ShmoopTube

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ever have those great flying dreams? you know the ones we're floating

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around like a soap bubble is super easy? yeah lucky you [woman flies through the air]

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oh we usually dream it with dogs but back to flight. humans have been trying

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to fly for a long time. walking is cool and all but why don't we

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have wings and hollow skeletons like birds. well one guy spent a lot of time

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was pondering that question . guy talking about him right now we're talking about

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the other guy who spent a long time pondering that question. Leonardo da

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Vinci. don't know him well he was a famous Italian genius inventor pasta

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eater and painter of the Mona Lisa. in his spare time he drew designs for tons [painter with machines]

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of elaborate flying machines made out of leather and wood and a few hundred years

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later his dreams became reality. which isn't too long ago wait as far as dreams

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go. just imagine how long we'll have to wait to finally become dogs. in 1783 the

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first working hot-air balloon was able to lift people 80 feet into the air for

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about 10 minutes. and sure it couldn't be steered and yeah it could involve

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more than one or two people but a neat party trick. balloons and dirigibles are

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also called lighter than air flying machines. they

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float because the air inside the balloons isn't as dense as the air

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outside the balloons. flying you the machine that's heavier than air turned

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out to be a lot more complicated physics wise. think about it in comic books and [superman flies next to man flapping arms]

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awesome dreams flying is totally simple. we just float upwards by the reality

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getting something heavier than air to fly is no easy task.

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every object that flies has to deal with four forces: lift weight thrust and drag.

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the lift is the amount of oomph needed to overcome the object's weight and

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actually push it into the air. weight or gravity is the opposite of lift. it's the

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force that's continually trying to pull the object back to the ground or crash

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the plane. yeah he's gonna hate. right thrust is the

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force moving the object forward through the air. turns out if we don't have

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thrust we don't have lift. they need each other like buffalo wings need blue

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cheese dressing and don't argue us on that point just

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don't. drag is the opposite of thrust and it's just the effect of air pushing [yellow plane carries wings]

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against the object as it tries to fly. so in order to get to genuine flight people

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had to invent a machine that had enough thrust and lift to overcome the drag and

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weight. that required more powerful engines or thrust and very carefully

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designed wings or lift. so one of these carefully designed wings look like? well

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put it simply the tops of the airplane wings are slightly curved wide so that

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air passes more quickly above than below. because the air moves faster over the

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top part of the wing the air is actually exerting less pressure so the pressure

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on the bottom of the wing is stronger that means the air is actually pushing [plane takes off]

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the plane up. thanks for the assist there air. it's amazingly simple when we think

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about it but it took humanity centuries to really figure it out. and wasn't until

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1903 that people got smart about all the lift weight thrust drag stuff and

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managed to build a machine that would actually fly. and it took 2 high-end

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bicycle shop owners and Orville and Wilbur Wright to make it really happen.

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their first successful test flight in the sandy dunes of Kitty Hawk North

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Carolina changed the world even if it was for only 12 seconds. still impressive

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though we go to the beach for the whole day and don't get nearly as much done. [people lounge on beach]

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