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With the recent increase in laser incidents reported by pilots, why don't airliner manufacturers shield airliner cockpit glass from lasers?

The Abrams tank is shielded, protecting the crew from lasers. Why could a similar process not be employed in airliners?

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    $\begingroup$ This is currently being researched and may be used in the future. Example: Airbus to test windscreen anti-laser film $\endgroup$ – mins Sep 14 '15 at 12:13
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    $\begingroup$ One thing to note is that people shining lasers at commercial aircraft cockpits is a relatively new problem. Second, it's important that things that pilots need to see are not filtered out by cockpit glass, so it is likely a bit of a challenge to design a glass or coating that stops laser light only and nothing else. $\endgroup$ – Todd Wilcox Sep 14 '15 at 14:56
  • $\begingroup$ The crew of an Abrams is inside a giant windowless metal box. The crew of an airliner needs giant windows to see out of. $\endgroup$ – Sean May 26 '18 at 0:32
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Money aside there is a bit of a practical reason as well. One of the simplest ways to protect against lasers is by filtering it using glass of a particular color, depending on the laser we are talking about red or green glass (and some other colors here and there as well). Generally they look something like this enter image description here

Coating an airplane windshield in glass of this tint, or a green tint would potentially impair the pilots ability to properly view PAPI or VASI lights which require red/white or red/green differentiation.

enter image description here

It would also cause the pilot to perceive all lights (during a night landing) differently.

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    $\begingroup$ I don't feel the researches look for colored (complementary color) filter attenuation. Glasses seem to exist with notch filters to cut the most usual laser frequencies, and remain otherwise neutral to spectrum. $\endgroup$ – mins Sep 14 '15 at 14:54
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    $\begingroup$ The issue remains that you would need to cut all possible laser light frequencies and still preserve not only color but light transmission. Remember the more filters you place the dimmer the field of view becomes which could present a problem at night as well even if its all color balanced. $\endgroup$ – Dave Sep 14 '15 at 15:27
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    $\begingroup$ @mins I have experience in notch filters: for a narrow band filter we are talking about 500 USD per square inch [not the unit I normally use!], but I have paid more than 5000 USD for an "unusual" block. A typical pair of laser goggles (with broadband blocking of green+IR) usually sets our lab back about 200 USD. The other problem is that, in our lab, the laser hazards are systematically characterized and we know exactly which goggles to put on when. But every few years a new lasing mechanism is commercialized at a new frequency, and you would always be recoating the cockpit windows. $\endgroup$ – Calchas Sep 14 '15 at 21:16
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    $\begingroup$ Yeah, this is the answer. It's not easy to just filter it out without knowing what frequency/frequencies you're concerned with and without significantly impairing the pilots' vision. Even if you know the exact frequencies, filters with enough rejection in the stop band to make laser illumination safe are probably also going to have a significant amount of attenuation outside the stop band. $\endgroup$ – reirab Sep 14 '15 at 21:43
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    $\begingroup$ Perhaps instead of a filter, we should just design airliners to fire a kilowatt-class laser back at the source. :) For repeat offenders, respond with this instead. $\endgroup$ – reirab Sep 14 '15 at 21:44
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Cynicism ensues.

Because it costs money, there is no regulation requiring it and airline companies probably do not feel it as being an issue because there still hasn't been a hull loss due to it (and thus do not look for it in the aircraft they buy).

It is said that aviation regulations are written in blood, so I am afraid that either we will see a hull loss somewhere, prompting EASA, FAA and similars to update the regulations, or we won't see shielded cockpits in the near future.

Note that I refer to "hull loss" for a reason, there have been already events leading to injuries.

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    $\begingroup$ to whom has downvoted, care to explain? $\endgroup$ – Federico Jul 25 '16 at 11:14
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In a laboratory environment, incidental exposure to lasers is prevented by wearing specialized glasses. This has been suggested as a possible solution to laser attacks on pilots. Most who point this out as a potential solution will, however, admit that it only works if you know the wavelength of the laser. You could go inquire on a different SE if you want to know more about laser safety. I would assume that if the FAA knew what the laser was they would also know who was operating it and stop them. As such, goggles are a long shot as a solution.

A promising emerging technology is electrochromics. In particular plasmonic polymer electrochromic materials could be installed either in a pair of goggles or in all cockpit windows. This poses its own issue though. The device would need to be automatic, since even milliseconds of exposure to some lasers is blinding. Imagine a pilot is on short final and his auto-electrochromic-goggles suddenly decide to block all light. Not good. you could instead fit the material to the cockpit windows. Then, in the case of a laser event, the pilot would need to react the same way as for unexpected IMC. this would mean a G/A if on final but would be much favorable to blindness. As an added benefit, once you've installed a laser weapon detector on the aircraft, you could give it the ability to trace the source of the laser beam to be relayed to law enforcement (or a targeting computer.) At any rate, we are talking many millions in R&D and production costs.

finally, this issue could be addressed by synthetic vision systems. If the pilot is flying on cameras he cannot be blinded. It is possible that a laser could be used to damage a camera but this could be more easily guarded against and I'm sure that synthetic vision will have many redundancies.

So if you are asking if you can walk into the store and buy a laser defeating device, probably not. If you want to buy several different pairs of cheap laser goggles on the off chance they are the right wavelength, it's probably better than nothing. At the moment, though, there is no comprehensive solution available. If you encounter a laser attack, do not look at it. Put your hand in front of your face and fly on instrument.

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