Some people when they look up at the sky and see an airplane flying over wonder, how do airplanes fly? Well this article is for those people.
In the picture above, the black arrows represent the airflow over the wing, the solid purple arrows represent the different pressures caused by gravity, and lastly, the outlined purple arrow represents the lift generated by the wings airfoil. A plane sitting on the tarmac can't do anything lift-wise but when it taxis down to the runway, spools up its engines and gets going down the runway, the wings start generating lift and around the 150-200mph range the plane rotates into the air and you feel the g-forces press you into your seat as the airplane lifts into the air. There is a lot more going on than you think and almost all of it you can't see. In the picture above, you can see the air flowing around the wing and meeting again at the trailing edge of the wing. Because of the curved surface of the top of the wing, the air has to move faster over the top to keep up with the air on the bottom. Because of the fast moving air over the top, less down force is generated on the top of the wing. When this happens the pressure on the bottom of the wing becomes greater than the pressure on the top of the wing therefore lifting the wing and furthermore, lifting the airplane.
This is generally how planes fly. The horizontal stabalizer and the verticle stabalizer come into play as we'll but well save that for a more advanced article to come in the future.
Fly Fast!
Bailxs44
how do you think hang gliders work?
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basically the streamline illustration would look very similar.
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When you use a traditional airfoil, you also get Newtonian 'lift' with sudden, drastic changes in AoA and low speeds. Bernoulli lift is greatest when the air moving over the airfoil is fast enough to create that low pressure area above the foil.
In wind tunnel tests a flat plate just creates a huge, nasty pocket of turbulence at slight angles of attack, not the nice laminar flow that the Bernoulli effect needs to work it's magic.
If you want to really feel the difference, talk to a sailor. Water, being far more viscous is WAY less forgiving. A badly shaped rudder is awful and hard to manage. Working a flat rudder is how Popeyes got his massive forearms (That and life on the seas gets so very lonely... But mostly the bad rudder. I hope). But a proper NACA based foil on the rudder makes it wonderfully feather-light. All due to lift, but on a horizontal plane.
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