Tucker Trim Problems

Currently I am trying to solve a trim problem with my Tucker Special. On the top of any outside square maneuver, when I pull down the outboard wing lifts up and the nose comes in. The outboard wing also Rolls up in any round maneuver. The kicker is it does not hinge in a hard pull out. Wings are level in level flight. Lap times are 5.0 on 64-foot lines measured center of plane to the handle. Turns are real close with no elevator offset.
Currently the best overall performance is with the forward lead out 1/8" behind the CG, 1/2 oz of wing tip weight and the CG is 6.2 inches forward of the trailing edge (hinge line).
Here's what I've tried so far:

Reducing wing tip weight until total loss of line tension at 45 deg. 1/4 oz at a time, also adding until a hinge was noticed in a hard pullout.

Moved lead outs from front to back 1/8" at a time, from 1/2 in front of CG to 3/4" rear of CG.

Added tail weight until plane was unstable in level flight.

Added nose weight until it was extremely difficult to turn.

Tweaking the out board flap up until the outboard wing was flying down in level flight.

I changed tip weight 4 times with each lead out change. Total of 16 flights

Nose weight helped over all line tension but not the problem.

Tail weight reduced line tension but did not help the problem.

The Rudder is air foiled per plans

The airframe was put together with a jig and all points are square, I checked them again today.

Here is the true effective wing and flap area as measured from the plane. Flaps are averaged over 8 points and wing is averaged over 12 points.

The inboard wing is 2" longer than the outboard

Inboard sq in-------- Outboard sq in
Wing-213.5--------------195.9
Flap--41.8---------------43.2

Total effective wing area is: 494.4 sq in
Using three points to measure the wing it comes to 535 sq in. (Root and tip / 2 X length)

Model weighs 37.0 oz (weighed at the Post Office)

Power would be???? The lines seem long for a Fox .35. Otherwise, try a "wart" on the outboard flap. Love the Tucker...how about posting a picture of it?
Sammy

Sammy;
I don't have one devoloped yet but it's been posted on #4853, "Photos from whitter narrows contest".
Power is good, turns a 10 X 6 BY&O or APC at 9150 in a strong 4-cycle. Good 4-2-4 break in the manuver. I have good line tenision until the turn. Line tension is good on over heads and four leaf. Bart and RJ have both had flights on it and agreed power was not a problem. RJ only had time for a couple of flights.

Thanks
Larry

Larry,

It is probably just operator trouble...want me to call the old time pattern for you anytime soon???

Bill Byles

OUCH!!!!!! , Bart does a much better job.

Isn't it wise to have the outboard flap slightly larger then the inboard. Paul does this on his Impact? Don't fry me on this one I'm just learning.

Larry,

Sounds like it has alot more sq.inches on the out board flap than usual. Why is that?

Gordie

Gordie:

I've taken that into thought. I've built a tab for the inboard to equal the two out, but thought I would get some feed back before I stared altering the plane, that's the reason for all the numbers.

My airplane does that, too. Should we start listening to Capt. Rabe?

Howard:

Yep, I think that would. Only problem is would it be classic legal? Could anyone answer that for me?

One thing I left out is I haven't flown it since the Night's Joust, Whittier Narrows. (I refinished the nose but, it weights the same). This problem was there before this but barely noticeable, now I'm fly in 15 deg hotter weather.

Here are tomorrow's changes:

Shorten lines 1.5 feet

Try a tab on the out board flap (Sammy and Bart Klapinski)

If all that fails then Tab on the inboard.

I would start over......double check CG/Lo position and work my way up....PW just paid me a visit and made me rethink my previous trim calc's. Have not yet tried his synopsis but after his only one flight observation and suggestions am inclined to think he is just about a genius!!!....What do ya think Gordie?

John:
I can do that, might have some hair left if I do. At this rate, won't be long before Klapinski has more hair than me.

Hey Gordie; think we could get your 4-Stroke in the Tucker?

Sammy:
The trim tab allowed me to carry more wing tip weight and helped the rolling problem and gave more line tension. I have no doubt you knew this already. As much as would like to keep it there it's as you say a wart. I was able to get it trimmed with out it. Thanks for your advice

Howard;
Thanks, 1/16 rudder offset and 1/4oz less wing tip weight took care of the main problem I went back to the 64 ft line length. Plane tracks good threw all the maneuvers now. Good over all line tension

John:
I changed the plane back to bench trim and checked all the CG's last night. I was surprised how far everything was off. Tell Paul thanks.

Thanks to everyone, even you Bill
Larry

>I would start over......double check CG/Lo position and work
>my way up....PW just paid me a visit and made me rethink my
>previous trim calc's. Have not yet tried his synopsis but
>after his only one flight observation and suggestions am
>inclined to think he is just about a genius!!!....What do ya
>think Gordie?
>
>John S.

Could you tell us more please?

Paul, could you watch my plane once too?

Funny about this thread, made the light come on. In the process of re-finishing my Omnium I adjusted the rudder for a little less offset. When I was putting in a few practice flights before leaving for Brodaks I noticed I could see the bottom of the wing in the triangle.

I hadn't noticed any rolling problems before and wasn't thinking about my changing the rudder until I read this thread. Rudder offset isn't necesarily a bad thing

The Tucker's trim problem are solved completely. I smooshed the plane in LA this weekend. The cause was the lead-outs hung up at take off. This plane was the only one I did not stagger the lead-outs on. During takeoff the planes wheels tracked in a crack in the pavement. This caused the plane to track inward and I lost line tension, when I got it back the clips had inter-locked. I was then a spectator. Teach me to mess with success.