How airplanes fly

18 11 18 - 19:24

By now I'm sure you've all seen that elementary school show: airfoil, airstream, Bernouli, pressure difference, lift. Boom, magic gone. However, there's much more to it than that.

Airfoil in airstream picture is a sideview of an airplane's wing. Have you ever asked yourself how does that lift look if you look at an airplane from the front or the rear? How is the lift distributed over the wing spanwise? How it should be distributed?

One very smart german engineer figured it all out back about 100 years ago. His name was Ludwig Prandtl and his work forms the basis of every aeronautical engineer's knowledge today. Prandtl's result was that elliptical lift distribution is the best for a given wing span and this was taken as a fact.

Until now.

During my childhood years flying my first model airplanes I was explained all about elliptic lift distribution, even before I fully understood what an ellipse is. Even then I remember being uneasy about it, but mostly due to "these people are way smarter than me, they know what they're doing". And I tried to live with that attitude.

Then some things happened that bought all those toughts and doubts back:

 
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