[dilawar]

> and airfoils also benefit from micro-roughness for lowest friction.

I thought this was known to some extent that smooth surfaces are not always the best e.g. golf balls have dimples on them? No?

[dilawar]

Never mind. I didn't read the article (paywalled) and someone in the comments below answered this exact point.

[bookofjoe]

https://archive.ph/YwAky

[zobzu]

dimples are used for stability and lift, not for friction reduction / low cx