Thanks for the added info Fred. I flew a full scale Eurocoupe once. The rudder is tied into the yoke so there were no rudder pedals. Talk about a wierd feeling pushing on the floor boards and nothing. My flight instructor thought it was hysterical. thankyou for the duckerons graphic. It is awesome!
I thought if the rudders don´t work particulary well, why not try vectoring?
I know that many people tried vectoring the thrust component (motor itself) so that it will give some rudder effect, because often (mostly with jets) you have the problem that the rudders don´t have much effect.