Davids comments were correct (as usual) The only thing he was wrong about was his comment about "Y" cords reversing the servo.:
Originally posted by David Cutler
(the Y branch does the reversing for you)
A standard "Y" cord does not reverse the servos. You do not WANT to reverse the servos for ailerons. In the pic below, you can see that all 3 servos are going the same way to achieve the desired results.