Runway edge lights brief illumination before touchdown
Posted: Thu Mar 09, 2017 3:16 am
Hello all.
Having recently moved to PHX, I'm doing some spotting at PHX, and am observing something I'm not been aware of before.
When planes are on final, the red runway edge light illuminte briefly (I'd say when the aircraft reaches 100 ft), then turn off right before the plane reaches that point.
I assume this is being triggered by the planes at a certain point, guessing as part of the auto land/CAT system.
Naturally my question is what is the purpose of the lights, what is actually triggering them, and if not answered by the previous question, why don't the just stay on constantly?
Having recently moved to PHX, I'm doing some spotting at PHX, and am observing something I'm not been aware of before.
When planes are on final, the red runway edge light illuminte briefly (I'd say when the aircraft reaches 100 ft), then turn off right before the plane reaches that point.
I assume this is being triggered by the planes at a certain point, guessing as part of the auto land/CAT system.
Naturally my question is what is the purpose of the lights, what is actually triggering them, and if not answered by the previous question, why don't the just stay on constantly?
