Laser Weapon Shoots Down Airplanes In Test 627
airshowfan writes "Boeing's directed-energy weapons (a.k.a. frickin' laser beams) have been getting some attention lately. The Advanced Tactical Laser (ATL) is a C-130 that famously burned a hole through a car's hood, and the YAL-1 AirBorne Laser is a 747 that shoots a laser from its nose that is powerful enough to bring down an ICBM. But even cooler is the Mobile Active Targeting Resource for Integrated eXperiments (MATRIX), a laser that is mounted on a truck (which probably costs less than a 747, but who knows) and that can shoot down small aircraft, as shown in the picture on this article. (The Laser Avenger supposedly also has this capability). We live in the future!"
Shiny things? (Score:2, Interesting)
Wouldn't making your plane or missile shiny / reflective defeat these things pretty easily?
Re:Shiny things? (Score:1, Interesting)
Re:Shiny things? (Score:2, Interesting)
Radiation pressure?
Re:or we start treating it like a war (Score:3, Interesting)
What exactly did we have the stomach for then that we don't now? Nuclear bombs?
That and the whole idea of carpet bombing populated areas. While "WE" don't have the stomach for it, I hope our enemies are at least as civilized. I have little hope for our current crop of enemies, however.
Re:Shiny things? (Score:3, Interesting)
Homework assignment! To rip apart sheet metal, you'll need a pressure in the ballpark of 100 PSI.
Calculate the laser power needed to create this much radiation pressure with a 10-cm diameter beam.
Answer:
100 PSI = 69 N/cm^2
A = pi r^2 = 78 cm^2
F = P * A = 5400 N
F = dp/dt = 2 I/c
I = F c / 2 = 5400 * 3e8 / 2 = 800 GW
This amounts to 1/4 of total U.S. electricity consumption. Utterly impractical.
Deja vu (Score:3, Interesting)
This is a bit like gunpowder weapons in the 14th century. They appeared in Europe early in that century, were pretty pointless at first, then useful in special cases, then, after about 100 years, more-generally useful. Professional soldiers at that time must have been pretty skeptical. "Interesting, but I'll keep the trebuchet for now, thanks." Up to, say, 1350, it would have been difficult to predict whether gunpowder would ever become a practical weapon.
Re:Destruction is easy (Score:2, Interesting)
Re:Shiny things? (Score:3, Interesting)
A mirror on an ICBM needs to last maybe one blast, so it does need replacement nor cooling.
95% reflectivity seems to achievable relatively easily. A megawatt * 5% = less than it has to endure when going down, I'd assume.
Re:or we start treating it like a war (Score:1, Interesting)
There are some strong parallels between the US occupation of Iraq and the German occupation of Yugoslavia.
Re:Quick question (Score:5, Interesting)
To top it off, our invasion of Iraq totally screwed our operations in Afghanistan. So we did the absolute most ass backwards, ineffective thing we could have done, and now we are paying for it. Well, our young men and women are. Okay, not the sons and daughters of the people who sent us into Iraq, obviously, but, you know, our disposable young men and women are paying for it.
Makes you proud to be an American, doesn't it?
As a former soldier who went to the Middle East, I can tell you that I knew very well what our mission was and fully supported it. If I didn't, I would not have gone. I would have made a pass at the Platoon SGT or something to get my ass thrown out of the Army. When I was over there, I met the people I was there defending and understood why I was there. I was given freedom from my forefathers with help from the French. I didn't earn it. What makes me so damn special that I get freedom from tyranny and these people don't? I've earned it now. Sure, I didn't fight for my own freedom, but I gave the gift to someone else and would have been willing to die for it. I made that decision before I ever signed.
And yes! It makes me VERY proud to be an American, thank you.
We invaded Iraq. They had nothing to do with 9/11
Right. They violated 17 UN resolutions, tried to assassinate a former US president, fired at our soldiers who were there enforcing an UN mandate, and do I need to bring up the mass graves filled with men and women still clutching their toddler children?
Afghanistan may have been their home base, but if we invade countries because they house terrorists, who should we have invaded because of Tim McVeigh?
Housing terrorists is one thing. Terrorists live everywhere. It's when the government knows they are there and do nothing about it. The Taliban didn't just "house" Al Qaeda , they harbored them. They actively assisted them and refused our offer to take care of them ourselves. What would you have Bush do? "Hello, Mr. Taliban guy, Dubya here. Listen, the guys that planned the attack that killed 3000 of our citizens are in your country. Do you mind if we come get them? I'm sorry, what was that? No way in Hell? What about my mother? Well, OK then. Thank you for your time. (hangs up phone). Sorry, Dick, they said no."
Re:Shiny things? (Score:2, Interesting)
Re:So, which future is it? (Score:2, Interesting)
Re:Shiny things? (Score:4, Interesting)
Well it really depends on the the power density in the beam. If a target is 90% reflective to the the wavelength used by the laser, then the laser would have to be 10 times more powerful to achieve the same heating in the target. My guess is that polished aluminum might maintain 90% reflectivity, but who knows. Of course, a speck of highly absorbing dust will burn very quickly, subsequently, the burned area around the dust will also begin absorbing so a hole may grow very quickly. The question is then: how long can the laser remain focused on the burning patch? If it wanders due to atmospheric disturbance the spot may not cause a failure of the target.
Here's the real problem. If you make the laser so powerful that a bit of dust will cause a significant burn to start, a speck of dust on your targeting optics will obliterate the laser platform itself. You could manage this by using a very large targeting mirror and focusing onto the target (possibly what the system does but I couldn't be bothered to look it up) but then you need accurate range-finding as well as directing and you need to keep the beam targeted precisely enough to hit a small focal point for an extended (probably still less than a second) period of time .
At the end of the day the whole system is damn hard to get working. Targeting an enemy missile rather than a slow-moving drone may still be an unsurmountable challenge. I suspect that the whole system is a giant waste of money made even more expensive by the possibility of shiny targets.
Re:Shiny things? (Score:3, Interesting)
Well, we are talking about the properties of mirrors being exposed to high energy lasers. What research are you referring to by the way? Any links?
Yes, you keep saying that. Do you expect people to take your word for it (especially considering you admit to not being an expert)?
Sure, but all this is meaningless without numbers. How rapidly? How long is the laser pulse?
Re:Shiny things? (Score:3, Interesting)
If a cannon (of any technology) dumps it's energy near you, you die. It doesn' much matter whether the laser cannon heats the skin of the missile, or the air next to it, to plasma temperatures, it's enough to destroy the missile. These weapons are not intended to be energy efficient, they're intended to reach a fast-moving target quickly. For example, an ICBM boosting to orbit is a clear and obvious target, but you can't catch it with a missile - it's already the fastest missile there is. But you can easily tag it with a laser.
What are we even fighting for? (Score:3, Interesting)
You don't fight fair -- you fight to win. We used to understand that. Our enemies still do.
And what exactly is a "win" in the context of afghanistan? We need to make sure that whatever we do to "win," whatever that even is in this context, doesn't create more enemies.
Re:How to pull this off (Score:1, Interesting)
The Airborne Laser isn't a waste of money - it's great!
The modern nuclear triad, submarines, ICBMs and airborne delivery are still what our opponents use.
The briefcase bomb, nuclear artillery shell, and nuclear cruise missile are other delivery systems that could be used too.
The Airborne Laser would be very effective against ICBMs in a boost phase.
It is ideal against North Korea and Iran should they choose to use a SCUD-like missile with a nuclear warhead.
It's pretty useless against ICBMs in orbit or coming down.
It's useless against all of the other delivery systems.
But for what it's good at, it's great!
Well worth the money, it's wonderful!
Please don't cancel this program.