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. "Blow over the top of a piece of paper and it will rise up. It rises up for the same reasons as a wing does." ...answered May 9 '14 at 7:41 by GdD

No, it does not. This is a WAY TOO COMMON misconception. That effect is caused by entrainment.

It is so sad that there are thousands of papers, web pages, lesson plans and YouTube Videos (Steve Spangler and Dr. Carlson's ScienceTheater) that teach the incorrect "Longer path, equal transit time and fast air reduces pressure" urban legend of Bernoulli and/or lift.

Though rather belated, FOR THE OP's Question: The wing's downward push on the air under it is a good start. Pushing down on some bunch of air causes the wing to be pushed up. This is Newton #3 and what I call The Natural Phenomenon of "Paired Forces".

Though rather belated, FOR THE OP's Question: The wing's downward push on the air under it is a good start. Pushing down on some bunch of air causes the wing to be pushed up. This is Newton #3 and what I call The Natural Phenomenon of "Paired Forces".

No, it does not. This is a WAY TOO COMMON misconception. That is caused by entrainment.

No, it does not. This is a WAY TOO COMMON misconception. That effect is caused by entrainment.

However, scientists discovered that the air moving over the top must curve around and follow that upper surface and this (details pmitted) also causes more air to be pushed down and adds to the lift. Detail explaining why the upper surface effect occurs gets more complex and it must be well understood before attempting to explain it and only if necessary. (The "longer path" does not cause it to speed up. It has to do with accelerating air around a curve) The student can accept that there is more that they won't understand and can be satisfied by a partial, but correct, explanation.

I'm not sure where that climbing part is going, but it is always the relative motion of the wing through the air (called "Relative Wind") that is important, not the climb angle. I believe you refer to the "Angle of Attack" (AOA). This is the angle that the wing makes as it meets the relative eind. If the nose is pointed up, but it is flying more or less level, this is because more lift is needed, USUALLY at low speed, when airspeed, and therefore lift is lower. At some point, as the angle of the wing points up too far, the smooth flow of air OVER THE TOP turns turbulent. It swirls around instead of following the wing smoothly and this destroys that upper flow and a large part of the lift. This is called "stall". This is proof that it is not juswt the lower surface that produces lift, otherwise the loss of smooth flow over the top would be a 'don't care'.

However, scientists discovered that the air moving over the top must curve around and follow that upper surface and this (details omitted) also causes more air to be pushed down and adds to the lift. Detail explaining why the upper surface effect occurs gets more complex and it must be well understood before attempting to explain it and only if necessary. (The "longer path" does not cause it to speed up. It has to do with accelerating air around a curve) The student can accept that there is more that they won't understand and can be satisfied by a partial, but correct, explanation.

I'm not sure where that climbing part is going, but it is always the relative motion of the wing through the air (called "Relative Wind") that is important, not the climb angle. I believe you refer to the "Angle of Attack" (AOA). This is the angle that the wing makes as it meets the relative wind. If the nose is pointed up, but it is flying more or less level, this is because more lift is needed, USUALLY at low speed, when airspeed, and therefore lift is lower. At some point, as the angle of the wing points up too far, the smooth flow of air OVER THE TOP turns turbulent. It swirls around instead of following the wing smoothly and this destroys that upper flow and a large part of the lift. This is called "stall". This is proof that it is not juswt the lower surface that produces lift, otherwise the loss of smooth flow over the top would be a 'don't care'.