ELi5 Why are planes grounded when there is fog but they can fly through fog and clouds.

Question

I dont understand when they have control towers and such advanced technology why fog can ground planes. Not much is done by eyesight now surely?

In: Technology

Answer 1

Flying and landing are not the same thing. Flying involves working hard to stay far away anything. In that system, a cloud or fog isn’t a problem. Alas landing can’t work without touching the ground, gently. That gentile touching is hard to do when you can’t see the ground.