Howard Hughes pressurized aircraft development

Used to anchor the calculation of how much water is in the atmosphere — Hughes pioneered flying above the clouds, which is why we know cloud-layer thicknesses. Sets up the "one percent times 10,000 feet" rough-magnitude estimation.

I once wondered — these storms come across the country, dumping all this rain. How much water is up there? If you start calculating the thickness of the atmosphere that has clouds — if you were a Howard Hughes fan, you would know this. Howard Hughes developed pressurized airplanes so they could fly above the clouds, so you wouldn't have to worry about the weather. You have to get to high enough altitudes that you have to have a pressurized aircraft. He was essentially one of the first people to try to build a pressurized aircraft. Before that, the little biplanes go up a few thousand feet, 5,000 feet, and when they had bad weather you couldn't fly. By going up to 10 or 15,000 feet, you can get above the clouds. Some clouds go to 40,000 feet. If you take 10,000 feet of space, and the humidity may only be one percent moisture in the air, one percent times 10,000 feet — that's a lot of rain. You can dump feet of water. Those clouds still got plenty of moisture when they come from the Pacific all the way to the Atlantic.

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