Heavy Left wing

[n502pd]

OK, I have heavy left wing. Rudder and ele are both pretty well neutral and are not a concern here...I think!
I have tried to measure the flap droop from RH to LH flap, and found the RH flap about 1/8 inch lower than LH flap. Since I can not raise RH flap ..already against rear spar at inboard end, I attempted to lower LH flap 1/8 inch. Flap upper stops are not installed at this time, either side. Flew this evening and found that the wing is heavier that it was on the previous flight; eg, stronger tendancy to roll left and took a bit more holding right stick deflection.

Might this be the lack of flap upper stops not installed, miss riging of flaps, or wing install error of RH vs LH incidence? Aeileron and flap deflection angles are set per plans as well as I can.

Most problems I have heard of were that the RH wing was heavy.

What say you fellows who have gotten thru this problem? What was the fix. and how did you apply it if it was a rigging problem?

Thanks!

[rizzz]

I had a left heavy wing, quite bad actually, on my first flights it took significant force to keep the aircraft flying level.
I did a number of things to resolve the issue.

First thing I did was I got myself a couple of adjustable flap stops from Peter Anson, see here:
http://www.ansoneng.com/sample-page/pro ... lap-stops/

One of the problems is that here is significant slack in the flaps without stops in place and this makes fixing a heavy wing difficult, however, you cannot install the standard stops as you need to fix the heavy wing first.
These simple stops really help and are in my view and they are a much nicer “final” solution as well than the Sonex standard stops (which I never installed).

Anyway, after this I fixed the heavy wing by lowering the left flap, I had to get it down 3.5 turns if I remember correctly to get the aircraft to fly level, which is a lot.
The aircraft flew fine after this but what I did not like about that solution is that when flying, you see the left aileron always about 1/4" above the left flap while the right one is aligned nicely.
It’s a cosmetic issue but it drove me mad!

So what I did next was turn the left flap back 1.5 turns up which gave me a heavy left wing again, BUT, then I also put a (Velcro removable) solid trim tab below the right aileron.
So now I had a situation where the left flap was slightly low in flight and the right aileron was slightly high in flight so when I looked left/right, both ailerons were sitting about the same amount above the flap.
Not perfect but at least everything looks symmetrical in flight.

Then all I had to do was lower the ailerons very slightly to the point they align with the flaps again.
Now when I look left/right during flight the flaps and ailerons are perfectly aligned and everything looks as it should be, even though in reality, both the left flap and aileron sit slightly lower than the right flap and aileron but you would never be able to notice that.


Regarding the solid trim tab under the right aileron,
Like I said, it is just attached with a Velcro strip and I have various sizes so one advantage is that when I fly with a passenger I can use a slightly smaller one then when I fly alone (it really makes a difference in a Sonex), so I never have a heavy wing (anymore).

(Hope this explanation is sort of understandable)

[n502pd]

I do remember the velcro tab under the flap. and I may have to go that way as I am not a light weight pilot!! I also have seen the rear spar installed flap upper stops and am going to install those and indeed forgo the other up stops as shown on the plans. there is quite a bit of slop in the mechanism, I agree. And I do follow the sequence of flap and aileron adjustments, as I aslo have slight misallignment between ail and flap trailing edges.
Your explaination is quite clear and I am thankful for your response. I will post how it comes out.

Thanks much for the responses!!

Joe

[n502pd]

Update on heavy wing! I have discovered a root cause of my heavy left wing was related to a miss install of the RH flap hinge at the rear spar, having placed that half too far forward. This caused the RH flap to contact the aft spar at the inboard end about 18 inches when full up. The LH flap was further aft by 1/8 in, approx, and could come all the way up. I reinstalled a new hinge half on the RH flap and I am happy to report that adjustment is now complete with this evenings flight after making two test flights incrementally lowering the LH and raising the RH flap. The best I can tell is there is now about 1.5 deg deflection differences between the LH and RH in the stowed (up) position. There were no surprises when flaps were fully deployed either. Temporary up stops were installed, and the perminant ones can now be installed. Sirpeedee flew nearly hands off with a very very slow sort of roll to the left. I consider that my fat butt left of centerline!! My last adjustment was only 1/2 turn on both rod ends. I am very happy with these results.I shall endeavor to continue endevoring!:)

[jeff0196]

Great news! Thanks for sharing your experience and following up with it.