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More on JSF Laser System
An anonymous reader writes "Seems Lockheed Martin has won a contract to equip future versions of the Joint Strike Fighter with a 100-kW laser. Housed in a dome within the aircraft, the laser's turret would emerge for firing [sound familiar?], and the laser itself is spec'ed to achieve airborne and ground kills at a distance of more than six miles. The problem? According to this Aviation Week article, Lockheed Martin has to figure out how to dissipate 900 kilowatts of heat. Maybe the Finnish airforce could value-add to the OEM model." We mentioned this earlier.
the plot of Real Genius than a star trek episode...
std::disclaimer<std::legalese> sig=new std::disclaimer; sig->dump(); delete sig;
900Kw of heat, and only a 100Kw laser? Wow, not to effcient is it?
Very efficient for a laser. Most lasers get less than 1%.
If you don't understand any of my sayings, come to me in private and I shall take you in my German mouth.
They can use whatever heatsink comes out for those 4 Ghz Pentiums...
bytesmythe
Hypocrisy is the resin that holds the plywood of society together.
-- Scott Meyer
if they are gonna put a huge warning sticker on the front of the figher: "Do not stare directly into laser"?
I Am My Own Worst Enemy
I can see it now:
GI: Sarge! There's a dozen or more enemy troops on the other side of that ridge! I'm going to call for air support: They'll blind those bastards with a laser! We can go in and round 'em up.
Sarge: No can do, soldier. That's against the Geneva convention. You tell your flyboy buddy to drop a Daisy Cutter on those a-holes. I'm afraid the only humane way to handle this situation is to incinerate those poor bastards to a crispy crunch.
GI:Yes, Sir!
It used a hydrocarbon fuel not very different from kerosene.
Very different from kerosene. Most military jet aircraft run on JP-5 or JP-8, which are essentially aviation kerosenes.
The SR-71 runs on JP-7. JP-7 is a more viscous fuel with a low vapor pressure and a very high flashpoint. So high, in fact, that the SR-71 can't start its own engines. To light the fires on a Blackbird takes a chemical ignition system, where the ground crew squirts a measure of tetraethylborane into the engines. TEB is actually hypergolic with JP-7, and the resultant explosion starts the engines.
The airframe heats up to 1000 degrees F in high mach flight, and so it has to be built to fit together nice at the higher temperature. When it's on the ground and cool, it does indeed leak fuel like a sieve. And yes, they do pump fuel from tank to tank in flight to cool hot spots.
Dear lord, what a plane. 5.2 thrust-to-weight ratio. 3200km/h. 85,000 ft ceiling. 1100 C inlet temperatures. 2000 degree combustion exhaust. Has successfully evaded over 4,000 SAMs.
Like, wow.
I work in a laser lab, were the laser we work with (an Argon Ion) puts out a maximum 15 watts of power (of multiple wavelengths of visible light) in a ~5mm diameter beam.
At 1/2 watt, it will blind you immediately if your eye passes in front of it.
At 3 watts, it will burn through a piece of paper.
At 6 watts, it's burning through my sleeve.
At 8 watts if I accidentally wave my hand through it, it will cause blisters to form several minutes later.
At 10 watts, our power meter starts smoking and our mirrors begin to get these ugly burn marks on them.
At 15 watts, it'll burn through an aluminum can.
This is for a continuous wave laser (one that doesn't pulse). Now you can imagine what 100,000 watts will do:). The question is, seeing as how this must be firing in pulses, what is the pulse length? Minutes? Seconds? Milliseconds?
I'm also curious what wavelength it is firing at. I didn't notice it in the article (but I definitely could have missed it). Anyway, I hope that helped answer your question. Maybe some other slashdotters out there have worked with more powerful lasers?
JoeRobe
The best way to predict the future is to invent it.
For some people, this is an acceptable way to relate to other people. If you don't like other people, just kill them. Preferably from a long way away.
It's profitable, too, for a small number of people, because the weapons are secret and therefore the profits can be kept secret.
It's an adult video game. Except that you don't get to play. You, if you are an American taxpayer, only get to pay.
There are a lot of people who would like to kill other people if it is free and they don't have to go to prison. It's a kind of mental illness. For more about this, see What should be the Response to Violence?
Violence tends to cause other violence. Mostly hidden elements of the U.S. government are causing the U.S. to be a target of violence. For example, the U.S. government (taxpayers) spend more than $900 every year for every man, woman, and child in Israel so that Israelis can buy U.S.-made weapons to kill Arabs. It's a way of transferring money from the taxpayers to the weapons makers. It seems likely that this will result in another holocaust; I doubt the Arabs are kidding when they say they will never surrender.
Every day in the U.S., it is possible to see American leaders on television calmly discussing the killing of other people. Of course, they have come to believe that they will never be the target.
I accidentally posted this anonymously before, so here it is now, with my name on it.