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RV12 roll right

Just getting my rv12 in the air after 4 years. I have an issue of it rolling to the right. Not noticeable at pattern speeds, but requires a fair amount of left force at cruising. I have tried 'pinching' the left aileron of couple of times. No help. Should I be adjusting the ailerons? High wing up or low wing down?
 
Just getting my rv12 in the air after 4 years. I have an issue of it rolling to the right. Not noticeable at pattern speeds, but requires a fair amount of left force at cruising. I have tried 'pinching' the left aileron of couple of times. No help. Should I be adjusting the ailerons? High wing up or low wing down?

Been working the same exact issue right Heavy Wing, except when full flaps are applied both sides are equal. I?m still working the issue. On my fourth test Flight.
 
Just getting my rv12 in the air after 4 years. I have an issue of it rolling to the right. Not noticeable at pattern speeds, but requires a fair amount of left force at cruising. I have tried 'pinching' the left aileron of couple of times. No help. Should I be adjusting the ailerons? High wing up or low wing down?

Adjusting ailerons up or down won?t help. They?ll just equilibrate in flight. Something more subtle. Check angle of attack both sides, compare aileron hinge lines?vertical heights, ...
 
I bought my 12 from original owner with 48TT. The airplane had a small trim tab fastened to the left flaperon with double-sided tape. It worked but the trim tab looked obnoxious and tape isn’t exactly structural. I removed the trim tab and the plane flew with a very heavy right wing.

I checked and adjusted the straightness of the upper wing skin that trails behind the spar and also squeezed the trailing edge of the flaperons. Neither solution fixed the problem.

What I did find extremely effective was changing the height of the flaperon pivots. Its been several years now, so I can’t remember exact adjustments, but basically what you want to do is raise flaperon pivot on one wing and lower pivot on the other wing. Perhaps start with ½ turn up on right wing and ½ turn down on left wing and test fly. Again, I can’t remember which flaperon I raised and lowered. No big thing – just note the change and test fly. First test flight will tell you if you’re adjusting in correct direction. If wing is heavier in flight then do opposite correction.

I believe I ended up changing pivot heights by one turn of the rod ends. One wing one-turn up and the other wing one-turn down. Plane now flies hands-off and ball is centered in cruise flight. Deploying flaps anywhere in the white arc is still hands-off level flight.


 
Behold..... The Omgomulator !

This can put a lot of pressure on the trailing edge so use it very sparingly. It took 3 flights on the first RV12 and 2 flights on the second RV12 to make it fly hands off wings level.

Make sure you take time to round the corners, dimensions can be seen, plumbers pliers applies the pressure. It needs small and multiple tiny squeezes, sight down the trailing edge and check for pillowing.

Also consider lateral loading - if you have a passenger and a full tank, it makes a difference !

Be careful !

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Just getting my rv12 in the air after 4 years. I have an issue of it rolling to the right. Not noticeable at pattern speeds, but requires a fair amount of left force at cruising. I have tried 'pinching' the left aileron of couple of times. No help. Should I be adjusting the ailerons? High wing up or low wing down?

Cable tensions
 
I bought my 12 from original owner with 48TT. The airplane had a small trim tab fastened to the left flaperon with double-sided tape. It worked but the trim tab looked obnoxious and tape isn?t exactly structural. I removed the trim tab and the plane flew with a very heavy right wing.

I checked and adjusted the straightness of the upper wing skin that trails behind the spar and also squeezed the trailing edge of the flaperons. Neither solution fixed the problem.

What I did find extremely effective was changing the height of the flaperon pivots. Its been several years now, so I can?t remember exact adjustments, but basically what you want to do is raise flaperon pivot on one wing and lower pivot on the other wing. Perhaps start with ? turn up on right wing and ? turn down on left wing and test fly. Again, I can?t remember which flaperon I raised and lowered. No big thing ? just note the change and test fly. First test flight will tell you if you?re adjusting in correct direction. If wing is heavier in flight then do opposite correction.

I believe I ended up changing pivot heights by one turn of the rod ends. One wing one-turn up and the other wing one-turn down. Plane now flies hands-off and ball is centered in cruise flight. Deploying flaps anywhere in the white arc is still hands-off level flight.


+1
Do this. Raising the pivot point makes that wing ?heavier?. It?s pretty sensitive.
 
It?s actually pretty difficult to get an accurate measurement from the skin to the center of the rod end bearing that the flaperon pivots on. I?ve addressed this on several wing heavy 12?s. You can start by just removing the pivot bolt in the center of the flaperon. When you remove the bolt, if the rod end bearing does not stay aligned with the bolt holes in the hinge bracket, thread the rod end bearing in or out to align them, stick the bolt back in and fly it. As you can see, your aileron spar will no longer be held in a slightly bent configuration. This might be the only correction you need. If the wing is still slightly heavy, proceed with threading the inboard and outboard rod end bearings in or out a 1/2 turn at a time until you?re satisfied. Remember to keep the bend out of the flaperon.
 
Lowering the aileron hinge points on the heavy wing of my RV7 did the trick for my plane.

This is different than adjusting the push pull rod length coming off the bellcrank. It does not affect equilibrium or centering of the ailerons when raising or lowering the hinge point.
 
Almost have the heavy wing gone!

Been working the same exact issue right Heavy Wing, except when full flaps are applied both sides are equal. I?m still working the issue. On my fourth test Flight.

Making good progress, almost have the heavy wing completely eliminated. A little more tweaking the light wing. For me this has been squeezing the trailing edge of the wing. I little bit more and I'm there.
 
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