Bernoulli's Principle, Busted?

The way I had it explained to me by an older CFI that seems to make sense is this. Bernoulli's Principle is correct, however its applied incorrectly. It has nothing to do with the wind being forced to travel farther thus causing it to speed up because it has to catch the air molecule on the bottom. The wind hits the wing at a certain point, and at that point it builds up an area of higher pressure (Think of a snow plow that builds up a lot of snow) and behind that point is an area of lower pressure, which in this case is on the top part of the wing. This causes the pressure differential on the wing, and this also causes the wind to speed up over the wing, not the other way around.
 
I'm a little thick, can someone explane how Magnus effect acts on a fixed wing for me?
 
knot4u said:
Bernoulli came up with that when or before airplanes were lucky to exceed 30 mph. An Old Guy told me once "A barn door will fly at the correct angle of attack". Attack seems like a mean word, I call bullying and will send a strongly worded letter.
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That's on the first page of the first chapter, The Wing is the Thing, in Stick and Rudder.
 
My brother is an Aeronautical Engineer and professor, so I asked him on his thoughts. He said that within the engineering community, there are lots of differing opinions.... circulation, Bernoulli, Coanda (can't forget that one), etc...

He said that even the smartest experts out there can't all agree 100% and there is still a lot left to exactly fully understand about aerodynamics. What they do know is how air interacts with different surfaces and how to manipulate airflow in order to create left, thrust, minimize drag, etc.
 
I once had a professor de-bunk Newtonian lift for me. I'm not saying he was 100% right, but it was rather compelling. The explanation of lift in the OP has some fairly severe holes.

I'm a believer of Bernoulli.
 
This is a chicken vs. egg argument. What comes first, the acceleration of air or the pressure drop? IMHO, both Bernoulli and Newton can explain flight, because they are merely theories that explain an observed phenomenon.
 
pete2800 said:
I once had a professor de-bunk Newtonian lift for me. I'm not saying he was 100% right, but it was rather compelling. The explanation of lift in the OP has some fairly severe holes.

I'm a believer of Bernoulli.
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The thing is aerodynamics is ALL Newtonian physics (with some thermodynamics/kinetic theory and mass conservation sprinkled there). The distinction created by people about Newton action-reaction vs Bernoulli is a ludicrous one, created from a misapplication of basic physics. The Bernoulli equation can be directly derived from the Navier-Stokes equations that come from Newtonian physics. In fact is in an energy conservation statement. If you think in terms of force (not energy ) then pressure differentials and shear stress distributions are the producers of lift and drag.
 
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charlie1017 said:
The thing is aerodynamics is ALL Newtonian physics (with some thermodynamics/kinetic theory and mass conservation sprinkled there). The distinction created by people about Newton action-reaction vs Bernoulli is a ludicrous one, created from a misapplication of basic physics. The Bernoulli equation can be directly derived from the Navier-Stokes equations that come from Newtonian physics. In fact is in an energy conservation statement. If you think in terms of force (not energy ) then pressure differentials and shear stress distributions are the producers of lift and drag.
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Now this, I can agree with. It's arguments that dismiss Bernoulli that I find objectionable.
 
Do you guys think that the low pressure above the wing holds the plane in the air as if it were tied to a ceiling? Yes. There's a low pressure above the wing. But when it's all said and done, the wing pushes down on air. The air holds it up. It's like that myth busters episode when they put the birds in the box and tried to see if the box got lighter when they were flying. It doesn't get lighter because they are pushing down in the air while in flight, and the air pushes down on the box.

It's not like Newtonian laws of physics don't apply to airplanes...
 
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