DARPA Developing Defensive Plasma Shield 318
galactic_grub writes "According to an article at New Scientist, DARPA is developing a plasma shield that would allow troops to stun and disorientate enemies. The system will use a technology known as dynamic pulse detonation (DPD), which involves producing a ball of plasma with an intense laser pulse, and then a supersonic shockwave within the plasma using another pulse. The result is a gigantic flash and a loud bang in a the air. 'The company has also pitched a portable laser rifle, which would be lethal, to the US Army. It would weigh about fifteen kilograms, would have a range of more than a mile, and could have numerous advantages over existing rifles - better accuracy and the ability to hit a moving target at the speed of light.'"
Lasers efficient at killing? (Score:5, Interesting)
Dan East
Also, FTA... (Score:3, Interesting)
Wow. Just Wow. (Score:2, Interesting)
I don't know about others, but this sounds pretty much like stuff we could read about in comics and watch in cartoons. Wouldn't it be funny if somewhere in a small well-guarded room there's a top-notch team of physicists that does research on new weapons by reading comics?
Re:Laser rifle (Score:3, Interesting)
Re:Laser rifle (Score:4, Interesting)
33kg is not a light weapon, and not something a sniper could simply hold up for precision firing with his hands. You would probably need a tripod, etc. So in the end you are looking at a not-very-sniper-like weapon.
Re:Lasers efficient at killing? (Score:3, Interesting)
Re:Laser rifle (Score:5, Interesting)
Actually, this would be a win from that standpoint as well. Current sniper bullets are always supersonic, and thus there is a loud *CRACK* sound that helps indicate the location of the sniper. The laser beam would be silent.
(If you are interested in snipers, you ought to read the book Marine Sniper [amazon.com], a biography of Carlos Hathcock [wikipedia.org]. Hathcock commented that a sniper usually gets one free shot, because no one is expecting the shot, and surprised people don't do a good job of figuring out where the shot came from; if the sniper fires a second shot, all the people in the area will start looking in the correct direction, because this time they are expecting something. So he figured it was better to get close enough to get a guaranteed one-shot kill; even though he would be closer, he would be much harder to find than if he had to take a second shot.)
Imagine a sniper killing someone, and the only sound is the body falling over. Kind of creepy. The sniper might be able to kill the person without other people in the area even noticing!
On the other hand, assuming a high-tech enemy, it might be possible to track the sniper by waste heat from the laser. If you are putting enough energy to kill out of a laser rifle, there will be nontrivial amounts of waste heat. So there might be a special "sniper model" battlefield laser weapon that contains the heat somehow (cartridges with compressed gases, and you use the expanding gas to cancel the waste heat?). Thus the sniper model would probably be the heaviest model.
(Or perhaps the heaviest model would be the "squad automatic" laser, which could be fired many times rapidly...)
Actually, a physics question: would there be a trail in the air, caused by the laser traveling through the air, that could be seen with some sort of vision enhancer goggles? Would the air molecules be ionized or something, and could that be used to track a sniper? If so, there would be a line drawn in the air pointing from the target straight back at the sniper. But I really have no idea if that is possible.
steveha
Non-lethal application (Score:3, Interesting)
Basically, if you can ionize the air, you should have a conductive path. You could then send a high-voltage current down that path to incapacitate the person struck.
Re:I'd better get one, too (Score:3, Interesting)
If governments wanted the people to have power (utlimately all power is derived from force) our rebel leader forefathers wouldn't have had to put the right to bear arms in the constitution. It exists precisely because power must be distributed and a disarmed citizenry only have power at the mercy of the government.
Re:Why the toys??? (Score:5, Interesting)
Besides, accuracy at a great distance usually means nothing in city warfare. You almost never have ranges larger than 15-20 meters and AK-47 works great at these distances.
Re:Lasers efficient at killing? (Score:4, Interesting)
Re:Why the toys??? (Score:3, Interesting)
Re:Why the toys??? (Score:5, Interesting)
Now the question is, when can we afford to use troops in the following situtations:
1. Limited, humane "war". Oxymoron if their ever was one. Usually a failure, re: Vietnam.
2. Geneva Convention "war". Works pretty well. Won in WWII and Korea.
3. Total war. Pre-Convention war, no quarter given, civilization at risk. This is the long history of warfare and is true war.
We are fighting an enemy using level 3 warfare while we remain at level 1.
Level one is total stupidity. If that is all that was needed, you should have used other means like special forces hit and run. Don't send in long term troops unless you are ready to fight level 2.
So go to level 2, or get out and wait for them to sack Washington.
The scary thing for me is that as they get nukes, and they will one way or another, there is no way to do MAD style containment. They are not going to launch anything at us because they don't have the technology. So they sneak it in and detonate. Meanwhile, because we are so hung up on national boundries they don't really recognize, we don't know who to nuke.
And we lost our ablity to fight as a civilization, like Rome, and just nuke the barbarians, period.
I really don't see a way out until we shake out of our lethergy and understand that they want us all dead or converted to Islam. Anything else is al-Taqiyya.
Re:"Money well spent" (Score:2, Interesting)
Do you have any facts to base up your assertions? Where are the surveys done by, say, neutral countries that suggest what you are saying is true? I'm assuming you are not being sarcastic.
The US is notorious for supporting dictatorships and coup d'etas against democratically elected governments. Consider Honduras for instance, when the CIA supported a coup at the behest of the United Fruit and Standard Fruit companies. The US basically blockaded Fiji because they wouldn't allow for the testing of nuclear bombs near their shores. We've had heavy involvement in Iran for many years. Oh, and the support for Pol Pot?
Anyone who says that envy drives the hatred of America is woefully ignorant of American foreign policy.
Re:Laser rifle (Score:2, Interesting)
Re:Why the toys??? (Score:3, Interesting)
This is gonna sound silly (Score:5, Interesting)
And, well, I had to admit there was a point there. Maybe we should find it disturbing that so much research is being put into this kind of thing.
Re:Laser rifle (Score:3, Interesting)
Crossed my mind too, as several posters mentioned ionization of air along the beam: instead of relying on conversion of stored charge into current, then into light, to deliver destructive energy on target, just create an ionized channel and pour all the stored charge down on target. The show stopper is, of course, a possible "short circuit" discharge between channel and ground anywhere along the beam path, which, due to limited minimal angle between the beam and surface limits applicability to air-to-ground use.
Vice versa, anti-sniper measure would be to keep possible target of assassination inside an isolated Faraday cage connected to powerful high voltage source - if high-power laser was deployed, assassin sniper would have been zapped through the channel his weapon created.
However, there seems to be another, to me much more interesting possibility, completely out of military and destructive applications: the whole idea could be used to construct a laser induced conductive ionized air channel "infinite hight lightning rod", a system to harvest huge atmospheric electric energy in controlled manner, for our power needs!
Or, perhaps those ionized channels could be used for very low current, very high voltage electrical power transmission without using metallic conductors at all. Perhaps we could even connect surface-to-orbit spacecrafts with ion engines to electric power grid using that technique, one "conducting channel" on each side of spacecraft, so that very little fuel mass is lifted.