JAXAshby wrote in message
...
"Why does 2/3 of the lift come from the
upper surface?"

it doesn't.

Decades of aerodynamicists believe it does, based on the the
evidence of thousands of surface pressure measurements by a
variety of different methods, in flight and in wind tunnels.
They've designed aircraft and their structures, then flown them,
then tested them, based on this knowledge. Jax, I'm beginning to
believe you come from a different planet.

100% comes from the difference between the bottom and the top.

I'll go along with that self evident truth

obviously, the bottom is greater when the foil has lift.

Sure, the bottom has greater pressure than the top. You've just
said that. But your phrasing was designed to mislead people into
thinking that you'd said the 'bottom' contributed more lift than
the 'top' contributed. And I can't believe that's what you meant.

JimB