i built the same plane, on mine the top half of the fuse. was not glued to the horizontal stab. witch let the vertical stab. move glued it everywhere i could get glue in wiped it of with some alcohol . worked great. i still had to add 1 1/2 oz. of weight to tail fly great and is very fast. the rudder is the part of the vertical stab. that moves . good luck lee p. s. i think this a good plane for 100 bucks