![]() It is super critical for landing as you need to have higher the angle of attack the slower you fly and all planes essentially are driven as close to stall as possible during landing. The main job of an airfoil isn't to create a pressure difference, it is to create conditions for the air to be laminar at as wide range of speeds and angles of attack as possible to make the plane nicely behaving and possible to takeoff and land. This turbulent air not only ceases to provide lift, it also prevents the air from below the wing to be directed downwards efficiently. Rather than being nicely directed downward, it just dissipates a lot of energy in turbulent motion that is not directed in any particular direction. When you have a stall condition, what happens is that the air below the wing is still being compressed and directed downwards, but the air above the wing becomes turbulent and "unsticks" from the surface of the wing. Here, the drawing at the top of the page makes it clear: But there is actually even greater amount of air sucked down by the region of underpressure created above the wing and by the laminar flow directing it downward. In a normally flying airplane, the wing compresses and pushes an amount of air under its wing. But it is also not enough for the airplane to fly. Those can be thought as being sucked down behind the wing (if you look at it from the point of view of a stationary air mass, not from the point of view of the wing).Īnd the main role of the airfoil is to keep that mass of air behind the wing stuck to the airfoil at wide range of angles and speeds as possible, because a flat sheet is very poor at doing this. Part of the air is diverted by the lower portion of the wing, but the much larger portion of lift is generated by larger masses of air above and behind the wing. I am looking for a bigger, far away view of the wing and showing what happens to the air BEHIND the wing.īecause how the plane really works is as it flies forward, it diverts large masses of air downwards. Now I admit I only skimmed the article, and although the animations are beautiful, I am missing what really is key to understanding of what is happening. Which is almost total BS because planes can obviously fly inverted. And this somehow causes pressure difference due to Bernoulli law and this is what keeps the plane up. I think the shape of the airfoil of the wing is absolutely distracting and prevents people from understanding what is really happening.Įvery person who ever stuck a flat object outside the window of a moving car knows that you do not need a fancy shape to have lift.Īnd so many people are stuck thinking that the shape of the airfoil is responsible for the plane to be able to fly, supposedly because the air needs to run a longer way around the foil above the wing than below the wing. I wish every presentation on how planes fly started with an actual flat plane. The hows and whys of that are beyond my understanding of fluid dynamics, but its fun to think about how complicated it can get. Get it right and the spin makes the path more stable, but get it wrong, it becomes less stable. rifle bullets and American footballs), where the Magnus effect effects the rotating objects ability to continue to rotate parallel to the direction of travel. This is to say nothing about when the axis of rotation is predominantly parallel to the direction of travel (e.g. Knuckleballs are famously hard to throw because they have very little spin, but they are also notoriously hard to hit because the trajectory is so subject to the vagaries of airflow between pitcher and batter. This is why licking the baseball is against the rules.Ĭuriously, the rotation can also lend the ball's path greater stability against changing air currents/densities and crosswinds. ![]() You can even tune this behavior by making the surface of inconsistently "sticky" to the air, so flow of air is more or less affected by the objects rotation. ![]() fastballs are usually thrown in such a way as to "roll" backwards, which causes them to climb. Basically, to provide lift, the brick or ball or whatever would need to be "rolling" backards, like a wheel. The Magnus effect is super confusing to think about. ![]()
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