Reply #154: Thanks for the mathematical figures [View All]

[Art_from_Ark]

But I think we would have to use the distance shown by the hypoteneuse of the triangle formed by the airplane, fixed ground point (laser), and moving ground point immediately under the plane, rather than the distance between the ground and the plane. That would mean even greater divergence for your hypothetical laser beam, but the diameter of the beam would still be so small that the plane, at 250 knots/hour, would pass through the beam instantaneously and, as you noted, the beam would hardly be intensive enough at that distance to cause problems for a pilot's eye.