In article ,
TRUTH wrote:

Pooh Bear wrote in
:

Commercial pilots often have to fly in rather poorer weather where you
may not be able to see the ground, horizon, or even much in front of
your nose. That's why they have instrument ratings. The idea behind
flying 'on instruments' is about when you can't see where you're
going. The reaon for the FAA rules about mandatory use of 'IFR' (
instrument flight rules ) flight is essentially precautionary.

Do you know that this, in fact, is applicable for 757/767s ??

You might want to consider the fact that people have been flying planes
at 30,000+ feet for several decades now, and many of them didn't have
anything lie that we'd consider IFR equipment.

WWII bomber pilots routinely flew at 30-33,000 feet, navigating by
landmarks.