What a “Stall” is in aerodynamics and why it’s an emergency for airplanes

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What a “Stall” is in aerodynamics and why it’s an emergency for airplanes

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It’s a situation where a wing can no longer do its job, and can’t you know, keep the plane in the air, it should be very obvious why this is an incredibly dangerous scenario

as to why this happens, well air has to move smoothly over the wings to properly create lift, however in some situations, especially when at low speed and with the plane pitching up, the air can no longer flow smoothly, so the wings start producing turbulence and stop producing lift

A wing gains lift from the pressure difference between air flowing over the top and bottom of the wing, low pressure on top, high on the bottom. A stall is basically when the flow of air is disturbed or reduced to the point that the pressure difference isint enough to create lift.

Its an emergency because when the wing stalls, you stop flying and fall out of the air.

Plane wings work by taking force from the plane moving forward through the air, and turning it into force that pushes the plane upward. If the plane isn’t moving forward with enough force, then the wing won’t be able to keep it from falling

Planes operate on the principle that airflow over the wings generates lift, which keeps the plane in the air. A stall occurs when there is not enough airflow to provide enough lift to the plane; that means the plane can no longer maintain altitude and will begin to descend, potentially uncontrollably. If the plane simply noses over towards the ground, that might not be a huge issue.

However, if the plane falls straight down in whatever orientation it’s in, or falls down backwards, then there’s a very real, immediate risk that the dive is not recoverable. The plane is designed to be flown and controlled in forward-flight; all the control surfaces (like the rudders and elevators and ailerons) that let the pilot control the plane are only designed to work when the air is moving from front to back of the plane. If the air is moving from the back to the front, those controls may not operate correctly. If they don’t operate correctly, the pilot cannot control the plane and therefore cannot recover from the stall/dive, which means the plane **will** crash.

If the plane noses over, the pilot has the ability to recover the control of the plane. However, an uncontrolled dive can still be dangerous; as the plane flies faster and faster downwards, it will be harder for the control surfaces to operate, since they are pushing against the air to turn/twist the plane around. If the dive is too fast, the control surfaces might not have enough power to actually control the plane, and the plane will simply nosedive straight into the ground. The pilot must regain control of the plane as soon as possible to prevent the airspeed from building up so much that they permanently lose control over the plane.

A stall is a condition in which your wings no longer generate lift because airflow is disrupted over your wings. To generate lift you need air to flow with the win, when the flow separates you no longer have lift and the flight control surfaces on the wings no longer have an affect on the aircraft. This typically happens when your angle of attack is too high; that is the angle at which the aircraft’s nose is pointed up/down vs the angle at which the aircraft is traveling. e.g. when you are taking off or landing, the noise of the aircraft is going to be pointed up but the aircraft isn’t climbing at that steep of an angle.