Slight flap asymetry

[Chippster1]

I have owned my RV10 for ten years now. I did not build it
i have always noticed that I had a “heavy” left wing and needed to put considerable right aileron trim for straight and level and could never figure out why.
well, one day for no good reason I decided to move the flaps from reflex position to the 5 or so degree position at cruise speed.
When I did this the plane instantly rolled left! My conclusion is my flaps are not perfectly aligned( right flap is lower than left by a non visible amount)
my question is, how do you align the flaps if necessary?
Remember I did not build it
Any advice?

Ted Chipps
N498EC

 

[Kyle Boatright]

I have owned my RV10 for ten years now. I did not build it
i have always noticed that I had a “heavy” left wing and needed to put considerable right aileron trim for straight and level and could never figure out why.
well, one day for no good reason I decided to move the flaps from reflex position to the 5 or so degree position at cruise speed.
When I did this the plane instantly rolled left! My conclusion is my flaps are not perfectly aligned( right flap is lower than left by a non visible amount)
my question is, how do you align the flaps if necessary?
Remember I did not build it
Any advice?

Ted Chipps
N498EC

The flaps are individually adjustable by rotating the heim joints (AKA rod end bearings) which are part of the flap extension mechanism. The assembly (the "flap pushrod") is shown on figure 3, page 5 of section/chapter 44 in the assembly manual. You can lower the "high" flap by lengthening the rod assembly on that side or you can raise the low flap by shortening the rod assembly on the low flap's side. Your adjustment precision is 1/2 of a turn per heim joint, so you can get them very close. To do this work, you may need to remove (at least) the top wing/fuselage fairing on the side you seek to adjust, remove the bolt holding the pushrod to either the flap or the torque tube which is mounted to the fuselage, and lengthening or shortening the (appropriate) pushrod.

So look at the flap mechanism plans - part of the wing installation chapter (Ch 44) in the plans.

 

[BobTurner]

The flaps are individually adjustable by rotating the heim joints (AKA rod end bearings) which are part of the flap extension mechanism. The assembly (the "flap pushrod") is shown on figure 3, page 5 of section/chapter 44 in the assembly manual. You can lower the "high" flap by lengthening the rod assembly on that side or you can raise the low flap by shortening the rod assembly on the low flap's side. Your adjustment precision is 1/2 of a turn per heim joint, so you can get them very close. To do this work, you may need to remove (at least) the top wing/fuselage fairing on the side you seek to adjust, remove the bolt holding the pushrod to either the flap or the torque tube which is mounted to the fuselage, and lengthening or shortening the (appropriate) pushrod.

So look at the flap mechanism plans - part of the wing installation chapter (Ch 44) in the plans.

You really need to go thru the entire alignment procedure, flaps and ailerons. But here's a suggestion. (1) Flaps full up ('reflex') should be up agains the aft spar. (2) carefully center the ailerons, both wings. To do this you will need to lock the elevators level (neutral). Now, stand in front and near the end of the left wing, and sight down the back half of the wing and onto the ailerons. Is there a smooth transition onto the aileron, or a slight bump up? Or is there a slight drop down? Slightly up is preferred. Compare to the right wing. One source of 'heavy left wing' is that the left aileron is slightly too low (compare to right aileron). A 1/16" makes a big difference. To fix you'll need to remove the aileron, slot the mounting bracket(s) to move it higher, fit a pin or glue into the slot to make it a round hole where you want it, reinstall.

 

[BobTurner]

You really need to go thru the entire alignment procedure, flaps and ailerons. But here's a suggestion. (1) Flaps full up ('reflex') should be up agains the aft spar. (2) carefully center the ailerons, both wings. To do this you will need to lock the elevators level (neutral). Now, stand in front and near the end of the left wing, and sight down the back half of the wing and onto the ailerons. Is there a smooth transition onto the aileron, or a slight bump up? Or is there a slight drop down? Slightly up is preferred. Compare to the right wing. One source of 'heavy left wing' is that the left aileron is slightly too low (compare to right aileron). A 1/16" makes a big difference. To fix you'll need to remove the aileron, slot the mounting bracket(s) to move it higher, fit a pin or glue into the slot to make it a round hole where you want it, reinstall.

PS. Vans specifies flaps full up (reflex) or "in trail" (about 3 deg below reflex) are allowed at all airspeeds. But anything more comes with speed restrictions, be careful (not sure if your 5 deg flaps was below reflex or below in trail.)