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FBI Investigating Laser Beams Pointed at Aircraft
sakshale writes "In an earlier discussion about Laser Pistols, many people argued about the concept of using them to target pilots of airliners. Apparently the FBI is investigating incidents in Cleveland and Colorado Springs. They issued a warning on December 14th."
Given some time, and--right or wrong--somebody will attempt to pile on the regulations and we can forget about buying green lasers from ThinkGeek or anyplace else.
Sigs cause cancer.
So fitting. I was blinded by the laser
-nB
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By sharks with frickin' laser beams on their heads...
500GB of disk, 5TB of transfer, $5.95/mo
Some good links from FreeRepublic.
Seems like Dr. Evil and his "laser beam" are finally starting to do their evil deeds!
Engineering and the Ultimate
More information in this article that may be helpful. I think this is potentially a very serious problem.
How can a laser beam travel round the nose of a plane overhead, and accurately reach the pilot's eyes from say, a few thousand feet away?
The guy pointing it must have steady hands, and damn good vision.
it has been mentioned and it is obviously required that the laser track the cockpit. exactly how has the technology to track the COCKPIT of an airliner moving 200+mph. (pilots mention a constant laser light for 10+ seconds)
tracking the plane is one thing, and even that is tough to do if you are talking laser accuracy, but the cockpit? also, this has to be done several miles out, since the cockpit windows don't have much downward view anyway.
outside of military technology, are there any commercial systems that could even do this?
Perhaps public misperception can eventually make lasers easier to obtain and more widely produced rather than regulated to the point of inaccessability.
1. People think the lasers are weapons.
2. Other people start selling lasers as weapons.
3. Weapons are constitutionally protected for civilian ownership in all civilized nations.
4. Ergo - the Lasers can be purchased at your local sporting-goods store after a background check and some paperwork.
(Author's note, Point #3 is intended to be a bit of a joke. But I expect at least one reader will not read all the way to this disclaimer, instead flaming me good and hard.)
Trying to use sarcasm in text-based forums does not work.
You'll take my green lasers when you pry them from my cold, dead fingers.
You can easily find computer operated 60w lasers. And yes its beam is 5 inches wide.
That would hurt.
I have no doubt this will prove about as fruitful as their investigation into Bonsai Kitten
Slashdot: News for Nerds, Stuff that matters only to them
This may or may not be a threat. Some interesting thoughts here
But it seems to be that it would be awful hard for something from the ground to actually hit the inside of the cockpit unless it had some sort of tracking device to track the plane, and was high enough to hit the inside of the cockpit instead of the nose cone (perhaps on a tall building or mountain near an airport).
I think this could be another tactic to strike fear into the populace.
Unfortunately, that's the idea.
- Totally seal the borders
- Confiscate and auction off the properties of all employers of illegal aliens to pay the expenses of
- sending illegals home
- back taxes and
- social service costs of supporting illegals to date
- provide huge prize incentives for commercial development of alternatives to the fragile air transportation infrastructure
- provide huge prize incentives for commercial development of small-capitalization self-sufficiency systems so that small communities if not individual households could provide their basic necessities without reliance on centralized structures
- tear down the prison system as unfit for human habitation and construct a new one in which none of
- make sure that when national guardsmen come home from Iraq, trained in urban warfare and all pissed off at having been abused by the government, they at least have a job.
I know, I know... This is all way too sane for the scum who have occupied the positions of trust and authority within the de facto government of the US.- prisoner rape or other violence
- hepatitis C or
- AIDS
was a substantial risk andSeastead this.
Green appears the brightest on the human spectrum. Most of these small lasers are DPSS (Diode pumped solid state). If the beam is coherent it is *INDEED* a danger, and nothing scares me more than the thought of hoodlums running around with 600mw "laser pointers".
Lasers for display are regulated by the Center for Disease and Radiological Health. Your not supposed to direct a laser above 5mw up into the sky.
At a long distance, the beam definitly becomes incoherent. Gas lasers are considered better than solid state in regards to beam colimation, and without optics my 2.5' long argon tube beam ends up 1' or more wide at a distance of only 1000 feet or so.
Targeting, no... Someone might manage to cross the planes path, but in order to track a plane I'd iamgine you would need to build a box filled with dirt sitting on innertubes to isolate vibration, then come up with a servo mechanism. I don't think 16 bit DACs would give enough accuracy with glavos.
Weapons targeting systems do not use visible lasers AFAIK. It would be a giveaway if there was a bright green dot on the target and a green line tracing back to the source.
Also, laser light is different then searchlights because the light is polarized. So you can see the beam better from one way versus the other.
Southeastern Virginia REPRESENT!
One night I was on a CAP SAR flight and we were targeted by such a laser. They can be very bright when your eyes are accustomed to the dark! When we tried to locate the source and got closer, it stopped. It was coming from a residential area. I had spots in my vision like someone took flash photos and I looked into the strobe.
One note; there was mention in the news of a quote from an FBI agent who said it had to be a sophisticated laser to track a plane for severla seconds at 8500 feet. I disagree. I believe with a braced or tripod mounted unit in combination with the beam divergence holding on target for a few seconds is easy.
Why does everybody think this is just a case of some kid who bought a handheld laser pointer and is trying to point it at an airplane that flew overhead?
Come on people, it doesn't take a whole lot of imagination to figure out that a combination of a commercial/scientific laser along with a good quality sighting scope mounted on a high quality tripod wouldn't be too difficult or expensive to slap together. Hell, just get a good laser and mount it on top of a good pair of military observation binoculars and you'd probably be ready to rock & roll.
It also doesn't take a whole lot of imagination to realize that from a mountain top or other high peak of land you could target aircraft flying directly towards your position from a few miles away. If it's flying in your direction then its horizontal and lateral positions won't change very much so you wouldn't need a sophisticated tracking system. You wouldn't even need a very high position if you intend on targeting aircraft that are landing - just an open area a mile or so from the end of the runway.
IAAP (I am a physicist). I do not work with lasers, but have taken a graduate level course in non-linear optics that primarily focused on lasers.
It is quite possible to damage a pilot's eyes at a range of a few miles, using only commercial laser systems. If done by competent individuals, it would probably involve a pulsed infrared laser (harder to detect, and the eye is more susceptible to near IR than to visible). A Nd:YAG laser (1064 nm) would be ideal.
Since a pulsed laser is used, there's no need for tracking the plane. A single 10-nanosecond pulse would be sufficient. At 10 - 20 pulses per second, you could just scan the sky in the area of the plane.
After reading the story, I did some rough calculations. For the above-mentioned laser, the laser beam would do damage (although likely not sufficient to totally blind the pilot) at ranges of up to two miles, and the beam would have a spot size several meters in diameter at that range. Obviously, with additional optics, range and spot size could be changed.
It seems to me that the laser could simply be mounted to a scope on a tripod (after some careful alignment), and that targetting by hand would work at least some of the time.
All this aside, I don't think the recent cases are anything to be worried about. More likely it's just a nutbar with a relatively weak visible laser (I assume the laser was in the visible range because the pilots reported it, and I doubt commercial planes are equipped to detect IR lasers). If it was someone serious, they'd be using IR lasers, and we wouldn't know until pilots started getting eye damage.
That said, the overall risk of plane crashes from this form of attack is low. If the airport and immediate area are kept secure (and they should be if only to guard against Stinger-style missile attacks), it's very unlikely someone with a commercial laser could get close enough to completely blind a pilot. Military or custom-built research lasers could blind from greater distances, but such systems are very finicky, and I can't see terrorists pulling that off.
Finally, I'd like to address a few points other people have brought up. If the polarization and angle of the beam are chosen correctly, virtually none will be reflected off the plane's window, and all will be transmitted (see Brewster's Angle). For modest laser powers, the damage to the retina will be localized to where the laser beam is imaged, leaving much of the pilot's vision intact. Bad for the pilot, but he could probably still land. For more intense beams, other damage mechanisms come into play (apparently for severe cases there is an actual popping sound perceived by the victim as the laser pulse creates a small shock wave inside the eye), and more of the victim's vision could be damaged.
Protective goggles aren't really an option, as they only protect against one wavelength. Attackers could then switch to a different type of laser (Ti:saph?). Combining goggles leads to virtually no light getting through.
References
Journal of Biomedical Optics 4(3), 337-344 (July 1999).
Big Sky Laser CFR-800 spec sheet