Building the Tail Feathers In an attemp to keep the extremities light, it was decided that the tail surfaces of the model would be of built-up construction. Some carbon reinforcements were also added in order to maintain strength in the members. Twin tailbooms are to be used, in order to offset some of the torsional concerns that came up as a result of last year's experiences. Since the model must be easily transportable (from Canada no less), the tailbooms are removable at their attachement point to the wing center panel, and the elevator is removable as well.

Above Left: Sorry about the darkness of the photo, but all it was trying to show was the package that the carbon strip came in. The material is 1/4" wide in order to work with the balsa size that was chosen as strip material. Any black material in these photos is the carbon strip, which was laminated onto the balsa with C/A. Above Middle: Framing goes pretty quickly on the simple rudder and fin assembly, with the only real snag coming in adding a belcrank for the elevator actuator. The belcrank runs inside the fin, and it captured on either side with a 1/32" plywood plate. The bearing is a short length of brass  tube. The rudder servos will fit in the fins (sticking out slightly), but the elevator servo will be mounter in the center panel of the wing. A carbon pushrod from CST works the belcrank, and a smaller length of the material actuates the elevator from there onwards. All the servos in the model will be HS-85MG's.  Above Right: Here you can see the blind nuts added to the top of the fin. Small nylon bolts will thread into these in order to capture the elevator. The elevator sits on top of the fin on a 1/32" plywood plate, and can be shimmed if need to change the decalage angle.

Above Left: Here the left-hand rudder servo is being trial fit to it's mount. The servo well is lined with 1/64" plywood, and surrounded on all edges with 1/4" balsa stringers. The servo will ultimately be held in with a dab of epoxy, allowing for replacement should the need arise. The lead will be run down inside the boom, which should hopefully reduce it's tendancy to act as an antenna (long leads are prone to that). Above Middle: Here you can see how the belcrank is only added to one of the two vertical fins. Rudder servos will be added to both fins. Framing has begun on the second of two rudders.  Above Right: A finshed rudder, showing standard stringer construction. The bottom brace has an allowance for mounting the control horn. The tail surfaces will eventually be covered in transparent Ultracote, and all hinges made with the material to prevent air gaps in the hingeline.

Above Left: Here a fin is being trial fit to a boom. Note that the boom runs underneath the rudders to prevent them from being damaged in a tailstrike. Above Middle: Here is the beginnings of the horizontal stabilizer, which has a 1/2"x1.4" balsa spar which is capped in carbon. Here the spar material is being stripped from a sheet of 1/4" balsa. Right: Bracing proceeds much like with the vertical assemblies...

Above Left: ...and here's the completed stabilizer. The elevator is still to be built at this point, but it's area has not yet been decided. Check back later for details of the completed tail group.

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