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That won't work. The problem starts at step 2. If the top layer isn't reflective, then as it "boils away" it will convert incoming energy from the laser into heat efficiently enough to destroy any reflective layer that might be under it.

Even if that weren't the case, you'd still have a problem at step 3, because your reflective surface will still absorb too much energy. An expensive mirror that's new, clean, and in perfect condition would still absorb 5% of the energy hitting it in lab conditions. In the air, in combat conditions, coated with goo from the stealth paint that just got burned off of it, the reflective layer wouldn't last even a measurable fraction of a second.

Optical vs. radio is just a choice of wavelengths. Whatever wavelength you pick to be shiny, can be used to detect you. Whatever wavelength you choose to be "not shiny", can be used to destroy you.

I wish GP hadn't bothered to mention the problem of stealth, because it's diverting attention from the point that matters - no material of any sort can be kept sufficiently reflective under combat conditions that the laser wouldn't destroy it. So really, even whatever wavelength you pick to be shiny, can still be used to destroy you.

A couple comments here are focusing on stealth, that's not the big question.

There is not a single US Gen 2+ stealth aircraft engaged in Iraq/Afghanistan. F-117s have been retired, B-2 are not needed. The aircraft over there are relying on a variety of other IR countermeasures (tactics/flares/directed IR) to defeat threats.

TFA is talking about shooting down UAVs, which pose a unique problem because they are very small and can be made out of low-tech composite stealth materials like frickin balsa wood. That, combined with a naturally low IR signature because of their low performance envelope, make it hard to target then with traditional guided weapons (IR and Radar guided).

The key question, which TFA avoided giving details about, is what range they are talking about. If the range is = a 25mm chain gun, this system has little value yet, as if you can find it and track it, a turreted chain gun is already very deadly, the ballistics models aren't that hard to compute. But those weapons are also very easy to fly above.

If this laser has a range of, say, 8 miles (40,000-ish feet), then things could get interesting. Data that would also be important is how long the laser needs to stay on target, and how small the beam is. If the beam is 1" wide, and must stay on the same spot for 1/2 a second, it could be defeated by old-fashioned 'jinking' which would move the beam around and diffuse the heat. But if it's 1/100 second, then again, it's really deadly.

Finally (and then I'm done), this laser is really cool, but must be guided by something... at 40,000 feet (or at night), you'll need something better than a Mk 1 eyeball to find and track the target accurately enough, just like you do today, and that's where countermeasures could be applied.

But a really good EO/IR guidance system that can find/track targets up to 40,000 feet on a clear day at night and a laser that can kill in 1/100" second (or close), and you've got a game-changing technology, forcing aircraft to hope for cloudy days.

Moderators: Parent may not understand the answer to his/her question, but that doesn't make parent a troll. WTF?

Parent: The mirror won't reflect 90% for very long. Not long enough for it to matter where the reflected energy goes, I expect. Perhaps collateral damage to other mirrors in the area; or, more seriously, I suppose it could damage the vision of anyone who was looking at the target from the wrong angle.