Van's Air Force

The definitive Van's Aircraft support community! Buying, building or flying an RV? Join our exclusive family of mentors and enthusiasts!

heavy wing fix

rwarre

Well Known Member
Patron
Got serious about fixing my heavy left wing. Here's my plan, any advice is much appriciated. 1. Line up tooling holes on the wing and ailerons and measure the down angle of the outboard and inboard edges.(of the ailerons) Right now the angle of degrees is off by 6 degrees. So my plan would be to get new brackets and get the down angle both ailerons to match. Then fly it and see if there is a difference. Thanks
 
Got serious about fixing my heavy left wing. Here's my plan, any advice is much appriciated. 1. Line up tooling holes on the wing and ailerons and measure the down angle of the outboard and inboard edges.(of the ailerons) Right now the angle of degrees is off by 6 degrees. So my plan would be to get new brackets and get the down angle both ailerons to match. Then fly it and see if there is a difference. Thanks
Wait, what? The inboard edge and the outboard edge of *an* aileron are off by *6 degrees*? That's HUGE...and way wrong.
 
No the inboard and outboard edges are not off. I was talking about the angles of right and left ailerons.
This won’t fix a heavy wing; in flight the ailerons seek equilibrium, since they’re interconnected.
PS In measuring the 6 deg did you first lock the elevator in neutral?
With rv-10/14 (riveted aileron trailing edge) a heavy wing is often a slight difference in the vertical height of the hinge relative to the wing. With ‘folded’ trailing edges, slight differences in the fold are usually the cause.
 
This won’t fix a heavy wing; in flight the ailerons seek equilibrium, since they’re interconnected.
PS In measuring the 6 deg did you first lock the elevator in neutral?
With rv-10/14 (riveted aileron trailing edge) a heavy wing is often a slight difference in the vertical height of the hinge relative to the wing. With ‘folded’ trailing edges, slight differences in the fold are usually the cause.
This is actually an old wives tale and one I have proven many times over…when you shorten or lengthen the interconnecting rods, you can definitely affect roll within a small window…if for example you shortened both rods down to below the wing trailing edge, they don’t seek equilibrium….they induce drag and move the center of lift, forward…so if you have on aileron high…you should correct that with rigging on the ground…I have many times found an aileron mis-rigged and corrected it with re-rigging…now…when you use the trim bias spring aileron trim…you aren’t adjusting equilibrium…you are just increasing the load on the stick in one direction. Same thing with correcting out of rig conditions and the ailerons will tend to correct for small roll uneven moments. It won’t cure incorrectly formed skin, or mis-aligned mounting holes…or any of that.

Now if it’s a gross build issue…on the order of several degrees, where the stick is displaced….that’s much more accurate to Bob’s comment.

A minor trim issue is well covered elsewhere in the forum and pretty easily understood…but if you build it straight and rig it correctly…there’s shouldn’t be a big issue…the equilibrium you are referring to is the total component of lift, each wing is contributing so a significant roll, is one wing producing more than the other…
In the six…and I suspect most…as we burn fuel off one tank, you can induce a roll…and the ailerons aren’t seeking equillibrium…one wing is just making more lift than the other…which is why we displace the stick, or induce trim bias of the stick to keep it flying nice.
 

Here is another thread addressing the same issue. What -model are you flying?

Carl Froehlich here on VAF walked me through the numerous measurements necessary to diagnose a heavy wing.

My -7 left flap was made incorrectly and was .250 lower than the right flap. I am an A&P and not the builder. The builder mis-rigged the ailerons to make it fly less bad.
 
Back
Top