Thanks for all your answers, it helps me a lot
I have checked the IPC and the AMM to better understand the whole tail rotor pitch control and now its okay i get it.
In a brochure of Robinson company, they explain that there is no maintenance to perform on rods... Is it true? Even no preflight checks?
Because I'm still wondering whether state of spherical bearings in rod ends will be still good after many Flight Hours (wear...). What are your opinions on that point?
Sorry if my English is not so good but I'm really interested in that topic