Posted on 09/28/2013 7:45:21 PM PDT by MeshugeMikey
It was a Russian “trawler” so I think it can be safely assumed it was more powerful than the usual store bought lasers...:^)
Terrorists or not... easy to fix with a well placed sniper.
Muslims.
A hacked drone is a missile. Keep away from airports!
AH. Yes there might be some wrinkles in my “plan”
I’m not sure of the resolution of that incident but I believe I remember a pilot somewhere in the US undergoing that sort of harrowing mess some years back.
“Better to teach ethics and responsibility in schools.” and deport all the would be laser using jihadists....
thats what I was secretly thinking....
no one in their right mind would allow this to comtinue regardless of what steps had to be taken to see to it that it STOP.
Its not that the targets would be hard to see....
Im surprised that some mooselim jackass hasnt posted a video of their laser adventurism on facebook as yet.
In case you didn’t know a laser is considered a point source when ray tracing and figuring out where it goes. It does indeed drop off with distance squared. Moreover the DISTRIBUTION is NOT Lambertian.
The largest factors with lasers particularly visible wavelengths, include the atmospheric interference ( just traveling in air cause power drop and spot spread) and then distance travelled.
By the way your last sentence should give you all you need to calculate the actual power distribution of the laser at 2kilometers. You will find that spreading a half a watt into 2.5 meters makes it non damaging in any sense of the word.
The DANGER comes from staring directly at a beam. But one would not KNOW if they had encountered a direct shot until damage was done. For a visible wavelength lasr if you can see the beam it is not a direct hit on your fovea
But many of them are Muzzies.
http://www.debbieschlussel.com/1439/religion-of-laser-pointers-blinding-pilots/
Calculate the dropoff of a .1 milliradian beam spread, it’s not 1/r2 like a candle or led. Double the distance, w/cm2 does not go down by 4. When you get out to where diffraction enhances beam spread then it drops faster.
You are correct, the laser is not Lambertian unless it strikes a Lambertian surface. Beam shape is most likely Gaussian at farfield.
When I measure a laser beam up close then at, say, 50 feet, as long as the beam fits in the detector aperture, the energy is almost the same. If it’s in an atmospheric absorption band it will attenuate more.
Correct, it is “eye safe” at that range. But it can startle you and cause temporary blindness (flash blindness) when all you can see is afterimages. It will light up the aircraft cabin with a bright light if you are dark adapted, wrecking your night vision. Not a great thing when landing.
You’d need something beyond a handheld to do more than startle and distract a pilot.
Claims of “retinal damage” in cases where someone paints an airplane with a beam may be attempts to influence a potential jury. (I’m not sure about the Russian trawler vs pilot story, there is not enough information given in the clear for that one.) I’ve looked at a number of cases and the laser power was too low. One case was where a guy brought a work laser home for Halloween and zapped a copter (accidentally) at a range of 3 km- he used a 12 W Argon multimode! No retinal damage, there was no direct viewing plus the beam at that range was big enough to make even a 12W beam “eyesafe” according to the standards. For sure everyone within a couple of miles saw that beam!
On the other hand there are increasing cases of retinal damage at laser shows at big dance events. Frequently the laser is used to scan the crowd, so there can be direct intrabeam viewing. There were several cases of camera damage from laser light shows. In Russia two years ago the show operator scanned the inside surface of a glossy white tent and hurt some people with the light scattered off the tent, with I think a 6W diode laser.
You and I are on the same page.
Sounds like you are spending your career doing the kind of work I did for my career.
I think the thing that bothers me most about the ‘handheld laser’ is that people are truly unaware of safety and proper use. If they only blind them selves no problem. Blinding (or damaging) another is a big deal.
Mount a minigun on the aircraft that fires back down the path of the laser.
That should knock the problem back fairly quick.
I was just discussing this with a pal yesterday.
One wonders whether the ISRAELIS might not already have equipped thieir planes in such a manner?
Odd that this majority of these laser Attacks are occurring in Sharia Crippled “Great Britain”
Yeah, people don’t realize what a little Class 3B laser can do. And a handheld Class 4! I saw a 2.5W 477 nm (pretty blue) laser for sale. They’d ship it to your door and practically encourage you to “pop balloons, light matches, firecracker fuses, and melt plastic”!
Painting an aircraft cockpit would give the pilots a nasty surprise and deep afterimages, but in a living room you could certainly fry a line on your retina, or possibly your neighbor’s.
The Russian incident involved scattered light off a tent surface (the very definition of Class 4..lights fires and scattered light is dangerous.
I keep my lasers well contained and can only be used by well trained folks.....kind of like my fire arms
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