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DaveC426913
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Recently, I was discussing airfoils with a friend. I thought I was being clever and said "No, Bernoulli's Law isn't what's keeping it in the air - that's a fallacy. If it were Bernoulli's Law keeping it in the air, then airplanes would not be able to fly upside down. What keeps a plane in the air when flying upside down is the angle of attack."
He came back with "No, what keeps a plane in the air when flying upside down is the fact that planes that fly upside down are so overpowered that simply pointing the thrust in the desired direction (say, up) will cause the plane to go whereever the engine takes it, wings or no - and despite Bernoulli's Principle."
I had to concede right then and there.
So: can a plane fly upside down using airfoil-generated lift, as opposed to thrust-lift? Evidence?
He came back with "No, what keeps a plane in the air when flying upside down is the fact that planes that fly upside down are so overpowered that simply pointing the thrust in the desired direction (say, up) will cause the plane to go whereever the engine takes it, wings or no - and despite Bernoulli's Principle."
I had to concede right then and there.
So: can a plane fly upside down using airfoil-generated lift, as opposed to thrust-lift? Evidence?