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Laser Injures Delta Pilot's Eye
stormfish writes "The Washington Times is reporting that laser light from an unknown source injured a pilot's eye as he was flying a Boeing 737 from Dallas to Salt Lake City. A 5 milliwatt laser pointer is strong enough to damage a person's eye, and stronger laser's are not that hard to come by. Unfortunately, having pilots wear colored laser safety glasses would be impractical as that would make it impossible to interpret the colored symbols on paper maps and cockpit displays."
Class IIIa (>5mW) 532nm green laser pointer (ThinkGeek)
Class IIIb (>15mW) 532nm green laser pointer (MegaLaser)
Class IIIb 200mW handheld green laser (Information Unlimited)
It's even possible to get small, portable Class IV (potential instant severe eye damage, even from diffuse or reflected beams; this is the class of laser which also includes burning and cutting beams) lasers:
Various Class IV portable lasers, including a small battery powered 2W diode laser (Information Unlimited)
The front windows of a commercial aircraft and objects in the cockpit could easily reflect and refract a beam from the ground in ways that would be at a minimum very distracting and unsafe, and potentially damaging to eyesight.
Information about laser classes.
I would propose that actually physically seeing out of the window is less and less neccessary. At the same time oLED and plasma displays keep getting better. Why not recreate environment using cameras and flat displays? Sure it wouldn't look normal at first, but keep in mind, pilots all get certified on simulators.
Plus, it opens the door to all sorts of useful heads up display possibilities (porn).
They said that they saw a laser beam in the cockpit. A short time after that the pilot felt a burning sensation in his eye. Did you bother to read the article?
:wq
It would not be impractical for the pilot to wear safty glasses during the takoff and landing phases of flight, and have the copilot dictate to the pilot important information and peform tasks (ie. airspeed, gear down, flaps out). This is how it is done to a certain extent already. And after takeoff, the pilot could remove his safty glasses. In fact, this is how the C-130 crews do it when landing in the arctic. The snow is so bright that the pilot must look outside the whole time while the copilot reads things off the instruments.
A multi-watt laser with a decently large aperture and a TEM 00 spatial mode would be a different story.
I know some folks workin' on it.
Here was one demo.
Here's a picture.
... in several armoured vehicles that I have been in. There is a slight tint that reveals the laser protection coating over periscopes and aiming sights(no, this is not a secret) and has been in use for years.
Time for someone to reinvent the wheel?
If there's a radio failure, the control tower uses light signals -- under ordinary circumstances, you need to remember that airport lights (runway, taxiway, etc) are color coded. As a pilot, you *must* be able to tell the difference between red, green, yellow, blue and white lights.
(Yes, I am a pilot)
Ian Ameline
You are thinking about Jasper Maskelyne.
I have a book about him that I am sure has some made-up stuff in it, but a lot of factual events as well. Most of the tricks you read about in WWII was due to him.
The most amazing thing about this guy is he managed to walk into the war department and convince them to let him go to the front and construct illusions. Army folks are not prone to letting civillians wander in and start telling them what to do with their troops and supplies!
This has been debated for a while, but recent studies have borne out the idea that class IIIa lasers, up to 5mW, don't cause permanent injury to the retina.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd= Retrieve&db=pubmed&dopt=Abstract&list_uids=1111526 6
If it is a strong enough laser, you can just make it scan (a simple mirror attached to a small motor will do it). You'll create a light triangular plane, instead of a light line.
By staying at the side of the runway, and pointing your light 'wall' to the plane, you'll greatly enhance your chances that the pilot's window will cross the laser beam, and that the pilot's eye will be hit. A high-speed vibrating mirror with an adjustable vibration angle will further enhance your odds (you can have it crossing the window hit area more times per second).
Am I going to jail for telling this?
There is no way a laser from the ground could get in through the window, given the angles.
While I agree that a ground-based attack seems highly unlikely, and that the Washington Times is looking for any angle on terrorism, the angle from the ground to a cabin during decent is not that unlikely.
Salt Lake City is surrounded by the Washatch Mt Range. They are approximately 4K-5K feet above the basin floor surrounding the city and the approach to SLC takes flights to elevations where it would be possible to point a laser directly into the cabin.
Also, considering the velocity,..
There's the kicker. The terrorist, or dumbass prankster, would have to be extremely lucky to get a laser into a pilots eye, at extreme distance, and into a plane that is traveling in excess of 160 mph.
"Rocky Rococo, at your cervix!"
Everything I know about the subject I learned from this article, where the dude points out:Guess I should have linked that in the original post. I just didn't want to use my google.
There are no trails. There are no trees out here.
The article lacks enough information... Often times direct exposure from handheld pointers has been cited and hyped as if it was a 40 watt 523nm YAG laser.
There are rules and restrictions for directing coherent laser light up into the sky at night. You generally file a report with the center for disease and radiological health.
In addition to all of this, even with a 5 watt argon, at a great distance the beam will fall out of coherency. There is a big difference between a beam that is tightly focused / coherent, and one where the output is spread on a 12" circle (temOO?).
Another big factor is if the laser is moving real fast, once again the light is spread out...
The US has pretty strict laws on this stuff, where as other countries do not. You will see pictures of crowd scanning from high powered lasers in other countries, but you won't generally find crowd scanning above 5mw here.
There is more information about lasers at the laser faq site (google for Sam's Laser Faq). Laser-FX International also has a bit of information about laser show setups. I have some pictures of my 150mw argon-ion and large frame argon that puts out somewhere between 2.5 and 5 watts of power at my homepage ( http://users.757.org/~ethan )... Lots of pictures.
Without colimating optics, the laser beam from the 150mw argon spreads to 6" or more across at a distance of 1000'.
Southeastern Virginia REPRESENT!
Apparently YOU didn't bother to read the article.
I was on a Search and Rescue mission in CAP and we were targeted by a strong green laser. I was the mission observer and instructed the pilot to look away. Initially it passed by us fast but then it illuminated the cockpit. We got closer but it stopped.
If we had a better location on the source we would have been more active tracking it down. I would not want to be the person caught interfereing with an Air Force assigned SAR mission.
It's amazing that your one info about pilots eating different meals is accurate, and yet you still think that airplanes have navigators.
Some old airplanes still have Flight Engineers (boeing 747-1/200s used in cargo service, 727s), but those are getting few and far between. Flight Engineers have never been "flight capable", whatever the heck that means (and yes, I have flown large products made by boeing from the left seat).
I am not sure when the last time a commercial flight in the USA had a navigator was, but, well, it was a heck of a while ago.
I don't mean this unkindly...mostly. But if you really are a rated pilot, then you missed some very fundamental knowledge. Colors are extremely important. You may think you can reason it all out by context, but as you fly more you're going to realize that there are just too many different ways things are done in aviation. Color-blindness can kill. There's a reason you were tested for it when you took your flight physical.
You should also start working on, or reading up on your IFR rating, before posting about it. At some point, all but the most sophisticated aircraft need to transition between IFR and visual. (some commercial planes can literally land themselves) Sometimes it's only a hundred feet off the ground, but there is always a transition. And when you make that transition, things like the VASI/PAPI/etc (any multi-colored glideslope indicator) are extremely important to get right. Things like making sure you're not landing on a taxi-way are important to get right. (Even multi-thousand hour pilots have done that)
I'm guessing you're newly rated, in which case welcome to the club. But you're making some very dangerous assertions that I hope doesn't indicate a dangerous flying attitude.
After a couple of hours on ebay, I was pretty shaken. Laser heads in the multi-hundred WATT (not MW) range are readily available to the public, no liscense no oversight. I asked a friend who does laser research about this, and he told me that while it was illegal to sell a high-powered laser to the public, the parts weren't restricted. So, a company can sell you a high power laser head, and next week the power supply, columnating lenses and whatever else you need, they just can't assemble it for you.
This is like saying that gun shops can sell all the parts for RPG's, but they can't actually load it for you!
Generally, I'm in favor of minimal govt. oversight, and I don't care for most gun-control laws etc. But NOBODY needs a 1500 watt UV laser for 'personal use' any more than I need tanks and howitzers for deer hunting! The add linked in previous responses showing a 200W laser-pointer shaped like a gun are just frightening. That's not a laser-pointer, it's a weapon, and I certainly don't want it pointed at me by some pimply-faced wanna-be geek trying to impress his friends!
If a pilot can see the ground, presumably the ground can see the pilot.
What I'm getting at here is that it doesn't matter how the windows in the cockpit are angled. If the pilot has line-of-sight with a point on the ground, it follows that a person standing at that point on the ground has line-of-sight back to the pilot, and therefore could have shined this laser into his eye.
A competent reporter would have double-checked this story against the Airport/Facility Directory, which contains warnings of areas where laser light shows may be present. I don't have a copy of the relevant A/FD, but that's the *first* place I'd look for an explanation. It wouldn't surprise me in the least to find that the pilots simply didn't know of a temporary (or permanent) laser light show in the area.
p
In Korea, long hair is for old people!
Thas was "Jasper Maskelyne". From the Discovery channel program I saw, he took a military spotlight, added a couple of conical mirrors so that the light would be reflected outwards in a starburst pattern. These mirrors would then rotate, causing the starburst pattern to rotate with it. Depending upon the weather conditions, this pattern would be visible for a radius of two to three miles up through the atmosphere. To completely conceal a particular area, dozens of these spotlights would be placed all over the desert.
We can only imagine how disorientating it would be for the pilots at that time to look out and just see alternating dark and white bands travelling at different speeds on each side of the plane. It would be a fairly simple to simulate this using an animation package.
Vintage computer adverts: http://www.vintageadbrowser.com/computers-and-software-ads
If you can see any point on the ground, someone at any of those points on the ground could hit you with a laser.
There's a link-collection about anti-personell lasers (including blinding ones) with similar stories. Seems old, but relevant.
Sig. under reconstruction.
THis kind of thing was a problem for the US during the first Gulf War. Basically, a laser would be pread with a (parabolic?) mirror, an F117 would fly into the beam, the night-vision camera hooked into the pilot's helmet would be overloaded, and the pilot would be blinded for a second or two, enough to lose control and crash.
One countermeasure that was later looked into was to use a lens coating with a non-linear response - it remained clear for most light intensities, but went opaque almost instantaneously (in milliseconds) when the intensity went over a certain threshold.
The reason I know about this was that my nonlinear optics professor had an amusing story about being invited to give a lecture on his research in the US, only to find when he arrived that it was to a military lab with several times more people working on the field than the amount doing the same research, but publically.
No doubt some bright spark is thinking of trying to sell the same tech to commercial jet makers now, especially since the new invadee paradigm is to just let the Americans in, wait till they relax, then commence the guerilla warfare.
-- Proud descendant of semi-nomadic cattle-herders.
Though to add to that, the typical green laser looks 4 times brighter than the typical red laser. This is because your eyes are 4x more sensitive to the green wavelengths. The power may be the same (and the damage potential), but a persons perception of a green laser is almost always that is it "more powerful". Plus high power lasers usually ARE green. It's relatively easy to make a highpower argon laser, but high power red/orange (Gold vapor) lasers are much less common.
Contrary to popular belief, coding is not all free blow-jobs and beer. Those things cost MONEY!
I've occasionally wondered that myself, so I did a little googling and found this Austrian Airlines article which had a reasonable explanation:
A marriage is always made up of two people who are prepared to swear that only the other one snores.
You're thinking of the Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, including the Moon and Other Celestial Bodies (eek, what a wordy title).
:In carrying on activities in outer space and on celestial bodies, the astronauts of one State Party shall render all possible assistance to the astronauts of other States Parties. ... but that would only govern the activities of the Soviets in space.
Unfortunately, there's nothing directly on this topic. There's things like
Likewise:
States Parties to the Treaty undertake not to place in orbit around the earth any objects carrying nuclear weapons or any other kinds of weapons of mass destruction, install such weapons on celestial bodies, or station such weapons in outer space in any other manner.
The moon and other celestial bodies shall be used by all States Parties to the Treaty exclusively for peaceful purposes. The establishment of military bases, installations and fortifications, the testing of any type of weapons and the conduct of military manoeuvres on celestial bodies shall be forbidden. The use of military personnel for scientific research or for any other peaceful purposes shall not be prohibited. The use of any equipment or facility necessary for peaceful exploration of the moon and other celestial bodies shall also not be prohibited.
Putting nukes in space is off limits, as is military activity on the moon.
I agree on the assholes part. The Russians were strongly convinced the Shuttle was a military vehicle, though. (And in fact, some of the capabilities of the Shuttle were required by the Air Force so they could go steal Russian satellites if they felt like it). IMO, though, pointing a laser at the crew of any aircraft or spacecraft with sufficient power to temporarily blind them is equivalent to showering them with gunfire; that is, an overt act with a strong possibility of killing or injuring the crew that could be considered an act of war.
The threshold for damage to the eye from visible-wavelength laser exposure with a 0.1 second duration (about the time it takes you to blink) is a fluence of about 0.3 mJ/cm^2 (see D. Sliney and M. Wolbarsht, Safety with Lasers and Other Optical Sources, (Plenum, 1982), Fig. 8-2), which corresponds to an intensity of 3 mW/cm^2.
If you multiply 3 mW/cm^2 by 20 square feet you get about 90 watts. Not exactly a hand-held device!
Having worked with Class IIIb Lasers for 25+ years I can attest to the fact that it is nearly impossible to incur eye damage from 5-15 mW. You reflexively look away and blink. In order to incur damage from such a laser it would require:
1.Anesthetizing your eyelid muscles
2.Anesthetizing your eye muscles
3.Mounting your head in a clamp
4.Firing the laser point blank into your eye for 10 min.
This would cause temporary damage.
In addition, while the laser beam is nominally collimated over distances of tens of meters the beam spreads, reducing the energy entering the eye by an inverse square relation.
This is not to say that lasers are not hazardous, something in the 1 Watt range can be seriously dangerous to your retina. But the inverse square law still applies over long distances. Pointing and tracking with an accuracy of 1cm over several kilometers is spectacularly difficult as well.
Eye-popper lasers have been evaluated by both the US and the Russians but they have had little effectiveness. They have been banned from the military as inhumane. Usually banned weapons tend to be both inhumane and ineffective.
With a big enough laser (>>10W)you could injure a pilot, in the same fashion you can bring down a plane with a sniper rifle, it's possible, but highly unlikely, and not a particularly good terrorist tactic.
A kamikaze falcon or the sudden release of a crate full of pigeons would be more effective by orders of magnitude.