RE: Aerobird Challenger Advice?
You can find the details for the ProTail if you go to the HobbyZone.com site. If you go to the video section and look at the Aerobird Extreme videos, you will find two that show the pro tail. They used to have a step by step instruction of how to make the modification, but I couldn't find it the last time that I looked. You can contact them and ask about it.
I made a Pro Tail for my Aerobird Challenger as shown on the attached photo. Basically, you fill in the slots between the control surfaces and the stationary part of the tail with 5 minute epoxy, using packing tape to keep the epoxy in place. Then you add some packing tape (that has reinforcing in it) in both directions across the epoxied slots for extra reinforcement. You then cut new slots along the same line as the original slots, but from the hinge to the FRONT of the tail. Basically, the Pro Tail takes the entire tip of the tail and converts it from being stationary to being part of the control surface.