Talk:Flap rudder

''In a two-part flap rudder, the aft part (the "flap") pivots back towards the centreline, thus producing a more hydrodynamic cross-section which increases lift and reduces the chance of stalling." Not true. Aft part folds away from the centerline and increases side thrust.  It uses a fully stabilized rudder w/ the axis running through the centerline of the plane of the rudder.