67-Kilowatt Laser Unveiled 395
s31523 writes "Lawrence Livermore National Laboratory in California has announced they have working in the lab a Solid State Heat Capacity Laser that averages 67 kW. It is being developed for the military. The chief scientist Dr. Yamamoto is quoted: 'I know of no other solid state laser that has achieved 67 kW of average output power.' Although many lasers have peaked at higher capacities, getting the average sustained power to remain high is the tricky part. The article says that hitting the 100-kW level, at which point it would become interesting as a battlefield weapon, could be less than a year away."
Re:Yanks developing more weapons (Score:2, Informative)
In fact, 25 nations spend a higher percent of their GDP on the militairy than the US does.
Just look at how the military didn't lift a finger to stop 9/11, even though they had precise warnings from multiple credible sources.
Really? Where did you read this? I thought it was a big conspiracy by the tin foil companies.
Re:May cause som collateral damage (Score:5, Informative)
Re:two things (Score:3, Informative)
Industrial uses of high-powered lasers include laser cutting and welding. I don't have any experience with either one, but I imagine they could benefit from power increases (cut thicker parts faster) and solid state (hopefully means cheaper and lower maintenance).
Laser-thermal rockets are also not that far away from reality; what they lack is a fair bit of development effort, currently hindered by the cost of high power continuous output lasers. The basic way they work is a high power laser on the ground aimed at a heat exchanger on the rocket that heats hydrogen (the best working gas) to very high temperatures (relatively... 2-3000 kelvin is enough to be interesting with hydrogen) and exhaust it, developing several times the specific impulse of conventional chemical rockets. The advantages are lowered cost if you have a high flight rate -- you can use the expensive bits for many many launches per day, realistically limited only by how fast you can get new boosters into position. And yes, the math suggests you can do single stage to orbit (depends on the details of your heat exchanger performance, obviously). And, they're absurdly power-hungry -- one newton of thrust requires ~ 5kW of laser power; even a demonstration rocket would likely need hundreds of kilowatts or more of power.
Re:It will vaporize your head... Unless... (Score:5, Informative)
If your mirror is 99% reflective (which would be very, very good -- and it won't stay that way in a dusty dirty battlefield), you'd still be absorbing 1kW of power. Which might be very easy or very hard to dissipate, depending on the beam diameter and how well the targeting system can keep it on the same piece of armor. And, as soon as your armor starts to heat up more than a little, the reflectivity will drop and it will fail.
Everyone always thinks mirrors are an easy answer to laser weapons, but it's not really that simple; sure they're worth considering, but they're not obviously a winning strategy.
A better armor might actually be an ablative -- eg a phenolic or graphite plate that absorbs all the heat at the very surface, and vaporizes into a cloud of gas that then takes the majority of the heating while the armor continues ablating from conducted heat and laser heating that gets through -- meanwhile the targeting system frantically tries to keep the laser on the same spot long enough to punch all the way through, and the tank driver tries to conduct evasive action. Modern ablative technology for rocket engines can take 1kW/cm^2 of heating and last for minutes of service; ablatives derived from such technologies might make very effective armors.
Re:Yanks developing more weapons (Score:3, Informative)
Name one, and explain how it's more free (not "a better place to live" or "more friendly to the environment").
Problem is, US citizens don't live in a democracy, so can't affect the foreign policy of their ruling class. Think I'm wrong? Think again. They just voted out the Republicans in an absolute landslide which is largely recognised as being a rejection of Republican foreign policy, but you watch just how much that policy changes, both now AND when they get rid of Emperor Dubya.
Psst. We Americans have this thing called "Federalism", which intentionally limits the ability of any one election to dramatically shift the nation's course. 2006 was a mid-term election, meaning that only 4/12 of the democratically-elected national government were subject to voter approval -- after a twelve-year tilt towards our President's party. Federalism was designed to slow dramatic changes, like a sudden shift in policy when twelve years of a party's dominance end.
2008 is when the American Democratic System will be more flexible, when a full 10/12 of the national government will be up for voter approval, and 6/12 of our government is going to leave office by law. (There's still 1/3 of the national government that is going to be influenced by the current administration after 2008, as the judiciary is not democratically elected, but rather appointed to mostly lifetime terms by the other two branches.)
If you don't think that common Americans can change public policy -- well, it's black history month, and you should spend some time reading up on things like the Civil Rights movement, the beginning and end of Prohibition, or just the 1994 "Republican Revolution" that started our nation on its current path.
(We COULD have gone with a directly-elected parliamentary system, but we much rather like having something to moderate our public policy when we have such strong and ardent divisions as to how our country should go. Y'know, 'cause we're democratic.)
Need: Sharks, duct tape (Score:5, Informative)
The Air Force has a real hard on for laser systems. Though it doesn't say specifically in the article it appears this lab was awarded the AFRL's contract to produce a solid state equivalent to the ATL system being developed largely by Boeing. The ATL is a smaller cousin of the ABL weighing in at about 70kW. It's an order of magnitude lower power than the roughly 1MW ABL but is also quite a bit smaller. The ABL requires a 747, the ATL is being developed to be mounted on a C-130 or V-22 Osprey. A solid state ATL would be far more useful for the Air Force than a chemical one. A solid state laser system on an aircraft could be powered by generators hooked to the engines and fired an indefinite number of times in flight.
Nerd pack upgrade! (Score:2, Informative)
Time to update your laser pointers! The old ones only melt plastic, light matches and pop balloons. [wickedlasers.com]
(Have to be ready for when the sharks attack--and they will!)Re:two things (Score:5, Informative)
The satellite-based lasers for Star Wars (Reagan's wet dream, not the Movie) primarily worked by kinetic activity.
A cutting laser doesn't take anywhere near 67kW, but they work fairly slowly (slow enough for an armored target to take countermeasures). Instead, you want to basically vaporize a few nm of the surface, resulting in exactly the sort of explosion you say doesn't happen.
Search Google for "arc flash"... Though a much more mundane effect, it gives the general idea... Basically, if you vaporize copper bus bar by shorting it out, it produces a pretty impressive "explosion" due to the copper suddenly occupying 67,000 (no connection to the laser from the FP, just a coincidence) times its original volume.
Re:Yanks developing more weapons (Score:4, Informative)
China? Sorry, the US military budgets dwarfs them incredibly. The official US military budget accounts for 50% of the world's military budget. So they are outclassing you, but not in the way that you mean.
Re:Obligatory (Score:3, Informative)
Actually, not Korean soviets as such, but those of the USSR type were not unknown during the Korean war (or 'police action'). Many UN/Allied aircraft were lost during the Korean war to Soviet fighter pilots. See here for some info: http://aeroweb.lucia.it/rap/RAFAQ/SovietAces.html [lucia.it]
I recall from my youth, I had opportunity to listen to one of my fathers' buddies that had flown an F86 Sabre in combat during the war. I remember him saying that they could quickly tell if the enemy pilot they faced were Soviet or Korean by the way the more inexperienced and poorly-trained Korean pilots handled their aircraft, as opposed to the highly-trained, experienced, and confident Soviet pilots.
He said they knew that if the pilots they faced were Soviet, chances were very good that he or one of his buddies was about to die, so determining which they faced as soon as possible was a high priority.
Cheers!
Strat
I checked... (Score:2, Informative)
I checked, [wikipedia.org] you apparently did not. China is second on the list, at about 1/8 of the USA.
Just note, the US official military budget is over 18% of china's GDP. There is no way that china outspends the US.
T
Re:Oh, please (Score:3, Informative)
I've been hearing this addage, fairly frequently, for 30+ years. But in it's *actual* classic form, which is pretty much as you originally posted it, not with the 'with each others' qualifier you've just added. In which form I have *never* heard it, until now. So if you actually thought "everyone had heard about it by now" in it's qualified form, you are very much mistaken.
For instance, you might read Bernard Lewis at:
http://www.princeton.edu/~paw/archive_new/PAW02-0
It's somewhat apropos of my post, informative material by a guy widely judged to be rather thoughtful, and contains the addage in question.
I strongly suspect that anyone who can use a search engine will find many more references to this adage without your revisionist qualifier than with it.