Slashdot Mirror
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.
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
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?
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
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!
http://www.judicialwatch.org/archive/newsletter/20 04/0104d.shtml
he Pentagon inspector general has asked the Navy to consider awarding JW client Lt. Cmdr. Jack Daly (Ret.) a purple heart for injuries he suffered as a result of being shot with a laser by a Russian spy ship. Curiously, however, the Navy to this day maintains Jack's injuries never occurred. And evidence compiled by Judicial Watch suggests the Clinton Administration covered up the attack in order to avoid international conflict.
"Jack Daly certainly deserves a medal for his injury from a hostile force," said JW President Tom Fitton. "For more than six years, the U.S. government has refused to acknowledge an attack of a U.S. serviceman in American waters."
"Lt. Cmdr. Jack Daly (Ret.) was partially blinded by a laser attack. The laser was fired at Daly from the Russian spy ship Kapitan Man in April, 1997, while Daly was on an official reconnaissance mission, flying over the Straits of Juan de Fuca, Puget Sound, WA. During his surveillance, which took place aboard a Canadian military helicopter, Daly felt a flash of brilliant light strike his eyes, causing him to turn away. Later in the day he would experience stinging in his eyes and sharp pains in his head. The next morning he awoke with a small pool of blood in one of his eyes.
Military doctors told Daly that he and his Canadian chopper pilot, Captain Pat Barnes (Ret.), had been shot at with a laser by the Russians. The damage would be permanent.
Rather than standing by their injured military official, however, Clinton Administration officials treated the incident as an inconvenient stumbling block on the path to improved relations with the Russian government and covered it up.
The Kapitan Man was not searched until several days later and only after at least 10 hours advanced warning given to the Russians. Though a thorough search should have taken 2-3 days, U.S. inspectors were aboard for less than 4 hours. Predictably, no evidence was found.
Judicial Watch currently has an appeal pending for Jack Daly against the Far East Shipping Company, the owners of the Kapitan Man."
no it is not.
any laser that the general public can get their hands on will DO NO DAMAGE to a pilot or even distract them.
first off even the high power green ones, at the 100 meters or MORE distance these people are at, they need to retrofit the laser with a tripod, fluid head and a high power scope just to hit the plane.
Now let's addin the fac tt hat the angle if incidence of the beam to the cockpit window is at such an extreme angle that less than 20% of the beam will pass through the window, and THAT will get attenuated further by the cockpit glass.
let's further add that the pilot is looking at the centerline of the runway and not directly at things that might be interesting, and if it's a clear sunny day a reflection glint off cars in the parking lot is 200 times brighter than any consumer laser.
this is nothing but a bunch of people freaking out about isolated incidents.
if I was able to get my hands on a targeting laser, Yes, that MIGHT be able to hit the cockpit window because of the gyro stablization of the optics and laser, but then it's infrared so NOBODY would know it was hitting it!
can I get my hands on industrial lasers? yeah if I look hard enough, but you certianly will not run them off some portable battery for longer than a few seconds.
it is NOT a serious problem. Quit being a scared soccer mom.
Do not look at laser with remaining good eye.
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