Originally Posted by
WING7
How much lift is created by the upper surface and how much by the lower one?
From the AP3456 Manual of Flying:
Although most low speed aerofoils are similar in shape, each section is intended to give certain
specific aerodynamic characteristics. Therefore, there can be no such thing as a typical aerofoil
section or a typical aerofoil pressure distribution and it is only possible to discuss pressure
distributions around aerofoils in the broadest of general terms. So, in general, at conventional angles
of attack, compared with the free stream static pressure there is a pressure decrease over much of
the upper surface, a lesser decrease over much of the lower surface so that the greatest contribution
to overall lift comes from the upper surface