manfred_von_richthofen wrote:

First of all i want to say hi all of you because i am new here and i
wish that you accept my apologies about my mistakes.

I am currently studying aeronautics and i am very intrested in mechanic
of helicopters and helicopter aerodynamics. But while i was surfing on
net i realize that i can not find any single info about helicopter hub
systems? and how does that thing works. how can i find information
about these sysems? Are these secret infos?

pssst...

http://www.b-domke.de/AviationImages/Rotorhead.html