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

Instruments are only aids for navigation. Instruments can be wrong, instruments can fail. If instruments were truly that good we would not need pilots, drivers, ship captains etc.

We still need the human element. Humans can see and think critically about things. Electronics cannot. They only give an objective picture of something, when they work correctly (which is most of the time).