Mark Drella

Sympathize? I don't get it why it's so mysterious. You know, there's so many examples of phenomena which basically demonstrate lift in a very intuitive way.

Sympathize? I don't get it why it's so mysterious. You know, there's so many examples of phenomena which basically demonstrate lift in a very intuitive way.

Sympathize? I don't get it why it's so mysterious. You know, there's so many examples of phenomena which basically demonstrate lift in a very intuitive way.

Well, there's lots and lots of explanations. So, for example, I don't know if you've ever done this in your kid. You can kind of fly your hand, right, as you hold it out the car window.

Well, there's lots and lots of explanations. So, for example, I don't know if you've ever done this in your kid. You can kind of fly your hand, right, as you hold it out the car window.

Well, there's lots and lots of explanations. So, for example, I don't know if you've ever done this in your kid. You can kind of fly your hand, right, as you hold it out the car window.

You can let the air support the weight of your hand, right, if you angle it just right.

You can let the air support the weight of your hand, right, if you angle it just right.

You can let the air support the weight of your hand, right, if you angle it just right.

Right, on an air cushion. If you've got to angle it up just a little bit, let the air blow underneath, so to speak, it'll support the weight of your arm, right, of your forearm. That's basically what lift is, intuitively. Air moving past an object pushes on that object. I mean, why is that a mystery, right? And you see it lots of ways. For example... How does a water skier stay up?

Right, on an air cushion. If you've got to angle it up just a little bit, let the air blow underneath, so to speak, it'll support the weight of your arm, right, of your forearm. That's basically what lift is, intuitively. Air moving past an object pushes on that object. I mean, why is that a mystery, right? And you see it lots of ways. For example... How does a water skier stay up?

Right, on an air cushion. If you've got to angle it up just a little bit, let the air blow underneath, so to speak, it'll support the weight of your arm, right, of your forearm. That's basically what lift is, intuitively. Air moving past an object pushes on that object. I mean, why is that a mystery, right? And you see it lots of ways. For example... How does a water skier stay up?

Well, the water rushing past the water skier pushes up on the skis and keeps the skier above the water, right?

Well, the water rushing past the water skier pushes up on the skis and keeps the skier above the water, right?

Well, the water rushing past the water skier pushes up on the skis and keeps the skier above the water, right?

The equations of motion for that situation are the same as for an airplane. Based on basic physics, there is really not that much significant difference between water and air. They're both classified as fluids. Big difference is simply the density. You know, water is about 800 times more dense than air. But that's the only difference.

The equations of motion for that situation are the same as for an airplane. Based on basic physics, there is really not that much significant difference between water and air. They're both classified as fluids. Big difference is simply the density. You know, water is about 800 times more dense than air. But that's the only difference.

The equations of motion for that situation are the same as for an airplane. Based on basic physics, there is really not that much significant difference between water and air. They're both classified as fluids. Big difference is simply the density. You know, water is about 800 times more dense than air. But that's the only difference.

So, if you could visualize air going past an object moving through the air, or if you visualize a water moving past an object moving through the water, they literally look the same. So, for example, The Goodyear blimp is almost mathematically identical to a submarine.

So, if you could visualize air going past an object moving through the air, or if you visualize a water moving past an object moving through the water, they literally look the same. So, for example, The Goodyear blimp is almost mathematically identical to a submarine.