1) Change params as RTL - disabled (standard)
autoTrim - (enabled), wind effects - (disabled)
2)Create DS with Difficulties params like here
https://community.bistudio.com/wiki/Arma_3_Difficulty_Menu
and forced AFM (in server.cfg)
3)Create EXPERT mission with helicopters (f.e coop5 Support stratis)
4)Start mission and try to start heli
5) AFM works well but autoTrim still enabled (it should be disabled by Server Side Difficulties Override) winds effects does not works untill you enable it.