balance problem
 

Hey guys,

Finally got this plane to fly great. But I'm confused why it is flying good. I kept adding weight to the tail, until now it seems the CG is at 50% of the wing cord!!!

Here's the initial problem. It wanted to go to the ground hands off. Inverted and level, same thing, go to the ground. Fly in a banked turn, pulls to the ground. You would think add tail weight.

In a dive, with power, or not - flys straight. In a vertical climb, with power - flys straight.

With the weight, flys ok. Without the weight, pulls to the ground with/without power.

7 pounds, 900 sq in wing

Suggestions?

RE: balance problem
 

From the picture, I would guess that your tail volume is large enough that your CG needs to be at 50% cord.

RE: balance problem
 

Here's another pic. Tail is good size, but doesn't seem out of place.

RE: balance problem
 

Tail "volume ratio" is large enough to account for the cg position. at that cg you possibly have a lifting tail (like the telemaster). if it flys fine and dosen't balloon on landing, then there is no problem.

RE: balance problem
 

I don't understand "pulls to the ground". What inputs are you giving when it does that? If I had a plane that was diving I would just add up trim. Then I'd roll inverted and if it required a lot of down trim, the CG would have to go back.

Tail volume is length of tail arm/wing cord X stab area/wing area. I agree with others that the tail volume looks very large because the tail arm is so long and the wing chord is fairly narrow--it's an unusual bird. What is it?

Jim

RE: balance problem
 

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