Is this wing flyable, or does it need to be rebuilt?

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Cass256

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Long story short, my RR3 was ground looped (something smacked the wingtip's leading edge, the ground or otherwise) before I got it & the left wing has "minor" damage.

wing 1.jpg
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20210429_112816.jpg
20210429_113035.jpg
20210429_113008.jpg

Sorry if there's any formatting issues, posting from my phone for the first time.

As you can see, two of the aluminum drag tubes are damaged (one bent, one broken at the rear spar) & the root rib & wingtip are warped. I'm confident I can replace the damaged drag tubes, but I'm not sure if I should even be flying this wing, the spars sweep backwards about 1° or 2° as well.

As far as I understand the history on the plane, it was ground looped & then put in a trailer, so I don't think it's flown since (thankfully). Everything else looks fine (other than some slight bends in the trailing edge piece) & I probably wouldn't've noticed the damage if I hadn't taken the fabric off.

Is it worth it to repair this wing? Would it still be airworthy? Or should I just build a new wing from scratch & not risk unseen spar damage?
 

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Victor Bravo

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Yes it is worth it to rebuild. You need to look at the struts to see if they were damaged in the incident, as well as the spar root attach fittings, the upper fuselage, etc.

Look for cracks or bows in the plywood ribs, and the glue joints between the rib capstrips and ribs.

Have someone help you twist the wing back and forth and listen for creaking.

You can clean up and re-glue the ribs onto the spars without much difficulty. Have powered sanding tools available to remove the JB Weld or Pro-Seal or whatever the gray glue is..

Be prepared to go to a slightly larger size rivet anywhere the rivets pulled out of the holes. A reamer or drill-reamer will make this a quick job.
 

Cass256

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Yeah, that's what I was worried about. When the fuselage & lift struts were sandblasted I inspected them thoroughly and they looked good. All of the damage is in the twist after the lift strut attach bracket.

I'm a little stuck on exactly how to rebuild the wing. If I need new spars, I'll need a bunch of one-off parts that aren't produced anymore (lift strut brackets, drag tubes) & I'm not sure I have the funds to ship anything that big to VT. :/
 

TFF

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If your pictures, the drag brace mounting would be the big deal areas. The drag brace is toast as you know, the rib is easy; brackets pulled out of the spar is going to determine what you got. Treat it all with suspension and make the important parts prove they are good or fixable, so you will be safe. You just have to peel it back and fix what you need to.
 

Victor Bravo

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You should not need new spars unless the existing spars are actually kinked or buckled.

Start by CAREFULLY grinding and sanding away all the dark gray glue anywhere it is cracked or separated. Chip it off with a chisel, grind it off with a Dremel tool, twist it off with pliers (without pulling the wood fibers apart), file it off WITHOUT filing grooves into any aluminum.

Run a string or straightedge along the front of the leading edge and see whether the leading edge tube has any actual permanent bend in it. If there is a bend, you can determine whether the bend can be fixed "in place" or whetheryou have to remove the spar from the ribs.

Even if you have to completely disassemble the entire wing down to the last glue joint and rivet, there's an 8 out of 10 chance you are still way ahead in terms of cost and time versus building a new wing.
 
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Cass256

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You should not need new spars unless the existing spars are actually kinked or buckled.

Start by CAREFULLY grinding and sanding away all the dark gray glue anywhere it is cracked or separated. Chip it off with a chisel, grind it off with a Dremel tool, twist it off with pliers (without pulling the wood fibers apart), file it off WITHOUT filing grooves into any aluminum.

Run a string or straightedge along the front of the leading edge and see whether the leading edge tube has any actual permanent bend in it. If there is a bend, you can determine whether the bend can be fixed "in place" or whetheryou have to remove the spar from the ribs.

Even if you have to completely disassemble the entire wing down to the last glue joint and rivet, there's an 8 out of 10 chance you are still way ahead in terms of cost and time versus building a new wing.
I hadn't thought of using a string, that's probably what I'll do to see if I can make a jig to re-bend the spars. I twisted the wing around with my brother yesterday and didn't hear any creaks thankfully, it looks like I'll be able to replace the tip & root ribs, drag wires, & go flying :D

Thanks for the input everyone, I'll post more about the repair in my project log most likely.
 
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