How does a wing REALLY work?

"How stuff works" is a great website. It's displayed in such a way that anyone can understand it, and they cover a wide array of topics.

The generally accepted theories (Bernoulli and Newton) work well individually or together. I like the equation that they use about the lift coefficient. Sometimes math is a wonderful means of understanding something very complex, and other times it's so confusing that you want to pull your hair out
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Nothing about lift on that website is incorrect. The FAA tries to dumb everything down so even the slightly retarded can pass checkrides. This reached its zenith when they issued the new Instrument Flying Handbook. Although the recent revision of the Pilot's Handbook of Aeronautical Knowledge seems to have reversed the trend somewhat. It looked good when I flipped through it.

If you want to learn more, I would recommend Aerodynamics for Naval Aviators. It has lots of math, but you can ignore most of it, and you will not truly have an understanding of what is going on until you read it.
 
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If you want to learn more, I would recommend Aerodynamics for Naval Aviators. It has lots of math, but you can ignore most of it, and you will not truly have an understanding of what is going on until you read it.

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Yeah, I've been meaning to buy that book. I hear "Flight Theory for Pilots" is also pretty cool. Funny, I never liked math until I started flying...
 
there's a book that's called "Flying the Wing" which is a fairly advanced read, if you're up for some pretty in-depth, detailed discussion about the creation of lift.
 
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Being but a lowly student pilot, I've alwyas been taught the standard FAA / King DVD explanation of how a wing works...but recently, I found this

http://travel.howstuffworks.com/airplane5.htm

Is this the truth that the Kings and the FAA isn't telling me?

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If you are really intrested, the study of advanced areodynamics, with all of it's formulas, charts, graphs, vectors, ectera can be facinating. For many people the simple Bernouli/Nweton explanation is suficent. Plane goes fast = wing makes lift = plane flys into the air.

I can give you the example of the study of medicine. My wife is studying to be a doctor and can give you all sorts of detailed information that you never knew (and plenty that you never wanted to know). I on the other hand know air goes in and out, blood goes round and round, and any variation of this is bad thing.
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As a profesional pilot most of us fall somewhere in the middle. My eyes glaze over when you pull out all the formulas and charts, but I want to have a good understanding about what forces are acting on my airplane. So I study and ask questions if I don't understand something.
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I will never design my own airplane, but I do plan on building a kit. When I do this, I need to be able to make informed decisions about what design to chose and where to modify that design. Vortex Generators for my RV-7 maybe?

The FAA explanation is the grade school version of areodynamics, it is up to you to continue to learn more about the many interconected aspects of aviation.
 
The way I always explained lift was that it was magic...

Just kidding.

From my understanding of lift, both from actual wind tunnel experiments and the book "Stick and Rudder" the airplane flies primarily because of angle of attack. Any object can have an angle of attack. Take your desk chair and throw it across the room. It generated lift, but not very effectively considering its shape. The airfoil design on airplanes is designed to maximize the amount of lift generated per wing area. Therefore we move large quantities of air over curved surfaces and their differential is how we determine the coefficient of lift which is directly related to our angle of attack. Most airplanes (like the 172, the Cherokee etc) have what's called Angle of Incidence which is another topic entirely but it's what creates lift on the takeoff roll prior to the assistance of back pressure. For a given airspeed, then a set angle of attack (chord line vs relative wind...straight down the runway in this case) we create lift in this manner. The air travelling over the top surface of the wing flows along a greater distance than the air under the bottom of the wing for a given static velocity. That decrease in velocity is the fundamental property of the Bernoulli theory. The decrease from static pressure along the top side of the wing versus the static pressure along the underside causes the airplane to rise into the air, assisted by the power vector coming off the prop to give rate of climb. It's all a very fine line though, because the generation of lift is predicated on smooth air flow over the wing. When we reach too high of an AoA, the wing can no longer generate lift and we stall. (That's bad).

The lift equation may make it all make more sense.

CL^2qS = Lift in Pounds where...
CL is the coefficient of lift (airfoil design, angle of attack)
q is the mass of air being accelerated over the wing
S is the surface area of the wing.

OK I'm done...I'm going back to my old answer.

Lift is created by magic.
 
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....The lift equation may make it all make more sense.

CL^2qS = Lift in Pounds where...
CL is the coefficient of lift (airfoil design, angle of attack)
q is the mass of air being accelerated over the wing
S is the surface area of the wing.
....

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Once again, the math does nothing to eulicidate or explain, only define....
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OK I'm done...I'm going back to my old answer.

Lift is created by magic.

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Now there is all the pilot really needs to know.
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Therefore we move large quantities of air over curved surfaces and their differential is how we determine the coefficient of lift which is directly related to our angle of attack. The air travelling over the top surface of the wing flows along a greater distance than the air under the bottom of the wing for a given static velocity. That decrease in velocity is the fundamental property of the Bernoulli theory. The decrease from static pressure along the top side of the wing versus the static pressure along the underside causes the airplane to rise into the air, assisted by the power vector coming off the prop to give rate of climb.


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What about airplanes with symmetrical wings?

What exactly causes the pressure drop above the wing?
 
Oh I thought we were talking simple aerodynamics...

It indeed remains magic

It has to do with angle of attack of the wing that creates lift in that case. Most airplanes have fairly "cambered" wings so the problem is negated, but airplanes with symetrical wings (as far as I know) are typically supersonic, low drag wings.

I don't have my Aerodyamics for Naval Aviators book right in front of me so don't hold me to that.
 
Tallboy has it. Wings fly by PFM.

Seriously, wings move air, by pushing it away from the side of the wing that does NOT have angle of attack. That's all you need to know. All of this stuff about camber is just misleading. (Camber, airfoil, etc are ways to make a wing efficient, to enhance it's abilities , but the wing still makes lift(force) by pushing air away.) If you take a PA28 with it's fairly high camber airfoil, and push from normal, S & L, upright flight, it will make lift down (against the camber). It wasn't the camber or the airfoil section (nor bernouilli) that made lift, it was action (moving air away from the wing in the upward direction) and re-action(wing moving away from the air it is displacing).

Alphaspeed
 
That's perfectly correct. It is not the airfoil shape at all...Hell throw a book through the air and it will create lift. It won't develop it efficiently by any means, but it too will have an AOA. Ah...Newtonian Theory it is a great thing...
 
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That's perfectly correct. It is not the airfoil shape at all...Hell throw a book through the air and it will create lift. It won't develop it efficiently by any means, but it too will have an AOA. Ah...Newtonian Theory it is a great thing...

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simply for the sake of discussion, if you threw a book in the air, would the book be producing lift or would it have had thrust acting on it in a vertical direction? i'm serious, too, i'm not trying to be a wise-@$$.
 
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simply for the sake of discussion, if you threw a book in the air, would the book be producing lift or would it have had thrust acting on it in a vertical direction? i'm serious, too, i'm not trying to be a wise-@$$

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Hmmm. I think it's more of a question b/w kinetic and potential energy than thrust/lift. For instance, say Mike Goulian enters a straight up climb, and shuts down the engine. He is no longer developing thrust from the engine, but his momentum still has kinetic energy carrying him upwards. As his kinetic energy bleeds off into potential energy (stored as altitude) he stops. At this point KE=0, and everything is potential energy. As he starts to fall backwards, the potential energy becomes kinetic energy again. Glider pilots have this stuff mastered. Me, I'm just glad I never have to take Physics again.
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