Laser weapon successfully tested


PDA






Preacherman
May 7, 2004, 10:03 AM
From My Way News (http://news.myway.com/top/article/id/401978|top|05-07-2004::08:06|reuters.html):

Israeli-U.S. Laser Downs Long-Range Missile in Test

May 7, 7:54 AM (ET)

JERUSALEM (Reuters) - A laser beam under joint Israeli-U.S. development destroyed a long-range rocket for the first time in a test in the skies over the American Southwest, Israel's Defense Ministry said on Friday.

Israel has sought an effective defense against ballistic missiles since 1991 when Iraq launched Scuds into the Jewish state during the first Gulf War. It has since developed the Arrow anti-ballistic missile with U.S. funding.

"This is a significant step forward," a ministry spokesman said of the test on May 4 of the "Nautilus" Mobile Tactical High Energy Laser (MTHEL) held at the White Sands Missile Range in New Mexico.

Israel sees the Nautilus as another potential countermeasure to possible ballistic attack by enemies, which would include most Arab states and Iran. In turn, they see Israel's undeclared nuclear arsenal as the biggest strategic threat to the region.

The Nautilus laser is being developed mainly by U.S. aerospace giant Northrop Grumman Corp with the help of several Israeli high-tech firms specializing in optics and military hardware.

"The (Nautilus) project has the potential to fill an important operational need for Israel," said Shmuel Keren, the Israeli military's director of weapons systems and infrastructure development.

"The (Nautilus) system can answer our need for a system which can intercept missiles and cruise missiles for which currently there is no effective solution."

The Defense Ministry declined to elaborate on the test or the exact range of the intercepted missile.

In earlier tests the MTHEL laser had successfully eliminated 28 short-range Katyusha rockets and five artillery shells in flight as well as several "hostile objects" on the ground.

If you enjoyed reading about "Laser weapon successfully tested" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!
benEzra
May 7, 2004, 10:07 AM
Very cool. If it's just a miniaturized THEL, then it's a deuterium fluoride laser in the low megawatt range, beaming in the infrared. (For comparison, a typical laser pointer is 1 to 5 MILLIwatts and is brighter than the sun.

Kharn
May 7, 2004, 10:33 AM
I wonder if there are any plans to ship one or two of them over to Baghdad and see if it can take out mortar rounds in-flight?
I guess programming it to not shoot down friendly fire would be the biggest challenge.

Kharn

Jay Kominek
May 7, 2004, 10:35 AM
Power source?

Leatherneck
May 7, 2004, 10:54 AM
Power source at WSMR is the normal range grid. Anticipated power source for a fielded weapon system will be batteries and very big capacitor banks. That, plus the high cooling demand, is what makes it a three-tractor-trailer type of rig right now. The challenge will be to shrink it to HMMWV size.

Ironically, the push for this since the mid-90s has been the Arab rocket threat to Israel. What a small world.

TC
TFL Survivor

edit to add: I don't know why they're touting this as a "first" kill of a rocket, since Nautilus killed several Katyusha rockets at WSMR in tests in 1996.

flatrock
May 7, 2004, 11:23 AM
I still think the Airborn Laser project is nicer.

http://www.boeing.com/defense-space/military/abl/flash.html

It probably has something to do with the fact that the company I work for supplies products used in the ABL program. :)

Mr. Mysterious
May 7, 2004, 11:25 AM
YES my plan for fitting my sharks with freaking laser beams is one step closer.

Back to topic...

I wonder what the range on this thing is? You need it to blow up the missile far enough away so that if it is carrying BC it will rain on someone else instead of you.

Shooting down artillery shells is pretty cool.

benEzra
May 7, 2004, 12:09 PM
Power source?
The only electrical power it needs is for the pumps and electronics. The power for the laser beam itself comes from combustion of two fuels in a rocketlike combustion chamber. The chemical reactions produce a supersonic jet of extremely hot gases in which certain molecules are in very high energy states. After leaving the combustion chamber, the gases pass at right angles through an optical cavity (laser chamber) with mirrors on both sides just like an ordinary gas laser, and from there it's the same as an ordinary gas laser (stimulated emission driven by the photons bouncing back and forth between the mirrors). The beam is extracted from the chamber(s), focused and collimated, and directed at the target.

Since the main power source is the fuel itself, you don't have to have gigantic electrical generators and can shoot as long as your fuel lasts (as long as your system cooling is good enough). It's also a continuous beam, not a pulsed beam like many high-wattage research lasers, so the energy in terms of joules on target is immense (>1 megajoule per second), so your heating rate on the target (assuming perfect absorption) is like a million-watt heater.

Here's some older links (not sure if they still work) regarding the original THEL and the ABL (which is a chemical oxygen-iodine laser, IIRC):
http://www.st.northropgrumman.com/mediacenter/page.cfm?PageID=5508&SiteSectionID=0
http://www.st.northropgrumman.com/mediacenter/page.cfm?PageID=5509&SiteSectionID=0

The Airborne Laser aircraft (which may be designated AL-1A):
http://www.airbornelaser.com

entropy
May 7, 2004, 01:10 PM
Any plans for a rifle in the 40 watt range?:evil:

armoredman
May 7, 2004, 01:14 PM
I still wanna truck mounted rail gun....

atek3
May 7, 2004, 03:47 PM
one downside is that the DF (deuterium floride gas) is released to the atmosphere, DF is EXTREMELY toxic and corrosive. It eats glass! If you get it on you the burn likely won't kill you, but the calcium flouride precipitate in your heart might :(

atek3

benEzra
May 8, 2004, 05:54 PM
I *think* the amount of deuterium used is small; the main fuels are ethylene (C2H4) and nitrogen trifluoride (NF3) and the deuterium is injected downstream of the combustion chamber and upstream of the optical cavity. Excited DF is the intermediate product that actually does the "lasing," but I'm not sure if it breaks down in the exhaust or if it is converted to something else. Given its extreme reactivity (due to fluorine's extreme electronegativity), I would suspect that it quickly reacts with other stuff to form harmless compounds--just don't stand in the exhaust vent . . .

The beauty of a chemical laser like this is that you don't have to "pump" the optical cavity to support the population inversion, since the deexcited molecules are continuously exiting the chamber and new excited molecules are continuously entering. Also, you can tap the energy of the majority of excited molecules in the chamber instead of just a few % like most continuous-wave lasers.

BTW, the fuels for the airborne laser are hydrogen peroxide, potassium hydroxide, and chlorine, producing excited O2; iodine gas is injected upstream of the optical cavity, and the activating reaction is I2 + 4 O2* --> 2 I* + 4 O2; the activated singlet iodine is what does the "lasing."

TBeck
May 8, 2004, 08:39 PM
Any plans for a rifle in the 40 watt range?

Just what you see on the shelf, pal.

What is want to know is whether the scientist makes little quotation signs with his fingers every time he says the word "LAY-sur"?

atek3
May 8, 2004, 09:57 PM
ethylene (C2H4) and nitrogen trifluoride (NF3)

Why are these fuels used? NF3 is really toxic also.

atek3

Telperion
May 9, 2004, 01:30 AM
Any plans for a rifle in the 40 watt range?Why wait? There's a 45 W argon laser on ebay now. Looks like a fixer-upper though.

I think I'll stick to HeNe and diode lasers. :D

The_Antibubba
May 9, 2004, 01:43 AM
Actually, the 40 watt rifle was all set for civilian release, but they had to withdraw it because of the pistol grip and bayonet lug. :D

I'll hold out for the carbine.

Oleg Volk
May 9, 2004, 05:28 AM
Interesting that the idea of a chemical laser pre-dates the actual implementation. http://lib.ru/TOLSTOJA/giperbolojd.txt was written in 1926-27 and updated in 1927. "Engineer Garin's Hyperboloid" basically describes an MG-sized device that focuses the light from a "chemical candle" into a thin, hot beam. Not sure if the idea was original to the writer or ripped off from somebody else.

benEzra
May 9, 2004, 03:46 PM
Why are these fuels used? NF3 is really toxic also.
NF3 is used so that the end product of the initial reaction includes fluorine with an electron in an elevated energy state (i.e., kicked up a level from where it would normally rest). Fluorine reacts pretty strongly with hydrogen (deuterium is just another name for hydrogen-2). When the deuterium is injected, I would surmise that the fluorine reacts with the deuterium and transfers the excited electron state to the deuterium atom.

(WARNING: THE FOLLOWING PARAGRAPH CONTAINS QUANTUM PHYSICS. READ AT YOUR OWN RISK. :D)
Remember that the mechanism of light emission in all lasers is an electron in an excited state. Ordinarily, the electron will fall back to its ground state in its own time and emit light of a specific frequency (a familiar example of this is phosphorus glowing green in the dark after you've exposed it to light, or a chemlight stick.) But if an electron in an excited state gets hit with a photon of that wavelength BEFORE it emits, it will emit immediately, resulting in two photons. (This is called stimulated emission.) The important thing is that the two photons are traveling in exactly the same direction, at the same wavelength, and are in phase. So, if you have a chamber full of atoms in excited states, and you start a photon traveling through the chamber, a metric boatload of photons will come out the other end of the chamber, and they'll all be traveling in synch (same wavelength, same phase, same direction).

BTW, "laser" is an acronym for Light Amplification by Stimulated Emission of Radiation.

El Tejon
May 9, 2004, 04:31 PM
Additionally everyone could see a lot better after the test.:D

MeekandMild
May 9, 2004, 05:10 PM
Additionally everyone could see a lot better after the test. I doubt that. I know you meant it as a joke, but even milliwatt laser light is eye-dangerous. Lasers this powerful will be dangerous fifty or a hundred or two miles away.

Imagine you are out at your desert shooting range up in the mountains above Lincoln NM, and from nowhere comes a tiny stroke of light reflected from a laser test miles away down at White Sands. BLAM! You are perminently blind and you have no idea how, from where or why did the light come.

Or maybe you are hunting javalinas outside Terlingua Texas. It doesn't matter, how far away you are. In clear air laser light will carry a looonnnnggg way.

Obviously if they are announcing this test they have already made similar tests for years in secret. So how many air to air (think shooting down toward the ground) lasers are they testing? :scrutiny:

El Tejon
May 9, 2004, 06:10 PM
Meek, yeah, humor (attempted humor) on the 'net, imagine that.:D

Danger? Mmmm, I don't know. Isn't this out in the Western Wastes where Hayzeus left his zapatos? Would somewhere at sea be better?

Telperion
May 9, 2004, 06:23 PM
Perhaps, but then you'd have to worry about the sharks with frickin' laser beams attached to their heads. :D

El Tejon
May 9, 2004, 06:41 PM
I've got a whole bag of "shhh.":D

benEzra
May 11, 2004, 08:33 AM
Obviously if they are announcing this test they have already made similar tests for years in secret. So how many air to air (think shooting down toward the ground) lasers are they testing?
Tends of thousands. Those LANTIRN (sp?) targeting pods for guiding laser-guided munitions are infrared lasers in the 1 to 3 watt range, I think. But if you are think Star-Wars-type ground-attack lasers based on a fighter-sized aircraft, the technology is decades away. A fighter can't carry large tanks of fuel for chemical lasers, and the power requirements for an electric-powered laser are immense (a 5-megajoule-per-second laser with a 10% end-to-end system efficiency would require about 70,000 horsepower on the generator input shaft). HOWEVER, it might be noted that the F-35 fighter (Joint Strike Fighter) STOVL variant has an engine-driven lift fan that draws 35,000 horsepower in hover, so replace the lift fan with a compact generator and you might be able to field a fighter-based low-megawatt-class laser--but it hasn't been done yet. Also, a laser is great for attacking thin-skinned targets like aircraft and missiles, but lousy at attacking ground targets; any armor that is proof against a depleted-uranium long-rod penetrator traveling at Mach 5 is going to laugh at a light beam, even one in the megawatt class.

The Airborne Laser is a putative air-to-air or air-to-space aircraft-based laser system, but it's a chemical laser (combustion driven) and takes up most of a Boeing 747.

ThreadKiller
May 11, 2004, 09:50 AM
Whoa!!!! This thing has got to be hell on the ozone layer. It must be STOPPED now!!!! Global warming!!! We're DOOMED!!!!

And since it's burning dangerous chemicals, obviously Chevron and Halliburton have to be involved.

Quite obviously this "weapons system" was developed by the vast right wing conspiracy to destroy the environment and oppress the working class.

Dick Cheney's fingerprints are all over this one, boys.

Tim

Mr. Mysterious
May 11, 2004, 11:03 AM
Speaking of the JSF, I thought that there was some form of laser being built into it?

benEzra
May 11, 2004, 02:07 PM
Probably a laser target designator.

simon
May 11, 2004, 03:07 PM
That, plus the high cooling demand, is what makes it a three-tractor-trailer type of rig right now.
Thats exactly what it is...Two trailers of fuel and the other with the large gimble with the laser.I was slightly involved with the early logistics on the THEL program..

rich2u
May 11, 2004, 03:24 PM
I'm surprised that this is big news that they shot down a rocket. They have already used it to shoot down artillery shells. That would have to be a hell of a lot harder to track, target & hit than a rocket wouldn't it?

MeekandMild
May 11, 2004, 10:31 PM
any armor that is proof against a depleted-uranium long-rod penetrator traveling at Mach 5 is going to laugh at a light beam, even one in the megawatt class. Ben, I don't really care about armor nor military devices. What I care is Civilian Class Eyeballs, Mark-I. I used to fly with USAF nimrods. I know how often things go awry and I don't want any joker 50 miles away missing the target and zapping me while I'm out on the tractor.

benEzra
May 14, 2004, 11:27 PM
MeekandMild,

Good point. I think the water vapor in the denser lower atmosphere helps attenuate specular reflections at long slant distances, so the main eye danger would be to troops in-theater (who would probably be issued with infrared-opaque glasses). One reason they're going through all the trouble to stick the Airborne Laser on a 747 is to get the beam source up into the stratosphere where water vapor attenuation is less of a problem, allowing the laser to shoot things down hundreds of miles away. Since THEL is more of a point-defense-type system, propagation range is less of an issue.

If you enjoyed reading about "Laser weapon successfully tested" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!