I think this is pretty petty, somebody needs to get a real life, eh? I've heard these lazer beams can do damage to the retina, anyone have any facts on this? Here's what they've discovered in NJ, as well as other airports:
I've been to events, e.g. Fireworks displays, festivals, etc. where the security has been beefed up. No alcohol, coolers, backpacks, etc. They had checkpoints with caution tape all over the river.I have seen kids playing with these flashing them at peoples' eyes, and security had to take the lazer beam objects away. Do you think they are dangerous, or just an annoyance?
And what about a terrorist threat? Do you really think they are that harmful to the pilots? And if so, how come the airports can't resolve this by tightening up security threats. ******************************************************** 01-02-05, 10:12 AM Fritzzs Well, all I can say is that you better hope your butt is not on the plane that the pilots get blinded by a beam....
A laser beam can be EXTREMLY dangerous, and you will not find someone sitting the runway with a laser gun aimed at planes... they will be miles away waiting for a nlane on approach for landing.. This is beyond airport security...
01-02-05, 12:47 PM methos Even the laser in a CD player can damage the retina. Our eyes are particularly sensitive to green, making the green lasers being used more harmful. Contrary to something I just read in a news article while looking into this, green lasers actually cannot travel as far as red lasers (shorter wavelengths, closer to the blue end of the rainbow, scatter more than longer wavelengths, closer to the red end). How far they can travel while still being resonably intense will vary largely depending on the laser.
There have been a number of incidents this year.
A pilot from Delta Air Lines had damage to his eye from a laser in September.
So far, there hasn't been any evidence linking any of these events to terrorists. One was a prank (apparently, the man didn't realize the potential harm), another was a man playing with his daughter and he didn't realize he had hit a plane (or, later, a helicopter investigating the incident). There are several other incidents where the culprit hasn't been found.
Thankfully, the chances that damaging a pilots eye (if you could manage to hit it precisely)would actually bring down a plane are slim because of the degree of automation in modern planes.
01-02-05, 04:29 PM Professor Part of the danger from lasers is that the beams are highly collimated, i.e., they don't spread out like the beam from an ordinary flashlight or spotlight.
So the full power of the beam is concentrated in a small spot even if it emanates from several miles away, just as if it came from right outside the plane -- there's no 1/R2 attenuation.
The pilot's retina may be damaged permanently by brief illumination. It's hard to imagine a good defense, other than the crew continuously wearing goggles.
Maybe some kind of high-tech windshield that could turn opaque within milliseconds after sensing light intensity above a certain threshold?
01-03-05, 11:40 AM methos The problem with the goggles would be that they would only block a specific wavelength, and so would be easily gotten around by switching to a red or other colored laser. Making the windows quickly turn opaque would save the pilot's sight, whcih is of course a good thing, but the true concern is the pilot being able to see the landing strip. Opaque windows would make that even worse than a laser as they would, I assume, activate whenever any part of the windows was hit rather than only in the case where the pilot was hit directly in the eye.
01-03-05, 12:06 PM frankvan I would be less inclined to worry about attempts to damage the pilot's retina than the possibility that it might indicate an attempt to use the laser as a means of aiming or guiding a projectile of some sort. Or perhaps practice or experiments along those lines. After all there is more than one set of eyes in the cockpit.
01-03-05, 01:21 PM teeceeum Exactly what I've been thinking, Frank.
01-03-05, 01:29 PM Professor Good point about the goggles filtering a very specific wavelength. And with tunable dye lasers, the bad guys could choose just about any color they wanted.
In my fantasy scenario for the windshield, only the portion transmitting the laser light would react by turning opaque. Yeah, sure... Wink
01-03-05, 08:12 PM AMoore
quote:Originally posted by soaringhorse: I think this is pretty petty, somebody needs to get a real life, eh? I've heard these lazer beams can do damage to the retina, anyone have any facts on this? Here's what they've discovered in NJ, as well as other airports:
Kids (some not so young as all that) playing with laser pointers has been a problem for some years. Seldom is anyone actually injured - the lasers available to the kids lack the power to cause injury themselves, but occasionally a driver is distracted enough to swerve, risking a collision.
As far as I could tell from that story and others that have appeared, this is a very low risk event being described -- it rather sounds as though someone in the Department of Homeland Security wants to be perceived as doing something about a terrorist threat, without having to actually do anything that might cost money or require real effort. In my opinion, they would do better to return our protective mechanisms to the state they were in prior to 9-11. We now have fewer air marshalls on airliners and are inspecting only about half as many cargo containers as we were.
Alan Moore
01-03-05, 09:23 PM teeceeum A flight bound from here to Chicago was "targeted" last night at 3,000 feet. How do the "kids" get up there?
01-03-05, 09:32 PM AMoore
quote:Originally posted by teeceeum: A flight bound from here to Chicago was "targeted" last night at 3,000 feet. How do the "kids" get up there?
With a perfectly ordinary laser pointer.
If you can see it, you can hit it with a laser, and 3000 feet is no distance at all, even for the weakly collimated beam of a typical "drug-store" laser pointer.
Alan Moore
01-03-05, 11:10 PM Professor I've poked around the Internet a bit for better information. Look at these articles from Scientific American, Straight Dope, and Dr. Greene (moderated by pediatricians) concerning "pocket lasers."
The consensus seems to be that serious retinal damage is unlikely from typical red-beam laser pointers in the range of 1-5 milliwatts, but that there is genuine concern about some of the newer green laser devices, which can deliver higher power beams at wavelengths to which the retinas are more vulnerable.
That said, everyone agrees that the victims can be temporarily "dazzled." That can't be good when you're trying to land an aircraft.
I guess I'll add this to the growing list of reasons not to get out of bed in the morning.
01-04-05, 08:59 AM teeceeum Can someone explain to me the geometry that allows someone on the ground to shine a light into the cockpit of a plane at 3,000 feet?
01-04-05, 10:02 AM soaringhorse
quote: Can someone explain to me the geometry that allows someone on the ground to shine a light into the cockpit of a plane at 3,000 feet?
Similar incidents have been reported recently in Utah and Ohio. On Monday, a pilot on approach to Cleveland Hopkins International Airport reported that a laser filled the cockpit at more than 8,500 feet. Air traffic controllers used radar to trace the beam to a suburban neighborhood in Warrensville Heights.
I can't imagine unless there is someone on a skyscraper rooftop or something, still smells fishy, huh?
01-04-05, 04:25 PM Ewood27 An ageing, and very senior, pilot was once asked whether failing eyesight was making it difficult to land the aircraft. He replied that he never looked out, but watched his copilot. "When he stiffens, I pull back!"
More seriously, how high is the Cleveland airport above sea level? The pilot's report of 8500' was probably above sea level, not above the airport.
01-04-05, 06:19 PM teeceeum Maybe I should have asked my question in the math forum.
01-04-05, 09:42 PM methos The geometry isn't too tough. If the pilot can see the ground, a laser from the ground can hit his eye. The cockpit intentionally gives the pilot a good view. Aiming it would be tougher (though not necessary if it was accidental).
Although it has really just hit the news recently because several happened right after each other, a study by the FAA last June said that "several hundred" incidents have been recorded over the past couple of years.
What I'm curious about is how radar could track light as one article claims. Of course, this is the same article giving $50 as the starting price for laser pointers (mine was $5).
01-05-05, 09:38 PM AMoore
quote:Originally posted by methos: - snip -
What I'm curious about is how radar could track light as one article claims. Of course, this is the same article giving $50 as the starting price for laser pointers (mine was $5).
It sounds as if the explanation had been edited into incoherance, as sometimes happens. The FAA monitors (via radar) the airplane's position and course and, near busy airports, other information reported by instruments on board the airplane, like altitude and heading. By combining this information with the pilot's report of the direction from which the laser beam came, they can get pretty close to the point of origin.
Alan Moore
01-05-05, 10:11 PM Professor
quoteAMoore: ) It sounds as if the explanation had been edited into incoherance...
Nice turn of phrase SmileI was thinking much the same thing about locating the source, since the pilot would presumably report something like, "from 11 o'clock with range 5-8 miles" at a time when his GPS coordinates are known. One recent news report narrowed it down to a particular suburb or section of town. Whether or not that's useful to law enforcement I couldn't guess.
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