Sunday, February 20, 2005

Lasers and Airplanes (Part IV)

Over the past couple of months, I have put up a number of posts discussing how improbable it is that a laser could be used to cause an aircraft to crash by blinding its pilots.

You can find my earlier posts here, here, and here.

As I mentioned in my previous posts on this topic, to blind a pilot in one eye requires that the laser be shone directly into the pupil of the pilot's eye (a small target about the size of a pencil head) while the pilot is gazing directly at the beam source, while the terrorist cannot see the pilot's eye clearly (due to the cockpit glass), and while the airplane is moving. To cause a plane to crash requires the terrorist to repeat this amazing feat four times (once for each of the pilot's eyes, and one for each of the copilot's).

This week, there was some interesting news. It seems while the FBI was still in a panic over these myserious laser-terrorists, another government department (the US Department of Defense) has been developing a laser warning system to warn pilots they have entered restricted airspace. With this new system, which was scheduled to undergo its final test this past Friday, an aircraft that violates restricted airspace would have its cockpit lit up by alternating red and green laser light - much like the "terrorist" activity the FBI has been investigating lately. To quote the Defense Department, "the lasers are eye-safe and non-hazardous at all ranges."

The FBI really needs to give this laser-terrorist idea a rest. If this whole thing was such a plausible idea, we would have heard about it being used to crash airplanes in hotspot-areas like Iraq or the Palestinian Territories a long time ago. However, this idea is not only implausible, it is practically impossible.