BDS wrote:
There is an interesting article in Flying magazine by Peter Garrison that
talks about lift theory.

I thought that one of the most interesting points he made was that the
lift force generated by an airfoil is greater at the optimum angle of
attack than would be the force imparted to it if you were to move it
through the air perpendicular to the air flow at the same speed.

I first experienced this as a kid, sticking my hand out the car window with
the thumb as a leading edge, forming a crude airfoil.

When at the right shape and angle of attack, the lift is amazingly strong.
I always found it remarkable that when my hand was completely
perpendicular to the wind, the force didn't seem as strong.

Definitely a visceral lesson in lifting versus stalling.