Laser pointers blinding pilots? Sounds implausible

[salimfadhley]

According to this article the "new" hand-held green laser pointers have been used by naughty kids/terrorists to blind pilots:

http://www.theinsider.org/news/article.asp?id=872

"You're in an airplane, you're on final approach and suddenly you can't see," said Dan Kidder, a spokesman for the National Air Transportation Association, a trade group. "You can't see your instruments. You can't see your runway. There's the potential for a major accident."

Does that seem plausible? I remember using hand-held lasers as a child in Physics lessons. We were always told not to stare directly into the beam, but they were not hugely bright and the optics were of poor quality meaning that by ten m from the soruce the beam had noticeably diverged.

Supposing somebody were to aim an excellent quality handheld laser at the cockpit of a flying aircraft: I'm guessing any "hit" on a pilot's eye cannot be more than instantanous. What's the possibility that it could blind? It seems rather remote to me.

Furthermore, the pilot would see the laser as a single point of light: Like a green dot on the horizon. At worst surely this could cause very localized retinal overload (like staring into a table-lamp for a second) but not the kind of blindness where you cannot see a thing.

And if this were true:
http://news.scotsman.com/uk.cfm?id=1416162004

Why bother with all that dangerous mucking about with easily discovered explosives when all you need t do is shine a light at an aircraft and watch it tumble helplessly from the sky? If that were true then the military would never bother with conventional anti-aircraft weapons.

[ZERO]

Even worse.... http://sportal.com.au/football-news-...er-probe-83755

[polomint38]

This could cause serious damage to ZERO, being just an eye.

[salimfadhley]

Even worse.... http://sportal.com.au/football-news-...er-probe-83755

This does sound somewhat plausible: I can imagine that if you are less than 100m from the source of laser light then it could be really distracting. That could be a serious problem if your business is accurately kicking balls. I reckon it would be really easy to spot exactly who was shining the light - you'd see a red dot even if it wasn't pointed exactly at your eyes.

On the other hand, unless the light was very bright indeed I doubt it would be visible beneath the stadium lights and flashbulbs going on.

A pilot friend @sounddoc twittered (just now) that the whole laser-pointer blinding pilots story is BS: A pointer would be ineffectual during the day and at night landing lights (which are designed to be visible in heavy fog) are considerably brighter than any hand-held laser-pointer.

[Tony Williams]

A few months back, during a news report about someone jailed for this offence, they showed a view from the air while someone on the ground was shining one of these lasers up at the plane. It was very dazzling, and would certainly have been a major distraction at a crucial moment when in the final stages of landing.

[skbuncks]

Perhaps not so BS afterall.

http://www.usatoday.com/news/washing...aircraft_x.htm

skb

ETA:

A wide range of people are believed to have been behind the incidents, Mineta said.
"Stupidity is not something monopolized by any age, or sex," he said.

lol

ETA2: http://news.smh.com.au/national/lase...0406-240f.html
and the ban in Australia, brought about in pat due to the targeting of aircraft http://www.customs.gov.au/site/content10444.asp

[Legaleagle]

http://www.hf.faa.gov/docs/508/docs/cami/0107.pdf


I think the use of the word "blinding" in media reports is inappropriate. What we are talking about is temporary impairment of vision and distraction, which could lead to a pilot making an error.

[Cuddles]

Does that seem plausible? I remember using hand-held lasers as a child in Physics lessons. We were always told not to stare directly into the beam, but they were not hugely bright and the optics were of poor quality meaning that by ten m from the soruce the beam had noticeably diverged.

As is usually noted in the news articles about this, the lasers in question are generally far more powerful than ordinary classroom pointers. One of the more common legitimate uses is for aiming telescopes, where having a beam able to reach hundreds of metres into the air can be very useful. Given that the problems are only caused for low flying aircraft, usually taking off or landing, that's enough range to be a real problem.

Supposing somebody were to aim an excellent quality handheld laser at the cockpit of a flying aircraft: I'm guessing any "hit" on a pilot's eye cannot be more than instantanous. What's the possibility that it could blind? It seems rather remote to me.

As Legaleagle points out, they don't mean that it causes permanent blindness, merely that it can dazzle them for anywhere from a few seconds to several minutes. When flying an aircraft, especially during the fiddly bits near the ground, that can be plenty to cause trouble.

Furthermore, the pilot would see the laser as a single point of light: Like a green dot on the horizon.

How narrow do you think the beams are? Even very close it's easily the size of your pupil. Of course, your claim here is hardly consistent with your earlier claim that these pointers have low power beam that have diverged a lot within 10s of metres.

At worst surely this could cause very localized retinal overload (like staring into a table-lamp for a second) but not the kind of blindness where you cannot see a thing.

You don't need to be completely blind in order to be unable to read your instruments.

Why bother with all that dangerous mucking about with easily discovered explosives when all you need t do is shine a light at an aircraft and watch it tumble helplessly from the sky? If that were true then the military would never bother with conventional anti-aircraft weapons.

Obviously planes don't magically drop out of the sky the instant the pilot has a little trouble with his vision, and I've never seen anyone suggest that to be the case. That doesn't mean that there can't ever be any danger from doing this.

Quite frankly, it doesn't seem as though you're particularly interested in honest debate here. You're indulging in the most ridiculous hyperbole apparently without having done the most basic research. Yes, some laser pointers are easily powerful enough to cause problems with vision. Yes, having problems with vision is not a good thing when flying a plane. No, laser pointers aren't some magic weapon able to instantly destroy any aircraft they're pointed at. Seriously, what argument are you trying to make here?

[salimfadhley]

As is usually noted in the news articles about this, the lasers in question are generally far more powerful than ordinary classroom pointers. One of the more common legitimate uses is for aiming telescopes, where having a beam able to reach hundreds of metres into the air can be very useful. Given that the problems are only caused for low flying aircraft, usually taking off or landing, that's enough range to be a real problem.

I'm not denying that it's theoretically possible to aim a sufficiently powerful laser at a pilot's eye and cause temporary dazzling. I am sceptical that it has every actually happened as a consequence of a cheap hand-held laser pointer, the kind they said could be bought for around $5.

Note the heading of the thread. I will say it again, that I fully understand that lasers are potentially dangerous things. I even know that defence companies have been attempting to build blinding weapons from lasers, however the title of the article I was responding to was "Cheap laser pointers from eBay used to blind aircraft pilots".

As Legaleagle points out, they don't mean that it causes permanent blindness, merely that it can dazzle them for anywhere from a few seconds to several minutes. When flying an aircraft, especially during the fiddly bits near the ground, that can be plenty to cause trouble.

This is my other problem:

We all know that a prolonged direct hit to the eye can cause dazzling or even permanent damage. The amount of time required to dazzle or damage depends on the power of the beam and the degree to which the beam has attenuated or diverged. We also have the problem of aiming the beam: Supposing I were to try and aim at the eye of a pilot 50m away (which we all agree is fairly close range) - the subtle motion of my hand will mean the dot will be dancing about wildly around the target. Even variations in air pressure can cause a measurable deflection over 50m. Unless the laser was very powerful, the chance of this connecting with the pupil for long enough to cause even dazzling still seems unlikely at handheld powers.

And let's not forget: We are trying to target a moving object. The only position from where this would be an 'easy' hit would be if you were directly in it's flight path: For example, if you were standing just beyond the runway and shining a laser as the plane was coming in to land.

Note once again that I'm not denying that it would be distracting or worrying. A pilot might assume that he was being targeted by some kind of weapon system. Somebody once shone a laser pointer at me while i was cycling around London. It was disconcerting.

How narrow do you think the beams are? Even very close it's easily the size of your pupil. Of course, your claim here is hardly consistent with your earlier claim that these pointers have low power beam that have diverged a lot within 10s of metres.

At school (more than 20 years ago) the physics department had acquired a number of red lasers. At source the beam diameter seemed to be less than 1mm, however by 15 metres the lasers projected a thin line of length .75cm to 4cm on the wall. I guess it was due to optical flaws in the source's lens. I've noticed that most cheap semiconductor lenses have some degree of divergence due to optical flaws at the interface between the laser and the air.

Obviously planes don't magically drop out of the sky the instant the pilot has a little trouble with his vision, and I've never seen anyone suggest that to be the case. That doesn't mean that there can't ever be any danger from doing this.

See my comment below:

Quite frankly, it doesn't seem as though you're particularly interested in honest debate here. You're indulging in the most ridiculous hyperbole apparently without having done the most basic research. Yes, some laser pointers are easily powerful enough to cause problems with vision. Yes, having problems with vision is not a good thing when flying a plane. No, laser pointers aren't some magic weapon able to instantly destroy any aircraft they're pointed at. Seriously, what argument are you trying to make here?

Any hyperbole was intended to summarize the articles I linked to - they presented cheap consumer lasers as an immediate, significant risk to air-travel.

I fully accept that the beam from high-power lasers are visible from aircraft (there's youtube videos to prove it). Furthermore I accept that :
* a direct, prolonged hit,
* from a sufficiently powerful laser,
* at sufficiently close range,
* or with an accurate aiming system

... could could cause dazzling or possibly permanent eye-damage to an occupant of any vehicle with a window.

I do not think the above is ever likely to be the case when the laser-operator is outside an airport perimeter and using a cheap hand-held battery-operated laser pointer and the target is a plane in motion.

[salimfadhley]

Another thought just occurred to me:

What's so special about lasers? Any sufficiently bright light can be distracting. If you take a not so bright light and flash it quickly enough it can be annoying or even trigger seizures. There are hand-held LED flash-lights which can produce brighter beams which are visible from great distances. Drivers are often distracted by roadside adverts or particularly attractive members of the opposite sex. Even forgetting to dip your beam for oncoming traffic is enough to cause temporary dazzling.

When you start listing 'em there are plenty of common things which are known to distract vehicle operators.

Compared to the above, I feel that the evidence to support the laser stories seems very weak. :-)

[Tony Williams]

I fully accept that the beam from high-power lasers are visible from aircraft (there's youtube videos to prove it). Furthermore I accept that :
* a direct, prolonged hit,
* from a sufficiently powerful laser,
* at sufficiently close range,
* or with an accurate aiming system

... could could cause dazzling or possibly permanent eye-damage to an occupant of any vehicle with a window.

I do not think the above is ever likely to be the case when the laser-operator is outside an airport perimeter and using a cheap hand-held battery-operated laser pointer and the target is a plane in motion.

It's more serious than that. First of all, a "sufficiently powerful laser" at "sufficiently close range" can cause permanent blindness instantly, and I recall reading that it has done so in laboratory accidents. Laser weapons have been developed to do just that, see page three of this: http://www.allbusiness.com/specialty.../492548-1.html

"Laser weapons, which are likely to be relatively inexpensive and light-weight, can be mounted on assault rifles and used to scan the field in front of the attacker. At a distance of one kilometer, which is within the weapon's range, the invisible beam will spread to a width of at least 50 centimeters. Anyone within that range who glances at the beam, be it a soldier, a journalist a nurse or a civilian, will be blinded instantly."

This does, of course, describe rather more than a cheap commercially-available one. However, as I have already posted, there was a practical demonstration in a news clip of the effect of one of these cheap, hand-held lasers aimed from the ground at an aircraft passing overhead. The beam merely flashed across the camera lens for a moment, but all that could be seen at that instant was a brilliant flare of green light. I can well believe that a pilot hit in the eyes by such a beam, even for an instant, would have his vision impaired for a few seconds.

I'm not sure what point you're trying to make with the "any vehicle with a window" comment. Dazzling the pilot of an aircraft which may have hundreds of passengers on board, just as it's coming into land, is a damn sight more serious than dazzling a car driver, who can slam the brakes on and stop...

IMO it is rightly considered a serious act, punished severely.

[Pebble]

IMO it is rightly considered a serious act, punished severely.

But the US military has now admitted shining lasers at aircraft as part of a secret programme:

A day after the Department of Transportation urged pilots to report hazardous laser beams aimed at aircraft, the U.S. military said it is testing a system to beam red and green lasers at aircraft in the Washington area as a warning when they enter restricted airspace.
Source: Washington Post, "Military Tests Lasers To Warn Off Aircraft", 14 Jnauary 2005.
http://www.washingtonpost.com/wp-dyn...2005Jan13.html


I wonder about this. Lasers come in many forms, very high energy lasers can burn anything, military style lasers can track moving objects such as cockpits, and your article suggests that widefield lasers are being developed by the military. With these high end versions it is easy to see the potential use to terrorists, but harldy useful to pranksters.

Now jumping down the throat of some teenagers looking for kicks based on what the military have produced and might become available to terrorists, looks like an example of bullying those you can because of generic unfocused fear.

If you want to convince me that there has bee a serious transgression, I would want some evidence that standard handheld lazers (or what ever the kids were using) has been shown to be capable of disabling/severely distracting, when pointed at an object several hundred meters away moving at 80+ miles per hour. Further I think we need to factor in the fact that there is a co-pilot, and multipile automatic controls to prevent crashing.

[chaggle]

Shining bright distracting lights at landing aircraft? It doesn't matter if the risk is minimal or even non-existent. The perps either think they are causing problems or they know that they are not. We should just book 'em for being f***ing stupid.

[Tony Williams]

If you want to convince me that there has bee a serious transgression, I would want some evidence that standard handheld lazers (or what ever the kids were using) has been shown to be capable of disabling/severely distracting, when pointed at an object several hundred meters away moving at 80+ miles per hour.

"However, as I have already posted, there was a practical demonstration in a news clip of the effect of one of these cheap, hand-held lasers aimed from the ground at an aircraft passing overhead. The beam merely flashed across the camera lens for a moment, but all that could be seen at that instant was a brilliant flare of green light. I can well believe that a pilot hit in the eyes by such a beam, even for an instant, would have his vision impaired for a few seconds."

Is that not enough for you? Or do you want to see a plane crash before you'll be convinced that there's a genuine risk

Further I think we need to factor in the fact that there is a co-pilot, and multipile automatic controls to prevent crashing.

You have got to be kidding. Planes do not land automatically but under manual control. And we are talking about the last few seconds of flight before landing. And suppose the pilot says to the co-pilot "what's that flickering light?" so they're both looking just when the full beam sweeps over them.

I can just hear the defence in court: "My client believed that it was perfectly OK to dazzle the pilot - the crash was the co-pilot's fault for looking in the same direction."

[Harryprice]

I believe when pilots are flying (and landing) at night they have the cabin lights off to preserve night vision. A quick bright flash from a laser might destroy the night vision of both pilot and co-pilot. It can take 30 minutes to fully restore. Bit too late if you're landing at the time ...