Thunderbird trim help

Trim help needed: New plane, need some trim help. Dumas Thunderbird, OS 46 LA, APC 12/4. ( I am the only c/l flyer in College Station, no local help ) Flies level upright, outboard wing slightly high inverted- ? add wing tip weight or use trim tab ? Main problem: when doing outside squares, first turn toward mother earth, line tension goes away, can barely make next turn to inverted without smacking the ground. Does the same on square loops and square eights. Seems to fly rest of pattern OK, for a new plane.( even outside round loops are OK ). I would like to figure this out before I do smack the ground.
Bragging time: Turned 50 yesterday, got a RO-Jett 40 from my wife and daughter. What a lucky man I am!!!

>Trim help needed: New plane, need some trim help. Dumas
>Thunderbird, OS 46 LA, APC 12/4. ( I am the only c/l flyer
>in College Station, no local help ) Flies level upright,
>outboard wing slightly high inverted- ? add wing tip weight
>or use trim tab ?

Yes. Both. Instead of adding a trim tab you can "tweak" the flaps slightly to even it out upright and inverted. Then you will probably need to add a bit of tip weight.

Question, did you do the differential flaps? (Inboard move more than outboard?) The assymetry on this plane is already too much, and if differential flaps are added that can really mess things up.

Main problem: when doing outside squares,
>first turn toward mother earth, line tension goes away, can
>barely make next turn to inverted without smacking the
>ground. Does the same on square loops and square eights.
>Seems to fly rest of pattern OK, for a new plane.( even
>outside round loops are OK ). I would like to figure this
>out before I do smack the ground.

Your above trim problems are probably the partial cause of your problem. But then check your alignment. Make sure that the hingelines are square with the fuselage and that the stab is level with the wing. Assuming that is done, then work with tip weight and leadout position.

What line length and lap speeds are you using? Some people try to fly too slow and that loses line tension right off the bat.

Just go slow and easy. Don't do anything stupid until you have things worked out.

Leonard, thanks.
I did not build plane with differential flaps, they move even.
I did build in a flap trim tab, weight box, and adj. leadout.
It flies so level upright I did not want to start trimming until I got some input.
Using 65' lines, 5.45 sec. laps.
Would taping hinge line on elev. help?
DRM
( also, I used CA hinges, they are still a little stiff, could this be part of the problem )

Shorter lines 60'
Where is the balance point? Lead outs should be behind that point 1/2"
Need to fly faster 5.1 would be better.
What Prop?
Weight of Plane?

Plane weight- 49 oz., APC 12/4
Will get plane to fly level inverted, work from there.
DRM

Hey Spit.....Did you get to go flying today????

Scott(like to help)Riese

BTW..my T-Bird 2 comes in at 38 oz Wore it out 700 Flights

Did not get to fly. Spent another day working on my mom's flooded house instead. FYI- I have been known to build heavy, thus the 46!!!

FLOOD!!! Not good Sorry to hear that.

17" of rain in one day resulted in 12" of water inside the house. After a lot of work by me and a few others, she was the first on the block to move back into her house. Now I can get back to flying, might even go fishing! Hope to get to fly T-bird late today or Tuesday, will keep you posted on progress. HEAT is the problem now, do not want to fry an engine, or myself, while trimming a plane. DRM

No one has mentioned tapeing the hinge lines yet! Do it! It will make a big difference on the effectiveness of your control surfaces. Also make sure your down line is behind the CG. And, shorten those lines at least three feet to get you into the 5.1 lap time range.

As Len says, more problems in one direction turn than the other, start first looking for warps. Trimming the wings to so it looks level gets you in the ballpark, but smallish warps can easily be there even though the plane looks like it flys level. You have to make sure that the plane is not rolling in during maneuvers.

Try just doing some 8's, both directions, and see if the plane gets light on the outside portion. If nothing shows in easy, large maneuvers, gradually pull them tighter and do them higher. I'm pretty sure you will quickly find that the plane tends to get light on outsides, no matter where you do them. That means a warp. If that doesn't happen you've got other problems like Len mentions- tip weight, alignment, or maybe gyro prop effects.

Update: 60 ft. lines, flap/elev. adjustment, lighter muffler, T-Bird is flying much better. Thanks to all! DRM

Super!!!