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Laser Cannons Coming to an F-16 Near You
dxprog writes "Reuters is reporting that the US Pentagon is designing a laser cannon that's small enough to fit onto a fighter jet yet powerful enough to knock out a missile. "The High Energy Laser Area Defense System (HELLADS), being designed by the Pentagon's central research and development agency, will weigh just 750 kg (1,650 lb) and measures the size of a large fridge." Now all we need to do is make fighter jets space worthy for that true Star Wars feel."
Will there be friggin sharks on them too?
4 out of 5 swinging dicks recommend more steel plates for their humvees, not another toy for the flyboys.
I just did some quick searching and found only this on laser weaponry in the Geneva Convention:
"Protocol IV on Blinding Laser Weapons prohibits the use of laser weapons specifically designed to cause permanent blindness to the naked eye (or to the eye with corrective eyesight devices). Countries that are party to the Convention and Protocols will not transfer such weapons to any country or other entity."
So I guess to conform to the Geneva Convention, the lasers will just require the same stickers that they put on childrens water guns: "Point Away From Face"
"0101100101? It's just jibberish. *looks in mirror, gasps* 1010011010@!? AHHHHHH!!"
source http://www.newscientist.com/article.ns?id=dn2585
"He is no fool who gives what he cannot keep in order to gain what he cannot lose."
Pew pew or Brzzap?
I'm too close for lasers, switching to Scientology.
Hello Mr. Enemy Pilot, may I Audit you?
"It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
and measures the size of a large fridge. Cool! Lasers have been used for measurement before, but I bet this is the first time the military has been able to measure your fridge in your kitchen from 20,000 feet. The small hole in the kitchen ceiling is a small price to pay for this protection from oversize fridges.
Very doubtful. ...)
The f 16 will be above of >90% of the athmosphere at the ceiling hight, so absorbtion in the atmosphere isnt that big of a problem. But divergence is.
No matter what movies will make you believe, lasers arent perfectly parallel beams of light.
Not to go too much into the details, a laser needs to have a large diameter to have a low divergence (hence the used large telecopes for the moon reflection experiments: a 5m laser diameter here will be a few km on the moon, wile a few mm here will be 100s of km there
I cant see how a jet-fighter mounted version would fullfill the requirements. The lens crossection has to be small enough not to fuck up the aerodynamics of the supersonic plane, and you cant just put a streamlines glasshood in front of hit because of the high pulse energies...
So you could get some light onto a satellite, but not enough to knock it out...
Otoh, I think it could be strong enough to permanently blind the CCDs of enemy spy-sats...
HI O WISE PRINCE. WHT TOOK U SO DAM LONG?
Yes one must be fucking living to be blind. Just like telling no tales, the dead don't see shit..
Do you actually have some evidence to back that claim up? I thought not. The people who come up with ideas like military lasers are actually smart enough to have thought of things like mirrored surfaces on enemy missiles. They wouldn't have put all that time, effort, and money into the project if it could be stopped by such a simple countermeasure.
Common mirrors are not 100% efficient; they absorb some fraction of the light rather than reflecting it. The actual reflecting layer is also quite thin. The small amount of absorbance is enough that a high energy laser will destroy an ordinary mirror very quickly, at which point the remaining energy is absorbed efficiently. The kind of extremely efficient mirrors needed for ultra-high power lasers are fantastically expensive and fragile enough that it's hopelessly impractical to try putting one on military gear.
There's no point in questioning authority if you aren't going to listen to the answers.
FYI this is NOT a liquid laser. The term "liquid laser" is barely ever used in laser research and when it is, its used to referr to DYE lasers which are absolutely not what is being discussed here. It could concievably be used to describe a chemical laser where the chemicals are liquid before being reacted to lase but this would be incorrect because lasers are typically classified based on the phase of the medium which undergoes lasing. In the case of the chemical laser the lasing medium is a plasma formed in a reaction chamber by the mixed, previously liquid, chemicals. It's a gas laser. From what I can tell here though, neither of these things is what is being proposed for the HELLADS system. It looks like what they're trying to do is match the index of refraction of a cooling liquid to the index of refraction of the slabs of lasing material in a SOLID STATE laser such as Nd:glass. Thereby allowing the efficient removal of heat from the laser material while it is firing and while also preserving the quality of the beam. I would be willing to bet they are looking at using ytterbium-doped strontium fluoroapatite (Yb:S-FAP) slabs immersed in a very dense transparent flowing liquid (perhaps even a molten salt like NaNO3) which is optically pumped by specifically tuned solid state diode lasers.
- "Hear that?! The percolations are imminent! Cease your ingress!"
150 kilowatts is 201 horsepower. (conversion link; 1 horsepower = approximately 745.7 watts)
F-16 Aircraft use a powerplant ranging from 15,000 to 19,000 (28,000 to 32,000 with afterburner) pounds force of thrust.
To convert between thrust and horsepower, use this formula: [(Thrust in lbs x Speed in mph) / 550] x 1.47 = horsepower (formula link)
So let's assume an airspeed of 400 miles per hour.
Without afterburners:
Low: ((15,000 * 400) / 550) * 1.47 = 16,036.3636
High: ((19,000 * 400) / 550) * 1.47 = 20,312.7273
And with afterburners:
Low: ((28,000 * 400) / 550) * 1.47 = 29,934.5455
High: ((32,000 * 400) / 550) * 1.47 = 34,210.9091
So let's say about 18,000 horsepower on average regularly and 32,000 horsepower on average with afterburners.
A 150 kilowatt laser requires 1.1% of the total engine power produced (on average) by an F-16 turbofan engine, and 0.6% of the engine's power with afterburners engaged.
In other words, I think they've got all the power they need.
Reinvent the wheel only at either a lower cost, greater effectiveness, or your own personal enrichment and satisfaction.
I went to U.S. Airforce Space Readiness Briefing while I was a Congressional intern this summer.
Lasers were covered and I had a brief chat with the Air Force representative after the briefing.
The USAF is sticking lasers in 747's and the army is testing ground-based systems.
The aircraft-based lasers cannot inflict any physical damage. They are powerful enough to scramble electronics. The goal is to target a missile shortly after it is launched so that its guidance systems fail and the missile lands in the enemy's territory, never reaching its target (us). Their goal is to use this as a powerful deterrent by making it very risky to launch missiles.
The ground-based systems can inflict physical damage, but are nowhere close to being airborne (they're much too massive). They are, as I was told in July, still "in the lab." (I later saw a full-page ad in "The Hill," a capitol hill newspaper, promoting Lockheed Martin's ground-based laser systems as though they were about ready. I'll trust the USAF officer's discussion more than the corporate advertisement.)
A key misunderstanding of lasers is in the kind of damage they inflict. Lasers will poke holes through objects but do not cause a target's destruction or explosion -- however, shooting through or over-heating a target's fuel tank will cause an explosion. And of course, to re-emphasize my major point, we don't have airborne laser cannons --- their goal is basically to inflict a kind of EMP-like damage to missiles. I asked about getting these things into UAV's and was told they'd love to do it, but don't expect anything for another 50 years.