Posted on 09/01/2005 6:37:55 AM PDT by Momaw Nadon
DARPA's HELLADS (High Energy Liquid Laser Area Defense System) will be light enough to fit on a fighter jet or drone aircraft, and yet powerful enough to fire a 150 kilowatt beam of energy. Star Wars laser cannon may be closer than you think.
High energy laser weapons already in development are powerful enough to bring down missiles (see MTHEL - Mobile Tactical High Energy Laser). However, their very large size has precluded placement on any but the largest planes. The main weight problem comes from the cooling systems needed.
HELLADS makes use of a unique cooling technique to save weight. The high-energy laser uses a liquid that has the same angle of refraction as the mirrors inside the blaster. That way, the "ray gun" can fire away, even while it's being cooled. Currently in the third of five phases of development, a 15 kilowatt subscale prototype is being tested in the laboratory. In the next phase, the demonstrator device will be scaled up to 150 kW, and will specifically be targeted to achieve the low specific weight (5 kg/kW) and compact size need to be mounted in a smaller airborne vehicle. The final phase is engineering, fabricating, integrating and demonstrating the complete HELLADS weapon system on a tactical platform. The device will be built by General Atomics and the tracking system will be built by Lockheed.
This kind of compact system is getting very close to what science fiction writers since H.G. Wells have envisioned when writing about the heat ray in War of the Worlds. More recently, Larry Niven and Jerry Pournelle wrote about laser cannon in their 1974 novel Mote in God's Eye:
..."The intruder came from here. Whoever launched it fired a laser cannon, or a set of laser cannon - probably a whole mess of them on asteroids, with mirrors to focus them - for about forty-five years, so the intruder would have a beam to travel on... (Read more about laser cannon)
Read more at MTHEL, Playing with Liquid Fire: High Energy Lasers Cool Down, HELLADS (at DARPA).
So, is there even such thing as "secret" any more?
I'd give it more credence if they could get the terminology correct. I believe it's "index of refraction". The angle of refraction is the result of light passing from a medium of one refractive index into a medium of another refractive index.
I want to see it's first "real war" test on an insurgent ... and televised live from Fox News.
"ALAH AKBAR!!!"
ZZZZZZZZZZAP!
Why don't we use laser's for missile defense on ships and cities? I would think applying the technology to those areas would be a lot easier than trying to mount it on an airplane.
Lord Vader will be most please!!!!
I've got one of these in my yard down by the lake...
I think Val Kilmer figured this out a long time before DARPA did. Ice is nice.
"We needs bigger cannons!" "Shut up!"
The birthday present was really nice, but Christmas is just around the corner (hint, hint)!
'General Atomics'???
What a great name for a company building Laser Weaponry.
Sounds like something you would read in Marvel comics!
HELLADS primary technology advance has nothing to do with the index of refraction of the mirrors and the liquid.
Atmospheric absorbtion/refraction limiting the effective range? I'm guessing that these laser systems are strictly last-ditch point defense systems (THEL) or are mobile systems designed to nail a rocket early in it's boost-phase. There is talk that the F-35 will eventually mount a laser weapon. Evidently its engines, designed to power the shaft-driven lift fans, have enough surplus energy to power the laser.
I know we had operational laser weapon systems back in the late 1980s .....
I know that too...;-)
I'd be very interested to know what fluid they would use and how closely they need to match the refractive index. I also wonder how many times the laser can fire before photodegradation of the cooling fluid would require it to be flushed and replaced. It is a very clever idea for cooling a laser system.
Because mounting it on an airplane solves the problem of running out of ammunition. While the movies show aircraft blasting away with chainguns for minutes at a time, the truth is that ammunition tends to be heavy and aircraft go through it very quickly. Most aircraft, especially fighters, only have a few seconds of ammo.
Also, consider that you don't have to lead the target anymore and he can't evade your fire.
"That thing's operational!"
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