Re: Why don't wings have dimples?

In article <m6Jjg.6681$y%3.1096@xxxxxxxxxxxxxxxxxxxxxx>,
"Peter Dohm" <lefty133@xxxxxxxxxxxxx> wrote:

"Alan Baker" <alangbaker@xxxxxxxxx> wrote in message
news:alangbaker-4B0CFE.00084712062006@xxxxxxxxxxxxxxxxx
In article <1150069926.345327.79420@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>,
"Dancing Fingers" <bcl122@xxxxxxxxxxxx> wrote:

Hi all,
I always wanted to build my own airplane but the time and money has
eluded me. So I've decided to design and build my own recumbent trike,
with farings. This brings me to my question, if golf balls have
dimples, to help them sail further, why don't wings -- especially for
STOL aircraft? Would putting dimples in my faring reduce my wind
resistance?
Just curious.
Chris

First of all, golf balls have dimples because in order to create lift
they need to influence the air passing by them with the golf ball's
spin. The dimples help to make the air slow down beneath the ball and
speed up above it; creating downward flow.

I believe that you have the effect exactly backward. The spin, which should
only be significant using the more steeply pitched irons; slows the relative
speed over the "top" of the ball and causes it to remain attached longer,

No. It doesn't. Golf balls spin with a rotation such that the bottom is
moving forward and the top is moving rearward.

while the air flowing under the bottom breaks away more quickly, which would
result in a slight net lift. It also explains why a "slice" curves as it
does--which is why a smooth ball would have improved my game. :-(

Wings produce that downward flow with their shape.

Exactly.

Peter
.

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