Tip: Aileron Squeezing

One of the Val’s and my little secrets is that she has always had a slightly heavy left wing. It has never been a big deal, since it is easily handled with the electric aileron trim, but nevertheless, it’s just something we don’t talk about. You see, during Phase 1, the left wing heaviness was much more pronounced – enough so that I decided to fix it by squeezing the right aileron using the recommended techniques and tools – a hand seamer. Well, I taped up the jaws and worked my way down the aileron, and made the plane much more balanced – but when I looked down the trailing edge in the right light, I could see little dimples every five inches or so – the width of the jaws. Disgusted, I quit before I did any more damage, sent her off to the paint shop, and lived with the residual slight imbalance. Every time I saw that aileron in the right light, it reminded me…..

Well, tonight I found myself sitting on a stool in the hangar, “laying eyes” on the -3 project, trying to figure out what comes next. I was fiddling with a couple of three foot lengths of .063 angle stock, and for some reason, got to thinking about the Val’s ailerons. Instantly seeing what I had been missing for years, I grabbed a handful of C-clamps, taped the angles up to pad them and give them a little grip, and set them up on the trailing edge of the right aileron. When everything was snug, I gave every C-clamp a full turn. I removed it all, centered the aileron trim, and took a turn around the patch – and she flew hand’s off, wings level – at any speed - for the first time! I even noticed that the trailing edge dimples from the original hand seamer were much less noticeable.



So….if you are going to go about squeezing your ailerons, you might consider leaving the hand seamer in the drawer and pulling out some long flat pieces of angle and a bunch of clamps – it looks to me to be a much easier way to do a far better job!

Paul

Good to Know

Paul,
Thanks for the great tip on how to do this without scalloping the TE. Question for you. How heavy was the wing? I guess a good yardstick would be, how many gallons of fuel did you have to burn off to get it wings level? My -6 is left wing heavy also, and barring any other "smoking guns", I will likely try squeezing the TE.
Thanks!

jetjok said:

Paul,
Thanks for the great tip on how to do this without scalloping the TE. Question for you. How heavy was the wing? I guess a good yardstick would be, how many gallons of fuel did you have to burn off to get it wings level? My -6 is left wing heavy also, and barring any other "smoking guns", I will likely try squeezing the TE.
Thanks!

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With my 6A, the right wing was heavy enough, that I couldn't fully trim it out with my aileron trim...........which is servo controlled on the wing. That's quite a bit, but stick forces to keep it level were very light. I didn't even bother for a few months. Somewhere around eighteen inches of light squeezing on the left aileron put the plane in perfect balance with trim centered. The left aileron trailing edge was slightly thicker than the right.
I was going to tape a wedge underneath it, when I noticed.

L.Adamson --- RV6A

jetjok said:

Paul,
How heavy was the wing? I guess a good yardstick would be, how many gallons of fuel did you have to burn off to get it wings level?

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Oh, maybe five gallons? A little more than half an hour. The unbalanced stick force was on the order of ounces - just enough that if you weren't using autopilot, you noticed it. I am either generally maneuvering, or on autopilot, so it doesn't make a lot of difference operationally - just nice to have it straightened out.

Paul

Rivethead said:

But if you're really good this is how it's done.

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Unfortuantley, that is what I tried and messed up - little dimples at the end of each "bite". The nice thing about the long angle method is that youget no discontinuities. Works better for us mortals....

Thanks for the Tip

Paul,

The tip is much appreciated.

I don't know why it would be fruitful to tell you that what you did in the first place was more correct when you had better results with the second approach.

I appreciate your sharing your learning curve.

Yep ... I agree...

.... the clamped angle "thing" is a great idea and much appreciated.

Elegant and simple, Paul. Your clever technique is worthy of inclusion in the next "2* Years of the RV-ator."

Tip

Thanks Paul. My right wing is heavy. Will use your tip when I finish painting, torn apart right now.

Great tip. About 8 months too late for me, but I'll share it at the local Chapter meeting.

Ditto

Smokey ended up just a tad right wing-heavy. Like the Val, Paul, not enough to monkey with when the flying is maneuvering or on AP. However, those times when both tanks are full and you've just climbed and leveled out ... trimmed it for level flight ... and it begins a S-L-O-W roll to the right ...

Harrumph.

I did the hand-squeezer-thing once before, and don't think I caused any noticeable ripples, but I may use your technique after Grady gets done doing his magic next week ... if the rain ever stops around here ...

So the point here is to squeeze the lighter wing side, is that correct? And Paul, by the looks of the pic, it looks like you're squeezing evenly top and bottom on the trailing edge. How do you suppose this little bit of aerodynamic change affects the aileron? Is it killing a little lift here by doing that?

Or are you then grabbing a C clamp at each end of the long angle and giving the whole thing a twist in the desired direction to achieve what you want?

jdmunzell said:

So the point here is to squeeze the lighter wing side, is that correct? And Paul, by the looks of the pic, it looks like you're squeezing evenly top and bottom on the trailing edge. How do you suppose this little bit of aerodynamic change affects the aileron? Is it killing a little lift here by doing that?

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Actually squeezing the trailing edge "increases" the lift, thereby making the aileron "fly up". and lowering that wing.

thanks mel...

you are pure genius.

Only time will tell....

Thanks Paul for the tip. I just finished "assembling" my ailerons but I won't find out which wing is heavy until that first flight. Unless there is a way to minimize that during this part of the build phase. Suggestions?

snoopyflys said:

Thanks Paul for the tip. I just finished "assembling" my ailerons but I won't find out which wing is heavy until that first flight. Unless there is a way to minimize that during this part of the build phase. Suggestions?

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Wing heaviness is the result of the sum total of all the little airframe errors, so you won't know if you have a heavy side until you fly. Its not really about "fixing ailerons" - it is about using the ailerons to fix the overall airframe rig. You have to have SOME surprises in Phase 1....