Robbie
MegaDork
11/7/19 10:52 p.m.
While walking tonight using an umbrella, I noticed that umbrellas can generate an impressive amount of lift at relatively low air speeds. Then, like any normal person, I began to wonder if umbrellas were invented before airfoils. Surely they must've been?
But if the umbrella did come first, why did no one notice how good it was at flying?
i think it depends on what you consider an airfoil?
the history of umbrellas goes back a really long way:
https://en.m.wikipedia.org/wiki/Umbrella
it then again, so are the first kites....
https://en.m.wikipedia.org/wiki/Kite
and I think experiences with kites lead to an understanding of a flame plate set at an AoA would produce lift.
as for why people didn't use an umbrella for flight....
Ok, not really. Part of it is because birds fly... and people started studying their wing shapes. (as far as I remember). See: Otto Lilienthal
I think there's some other reasons, but I'd have to noodle about it some more.
Next thing you know Robbie is going to be spinning cylinders in the air and noticing that they don't fall vertically!
Kites are one of my go-to discussions of how you can take a simple device and get really complicated with its analysis. I had all the nieces and nephews (and my daughter) make small kites and compare them a few summers ago at the beach. Stability can be challenging.
Robbie said:
While walking tonight using an umbrella, I noticed that umbrellas can generate an impressive amount of lift at relatively low air speeds. Then, like any normal person, I began to wonder if umbrellas were invented before airfoils. Surely they must've been?
But if the umbrella did come first, why did no one notice how good it was at flying?
Anyone that's seen the pits when a gust of wind rolls buy, will know canopies also fly.
Johnny_at_NineLives said:
Robbie said:
While walking tonight using an umbrella, I noticed that umbrellas can generate an impressive amount of lift at relatively low air speeds. Then, like any normal person, I began to wonder if umbrellas were invented before airfoils. Surely they must've been?
But if the umbrella did come first, why did no one notice how good it was at flying?
Anyone that's seen the pits when a gust of wind rolls buy, will know canopies also fly.
Sailing vessels were depicted as early as 5500 BC, which means the airfoil is nearly 8,000 years old. A sail is, after all, a sideways oriented airfoil.