Does Bernoulli's principle really explain airplane lift?

Answer 1

Yes it does.

But there is more detail than what ground school books tell you and it is not based on the longer distance over the top of the wing compared to the bottom of the wing. In fact, the airflow does not meet at the same time at the trailing edge.

Symmetrical, inverted, and flat airfoils are perfectly capable of accelerating air over the top and decelerating (to a lesser degree) under them.

As for the Bernoulli vs Newton crap THEY ARE THE EXACT SAME THING!!! You can't have downwash without accelerating airflow and changing pressures.

For an explanation of why the air wants to accelerate over a wing, you need the Kutta-Zhukovsky theorem.

http://en.wikipedia.org/wiki/Kutta-Zhukovsky_theorem

Answer 2

Bernoulli and Newton used different math and different words to basically describe the same phenomena. As it relates to a wing, you can think of it like this: Bernoulli's creates the situation that allows Newton's law to create the force.

They really are not two seperate concepts though, they are the same thing. Airflow gets accelerated over the top of the wing, its pressure drops. As it flows off the back of the wing, its downwash creates an eqaul and opposite reactionthat we call lift. That lift vector is directed more or less upwards when it is combined with the drag that is produced by the low pressure behind the wing.

Answer 3

Yes it does. Think of the top of the wing as half of a cut-away section of a venturi tube.
The air flowing over the top of the wing accelerates, so to compensate the air loses pressure on the top surface of the wing & lift is created by the higher pressure flowing under the lower surface of the wing.

Answer 4

Yes

Answer 5

Not realy... Its some of the story, but theres also deflection of air by the airfoil. Something like Newtons 2nd or 3rd law, the one about equal but opposite actions...

Answer 6

In subsonic flow it is a good starting point.
There are other effects in play that get more dominant at higher compressibilities.

Answer 7

Depends.... If you are asked this question on a checkride oral, it sure does! :) On the other hand, if you look in Stick and Rudder, the explanation is a bit different.

Answer 8

Not exactly . . . Look at bitburger's link. You can also find a different take on it in "What Einstein Told His Barber".

Answer 9

Go to category "Cars & Transportation" then "Aircraft." This is for Air Travel.

Answer 10

It doesn't exactly. I have a link at work, and I'll post it tomorrow for you.

HERE IS THE LINK...

http://www.allstar.fiu.edu/aero/airflylvl3.htm