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Oldgeezer

Active Member
RV 9 QB fuselage / SB wings
wings temporarly mounted
ailerons mounted & aligned with tooling holes in each outboard rib by the alignment tool, flaps mounted. Now here is my problem. In order to get the right flap to align with the aileron, I had to lower the rear spar 3/16 " below a bubble level of zero and then the lower flap skin was up tight to the fuselage bottom. On the left wing using the same method and setting the wing incidence to match the right wing at mid span, I had a 3/4" gap between the flap bottom skin and fuselage. Incidence readings
right wing:Root 1/8" below level/midspan 3/16" below level/tip 3/16" below
left wing:1/8" below level/midspan 3/16" below level/tip zero level.
I have a 3/16" difference between the wing tips with the midspans equal
Questions: 1. will this wing incidence below zero require a change in the HS incidence setting?
2. How can I close the gap between the left flap and bottom fuselage skin?
3. will the 3/16" difference between the wing tips cause a heavy wing?
Thanks in advance
Oldgeezer
RV9A
 
Joggle the flap skin so it conforms to the fuselage. Align the wing tips to the ailerons when the ailerons are held in perfect trail.
 
Geez:
I'm building a 7 but the fuselage is about the same. The most important thing is to set the wing incidence correctly. If you set a different incidence than called for in the plans the airplane will cruise at a different deck angle, and probably slower. Yes, that would require setting a new incidence at the horizontal stab. You don't want that. Of secondary importance is the flap to fuselage fit. You should have some flap skin that overlaps the fuselage bottom that you can bend up or down to get a good fit, at least that is the way it is on the 7. If the wing incidence is correct and the flaps can't be made to fit, is it possible that you have built the flaps with a twist? I'd check that. If so, it should be possible to unbutton the flaps and rebuild them flat. Not a biggie. It sounds like maybe you have a little twist in your wings. Even that is not too terrible. Call Van's tomorrow and ask them. My guess is that you are OK. Good luck.
 
wing rigging update

I did level the fuselage laterally and longitudinally and set the sweep to zero. I also pulled the flaps and checked for twist - no twist found. It also appears that I have a slight washout on the left wing tip. I spoke to Bruce at Van's this morning and he said to forget trying to adjust the wings to accomodate the flaps. Set the wing incidence in accordance with the plans. Drill the rear spar bolt hole and then if needed, to make the flaps line up with the ailerons it is perfectly ok to either joggle the lower flap skin or cut it off completely. Thanks to those who replied.

Oldgeezer
RV9A
 
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