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YouTube, it's Cram. You most likely taught wrong about how airfoils produce lift. Don't
worry, it isn't completely wrong, but one part throws it in the wrong direction. You
were probably taught in school that an airfoil longer and curved on the top, and straight
on the bottom. Since the air has to travel a longer distance on the top, it has to move
faster. Due to Bernoulli's principle, there will be a larger space between the air particles,
creating a lower pressure than that on the bottom. Why does the air on top have to travel
faster you may ask? To meet the air on the bottom at the same time. Why does it have
to meet the air on the bottom at the same time? Well, that's the thing, it doesn't have
to. That is the problem. It doesn't have to meet the air on the bottom at the same time.
So even though most of those things are correct, that one fact throws this explanation in the
wrong direction. Some experiments actually show that the air on the top actually reaches
the other side FASTER than the air on the bottom does. What gives? Well, most wings/
airfoils are angled up. This means as the air hits it, it is deflected down and slightly
forward. This slows it down, but the air on top just curves down, and there is no speed
lost. Newton's third law states that every action has an equal and opposite reaction.
Since the air is deflected forward a bit forward, it creates drag. But its also deflected down,
creating LIFT. So why do you need Bernoulli's principle? The wright brothers used an airfoil
that pretty much flat, and they got off the ground. This is because us humans are all
about efficiency. Since this air on top travels faster already, why not put Bernoulli's principle
to use and create a lower pressure on top, creating MORE lift. And that is how an airfoil
produces lift, and why we don't have to worry whether or not our luggage will make it overseas.
How many airplanes have you been in before?