Aerodynamics of the Helicopter, by Gessow & Myers

[XXavier]

This interesting classic has been out of print by nearly 30 years, but is now available in the internet, for free...

https://b-ok.cc/s/?q=gessow

BTW, the site is a treasure trove... I'm not sure whether it's 100% legal or not, mais ça marche...

 

[kolibri282]

Great find, XXavier, thanks for sharing!
If someone complains, though, we would have to remove it.