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Aileron Rigging Help

mulde35d

Well Known Member
Friend
So I installed the Flaps, Ailerons, and all associated push pull tubes & bellcranks before rigging the Ailerons IAW the manual and Jigs. The left aileron rigged precisely with both the outer edge W-00026 Jig seen here,
23-10-2.jpg

and the bellcrank W-730 jig seen here.
23-10-3.jpg

Once rigged the Aileron trailing edge lined up precisely with the Flap trailing edge that is sitting metal to metal on the rear wing spar as seen here.
23-10-4.jpg

Sounds perfect, looks good. After rigging the right wing in precisely the same manner (W-00026 jig and W-730 jig set just right), the Right Aileron trailing edge sits about 1/4" high from the flap trailing edge as seen here.
23-10-5.jpg

Since the flap trailing edge can't be raised (metal to metal contact) and Van's support is unavailable until Monday, what should be my next step to rig the right Aileron?

I could easily align the Aileron trailing edge with the Flap trailing edge, but then the exterior wing W-00026 jig will not align. I am tending to trust the jig, but don't believe I should have a 1/4" difference in the Aileron and Flap trailing edge. Both Ailerons and Flaps are straight as an arrow with no curve or twist (I verified with a digital level). Anyone run into this problem before. I want to make sure I get it fixed before starting the wingtips.
 
Do I understand this right that you are setting this on the wing stand and not the airplane? The pictures appear to be in the wing stand.

If so, then how do you know the flap is hitting the fues?

However and regardless, as I understand it and believe, the jig for the aileron are the primary point of reference. Once the ailerons have been set using the jig, that becomes the point of reference for the flap and wingtip.

Of course if there is an unusually large gap, then rechecking all would be good place to start as well as checking for any twist in the aileron and flap. It is not uncommon to have twist in these control surfaces which will cause such misalignment.
 
flap data

Do I understand this right that you are setting this on the wing stand and not the airplane? The pictures appear to be in the wing stand.

If so, then how do you know the flap is hitting the fues?

However and regardless, as I understand it and believe, the jig for the aileron are the primary point of reference. Once the ailerons have been set using the jig, that becomes the point of reference for the flap and wingtip.

Of course if there is an unusually large gap, then rechecking all would be good place to start as well as checking for any twist in the aileron and flap. It is not uncommon to have twist in these control surfaces which will cause such misalignment.

Yes I am rigging on the wing stand. The flap is sitting vertically on the rear spar as seen here. This is the metal to metal contact I am talking about and the reason the flap trailing edge can't go up anymore.
Flap-2.jpg


I have the exact same misalignment but on the left side, the right is spot on. I determined I have some twist in the flap. By looking where the top wing skin trailing edge covers the row of rivets in the flap it is easy to see this is not in the same spot sighting down the row of rivets. Both Vans and my inspector said to leave as is until I fly the plane and see if it may need correction. Both indicated not to align the aileron with the flap because this will cause the aileron and eventually the wing tip to be misaligned causing even bigger problems, even though visually it would look correct.

This is the row of rivet where the top skin covers the flap. The rivets maintain the same spacing all the way from the root to Aileron in regards to the top wing skin. That is why I am perplexed. If either the flap or aileron had some twist it would make sense, but they are dead straight.
Flap-1.jpg
 
Jon,
Thanks for the pix about the metal to metal part of the flap. Now I understand what you mean.

I believe a good way for checking any twist in aileron or flap is to put each part on dead flat surface and check all four corners to see if it seats flat on the surface, similar to a chair or table with possibly one short leg, to see if there is any play in it.
Another way to check would be with a straight edge when attached to the wing, first check the inner side while holding the flap in the same position to check the outboard side. If there is any twist or misalignment in the hinges, you will see a gap by using a straight edge on the wing extending to your control surface.

Hope this makes sense.
 
Easy

Jon,

How does that compare to the other flap? When my flaps are up all the way the trailing edge intersects those rivets right in the middle. Seems like maybe your right flap may not be up all the way.

Easy explanation, when I took the picture I had a piece of cardboard between the rear spar and flap to prevent vibration will moving the wings around on the cart. In reality the rivet line is almost perfectly matched with the top skin trailing edge when the cardboard is not installed.

I?ll remove the flap and check the twist again, but I am not joking when I say dead straight.
 
If the aileron is aligned to the wing-edge jig and the line of the aileron isn't in line with the flap fully retracted then that alone is the problem to solve. Where the pushrods are setup is important but not contributory to the alignment of the actual edges; that is all setup by the edge jig.

It is possible to have the edge jig a little off; it fits right over the top of a washer at the alignment hole and that slips a little if you aren't careful.

Also there is an old jig and a new jig. Old as in 5 years ago. The old jig is a little different because is didn't account for a reflexed up flap (I may not be completely accurate here but that's what I remember). I only have the new jig. Is there any chance you have a different jig on each side? You probably only have the new one, and used it on both sides. Just a thought.

I suppose there could be interference with flap retraction on the problem side. Carefully look for interference. The pulled rivets can interfere if they sit proud.
 
New jig

I appreciate the thought. The kit is only a year old so I imagine it is a new jig. Just one that is flipped over for use on the left and right wing. The left and right flap both intersect the top skin at the same place on the rivet lines, so flap interference is out. I have set the edge jig about 20 times, so slippage off the washer is out.

I tried to adjust the right flap a little by weighting the outboard edge, but I ended up imparting a small amount of twist into the flap as seen on the rivet line against the top skin, so I stopped doing that. I am going to call Van?s tech support tomorrow when they are back in the office.

I also had another RV 6 builder take a look, but nothing obvious is popping out to us. The only other possibility would be to rig both ailerons down an 1/8 inch to split the 1/4? gap in both wings instead of the total gap on the right wing.
 
I have a 3/16? mismatch on one of my ailerons when checking using the templates in the wing stand. My Aileron trail edge is also ?dead straight? but when I lay it on a flat surface.... a granite countertop....I can rock it about the same 3/16? as the mismatch when installed on the wing. My plan is to proceed ahead and see if I need to adjust the wing tip after I fly it for a while.
 
It is possible that you are fooling yourself about any twist in the surfaces. One way I tell is to look at the surface from some significant distance behind it, looking at the trailing edge. If you shift your position so that the line of the trailing edge intersects the "horizon line" of the control surface at about at the thickest point, you can tell if the trailing edge is parallel to the horizon line.

Another possibility to suggest, and bear in mind I am not very familiar with the -14 kit assembly, would be if the flap hinges were mounted to the wing a little too far forward. This would have the effect of deflecting the flap downward a little when the flap leading edge rests on the drag spar. It would only take a 1/16" shift in the flap hinge point to move the flap trailing edge down 1/4".
 
I have a 3/16? mismatch on one of my ailerons when checking using the templates in the wing stand. My Aileron trail edge is also ?dead straight? but when I lay it on a flat surface.... a granite countertop....I can rock it about the same 3/16? as the mismatch when installed on the wing. My plan is to proceed ahead and see if I need to adjust the wing tip after I fly it for a while.

As far as I know this is the realistic way of finding if there is a twist in a controlling surface. The line of rivets next to the trailing edge of the wing could be near dead on and yet have a twist.

Jon,
You have the correct Jig, one of the first thing I checked in your first picture. The new Jig has a small hole in it to indicate new vs. old.
 
Twist

Appreciate the additional insight. I?ll pull the flaps and ailerons and place them on a piece of granite countertop to check again. Last time I used benches, straight boards, and a digital level. Granite countertops are likely better than all 3 of those together.
 
follow up

Talked with builder assistance tonight (they were worn out from Osh), but they said if the flaps and ailerons have no twist (which they don't as confirmed by the granite countertop) then it is likely the rear spar / attachment points on the wings have a slight bit of twist. Unfortunately this was the final conclusion that I didn't want to hear, but the good news is that it isn't as big a deal as I thought. They recommended rigging with the Jig as I did and checking again after final installation of the wings on the aircraft. After the first flight they said I could play with the rigging to eliminate any roll and get them as close to even with the flaps as possible.

Unfortunately no smoking guns on this one, will have to wait a year until first flight to get to the final solution. Thanks to everyone who provided additional areas to check.
 
I had the same issue with my plane. I used the aileron jig for alignment and then rigged the flaps with the ailerons. I've been flying for 3 months with no heavy wing or rudder trim needed. Slow build fuse, quick build wings.

Mike
 
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