Thanks for the replies guys. I have the 'trim' option in the 'mix' on. This function seems to work fine - ie if you adjust the tx trim for elevator both ele halves move the same amount. I have used the y with success on a different plane, but I read somewhere that you should be able to to plug the elevator servos into channel 2 and 7 and have them function together. Which they do - except when going back and forth between hi and lo rates. I have the have dual rate set at 50% for hi and lo rate on channel 2 and this allows the elevators to work fine, but no hi rate for 3d work.