The explanation of LIFT by airplane wings?

Question

Being over 100 years after the Wright brothers' flight, why is the explanation of LIFT still so misunderstood, incorrectly explained in text books, and hotly argued among intelligent people, even pilots?

Answer 1

well there is low pressure on the top of a wing surface and high pressure at the bottom the difference of the two is lift. A pilots job is to manage the lift in the most efficient way as possible.

Answer 2

I dont understand why. Seems simple to me. Ever held a piece of paper with your finger tips, and put the hanging edge over the edge your holding? blow on the curved part, and the top goes up.

I dotn need more explanattion than that.

Answer 3

Newtonian principles state that lift is created by pushing the air down - true.

Bernoulli's theory enables us to calculate the pressure distribution on the airfoil surface correctly.

Circulation theory is consistent with observations of the air flow around the wing and makes it easy to calculate lift and lift distributions on three dimensional wings correctly.

The three theories are all correct and each provides value.  Seeing three different explanations for lift might lead some people to believe that two of them are wrong, but none of them are wrong.  Each adds value to our understanding and they are not in competition with each other.  Each is correct and each is used for a different purpose.

Why people argue about which is correct is beyond me.

Answer 4

because the conventional explanation is simple and easy to understand and to tell you the truth it is adequate. there is no requirement to solve it quantitatively. the majority of pilots are not adept at solving pure physics/math partial differential equations as they have not studied it at a high level and nor is it required for the job description. they just fly the plane and that is good enough dude.

Answer 5

It is misunderstood because educated people tend to explain it in terms of physics, which is difficult for most people to understand.  There is an easier way to understand this.  Here's a simple example.  When you were a kid, you probably put your arm out the car window.  With your palm flat and level, you don't have very much resistance. When you rotate your hand, with thumb up and pinky down, the wind pushes your are upward.  THAT'S IT !!  That is how lift is generated.

The air pressure under your hand was forcing it up.  There was no pressure over your hand. You could feel that.

Answer 6

You say that it is explained incorrectly, but you don't cite examples.  

I have seen numerous textbooks that explain it well.  Some of the answerers here have it wrong.  LIFT has nothing to do with the air that hits the bottom of the wing.  That is wind resistance.  That pressure helps the wing rise by increasing the difference in .  However, the lift will occur regardless.  An example of this is the experiment where you hold the piece of paper and blow across the top surface.  There is no additional pressure on the bottom, but the paper rises anyway because of the lift.

Answer 7

They/we don't really know, decades ago a room full of Cray super computers and tasked them with figuring out the flight of the bumblebee. The answer was does not compute. This made perfect sense to the military who promptly had the Grumman X29 built an aircraft that that was unflyable without the aid of computers, and fast-forward to the video of the F-22 proposing in over the runway while at trials for a belly landing  because of a computer failure .

Answer 8

Because it's complicated and most science teachers don't even know how it works so they tell kids the wrong thing.  Kids start off with a bad idea and it's harder to change it.

I'm a science geek, I read about aviation all the time, went through high school physics and calculus and I still didn't have the right answer until a couple of years ago.

Edited:  Wings generate lift with a combination of phsyics laws, everything from Bernoulis (spelling sorry) to Newtonian.  The largest portion of lift is Newtonian, the wing pushes the air out of the way and as the air molecules move away they create a low pressure vacuum that pulls the top of the wing up.  The other part is also that the bottom of the wing is almost always at an up angle so it deflects air downward, creating a high pressure zone and pushing the wing up.

Answer 9

The lift of a wing is equal to the change in momentum of the air it is diverting down. Momentum is the product of mass and velocity. The lift of a wing is proportional to the amount of air diverted down times the downward velocity of that air. Its that simple.

However...the problem is that we are missing a vital piece when we apply Bernoulli’s principle. We can calculate the pressures around the wing if we know the speed of the air over and under the wing, but how do we determine the speed?

Another fundamental shortcoming of the popular explanation is that it ignores the work that is done. Lift requires power (which is work per time).

Hence the understanding of this notion is a bit complex than it looks.

Answer 10

Allen told it right that is why to increase lift they increase the area of the wings by the use of flaps and slats (curvature included).

Answer 11

It is really simple:  

An airplane wing has a flat bottom and a curved top.

The distance from the front of the wing to the back is shorter on the bottom and longer on the top. (the shortest distance between 2 points is?)

At any speed the air moves faster over the top of the wing than the bottom, creating an area of low pressure under the wing, creating lift.

The faster you go, or the more aggressive the profile of the wing, the more lift is created, up to a certain point.

Answer 12

h**l people even thing there's a god.

Answer 13

because people are stupid and think it just doesn't mater