Bernoulli and Newton were both 17th century (or so) scientists and were trying to understand why stuff behaves like it does. And they did a good job progressing science. In fact, a lot of their principles have been used to teach science to people.
But after their deaths, science has moved on, and both have been proved wrong, either in generic cases or in corner cases.
As I understand it, the currently considered "good" explanation of air flow around a wing, and the resulting lift and drag, is based around an equilibrium equation involving five different factors (like pressure, temperature and speed) in some sort of integral. But that equation is very hard to visualize if you don't have an extremely good grasp of math, and is too hard to calculate by hand anyway. That's why we have computers and CFD.
So anything from the Lift Fairies, via the Equal Transit theory, to Newton (Impact Lift anyone?) to Bernoulli (high speed = low pressure) is essentially wrong to some degree. And is best used as an approximation of what happens only.
Last edited by BackPacker; 21st May 2012 at 12:33.