Originally Posted by
Brian Abraham
The link on the 727 says "to increase rudder effectiveness". As for fairing the rudder, would that not be accomplished by the feel and centering mechanism?
Thanks for all the answers. It appears that it is to increase the effectiveness of the rudder and used in the case of the 727 because the space for the rudder is quite small. At first glance it appears to be much smaller than a 737 rudder.
The anti-servo portion of the rudders deflect almost 40° more than the 27.5° deflection of the forward portion of the rudder. I guess a lot of rudder space is taken up by the horizontal stab. It is interesting to see the view of the rudders from the side and the angled top and bottom of the rudders. I don't know the reason why.
As for fairing the rudder after a power loss, if that means keeping the rudder in a position with no deflection, I would think the airstream would do that with actuators acting as gust dampers. I believe the feel and centering mechanism will provide a new neutral position which could be somewhat of a control surface deflection requiring hydraulic power. Not 100% sure though.