Friday, January 21, 2011

Sharks with Lasers




"You know, I have one simple request. And that is to have sharks with frickin' laser beams attached to their heads! Now evidently my cycloptic colleague informs me that that can't be done. Can you remind me what I pay you people for? Honestly, throw me a bone here." — Dr. Evil (from Austin Powers: International Man of Mystery)



Lasers. Occasionally misspelled "lazer" in fiction. Actually the name "L.A.S.E.R." is an acronym of "Light Amplification by Stimulated Emission of Radiation", since that's what lasers do.

The majority of us learned about lasers from TV. Laser weapons and Hollywood. Laser weapons on TV hit high on the cool scale but how real is it? Remember, Hollywood science rules and the energy weapons depicted usually move at the speed of light. In actuality, energy weapons move a lot slower than the speed of light (and sometimes slower than the bullets on the same show). The Hollywood ones can also be dodged. You're seen it, our hero sees the person aiming the ray gun at them and going for the trigger in in that split second he's able to hide behind a rock or whatever. If the bad guy is hit, he is instantly zapped and vaporized. If the good guy is hit, he just stumbles back a few feet. There were all kinds of such weapons in the movies. Retro ray gun was the death ray. Real handguns bowdlerized into energy guns were TV's version of space age family friendly firearms. A lot of it was simply made up, a lot of it was technology even now, terribly outdated.


But TV physics is TV physics. There's a common misconception that laser beams cauterize wounds, but trust me, real laser wounds are every bit as ugly and bloody as knife wounds. Heat from a laser only makes a tiny bloodless hole on TV. NOT. In reality, it can cause the water in the body to boil, expand and rip the surrounding tissues apart, mimicking the injury from high velocity bullet impact.

Energy weapons in fiction will always have knockback (which would be OK) and recoil (which makes absolutely no sense at all), in spite of the fact that energy has negligible momentum. Of course, no matter what the laser's frequency and the medium through which it is shooting, it WILL make loud futuristic ZAP noises. But laser weapons on TV aren't a realistic depiction of how real energy based weapons would work, they're not intended to be. They are stand in's for some real guns to appease the liberal producers or more often to simply establish the show as being sci fi (and thereby higher up on the cool scale). If you look at some of the very early futuristic TV and movies, the laser bolt effects looks a lot like machine gun fire using tracer bullets. This may be that many of the artists and engineers that worked on the earliest of such films have have been relating their own war experiences in inspiring that effect, many having served in WWII.

Some later shows confused lasers weapons with plasma weapons, which fire really hot gas, not light beams.. Necessarily, plasma weapons can't use light speed projectiles as, having mass, they would be susceptible to all sorts of physics that make approaching the speed of light extremely difficult.


Plasma weapons are almost always depicted as producing ludicrous (usually green) glowing puffballs that somehow avoid mixing into the air, sometimes hand waved as magically auto generated magnetic containment. An actual plasma weapon might be as useful as a gun that shoots steam; sort of like your very own flamethrower, only hotter.

Laser weapons are here, and they're being continually refined. One of the first known to the civilian science geek was the Airborne Laser and THEL. The Boeing YAL-1 Airborne Laser Testbed, (formerly Airborne Laser) weapons system is a megawatt-class chemical oxygen iodine laser (COIL) mounted inside a modified Boeing 747-400F. Designed primarily as a missile defense system to destroy tactical ballistic missiles (TBMs) while in boost phase, the YAL-1 with a low-power laser was test-fired in flight, at an airborne target in 2007. A high-energy laser was used to intercept a test target in January 2010, and the following month, successfully destroyed two test missiles. (1)
It's pretty impressive. The COIL, is comprised of six interconnected modules, each as large as an SUV turned on-end and weighing about 6,500 pounds. When fired, the laser produces enough energy in a five-second burst to power a typical American household for more than an hour. (2)

The cooperative Tactical High Energy Laser (THEL) Demonstrator ACTD was initiated by a MOU between the US and the Government of Israel in 1996. The THEL is a high-energy laser weapon system that uses proven laser beam generation technologies, proven beam- pointing technologies, and existing sensors and communication networks to enhance active defense capability in counter air missions.

The joint program was initiated to develop a THEL demonstrator using deuterium fluoride chemical laser technologies. THEL uses a Deuterium-Fluoride (DF) laser. NF3 and C2H4 are first reacted in multiple, side-by-side, high-pressure combustion chambers using an oxidizer (NF3) rich mixture that generates free F atoms. After ignition the combustion-generated F atoms, mixed with combustion by-products and a He diluent, flow into the laser cavity. A mixture of He and deuterium is also injected into the laser cavity, and DF is generated in an excited state as deuterium reacts with the free F atoms. The laser cavity is now ready to produce a laser beam.

Can I say "awesome" without sounding like a nerd?

THEL uses both Hydrogen Peroxide and Nitrogen Trifluoride. Nitrogen Triflouride (NF3) NF3 is used as a fluorine source in high-energy chemical lasers. Two applications are THEL and MIRACL (Mid-Infrared Advanced Chemical Laser) at White Sands Missile Range. Type 70 Hydrogen Peroxide is a critical element in the Anti-Ballistic Laser (ABL) and THEL Programs. Chemical lasers are the only class of HEL able to achieve megawatt power levels at century's turn. The MIRACL is a deuterium fluoride (DF) laser operating at a wavelength of 3.8 microns that has been in operation at the megawatt level since the mid 1980s at the White Sands HEL Systems Test Facility. It suffered from inherent propagation losses at full power in the operational wavelengths. DF technology found a home in the US Army/Israeli THEL, where propagation losses were mitigated by lower power levels and a crossing target.

Lasers - Deadlier, cooler.
Then, there is DARPA's HELLADS (High Energy Liquid Laser Area Defense System), light enough to fit on a fighter jet or drone aircraft, yet powerful enough to fire a 150 kilowatt beam of energy.

The Star Wars laser cannon may be closer than we think.

There have been high energy laser weapons in development powerful enough to bring down missiles (i.e MEHEL Mobile Tactical High Energy Laser). However their sheer size and weight (from the cooling systems needed) has precluded placement on just the largest aircraft.


HELLADS has a unique cooling system 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 development, the demonstrator device will be tested and scaled to achieve the low weight specifics and size needed for smaller airborne vehicles. Then the final phase of engineering, fabricating, integrating and demonstrating the complete HELLADS weapon system on a tactical platform. (3)
This sort of compact system is getting very close to what science fiction writers since H.G. Wells have envisioned when writing about the heat rays. 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... "

Solid-state pulsed lasers, which fire bursts of energy and which are lighter than fluid-based lasers, but harder to cool, and electrolasers which ionize the air so that electric current can be sent along the beam's path, are already in development. More science than we ever saw watching Star Trek as children.

In actuality, these characteristics make lasers far more effective, and terrifying as weapons than anything we see in TV or movies, sharks not withstanding. It's probably also why we're not seeing realistic laser weapons in children's shows ("I love you, you love me. ZAP !!")

Since I won't get to play with any of these such toys, I'll happily embrace laser technology as I need and can obtain to protect my world. Viridian makes one of the better laser sights on the market, hands down, and they have their new catalog out.

Why green? The guys on TV got that part right. Green is much brighter and more effective than red in most conditions. Ordinary red lasers can be next to impossible to see in most daylight conditions. The benefit of a green laser is that it is much more visible, allowing for it to be used anytime, day or night, indoors or outdoors, permitting the LEO or civilian defense or sport shooter to track the target point quicker and more accurately. Additionally, because green lasers are so much more visible to the human eye, you can actually see a very intimidating visible beam in low-light conditions.
Nothing knocks the fight out of bad guys like the sudden appearance of a C5 equipped sub-compact. The brilliant green laser says “don’t mess with me", 24 hours a day.

For may not have to worry about storm troopers but I do have to worry about home invasions, muggers and murders. I'll take the best technology out there, and craft it for my use.

1) DoD 4120.15-L, Model Designation of Military Aerospace Vehicles. U.S. Department of Defense, May 12, 2004. (2) Grill, Tech. Sgt. Eric M. "Airborne Laser fires tracking laser, hits target". Air Force, March 21, 2007.

20 comments:

Midwest Chick said...

Just for you, Brigid:

http://www.youtube.com/watch?v=Pozlp_wnkRk&feature=related

Shannon said...

WOOOSH! Hear that? It was most of the first part of your post flying right over my head. No matter, that's why I have a nerdy friend like you...to explain these things to me! The Veridian, on the other hand, I fully comprehend. Love you Sis!

Joshkie said...

:-)

john bord said...

Kind of like the idea of trailing a small canon behind me jalopy. Wonder how the tailgates would enjoy looking down the barrel of a howitzer.

Have you read any of the stuff on the magnetic guns?

Now where is me lite lazer n star bucks.

John B said...

It's depressing that I have a nodding acquaintance with all of those articles, and I'm a dilettante. I have red lazers by the truck load, and a blue one that somehow survives. I just haven't yet made the financial jump to green.

(Trudges to eBay and Gunbroker)

Jim said...

No radiation like coherent radiation :-)

Jim

D.W. said...

After I read your post, I thought you might be interested in this:

http://www.foxnews.com/scitech/2011/01/20/raygun-breakthrough-revolutionize-naval-power/

This technology seems to be developing at an incredible pace. I remember doing some support for the ABL testing program back in the late 90's, and since then they've already had to cancel the program because the weapons have eclipsed that technology. Given another 20 years, we may all have commercially produced laser rifles in our closets. As long as they can shut down BATFE before then, of course...one can always dream.

Joshkie said...

Cartoon laws :-)

W.V. etruce.

what happens before isurender.

RC said...

Geek...(and I mean that in the loving kinda way...)

Brigid said...

RC - I was torn as a kid, couldn't decide whether I wanted to grow up to be a spy, mad scientist or cowboy.

Robert said...

Just saw a new laser item in the news a couple of days ago. It's about the Navy's future ship defense system utilizing the FEL (Free Electron Laser). Could be interesting for the techies among us.

Island Bob

Roscoe said...

The first thing I thought of when I saw the YAL test footage was "Real Genius".

Life imitated art bigtime that day. The only thing missing was a giant Jiffy Pop.

michael said...

I used to be a simulation operator (and SME) for some large military R&D events, as a contractor. (Who says NFO stands for No Future Outside?)

During one of these events the Air Force sent their model of the ABL to hook up and play in the event.

I asked the operators of the ABL model what would happen if the laser were fired at a combat aircraft.

They answered, 'Well... not that it would ever be used for that, but, in the first few milliseconds the cockpit windscreen would craze and turn opaque. Then, in the next few milliseconds, everything flammable in the cockpit... uh... including the pilot.... would ignite, then the fuel and weapons.'

So, on the Good-Bad Scale of Aviation, I think I am putting this down as, 'that would be bad'.

The first pilot to be shot down by laser isn't even going to know why or what happened. At least with missiles you have a chance at: , , , ECM and repeat. I guess when ground-to-air, and air-to-air lasers are ubiquitous, being a X-Box drone pilot will be comforting.

Answers? I don't know the questions. said...

Brigid,
I have a 25 second video on my blog that I think you would get a kick out of. You won't like the start but you'll love the ending. lol

Tango Juliet said...

And here I thought all the fuss over "green" lasers was out of concern for the environment.

The things I learn here!! :)

Joshkie said...

Micheal -

R&D and the military. We wouldn't deploy a weapon like that unless we had a counter. Almost every project has two tracks: weapons development & defense against said weapon. We just trying to stay ten steps a head of everyone.
Now I'm wondering what they would be? On to google.

Josh

Joshkie said...

Michael - FYI

http://www.wired.com/dangerroom/2008/07/spray-on-laser/

http://blogs.howstuffworks.com/2010/06/01/laser-proof/

Josh

Borepatch said...

Coolest physics experiment I did back at State U was repeating Michaelson-Morley, setting up lasers and rotating mirrors in the basement of the Physics Building (largest and darkest room available). Got within a couple percent of the value you read when you google "c".

But alas, it wasn't Death Ray lasers.

michael said...

@ Josh

Thank you for the link. I have not been in the SME/M&S world for a few years and have not kept up with LCM (Laser Counter Measures). Of course next is the LCCM, 1-up stage.

Joshkie said...

Sorry, Michael as I was reading my and your post to check where we where in the conversation.

"We wouldn't deploy a weapon like that unless we had a counter."

That sentance should of had a question mark, and the next part was suposed to be a clearfication of what my understanding of Military R&D is like.

I read what I wrote and was like what an arrogant prick... sigh, It is amazing what a question mark means to a sentance.

:-(
Josh