Quick Flight Director question
I know there is a very simple answer here but I'm struggling to find it...
Why is it that when you go visual to land on a precision approach (ILS), you leave the FD's on all the way to touchdown, but on a non-precision you are required to turn them off and take the bird? Surely if you are visual the events that transpired to get you there are irrelevant? What is the difference here? If you're visual you're visual! This is based on the A320 family.
Please can somebody point out the obvious to me!
Thanks