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Wing Security Questions

Jcurry

Well Known Member
Hi All,
I’m new to the forum but I’ve been a huge fan of RV’s since the mid 80’s.
I am interested in the RV12 and I know that there are a lot of them flying.
Even so, I’m having trouble wrapping my head around how the wings attach (Mostly the fwd and aft spar tabs) and I need some educating please. Thank you in advance.
1. Do the spar pins go through both wing main spars effectively making it 2 pins holding on each wing?
2. What keeps the wings from moving fore and aft (as grabbed by the wingtip) since the fwd and aft spar tabs slide in and are not pinned or bolted? Or do they move?
3. Since the fwd and aft spars are not pinned or bolted does this allow the main spar to flex in all directions at the wing root?
4. Since the fwd and aft spar tabs are not pinned or bolted do these areas show signs of chafing?
5. Has anyone experienced cracking on the fwd or aft spar tabs?

Thanks for your help.
 
The spar for each wing extends across to the opposite side of the fuselage, so both wings are held in by both pins. Those pins are pretty beefy, thick walled steel tubing, tightly fitted into bronze bushings in the fuse and wing spars. Zero play there. The forward and aft tabs are a close fit into recesses in the structure, so there's very little (if any) movement there. There's no flex or play to speak of - fore/aft play is supposed to be only a few thousandths. The wings are rigidly attached by the pins and prevented from moving in any direction by the tabs.

We never remove our wings other than for the condition inspection, and I don't know anyone who does it more often than that.
 
You can get Kit Assembly Instructions on a memory stick from Van's for $10, and go through all the plans with schematics to see the details, if you're a better visual learner than reader learner. That would answer any and all questions you might have about how a RV-12 goes together, and how everything works together. $10 is a pretty cheap investment in knowledge gained.

Thanks. Do you have to own a kit to be able to get the kit assembly instructions on a memory stick?
I looked all over Van’s website and I couldn’t find the the $10 memory stick.
I am trying to research as much as possible before I purchase.

Thanks again.
 
The spar for each wing extends across to the opposite side of the fuselage, so both wings are held in by both pins. Those pins are pretty beefy, thick walled steel tubing, tightly fitted into bronze bushings in the fuse and wing spars. Zero play there. The forward and aft tabs are a close fit into recesses in the structure, so there's very little (if any) movement there. There's no flex or play to speak of - fore/aft play is supposed to be only a few thousandths. The wings are rigidly attached by the pins and prevented from moving in any direction by the tabs.

We never remove our wings other than for the condition inspection, and I don't know anyone who does it more often than that.

Thank you Dale!
 
Van's Aircraft > Store > USB Flash Drive
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Thank you! Flash drive ordered.

I’m surprised.. I figured you would have to have a builder # and signed a waiver.. I had to before I ordered anything..:)

Concerning the wings, the wing spars are probably the thickest, most heavy single pieces of metal on the airplane, other than the engine.. I can’t begin to guess how much force would be required to fold up a spar vertically. I expect the ribs and sheet aluminum would fold way before the spars.
 
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The spar for each wing extends across to the opposite side of the fuselage, so both wings are held in by both pins. Those pins are pretty beefy, thick walled steel tubing, tightly fitted into bronze bushings in the fuse and wing spars. Zero play there. The forward and aft tabs are a close fit into recesses in the structure, so there's very little (if any) movement there. There's no flex or play to speak of - fore/aft play is supposed to be only a few thousandths. The wings are rigidly attached by the pins and prevented from moving in any direction by the tabs.

We never remove our wings other than for the condition inspection, and I don't know anyone who does it more often than that.


With removable wings it seems there would be a gap between the fuselage and the spar end of the wings that would cost a few knots of airspeed. Is there any sort of "gap filler" piece that fits between?
 
According to the plans, it's VA-204, which is K40-250 POLYURETHANE FOAM.
 

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Being sure that the wing skins are trimmed around their entire circumference to the gap specified in the KAI (3/16 in I think) Is very important for avoiding difficulty installing the wings.
 
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