Forget the bullets..It's lazer time. Well maybe not just yet.


PDA






bg
August 25, 2005, 01:03 AM
This is pretty interesting. I'd sure hate to get in the way of the "stream" >
http://www.yahoo.com/_ylh=X3oDMTEwdnZjMjFhBF9TAzI3MTYxNDkEdGVzdAMwBHRtcGwDaW5kZXgtY3Nz/s/251757

If you enjoyed reading about "Forget the bullets..It's lazer time. Well maybe not just yet." here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!
Husker1911
August 25, 2005, 02:33 AM
I've not read your link, sorry. But the thread title reminds me of a sales statement and life statement I make. Namely: in 50 years, when people are using proton blasters and laser photon weapons, a .38 snubbie will still be just as damn effective as it is today. There's something about 148 grains of solid lead hurtled at 800 fps through a two inch barrel that proves physics doesn't lie.

Sindawe
August 25, 2005, 02:39 AM
Such weapon systems are fun the think about, and I don't doubt would be fun to shoot, but in a hairy situation like combat, I think this will hold true for centuries to come:

Alien: Such primitive weapons you have.
SG-1: Ya, but they WORK.
:D

Rabid Rabbit
August 25, 2005, 07:21 AM
I've been thinking about getting a laser for my Glock and this one has the power I need, no more wimpy 5 milliwatt for me. I'm sure they will be able to shrink the size down in a couple years.

Dionysusigma
August 25, 2005, 10:15 AM
Like a computer that can fit in just one room and hold thousands of pieces of information? ;)

My question is this: Why limit yourself to knocking down missiles? Why not shoot down other X-Wing fighters?

Crosshair
August 25, 2005, 10:32 AM
Lets see you're fancy lazer rifle work in the rain/mist/dust. Oops, guess the energy gets absorbed by the water in the air and gets blocked by the dust. My bullets can penitrate those "barriers" just fine. My tin foil armor works well too. :D

Energy weapons are relativly easy to "shield". Projectile weapons are much more difficult.

benEzra
August 25, 2005, 11:38 AM
By a happy coincidence, the F-35 fighter has an empty bay behind the cockpit that contains the lift fan in the STOVL versions. It can be fitted with a fuel tank, but it could also swallow a "fridge sized" laser system.

And leading into that empty bay in the STOVL version is a PTO shaft capable of delivering 35,000 shaft horsepower to the lift fan, which by happy coincidence could also drive a REALLY big electrical generator in that space...35,000 horsepower is 26 megawatts, so you wouldn't need to run the engine anywhere near full power to drive a megawatt-class laser, even assuming conversion inefficiencies...

So you could eventually envision an F-35 variant armed with a megawatt-per-second infrared laser capable of engaging hostile aircraft and missiles at great ranges with enough power on target to take them out...sounds pretty interesting indeed.

zahc
August 25, 2005, 12:18 PM
And no bullet drop to worry about. And due to those pesky relativistic effects, the muzzle velocity is ALWAYS the same!

CARRY'IN
August 25, 2005, 12:58 PM
Destructive lasers are very easily defeated; this research is a cover for nuclear weapons research, as are many other laser research programs. The big problem with hydrogen (fusion) bombs is that you have to use an atomic (fission) bomb to light one off. Laser ignition would allow much smaller and more powerful (like we really need that) H-bombs. Ant-nuke organizations howl unless there are cover programs like this in place.

DelayedReaction
August 25, 2005, 01:08 PM
Actually, the technology offered here is much better as a defensive weapon. Since the laser beam moves at relativistic speeds, you can use a tracking system to point it at a missile and fire. Given enough warning it could make our fighters nearly impossible to destroy by conventional weapons.

I could also see this thing doing a wonderful job of hitting enemy missiles while they're still on the rack of the aircraft.

Lasers also have a major advantage over missiles and guns; they don't run out of ammunition.

CARRY'IN
August 25, 2005, 01:43 PM
Not really. Even very thin reflective and ceramic armors defeat any wavelength of laser beam. And it takes very little lateral movement to befuddle a tracking system that has to stay focused on what is essentially an object traveling as fast as a bullet. Physics argue against it. The company is making plenty of money though. They must have contributed to someones campaign.

MechAg94
August 25, 2005, 01:44 PM
I am also imagining an anti-aircraft armored vehicle with one or two of these mounted that could knock out incoming missiles, bombs, artillery, or aircraft.

It is nice to see we might have real active missile defense in place that aren't just another missile.

Would a laser ignited H bomb be any cleaner as far as fall out and stuff?

HankB
August 25, 2005, 02:48 PM
this research is a cover for nuclear weapons research, as are many other laser research programs. I doubt that this laser has any relation to nuclear weapons research.

Lasers used in fusion research fill entire buildings. BIG buildings. The National Ignition Facility's goal is to deliver 1.8 megajoules to a millimeter-sized target in a pulse that's so short the equivalent power is around 500 terawatts. Smaller ("smaller" is a relative term here) lasers like the NOVA system also fill buildings, and are used for fusion research which can be related to weapons, but they're a long, LONG way short of being able to ignite an H-bomb.

To put this in proper perspective, the detonation of just one ton of TNT releases about 4184 megajoules, more than three orders of magnitude greater than the goal of the NIF.

Thermonuclear weapons are detonated by fission explosions, probably with yields on the order of kilotons of TNT - at least.

The laser mentioned here is most likely to be used against the guidance system of IR-guided missles like the Stinger and the Russian equivalent. And even then, tracking, focus, and detection issues have to be solved, along with things like keeping the laser optics clean in a combat environment and dealing with airborne dust, smoke, clouds, etc. I don't see it being used to actually shoot down anything by 2007.Lasers also have a major advantage over missiles and guns; they don't run out of ammunition. Power supplies require fuel, and some lasers use consumable chemicals as the lasing medium.

Gifted
August 25, 2005, 03:58 PM
Even very thin reflective and ceramic armors defeat any wavelength of laser beam. I've hashed this out with people on another forum. It's impossible to keep a surface clean and reflective enough in a combat environment. Mirrors used with lasers less than a tenth as powerful as this are frequently liquid cooled to keep them from breaking.

1Kw isn't much. the 15Kw they're making would be servicable; with current systems they already have ways to keep the lenses clean. 150Kw, or benEzra's megawatt, definitely works.

Biggest question here is how long does it take to burn through, say, a couple of millimeters of aluminum(aircraft) or a couple of inches of steel(tanks and other AFVs)?

CARRY'IN
August 25, 2005, 04:13 PM
There is alot of star wars baloney out there serving the companies that are stealing the taxpayers blind. All the top scientists NOT employed by the government or defence industry say star wars type devices like lasers and anti-missile missile systems either will not work or can be easily defeated with simple measures. For instance a slight instability in a ballistic missile warhead may reduce its accuracy from a hundred yards to a thousand, but with nukes does it make that much difference? But that instability makes it virtually impossible to focus a beam on. Remember those patriot missiles we were so proud of during desert storm? How accurate they were? All B.S. As is star wars in general.

Chrontius
August 25, 2005, 07:30 PM
Anyone else read Popular Mechanics?

Anyone else see the fuel-cell motorcycle? The one with a 6Kw fuel cell/capacitor bank?

Anyone else going to build "the Akira" when they come out? :D


Would a laser ignited H bomb be any cleaner as far as fall out and stuff?
Incredibly more so.

I've hashed this out with people on another forum. It's impossible to keep a surface clean and reflective enough in a combat environment. Mirrors used with lasers less than a tenth as powerful as this are frequently liquid cooled to keep them from breaking.

The laser is called the HELLsomething. HELL stands for "High Energy Liquid Laser"

Remember those patriot missiles we were so proud of during desert storm? How accurate they were? All B.S. As is star wars in general.
My grandfather built those missiles. To shoot down *bombers*. Only with the Patriot-3 did the antimissile interceptor really come of age. Patriot-1 was programmed to go for engine shots to stop aircraft, which frequently did not destroy the warhead, and Patriot-2 simly couldn't be powerful enough, designed as it was to throw shrapnel at the missile. Patriot-3 is a hit-to-kill kinetic missile, and does its job far better and cheaper; cheap enough that two missiles is the rule of the day for antimissile shots, each shot more effective than their predecessor.

Gifted
August 25, 2005, 11:19 PM
The laser is called the HELLsomething. HELL stands for "High Energy Liquid Laser" I wasn't refering to the laser, I was referring to the "thin reflective materials" that were claimed to be able to counter the laser. Even the best reflective surface absorbs some energy.

The key here is to make the laser powerful enough to deliver a killing blow within a few millliseconds, if not less.

Crosshair
August 26, 2005, 06:11 AM
I'd love to see what happenes to the lazer energy that gets reflected off of the surface of whatever is getting shot at. Even if the object is destroyed, do you really want all that lazer energy going who knows where. ICBM warheads are easy to protect against lasers, since they spend their time inside the missle. Easy to keep them to a mirror finish.

Can anyone answer my question as to what will happen in high humidity/clowds/dust. Lasers beams also spread out, not as fast as say from a flashlight, over distance. *goes and play's with laser boresighter in basement* My boresighter beam spreads from about 1mm at the "muzzle" to about 2mm at 35 feet. Lets say that our big laser has MUCH better optics than my boresighter. If my math is correct, (PLEASE correct me if I made a mistake) a 1" beam will spread to a circular area about 17.6" in diamiter at one mile. At 10 miles, it will spread to 176". 100 miles, to 1760" or 146.6 feet.

146.6'/2=73.3
pi*(73.3'^2)= 16,886.2 ft^2

Now to computer energy per square foot.
15Kw = 15,000w
15,000/16,886.2 = 0.8883 watts per square foot.

Even if we assume 150Kw, this gives us only 8.883 watts per square foot at 100 miles. If we use 15Kw at 10 miles we get.
168.70 ft^2
15,000/168.70 = 88.91 watts A 100 watt lightbulb has more energy/ft^2 than this laser.

Does someone have better figures as to how much a laser beam spreads. I don't think a laser boresighter is the best thing to use for comparison, but it was the best I had.

benEzra
August 26, 2005, 12:04 PM
Destructive lasers are very easily defeated; this research is a cover for nuclear weapons research, as are many other laser research programs. The big problem with hydrogen (fusion) bombs is that you have to use an atomic (fission) bomb to light one off. Laser ignition would allow much smaller and more powerful (like we really need that) H-bombs. Ant-nuke organizations howl unless there are cover programs like this in place.
Not when you get into multi-megawatt-per-second continuous wave IR lasers, they aren't. IR lasers are useless for nuclear weapons applications (those are all ultra-short-pulse visible/UV lasers), but actually do work very well against lightly armored targets like missiles and aircraft.

No surface is 100% reflective. Even 99% reflectivity in infrared is unattainable in real world applications, but even assuming you could get 99% reflectivity, if you are delivering 5 megawatts, that 1% is still 50,000 watts. A 50-watt infrared CO2 industrial laser can cut sheet steel; a thousand times more power, on a relatively fragile, highly stressed aluminum skin...instant structural failure.

I have a video of a deuterium fluoride laser shooting down two Katyusha rockets by cooking off their warheads in flight, and that wasn't even a particularly powerful laser; I'll see if I can scrounge it up and post it.

Laser ignition isn't going to make H-bombs any smaller. The W-80 (Tomahawk-N warhead, dial-a-yield up to 150 kT) is the size of an office wastebasket and weighs 290 pounds, and most of that weight is in the fusion stage that you have to have even with a hypothetical laser ignition system). And you'd need a different wavelength laser to implode the fusion stage (current H-bomb designs use thermal radiation in the X-ray range to compress the tamper).

GEM
August 26, 2005, 12:36 PM
It will never work!

Thursday, December 26, 1861.
Washington, DC.

President Lincoln directs Chief of Ordnance to order 10,000 Spencer repeating rifles.

benEzra
August 26, 2005, 02:11 PM
I'd love to see what happenes to the lazer energy that gets reflected off of the surface of whatever is getting shot at. Even if the object is destroyed, do you really want all that lazer energy going who knows where.
The reflected beam is no longer tightly collimated, so although specular reflection could be a problem at relatively close ranges, if you're engaging aircraft and/or spacecraft (satellites, missile RV's) everyone and everything is probably going to be far enough away not to be a problem. You'd get a lot more risk from a LANTIRN pod targeting stuff on the ground, I'd imagine. Infrared-blocking glasses or visors (like pilots may already wear) might be required for those airborne, though.

IR is attenuated somewhat in the lower atmosphere, but I don't know how significant that would be.

ICBM warheads are easy to protect against lasers, since they spend their time inside the missle. Easy to keep them to a mirror finish.
See above re: trying to reflect a multi-megawatt-per-second IR beam.

If it's in the missile, you can blow up the missile. But the warhead's RV (reentry vehicle) is a LOT more heat resistant than the missile body (it's designed to keep the warhead from frying during a 17,000 mph reentry into the troposphere, i.e. temps approaching that of the sun's surface) which is why the Airborne Laser and others would only be shooting at missiles while they're in the boost phase. The warhead would actually be better off separating from the missile as soon as possible.

Can anyone answer my question as to what will happen in high humidity/clowds/dust.
One of the reasons for using mid-infrared is that it's less attenuated by atmospheric water vapor, as I understand.

Lasers beams also spread out, not as fast as say from a flashlight, over distance. *goes and play's with laser boresighter in basement* My boresighter beam spreads from about 1mm at the "muzzle" to about 2mm at 35 feet. Lets say that our big laser has MUCH better optics than my boresighter. If my math is correct, (PLEASE correct me if I made a mistake) a 1" beam will spread to a circular area about 17.6" in diamiter at one mile. At 10 miles, it will spread to 176". 100 miles, to 1760" or 146.6 feet.

146.6'/2=73.3
pi*(73.3'^2)= 16,886.2 ft^2

Now to computer energy per square foot.
15Kw = 15,000w
15,000/16,886.2 = 0.8883 watts per square foot.

Even if we assume 150Kw, this gives us only 8.883 watts per square foot at 100 miles. If we use 15Kw at 10 miles we get.
168.70 ft^2
15,000/168.70 = 88.91 watts A 100 watt lightbulb has more energy/ft^2 than this laser.

Does someone have better figures as to how much a laser beam spreads. I don't think a laser boresighter is the best thing to use for comparison, but it was the best I had.
Most class II and IIIA consumer-product lasers (laser pointers, boresighters, etc.) purposely use crappy optics (a spreader lens or whatever) in order to make them eyesafe. The last thing you want from your boresighter is for the beam to reflect off a mirror and burn a hole in your retina (even a 5-milliwatt laser pointer, were it to produce a diffraction-limited spot on your retina through your eye's lens, would run about 1 megawatt/square meter of delivered power on that spot, which is more than staring at the sun IIRC).

As far as the beam spread of a big military laser, adaptive optics systems (like the ones allowing ground-based telescopes to see better than the Hubble) were invented for these lasers, allowing them to operate at or near the diffraction limit under most circumstances. The diffraction limit for a 1-meter telescope in visible light is IIRC around 0.1 arcsecond, so double the diff limit for a longer wavelength laser and you're still looking at around 0.2 arcsecond if I'm figuring right. I did a quick calculation and that's a fraction of an inch at 5 miles, or just under 6.2 inches at 100 miles. IIRC, the diffraction limit scales linearly with the mirror size, so even a small 1-foot mirror should still be able to give you a 6-inch diffraction limited beam spot at 33 miles or so.

MillCreek
August 26, 2005, 03:16 PM
I live in the Seattle area. Only a few years ago, the Air Force had an airborne laser demonstrator based at Boeing Field for two or three years for testing. It was mounted on a 747 airframe, and it was a chemically-fueled laser designed to shoot down ICBMs in the boost phase, if I remember correctly. Or perhaps it was designed for theater missiles. I remember there were some articles in the Seattle papers about it. I wonder if that program is still active. I recall that I was impressed with the chemically-fueled aspects of it, and it could carry enough fuel for 20-30 shots, or something like that.

Ol' Badger
August 26, 2005, 03:49 PM
"These are the days of lasers in the jungle somewhere!"

Cool if it works. Wounder if there will be a waiting period on them?

benEzra
August 28, 2005, 11:39 PM
I live in the Seattle area. Only a few years ago, the Air Force had an airborne laser demonstrator based at Boeing Field for two or three years for testing. It was mounted on a 747 airframe, and it was a chemically-fueled laser designed to shoot down ICBMs in the boost phase, if I remember correctly. Or perhaps it was designed for theater missiles. I remember there were some articles in the Seattle papers about it. I wonder if that program is still active. I recall that I was impressed with the chemically-fueled aspects of it, and it could carry enough fuel for 20-30 shots, or something like that.
That'd be the Airborne Laser program, and IIRC the airplane may be designated YAL-1A (Y=Prototype, A=Attack, L=Laser?). The laser system is a chemical oxygen-iodine laser (COIL) with a beam power that's classified but probably in the neighborhood of five megawatts or so? and the beam is delivered via a rotating turret in the nose. The battle management center looks straight out of Star Trek to me... :D

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

Oh, in light of the discussion of mirror size and diffraction limits above, check out the turret mirror diameter. That's probably at least two meters, meaning the diffraction limit of that system is probably even better than the above guesstimate. I'd expect that even with less-than-perfect adaptive-optics correction, you'd easily get sub-6-inch spot sizes at 100 miles or more.

chopinbloc
August 29, 2005, 05:55 AM
ok, maybe i'm a little short sighted but this would be sweet for fixed, land based, perimeter defense systems. we have had radar systems that track mortar, rocket and artillery rounds since the early seventies. we have infrared cameras on extendable towers that remind me of the eye of sauron in lotr. add this and an installation would be impregnable for miles. one could blast rounds out of the sky and burn troops on the ground miles away. not only would the enemy be afraid to fire, he'd be afraid to get within line of sight. it shouldn't be that difficult to pipe the light up to the top of say a hundred foot tower, either. dear sweet jeebus, the life of an insurgent is getting tougher day by day.

btw for an interesting defense against coherent light read john ringo's books. forget which one, but a giat tank used thousands of gallons of water showered in front like a curtain.

If you enjoyed reading about "Forget the bullets..It's lazer time. Well maybe not just yet." here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!