Ray wrote:

Why do all fighters since the biplane era have low wings?

Because attackers will probably be approaching from either the same level or above -
it's difficult to make an effective attack from below. It's also important to be able
to see in the direction of a turn when you turn in to attack an opponent. And not all
fighters are/were low-winged; many were mid-winged aircraft.

Why do most military transports (C-130, C-17, C-5) have high wings, but all
airliners have low wings?

The wing spars have to pass through the fuselage. With a low-wing, that means a hump
in the floor. With a high-wing, that means a lwo ceiling at that point. Planes that
carry cargo would rather have a flat floor to ease loading. People, on the other
hand, will step over a hump in the floor and bang their heads on a drop in the
ceiling.

Why are a lot of cold weather/high altitude planes high wing?

Dunno about "cold weather" planes, but the high-altitude aircraft which come to my
mind are mid-wing aircraft; the U-2 and SR-71.

George Patterson
If you don't tell lies, you never have to remember what you said.