Take a look at this story. Can lasers be used to disrupt planes in flight?
Take a look at this story. Can lasers be used to disrupt planes in flight?
I don't know anything about the story, but the answer to your question is "yes". Big lasers can easily blind a pilot. NASA uses lasers to get the range of satellites, and has to be careful when pointing them.
In a related item, when I was in Australia visiting the Tidbinbilla radio telescope station, they told me they have to be careful when transmitting to distant spacecraft with the 70 meter dish-- the microwave energy from the dish can fry aircraft electronics!
ICRC: New Protocol on Blinding Laser WeaponsOriginally Posted by N C More
International Conference of the Red Cross narrative of the 1995 adoption of the Geneva Conventions Protocol IV banning the use blinding lasers as weapons.
The article also provides some examples of blinding laser development by China and the US.Protocol on Blinding Laser Weapons (Protocol IV)
Adopted 13 October 1995
It is prohibited to employ laser weapons specifically designed, as their sole combat function or as one of their combat functions, to cause permanent blindness to unenhanced vision, that is to the naked eye or to the eye with corrective eyesight devices. The High Contracting Parties shall not transfer such weapons to any State or non-State entity.
In the employment of laser systems, the High Contracting Parties shall take all feasible precautions to avoid the incidence of permanent blindness to unenhanced vision. Such precautions shall include training of their armed forces and other practical measures.
Blinding as an incidental or collateral effect of the legitimate military employment of laser systems, including laser systems used against optical equipment, is not covered by the prohibition of this Protocol.
For the purpose of this protocol "permanent blindness" means irreversible and uncorrectable loss of vision which is seriously disabling with no prospect of recovery. Serious disability is equivalent to visual acuity of less than 20/200 Snellen measured using both eyes.
Originally Posted by ICRC
Air forces have been aware of this threat for some time now.
Whoops! ops:The SkyPointer™ should not be used when others are imaging, as a sweep of the beam through the imaged field might register in the exposure.
Concerning lasers and aircraft, may I suggest the following two NTSB reports:
http://www.ntsb.gov/ntsb/brief.asp?e...7739&key=1said a laser beam swept past the cockpit and he immediately experienced eye pain and was completely blinded in the right eye. After image effects also induced a blind condition in his left eye. He said the total inability to see lasted 30 seconds, and for an additional 2 minutes, he could not focus on or interpret any instrument indications and was completely disoriented in his spatial relationship to the vertical.
There was a Readers Digest article several years back about a U.S. helicopter pilot that was blinded by high-powered laser light from a Russian spy ship. I think he suffered permanent damage, and lost his wings.
But the really bad part was, the U.S. government decided not to prosecute the ship's crew, or the Russian government. It was a political decision. Anyway, the pilot tried to get hushed up by his superiors, and when he didn't, he was either discharged or forced to retire I believe. But he still managed at least to tell his story to a highly disseminated magazine. I wonder what became of the fellow.
Quite frankly with all this commercial airline attention on lasers, I'm surprised this older case hasn't resurfaced.
This got a little more press around here, since one of the planes was near Cleveland.
I have to think someone was doing a good job of aiming if they could hit the cockpit window at 8500 feet. It had to be mounted and with some sort of "spotter scope" at the least. I also heard it was a green laser, less common than the universally available red laser pointers (help me out Laser Jock - Helium Neon?).On Monday, a laser beam was directed into the cockpit of a commercial jet flying about 15 miles from Cleveland Hopkins International Airport at an altitude of between 8,500 and 10,000 feet, FBI special agent Robert Hawk said. It was determined the laser came from a residential area in suburban Warrensville Heights.
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I saw this story on TV last night and it's certainly disturbing...the idea that this could be some type of terrorism keeps crossing my mind! No, I don't like this at all!Originally Posted by Swift
Originally Posted by SeverOh, dear.10 October 1984 Terra-3 illuminates US shuttle.
After the American decision was taken into 1983 to initiate the 'Star Wars' strategic defence initiative program, Minister of Defence Ustinov requested that the Americans be challenged. As a 'warning shot' the Terra-3 complex was used to track the space shuttle Challenger with a low power laser. This caused malfunctions to on-board equipment and temporary blinding of the crew, leading to a US diplomatic protest.
Green? He-Ne is still pretty far in the red (633 nm). There are green laser pointers, but I seriously doubt that they would be intense enough to cause pain and temporary blindness from that far away. I'm thinking a solid-state doubled Nd:Yag like this is more likely. They are small, powerful, relatively inexpensive, and commercial available.Originally Posted by Swift
If they verify that these are terrorist acts, I fear that they will start regulating these things. That will be a real nuisance for legitimate research labs (like mine).
Edit to add: If they verify that the wavelength is 532 nm, it almost immediately eliminates the possibility that these planes are being hit by accident. :-?
Just thinking about the cockpit arrangement. How could a ground based laser get a line of sige to the pilots eyes? Unless it was based on high ground a the plane was very low?
According to news reports, the Cleveland laser was apparently aimed from a neighborhood near the Randall Park Mall in Warrensville Heights. Here's a link to the topographic map at Terraserver
Elevation at Warrensville Heights is approximately 1000 feet above sea level, give or take.
In This view, I'd like to point out that aircraft approaching Cleveland Hopkins Airport from the east usually fly somewhat south of the lakeshore, but roughly following it. Sometimes more north, sometimes more south, sometimes turning out over the lake and back in directly over downtown Cleveland, and sometimes flying west of Cleveland and turning back to the airport, but rarely south of Warrensville Heights. I know this because I frequently travel to and from the east coast from Cleveland. You might imagine why this topic interests me...anyway, the usual flight approach takes us north of Warrensville but south of the lakeshore. Assuming the jet was at 8500 feet, 15 miles from the airport, its angle of descent would roughly be 1.5 degrees, if my math is correct. Pilots out there, please forgive any ignorance, this is a rough estimate only. The angle of the laser beam would be steeper, of course, since the jet wasn't 15 miles from Warrensville. Based on the topo map, I estimate that if the jet was 15 miles from Cleveland, it was about 10 miles from Warrensville. This results in an angle of about 9 degrees for the laser, which I believe is flat enough for a laser to hit the cockpit windows.
On a related note, is there any way to treat cockpit windows in order to filter or diminish laser beams?
They could paint them with a lead-based yellow-orange paint.Originally Posted by Paul Sandoval
Wouldn't hitting a cockpit window sized target at that range and speed require some sophisticated equipement? For some reason all these related events sound fishy to me.Based on the topo map, I estimate that if the jet was 15 miles from Cleveland, it was about 10 miles from Warrensville.
I just did some quick math. If your scope and laser were to be out of alignment by only .01 degrees you will have missed your target by 9.215 feet. That's bigger than a cockpit window. You would have to be within .001 degree tolerance to even hit a stationary window at this range. Sounds difficult to me, especially when you throw in the fact that the plane is moving at a high rate of speed. But then again, maybe I'm wrong.As I understand it from other discussions, extremely sophisticated equipment would not be required. Here's a link to a construction laser:
One of these, coupled with a spotting scope and mounted on a tripod, could do the deed, apparently.
There is, of course, the possibility that the perpetrators have been trying to hit a lot of planes with their lasers and have been very lucky in their most recent round of attempts. Assuming that the Cleveland laser-shooters tried to hit every jet that came along and were successful with the one jet, it lowers their rate of success quite a bit. I am not inclined to believe that they are able to target a plane at random and hit the cockpit every time. I dunno...
I've got two questions:
1. Can we rule out the possibility that it was just an amateur astronomer who decided to get the range of an airplane flying over and accidently pointed the laser at the cockpit windows?
2. Is it possible that the laser was used as a ranging device for a more conventional weapon, like a missile launcher? The fact that the laser hit the cockpit windows could just be a coincidence.
It has been asserted that in the Cleveland incident, the laser shone into the cockpit for "two to four seconds", an unlikely amount of time if someone had been using a laser to sight a telescope.
The idea that it might have been a target designator makes more sense to me than the blinding idea.
The latter seems most unlikely to cause the plane to crash. First of all, you'd have to blind both pilots so fully that neither could use either eye for a considerable amount of time. They would have to be so disabled that they could neither fly the plane themselves nor get it onto autopilot (after which, presumably, a number of options would become available, including staying aloft long enough for one of the pilots to recover some sight). It's hard to imagine any "critical moment" scenario in which a momentary disabling of one pilot would be enough to cause a catastrophic result.
But if you could illuminate a plane with a target designator (and you have a laser-homing weapon on hand), you've got a real chance to bring it down.
So it seems likely to me that this was either a "trial run" of a terrorist plot to shoot down a commercial jet with a laser guided missile, or possibly an accident or practical joke. I doubt it was an attack in itself.
Let's hope the guilty party is soon discovered.
But, a green laser instead of infrared? Do any military targeting systems use green? Why give away your intentions to human eyeballs?Originally Posted by Donnie B.
You can easily get a lot better than .01 degrees--just consider a target rifle. At two hundred yards, that's an inch and a quarter.Originally Posted by ff
If the plane was on low approach, at ten miles or so, it would almost look stationary, even if it were coming at high speed. It could even have been handheld, since the device is its own "pointer".
Well, it might look stationary, but someone said that the laser shined in the cockpit for two to four seconds. If the plane was traveling at only 200 mph it would move about 586 feet in two seconds time. I seriously don't believe that Average Joe can pull this off. Too much precision involved.Originally Posted by A Thousand Pardons
If it's the same pilot that they interviewed on NPR, then the article was completely wrong. He had some momentary vision problems, but that was it.Originally Posted by archman
Oh, yeah, there's uncomfirmed rumors that the US did something similar in Vietnam, with us shining lasers from aircraft to blind anyone inclined to stare up at them while using binoculars.
No SAM that I am aware of uses laser guidence. Unless one was modified that home in on the jet that way, but wouldn't it be simpler to use a heat seeking or radar homing missile?Originally Posted by Donnie B.
No, if it is actually approaching directly at you, then it doesn't move at all. That 587 feet in two seconds assumes that it is moving across your field of view, rather than towards you.Originally Posted by ff
Good points. But I still maintain that a laser blinding attack would have little chance of bringing a plane down, no matter where it occurred on the flight path.Originally Posted by Sever
It might have an effect if it was done during landing. As far as I know that is not done via autopilot.Originally Posted by Donnie B.