"The third problem provides the most decisive argument against regarding Bernoulli’s theorem as a complete account of lift: An airplane with a curved upper surf

"The third problem provides the most decisive argument against regarding Bernoulli’s theorem as a complete account of lift: An airplane with a curved upper surface is capable of flying inverted." Unfortunately, the author has fallen into the very trap that he is trying to explain. If you were to measure the velocity and pressure fields around the wing of an airplane flying inverted, you would find that they conform to Bernoulli (so long as the airplane is flying slowly enough that compressibility is not an issue, which is another source of complication.) What the author is doing here is to accept some bogus, hand-waving arguments for why the airflow velocity changes around the wing, such as the equal transit-time 'theory', which is, quite simply, false. To answer that question, you need the Navier-Stokes equations (which are the application of Newton's laws to a viscous fluid), or some realistic approximation. You may find this more informative: https://fermatslibrary.com/s/how-airplanes-fly-a-physical-description-of-lift https://fermatslibrary.com/s/how-airplanes-fly-a-physical-de...