It is all a matter of thrust and lift: the amount of thrust from the engines must overcome the drag force resisting motion, while the lifting force must counteract the effects of gravity. The wing is designed so that the air above the wing must cover a longer distance in the same time that the air below moves a shorter distance.
It is this imbalance of pressure above and below the wings that causes the plane to rise in altitude.. Where these clouds touch the airfoil they constitute the pressure difference that exerts lift on the airfoil. The wing pushes the air down, resulting in a downward turn of the airflow. In addition, there is an area of high pressure below the wing and a region of low pressure above. It is as if those four components collectively bring themselves into existence, and sustain themselves, by simultaneous acts of mutual creation and causation.
There seems to be a hint of magic in this synergy. And what causes this mutual, reciprocal, dynamic interaction? McLean says no: If the wing were at rest, no part of this cluster of mutually reinforcing activity would exist. But the fact that the wing is moving through the air, with each parcel affecting all of the others, brings these co-dependent elements into existence and sustains them throughout the flight.
Soon after the publication of Understanding Aerodynamics , McLean realized that he had not fully accounted for all the elements of aerodynamic lift, because he did not explain convincingly what causes the pressures on the wing to change from ambient.
In particular, his new argument introduces a mutual interaction at the flow field level so that the nonuniform pressure field is a result of an applied force, the downward force exerted on the air by the airfoil. There are reasons that it is difficult to produce a clear, simple and satisfactory account of aerodynamic lift. Some of the disputes regarding lift involve not the facts themselves but rather how those facts are to be interpreted, which may involve issues that are impossible to decide by experiment.
Nevertheless, there are at this point only a few outstanding matters that require explanation. Lift, as you will recall, is the result of the pressure differences between the top and bottom parts of an airfoil. We already have an acceptable explanation for what happens at the bottom part of an airfoil: the oncoming air pushes on the wing both vertically producing lift and horizontally producing drag.
The upward push exists in the form of higher pressure below the wing, and this higher pressure is a result of simple Newtonian action and reaction. Things are quite different at the top of the wing, however. A region of lower pressure exists there that is also part of the aerodynamic lifting force. We know from streamlines that the air above the wing adheres closely to the downward curvature of the airfoil. This is the physical mechanism which forces the parcels to move along the airfoil shape.
A slight partial vacuum remains to maintain the parcels in a curved path. This drawing away or pulling down of those air parcels from their neighboring parcels above is what creates the area of lower pressure atop the wing. But another effect also accompanies this action: the higher airflow speed atop the wing.
But as always, when it comes to explaining lift on a nontechnical level, another expert will have another answer. But he is correct in everything else. The problem is that there is no quick and easy explanation. Drela himself concedes that his explanation is unsatisfactory in some ways. So where does that leave us? In effect, right where we started: with John D. But the angry babies throw the planes into the baby pool a. Airplanes stay in the air because God wants them to.
If God doesn't want them in the sky they will fall. Airplanes fly because they're related to birds. Airplanes have wings, birds have wings, so they are related. Airplanes stay in the sky because people that have a lot of gas in their body get to fill the gas bottle.
Airplanes fly because an animal in the mountains somewhere has a big strong breath, and sometimes they crash because he has to eat or pee or poop. Airplanes stay in the sky because airplane meals do make people gassy and the, um, flatulence keeps the plane going. Planes stay in the sky because there are secret ghosts that pull the plane and keep the plane in the sky.
It is because of the pressure on the wings, and the engine also helps it fly. It is like the air, wings, and engine work together! Airplanes stay in the air because that's how the Wright brothers made them work. However, the world won't need planes someday because the Mokalla sisters will have made flying shoes!
Airplanes can't fly, so they slowly grow arms and reach as high as possible, then they gently float up and spy on people. The Wright brothers. That is all they will let me tell you. Ask them for more information. But between you and me, the passengers blow bubbles with gum to make their ears pop and they don't know it, but they make the plane fly. Airplanes stay in the sky by using the passengers' favorite things and placing them in a giant pot where the items get boiled and mixed together to make a mixture for the airplane stay in the sky.
Because the airplane has certain pressure and once it reaches the air, a nice witch casts a spell so that it floats in the sky. I just tried to calm you down.
The witch is evil! They use powerful engines and stuff on the wings to help it take off and land. The engines also help it go super duper fast like mph. First, they would fill up the engine so they would be safe. Then they would start going up in the sky, and go probably some 10, feet. And they would stay up in the sky for how much time they need to get there. As you can see, the blue recirculating flow - which creates drag - is much smaller in the airfoil profile.
As the air close to the surface flows over the top, it accelerates Venturi Effect and the pressure drops Bernoulli Effect.
If the angle gets too high, the pressure is not enough to keep it attached and we get a stalled wing. An airliner wing can produce around 7 kilopascals of lift in level flight.
Coupled with advances in material science and engine performance it's enough to keep the plane in the sky for anything up to 15 hours. How do planes stay in the air? Faculty of Science and Engineering.
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