Pit-Viper 1

My Feedback: (12)

I am new to 3D-4D type planes, unless you count the Twist 40.. I recently acquired a Showtime 90 4D and am having problems getting it to balance..I think. According to the manual it states to balance it inverted, when I tried this it would sit level until you tip it in either direction and which point it will fall fairly fast rather than coming back to neutral. Now I'm not sure if this is a natural occurrence of this type plane or not. I am using the GP CG Machine and have it set at 7 7/16" from the leading edge. I am using a SPE26 and have both receiver/ign. batteries just behind the cockpit. Any help would be appreciated...


Thanks Shane

rmenke

My Feedback: (13)

Pit viper:

I don't trust the CG machine due to the ease of moving the measuring rods back and forth. Suggest you measure and mark the recommended CG location with a removable ink marker pen, and then use two short lingths of striping tape 1" or so and position it over the pen mark extending from the fuse side toward the wing tip as streight as possible. Now you should be able to position the feet of your CG machine at identical locations on both wings and visually confirm the location. Sounds like your machine is hanging up somewhere, maby the rudder. Should tip freely. Set the CG per tape location and remove from the machine. Now, use your finger tips at the tape. You should get the same results, or at least very close to the same results. Dub Jett uses two led pencils, with a larger pointed eraser. His wings are typically composit, would be a little hard on a 10 lb. balsa wing aircraft. ENJOY

Pit-Viper 1

My Feedback: (12)

Thanks alot, I will give it a shot. I talked to a buddy that had one of these and he said he had the same trouble balancing his. Said it did the same thing to him. I've used the CG machine for several planes and this is the first time I've had this problem. Thought maybe it was the mid wing design goofing with me. Trial and error, guess it can't all go smooth...

Thanks again,

Shane