible - B'Elanna Torres, "Learning Curve"
This depends on the reflectivity of the mirror. If it would be 99.999%, only some 10W would get absorbed by the missile. Un(?)fortunately, it is not possible to make mirrors with such a good reflectivity across all possible wavelengh. Especially in the IR range, it's quite difficult to make mirrors with >98% reflectivity. And I suppose the laser will be in the IR range.
Er, no. The beam exit is from a steerable turret on the nose of the aircraft, and can cover almost the entire hemisphere in front. Note the nifty animation on it's home page. ;-)
Also, it is not designed to destroy "inbound ICBMs", it is designed to go after boost phase missiles just after launch. They are easiest to see then, moving relatively slowly, under stress, can't launch decoys AND the debris (including warheads) falls on the launching party's territory. That's the theory anyhow...
Galileo: "The Earth revolves around the Sun!"
Score: -1 100% Flamebait
I call bullshit. Here's why.
Missiles are expensive. Missiles that can hit a target across thousands of miles are even more expensive. Those aren't expensive because they're costly to manufacture, they are expensive because they are costly to develop. Consequently any state that has ICBMs capable of striking the United States is likely to have a lot of them. Similarly the warhead on an ICBM is a fair bit more advanced than your rudimentary WOMD, largely because it has been miniaturized to allow it to fit in an area about the size of a four drawer filing cabinet.
If anyone is going to attack the US with missiles, they are going to do it with a lot of missiles, not a few that they purchased. It is easier to deploy a small number of warheads with stealth than with missiles. Large numbers of warheads require missiles.
So what is the system for then? If it can't knock down a large volley of missiles and we can't expect these "rogue nations" we keep hearing about to attack with ballistic missiles what is the system for?
The answer is simple really; it defends against a second strike. It is an order of magnitude more expensive to make weapons designed for second-strike capability: that is to say, weapons that will survive the first portion of a nuclear exchange. These second strike weapons are what creates the concept of deterrence. If China launches on us today, the nuclear subs and some of the hardened silos will survive, which will be enough to reduce China to a smoking crater. Thus China doesn't launch.
Now take this from the Chinese perspective. Much like the former Soviet Union, China's nuclear weapons follow a first strike doctrine. China's weapons are, for the most part, un-hardened, land based, fixed sites. The result is that China's nuclear doctrine is fixated on striking first (which is fairly destabilizing). If someone else strikes China first, China has very few missiles left with which to retaliate. And this system is designed to stop a very few missiles.
In other words, missile defense systems are now, and have always been designed to prevent the United States from suffering the consequences of escalating a conventional conflict to a nuclear one.
This in turn made a lot of sense in the cold war. Since nuclear deterrence is based on the infamous 3 Cs (Capability, Credibility, and Communication) and the ABM programs made our Credibility stronger (with these systems we were more likely to use nukes when we said we would) the ABM system would have made our bargaining position with the Soviets stronger.
However, today there is no Cold War. China has, for the most part, decided that we're not worth pissing off, and no other antagonistic force has a sufficient quantity of nuclear weapons to bother challenging the US in a conflict in which ballistic missiles are likely to be used. ABM today is little more than graft, and ill-conceived graft at that. The system makes the US less likely to consider the horrific consequences of using a nuclear weapon in a tactical situation (much like the proposals by the Bush administration to use nukes in the caves of Afghanistan).
In short, every argument you make above is incorrect. Aircraft mounted ABM is ineffective because you can only hit during launch, and that requires being over a country pissed enough to launch nuclear weapons at you. Proliferation of weapons of mass destruction does not imply the proliferation of the technology necessary to make those weapons strategically deployable. And 500 billion, while a bargain to save a city, won't do so because anyone with 20 or fewer weapons is far more likely to put a bomb on a boat and sail it to NYC than they are to put it on a missile at about a thousand times the price.
Finally, the deterrent factor doesn't exist. Until someone works out a way to eliminate (or hell, even FIND) Ohio class (or the soon to be deployed Virginia class) ballistic missile subs at sea, our deterrent is very, very, very safe.
ABM is a bad idea. It makes a nuclear exchange more likely, and that is bad for everyone.
Killfile(TGK)
No trees were killed in the creation of this post. However, many electrons were inconvenienced.
So, would a mirror coating on a missle be an effective counter measure to this laser?
.23 meters per minute through inch thick highly polished stainless steel.
That shouldn't be too difficult to do... heck, I was silvering mirrors in highschool chemistry class.
Well this laser is probably a COIL (chemical oxygen iodine laser), the military's favorite for laser weapons systems these days... COILs operate at a frequency of 1.315 micrometers... which is in the mid infrared band, for those that don't know... most mirrors (and substances) are opaque at this frequency; most of the light on this band is from blackbody radiation... here's an excellent primer on infrared transparency and absorbency...
You can make a dichroic mirror that reflects that wavelength, but the expense of coating a missle with it may be a couple orders of magnitude greater than the cost of the missle itself.
Here is a study of cutting different aerospace materials with a COIL. With a 6kW laser, they acheived a cut rate of
So if you added a mirror to a missile, and this laser is 1MW with comparable focusing capabilities as that used in the above study, assume that it's pulse duration is somewhere in the neighborhood of a tenth of a second, and that the missile is covered with quarter-inch thick stainless steel (unlikely due to weight), and that you have to cut through 10 centimeters of the missile before you affect it's circuitry enough to guarantee non-operation, your mirror would have to be 96.5% efficient in order to work. Mirrors in the near infrared band are typically 80% - 90% efficient using exotic glass chemistries and aluminum front surfaces... this mirror in the mid infrared band would have to be significantly more efficient with far more difficult manufacturing techniques...
I am disrespectful to dirt! Can you see that I am serious?!
I wonder what color the laser is...
I hear the green ones burn out your eyes.
It's already been said but let me repeat, any laser can burn out your eyes. Even low powered ones, when focused by the iris, can burn out portions of the retina.
This laser is infrared; that's actually WORSE than green. With a visible light laser, your eye sees the bright light and your pupil contracts to limit the exposure. With infrared, you can be in a pitch black room with pupil at full dilation and not even notice it. Until about six hours later when your vision slowly fades out.
I am disrespectful to dirt! Can you see that I am serious?!