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To: PilotDave

BTW... the reason ducks are hunted with a shotgun is that you can’t hit them with a 22. A laser is like a 22. One pencil lead diameter beam, trying to focus on an eyeball traveling at 150 MPH at 1000 feet. Not going to happen. The eye will absorb more energy from your cell phone than you could possibly transfer to it from a MW laser at 1000 feet.


6 posted on 05/27/2012 9:25:47 PM PDT by babygene (Figures don't lie, but liars can figure...)
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To: babygene

The laser illuminates the entire cockpit. It doesn’t need to directly enter the eye to ruin dark adaptation.


8 posted on 05/27/2012 9:31:45 PM PDT by Kirkwood (It's not a lie. It's a composite.)
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To: babygene

http://www.faa.gov/pilots/safety/pilotsafetybrochures/media/laser_hazards_web.pdf


15 posted on 05/27/2012 9:56:07 PM PDT by Kirkwood (It's not a lie. It's a composite.)
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To: babygene
BTW... the reason ducks are hunted with a shotgun is that you can’t hit them with a 22. A laser is like a 22. One pencil lead diameter beam, trying to focus on an eyeball traveling at 150 MPH at 1000 feet. Not going to happen. The eye will absorb more energy from your cell phone than you could possibly transfer to it from a MW laser at 1000 feet.

Ah, that all depends on what the target's trajectory is relative to your line of sight. If they are coincident, sighting is as accurate as for a motionless object. And furthermore, the radiation's damage is not based on total emission (microwave vs laser) as you state; it is energy density = milliwatts per square millimetre, and time of impingement that counts. The effectveness is also dependent because of the beam coherence (phase), I suppose.

Working with a Raman spectrophotometer whose exciting line was the green line delivered by an argon laser, the beam was capable of 300 mw and was very narrow. I could and did put a hole into the plastic of my ball-point pen with that beam. Its damaging power was vastly different -- smokin' hot -- than the radiated power density of a cell phone.

Better check your theory as relating to basic classical physics and see if wour suppositions hold up in this situation. I think not.

If a laser (or shoulder-fired missile aimed thereby?) is fired from the end of the runway on a landing aircraft using optical line-of-sight, seems as if it would be hard to miss. Dazzle or temporarily blind one of the drivers with a laser beam? Maybe. Bring the airframe down? No, not yet, at least.

Believe me, when a laser damages your eye, you feel it!

(As an aside, if you want to have a lot of fun with your cat, get it to chase the laser dot as it moves on the floor or wall. They find it irrisistibly fascinating. Just make sure the beam does not enter its eye --- that the animal is always moving across or away from you!!!)

20 posted on 05/28/2012 2:45:42 AM PDT by imardmd1 (from a former spectroscopist, and also a subject of laser peripheral iridotomy)
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To: babygene
A little further note:

The Myrtle Beach runway is almost exactly oriented North-South. So irradiation from the east would lend a little credence to your "shooting a duck" theory -- that is, it would take pretty good aiming coordination to keep the beam on-track with the cockpit. But one would not have to "lead" the target -- no time of transition with light -- not quite as difficult as with ducks -- just need a good scope. On landing or takeoff, its not as hard as, say, shooting woodcock or partridges. (They're up close, faster, and trickier that an aircraft taking off or landing.)

However, if you had flown MB as often as I used to, you would have noted that the civilian and military runways adjoin and were parallel. Therefore, lasers aimed toward the runway would have gotten the attention of the APs as well as the civilian cops. No wonder this is given a paragraph of warning in the local blatt. The perpetrator may yet find a visitation from the DHS, especially if there is a repetition of this incident. (The airbase was closed in 1993.)

The other posters also have got some good points. One is that I think Rayleigh scattering by the laser beam passing through the windshield would not be significant. In fact, the angle of inicidence might be low enough that a beam from the east would just bounce off the front windshield without entering the cabin. One would have to keep hitting the side window to catch the driver's eye. And at that stage, he's not likely to be scrutinizing anything but his forward path.

just supposin' --- (isn't this analyzing getting kind of boring??)

21 posted on 05/28/2012 4:00:21 AM PDT by imardmd1 (from a former spectroscopist, and also a subject of laser peripheral iridotomy)
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