Right… I’m saying that an airfoil without angle of attack on a glider will plummet, and a flat plate with angle of attack will glide, because air won’t move faster over the top surface of the wing just because the path is longer - instead, angle of attack causes the air on the underside of the wing to slow down, and the air on the top of the wing is not slowed down (in the reference frame of the aircraft).
Flat plate wings are not preferred because there is turbulent flow induced by its movement, not because it doesn’t provide enough lift.
All I said was that it’s a point of some contention.
I’m just gonna go with NASA on this one:
There are many explanations for the generation of lift found in encyclopedias, in basic physics textbooks, and on Web sites. Unfortunately, many of the explanations are misleading and incorrect. Theories on the generation of lift have become a source of great controversy and a topic for heated arguments.
Lift occurs when a flow of gas is turned by a solid object. The flow is turned in one direction, and the lift is generated in the opposite direction, according to Newtons Third Law of action and reaction. Because air is a gas and the molecules are free to move about, any solid surface can deflect a flow. For an airfoil, both the upper and lower surfaces contribute to the flow turning. Neglecting the upper surface’s part in turning the flow leads to an incorrect theory of lift.
I think the two of you are having different arguments together.
You’re saying it’s a contributing factor and they’re saying it’s not the cause. Both of these things can be true.
We are taught in school that planes can fly because of the shape of the wing. That isn’t necessarily true even if it does have influence. It can happen without the wing shape. It may happen more effectively with it, but that wasn’t the claim.
I’m not sure I agree with you a hundred percent on your police work, there, Lou.
The science textbook deep state has been trying to teach you for Decades that air flows faster over the top of an airplane wing because the path over the top is longer, and that generates lower pressure, and therefore lift. It’s always been nonsense! Airplane wings generate lift by directly, unambiguously pushing air down, by being angled relative to the incoming air stream (called an angle of attack). This is why completely flat wings on balsa wood gliders and paper airplanes function perfectly well.
Bernoulli has nothing to do with it!
The claim I see here is not that the Bernoulli effect isn’t the primary source of lift, but that it isn’t involved at all. They double down later saying that airfoils are used over flat wings exclusively to combat turbulence.
And my claim was simply that there has been some debate on the topic among experts, because there has.
Right… I’m saying that an airfoil without angle of attack on a glider will plummet, and a flat plate with angle of attack will glide, because air won’t move faster over the top surface of the wing just because the path is longer - instead, angle of attack causes the air on the underside of the wing to slow down, and the air on the top of the wing is not slowed down (in the reference frame of the aircraft).
Flat plate wings are not preferred because there is turbulent flow induced by its movement, not because it doesn’t provide enough lift.
All I said was that it’s a point of some contention.
I’m just gonna go with NASA on this one:
I think the two of you are having different arguments together.
You’re saying it’s a contributing factor and they’re saying it’s not the cause. Both of these things can be true.
We are taught in school that planes can fly because of the shape of the wing. That isn’t necessarily true even if it does have influence. It can happen without the wing shape. It may happen more effectively with it, but that wasn’t the claim.
You can both be right here.
I’m not sure I agree with you a hundred percent on your police work, there, Lou.
The claim I see here is not that the Bernoulli effect isn’t the primary source of lift, but that it isn’t involved at all. They double down later saying that airfoils are used over flat wings exclusively to combat turbulence.
And my claim was simply that there has been some debate on the topic among experts, because there has.