Recently, Happy Dog posted:

"Roger"
I really doubt a 5 Mw laser would cause a problem at a distance of
three miles. As I said previously, if it had been a theatrical
followspot, I doubt anyone would care much. It's the weird colour
of green that makes it
stand out.

You do have to be careful though. We sometimes use 30Mw lasers for
astronomical pointers on clear nights and you definitely do not want
to look into one of those. They cost a tad more (between $200 and
$300 USD) than the typical little one used for pointing as screens
and are a whole lot brighter. The green light also carries a bit
more energy than the red ones. But even at three miles it'd light
up most of the cockpit and wouldn't show as a moving spot inside.
I don't think the 30 Mw would do permanent damage at 3 miles, but
you'd need to turn up the cockpit lighting to read the instruments if
you looked directly at it.

You *might* see a bright flash. But it wouldn't likely have much
effect on vision. You need to get over 5Mw/cm before the eye can't
react quickly enough to avoid temporary blindness.

The difficulty that I'm having with this thread is that I haven't seen
mention of the windscreen. These are not optically transparent, and I
suspect that most would be sufficiently micro-scratched so that the laser
beam would be imaged on their surface and therefore diffused to the point
that retinal damage would be highly unlikely. However, I can imagine that
night vision may be affected by the glow, and that is not something one
would want to have happen on short final. I agree with Happy Dog's point
that someone using a follow spot would be far more detrimental, yet not
cause all this ruckus.

Regards,

Neil