Posted by
michael
on from the also-useful-for-making-popcorn dept.
KeyShark writes: "An article on FoxNews describes how front-line troops soon will be protected by battlefield lasers designed to shoot down rockets, artillery shells and even mortars."
Sounds like they put a fire-finder radar tracking station onto a laser. They've had the ability to plot trajectory and such of incoming shells for quite a while, but now they'll be able to do something about it other than leave.
Unfortunately, I have suspicions if this will ever make it to deployment. The U.S. also has an anti-satellite laser weapon that has been tested and confirmed to work by overloading the circuits -- and it was nixed because of the poltical tension it would create.
are artillery shells that delicate?
by
rebelcool
·
· Score: 3, Interesting
I know the airborne laser (uses the same chemical type laser) was capable of shooting down rockets by weakening the metal skins, which the forces of flight would thus rupture and cause the thing to fly apart, but are artillery shells really that delicate?
--
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Re:are artillery shells that delicate?
by
pryan
·
· Score: 3, Interesting
For artillery shells without an explosive payload, I would imagine if you could melt the tip, it would throw off the aerodynamics to throw the shell off course. That is assuming, of course, that you didn't vaporize it.
And for ones with an explosive payload, the obvious would happen in flight.:)
This raises some frightening questions
by
joshjs
·
· Score: 4, Interesting
What's to stop them from using these things on people? They have amazingly accurate targeting systems and they're cheap to fire (article says 25 cents (maybe dollars, I forget...) per shot.
So what's to keep the defense dept. from using these things for assassinations, or ground warfare?
Would that be cruel and unusual?
Here's a question: is there a "right of the people" to keep and bear these? The idea doesn't sound assuring, I must say: what kind of signature would it leave. Bullets can be tracked, but this -- would there even be a body left?
I'm not trying to complain or predict horrors, because I'm all about the advance of tech. I just want to know a little more about this kind of thing.
Also: it's eerie that the article only mentions uses of these for defense, and not for attack, covert (which I think is a promising potential use for this technology) or otherwise. Just considering it's a time of "war" and all.
Re:This raises some frightening questions
by
Anonymous+DWord
·
· Score: 3, Interesting
Here's a six year old report on blinding weapons of the US military.
-- "If he thinks he can hide and run from the United States and our allies, he's sorely mistaken." Bush on bin Laden
More handy links
by
mbessey
·
· Score: 4, Interesting
Most of these haven't been updated in a while, though...
Throw ball bearings very, very fast
by
leonbrooks
·
· Score: 3, Interesting
A standard truck-mounted generator with a couple of little railguns on the roof would do the same job (by flinging a bucketful of ballbearings at the target in a second or so) for a lot less $$$ and would also make a really neat ripping noise when it fired.
Not as easy to steer as a laser but extremely difficult to defend against. Good for anti-aircraft as well, since colanders have poor aerodynamics. Anything not detonated by ball bearings doing many kilometers a second would be thrown well off course. Not that this is not necessarily an advantage, since certain nations are reknowned for just carpeting the target area with ordinance and knocking something off course might make it more accurate.
Re:Also under development:
by
Nindalf
·
· Score: 4, Interesting
Mirror coating, etc. doesn't make a difference.
To be blunt, this is wrong. I do agree, however, that just polishing up a stainless steel shell until you can shave in front of it probably won't make enough difference. Most mirrors don't reflect nearly enough light.
On the other hand, such powerful lasers are hard to make and very expensive. It would be tempting to make them just barely strong enough to work against existing designs which have no defense against such countermeasures. If a spinning (or randomly tumbling), mirrored shell, can cut down the rate of heating by something like 30%, and there's some extra heat-shielding inside, it might be enough to survive.
All kidding aside, you also can't rule out, as I said, revolutionary new developments in mirrored armor. I mean, if there was no way to deflect the beam, there would be no way to generate or aim it!
BTW, Tom Clancy is a novelist, not a physicist. His entire livelihood is sounding plausible about things he doesn't really understand.
Besides, in the battle between bigger armor and bigger guns, the guns always win eventually.
Ah, but which is which? This is an odd historical precedent to apply in favor of a defense mechanism.
Is anyone else wondering.....?
by
moonboy
·
· Score: 3, Interesting
Is anyone else wondering why we are spending so much money on the missile defense system? This seems to have solved the problem of missile defense much more elegantly (and more cost effectively?) Maybe I'm missing something.
Weapons treaties are there to be ignored by a the parties signing them.
THink of it, you sign a treat to (say) not research biological weapons for offensive purposes, say, like Russia did. Then, you secretly violate the treaty, and now you have weapon the other side doesn't have. Its happened in the past, it'll happen in the future.
Weapons treaties only penalize the honest countries. Dishonest countries won't care. At least we actually do (for the most part) obey our treaties.
There's LOTS of stuff you can burn...
by
Ungrounded+Lightning
·
· Score: 5, Interesting
"These lasers also have a drawback--their energy comes from large tanks of industrial chemicals, which have to be mixed until they glow, like an outsize high-school science project. And they are so bulky that one weapon fills a large aircraft, or a small building. "
Does this jive with the fox news article?
Yes. But it doesn't tell the whole story.
The lasers they're talking about are spinoffs of the Star Wars missile defense system. They had to get a LOT of energy into a beam quickly, to shoot down missiles while still in space, or to bounce off a mirror in space to get them on their way up. One shot, one dead nuke, so cost wasn't much of an object.
Neither was portability: You had either a fortified underground bunker as big as you wanted, or a satellite in zero-G.
So they did something very strong, effective, big, and expensive.
But lasers are EASY. Excluding superradiants (which are easier, if you've got the materials) all you need is a couple of well-alligned mirrors, one of 'em slightly leaky, with an "inverted population amplification light amplification medium" between them.
For "inverted population light amplification medium" read "smoke from a fire".
The medium must have the following characteristics:
It has a state transistion (an "excited state", a "ground state" or less-excited state, and an allowed transition between them) with an energy difference corresponding to a usefully energetic photon.
It must have significantly more of its atoms or molecules in the more-excited state than in the less-excited state. (This is the "inverted population" part.)
It must have ENOUGH of a surplus of more-excited particles to produce a usable amount of power if you extracted the energy difference by de-exciting enough that you're down to 50/50 (or de-exciting them all if there's a further transition that drains the less-excited state).
It must be transparent and reasonably uniform (i.e. non-distorting) at the light frequency corresponding to the state transition.
When you burn darn near ANYTHING the resulting molecules start out excited. If they meet the other criteria you've got a suitable medium for a chemically-pumped laser.
Burn a suitable fuel in a long, thin, rocket flame and run the exhaust at right angles between the pair of mirrors. You'll have a laser beam coming out as long as the flame lasts. Chose the right material and a large fraction of what would have been the heat of combustion ends up in the laser beam.
Now there are some fancy and deadly fuels (fluorine comes to mind) that make an exhaust where the bulk of the energy can be extracted by a single transition. This is nice and efficient. And you don't want to be ANYWHERE NEAR them when in use, due to the toxic nature of the exhaust. So if you're going to be shooting down a nuke from a fort in the desert they're fine.
But there are LOTS of others that are simpler, and might be more suitable for a battlefield.
I expect that eventually we'll see a chemically-pumped laser rifle or pistol, about the same size as a normal rifle or pistol, with an optical cavity where the barrel would be, powered by cartridges of solid fuel that are fed by a mechanism similar to the one that feeds cartridges consisting of case/primer/powder/bullet.
-- Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Re:They already had a design like this
by
markmoss
·
· Score: 3, Interesting
It was an automated system that aimed for the eyes, but got cancelled due to bad press. Oh my. That would certainly upset those people that imagine war can be made more humane... But the reality is, to fight a war you either kill people or wound them. Wounding is more effective, because then their buddies have to stop fighting and take care of them. A laser in the eyes would be very, very effective in this way. I think, unlike most non-fatal gunfire wounds, laser blindness would be quite permanent. If we deployed this system, the next country to get crossways of us would wind up with their streets full of blind beggars afterwards -- a hell of a drag on a third world economy, and assurance that what happens when you p*ss off America would be remembered for a century, at least. Is that good or bad???
Slashdot Mirror
Sounds like they put a fire-finder radar tracking station onto a laser. They've had the ability to plot trajectory and such of incoming shells for quite a while, but now they'll be able to do something about it other than leave.
Unfortunately, I have suspicions if this will ever make it to deployment. The U.S. also has an anti-satellite laser weapon that has been tested and confirmed to work by overloading the circuits -- and it was nixed because of the poltical tension it would create.
I know the airborne laser (uses the same chemical type laser) was capable of shooting down rockets by weakening the metal skins, which the forces of flight would thus rupture and cause the thing to fly apart, but are artillery shells really that delicate?
-
What's to stop them from using these things on people? They have amazingly accurate targeting systems and they're cheap to fire (article says 25 cents (maybe dollars, I forget...) per shot.
So what's to keep the defense dept. from using these things for assassinations, or ground warfare?
Would that be cruel and unusual?
Here's a question: is there a "right of the people" to keep and bear these? The idea doesn't sound assuring, I must say: what kind of signature would it leave. Bullets can be tracked, but this -- would there even be a body left?
I'm not trying to complain or predict horrors, because I'm all about the advance of tech. I just want to know a little more about this kind of thing.
Also: it's eerie that the article only mentions uses of these for defense, and not for attack, covert (which I think is a promising potential use for this technology) or otherwise. Just considering it's a time of "war" and all.
The US Army's HEL sites:
http://www.smdc.army.mil/FactSheets/THEL.html
http://www.smdc.army.mil/FactSheets/HELSTF.html
TRW's contribution:
http://www.trw.com/thel
-Mark
Not as easy to steer as a laser but extremely difficult to defend against. Good for anti-aircraft as well, since colanders have poor aerodynamics. Anything not detonated by ball bearings doing many kilometers a second would be thrown well off course. Not that this is not necessarily an advantage, since certain nations are reknowned for just carpeting the target area with ordinance and knocking something off course might make it more accurate.
Got time? Spend some of it coding or testing
Mirror coating, etc. doesn't make a difference.
To be blunt, this is wrong. I do agree, however, that just polishing up a stainless steel shell until you can shave in front of it probably won't make enough difference. Most mirrors don't reflect nearly enough light.
On the other hand, such powerful lasers are hard to make and very expensive. It would be tempting to make them just barely strong enough to work against existing designs which have no defense against such countermeasures. If a spinning (or randomly tumbling), mirrored shell, can cut down the rate of heating by something like 30%, and there's some extra heat-shielding inside, it might be enough to survive.
All kidding aside, you also can't rule out, as I said, revolutionary new developments in mirrored armor. I mean, if there was no way to deflect the beam, there would be no way to generate or aim it!
BTW, Tom Clancy is a novelist, not a physicist. His entire livelihood is sounding plausible about things he doesn't really understand.
Besides, in the battle between bigger armor and bigger guns, the guns always win eventually.
Ah, but which is which? This is an odd historical precedent to apply in favor of a defense mechanism.
Is anyone else wondering why we are spending so much money on the missile defense system? This seems to have solved the problem of missile defense much more elegantly (and more cost effectively?) Maybe I'm missing something.
Co-founder and designer at Music Nearby: http://musicnearby.com
Weapons treaties are there to be ignored by a the parties signing them.
THink of it, you sign a treat to (say) not research biological weapons for offensive purposes, say, like Russia did. Then, you secretly violate the treaty, and now you have weapon the other side doesn't have. Its happened in the past, it'll happen in the future.
Weapons treaties only penalize the honest countries. Dishonest countries won't care. At least we actually do (for the most part) obey our treaties.
Does this jive with the fox news article?
Yes. But it doesn't tell the whole story.
The lasers they're talking about are spinoffs of the Star Wars missile defense system. They had to get a LOT of energy into a beam quickly, to shoot down missiles while still in space, or to bounce off a mirror in space to get them on their way up. One shot, one dead nuke, so cost wasn't much of an object.
Neither was portability: You had either a fortified underground bunker as big as you wanted, or a satellite in zero-G.
So they did something very strong, effective, big, and expensive.
But lasers are EASY. Excluding superradiants (which are easier, if you've got the materials) all you need is a couple of well-alligned mirrors, one of 'em slightly leaky, with an "inverted population amplification light amplification medium" between them.
For "inverted population light amplification medium" read "smoke from a fire".
The medium must have the following characteristics:
It has a state transistion (an "excited state", a "ground state" or less-excited state, and an allowed transition between them) with an energy difference corresponding to a usefully energetic photon.
It must have significantly more of its atoms or molecules in the more-excited state than in the less-excited state. (This is the "inverted population" part.)
It must have ENOUGH of a surplus of more-excited particles to produce a usable amount of power if you extracted the energy difference by de-exciting enough that you're down to 50/50 (or de-exciting them all if there's a further transition that drains the less-excited state).
It must be transparent and reasonably uniform (i.e. non-distorting) at the light frequency corresponding to the state transition.
When you burn darn near ANYTHING the resulting molecules start out excited. If they meet the other criteria you've got a suitable medium for a chemically-pumped laser.
Burn a suitable fuel in a long, thin, rocket flame and run the exhaust at right angles between the pair of mirrors. You'll have a laser beam coming out as long as the flame lasts. Chose the right material and a large fraction of what would have been the heat of combustion ends up in the laser beam.
Now there are some fancy and deadly fuels (fluorine comes to mind) that make an exhaust where the bulk of the energy can be extracted by a single transition. This is nice and efficient. And you don't want to be ANYWHERE NEAR them when in use, due to the toxic nature of the exhaust. So if you're going to be shooting down a nuke from a fort in the desert they're fine.
But there are LOTS of others that are simpler, and might be more suitable for a battlefield.
I expect that eventually we'll see a chemically-pumped laser rifle or pistol, about the same size as a normal rifle or pistol, with an optical cavity where the barrel would be, powered by cartridges of solid fuel that are fed by a mechanism similar to the one that feeds cartridges consisting of case/primer/powder/bullet.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
It was an automated system that aimed for the eyes, but got cancelled due to bad press. Oh my. That would certainly upset those people that imagine war can be made more humane... But the reality is, to fight a war you either kill people or wound them. Wounding is more effective, because then their buddies have to stop fighting and take care of them. A laser in the eyes would be very, very effective in this way. I think, unlike most non-fatal gunfire wounds, laser blindness would be quite permanent. If we deployed this system, the next country to get crossways of us would wind up with their streets full of blind beggars afterwards -- a hell of a drag on a third world economy, and assurance that what happens when you p*ss off America would be remembered for a century, at least. Is that good or bad???