I have a new Great plains Reactor bipe that checks out for CG at least according to the book. But when I put it up all it wanst to do is climb (like its tail heavy). I have to give it about 10+ clicks of down elev to keep it on track. This is my first bipe so am I missing something [sm=48_48.gif]. Any help would be great.

Thanks Frank

Find out if it's actually tail heavy.

There are a couple of tests that show you whether or not a model is tail heavy. It beats guessing. BTW, tail heavy models usually have increased elevator effectiveness. And if a model is overly tail heavy, you'd have your hands full flying it. The pitch sensitivity would be excessive.

From what little you've described, it sounds like you might have a wing incidence problem. That's often the case with biplanes. Do you have any way to adjust the incidence of the top wing? The top wings are often the problem.

You may want to also check your engine thrust. If the engine is pointing up it needs to be shimmed down to even and maybe a little down thrust. Any of these item will make it fly like you say. If it is tail heavy just a a couple of ounces of lead to the nose and check it again. The wing incidence issue, as mentioned can be fixed with shims. The instruction manual should tell you want the correct incidences are and you do need a meter to check them. Good Luck, Dave

The wings are fixed and will not move so thats out, how would you check to see if the enhine is pointing up? Its a electrict that just bolted in, I could add a washer to the two top screws to change the thrust. I think that I will start with a few ounces of lead to the nose and see.

Nothing but rain today, Ill try tonight or Sunday.
Lots of great things to try,

Thanks, Frank

Does it do the same thing inverted? If it's climbing because of a CG problem it will climb even worse inverted. If it is a incidence problem it pull down when inverted.

David

I would roll it over inverted as well... if it is tail heavy it will climb......you want a bit of push on the elevator to hold altitude....what ever you're comfortable with.....if its a thrust or incidence problem then it will dive....