Went flying sunday with my Mustang pts with the intentions of soloing, but a mid air put an end to my attempt. I had a collision with a giant 300L. Both planes survived and were landed safely. It appears that his wheel went across the right wing on my mustang. Im certain it would have sheared the wing off if i had not had the droops still on it. After inspecting the plane, I noticed the wing was cracked about an inch back from the leading edge. I just removed the covering to see what the damage was and it doesnt appear to be anything that wouldnt be fixable. My questions are these. Can I replace just a section of the leading edge, or is it advisable to replace the whole edge in one piece?? I also have 2 of the ribs inside that have cracks in them. They run with the grain. Would I be able to just CA these, or do they also need to be replaced? They are cracked in the center where the aileron servo wires run through them. I was thinking of doubling the ribs on the leading edge so I would have something to glue to. Would this throw the plane off balance much? It would only be 2 ribs that would be doubled. I hope im using the right terminoligy. Im new and trying to learn. Any suggestions would be appreciated. If its to big of a pain, I guess I could always buy a new wing set, but would really like to try and learn how to make the repairs myself.

Thanks

I would think that if you can mend the broken pieces together, and if they are clean (no oil or contamination) then they would easily CA together and be just fine. Same with the rib.

Others may have differing opinions about this, but the damage sounds minimal and should be easy enough to fix.

CGr.

That can easily be repaired - no need for a new wing.

And don''t worry about the balance. Any changes will be minimal

The ribs can be glued back together if the crack is clean and there are no parts missing. I wouldn''t double the ribs unless they are at the root. Ribs in the middle of the wing are used more for creating the curve then structural reinforcement. Plus, a good glue joint should be just as strong as the surrounding wood. Most people add too much weight because they just double up everything. I subscribe to the practice of removing and replacing material damaged to the point of no return rather than doubling. Don''t take off the whole leading edge as a new piece can be spliced in. Cut out the broken edges at a very sharp angle. Then cut out the replacement to fit. The sharp angled cuts will give much more surface area to glue and will be very strong. Use wood glue for the leading edge replacement. Sand the joint and you won''t ever be able to notice it.

Remember, never use CA to sheet the wing. The CA won't sand as quickly as the surrounding wood (even with a sanding bar) and you will have ripples where the joints are.

All of the repairs should be pretty easy. Can you take a picture of the damage so we can give a bit better advice on repairing??

Ken

I already cut away the strip behind the leading edge. It was pretty much shattered. It was right on one of the ribs and broke about an 1/8th of and inch off of it. I know that rib will need to be rebuilt. As for the other cracks in the ribs, im not sure if a photo will show much. I can still take some pics if you would like Ken. I value your advice as I have read several of your posts and know that you know your stuff. I feel I have the repair figured out, but curious as to how much of a bow the balsa will allow without cracking. I will try and post some pics to show what I have done. If any of you guys have ideas that would make the repairs easier, im all ears. I have no problems with taking advice from you guys who know what I want to learn.

Pictures would be a big help, then we could see exactly what needs to be done and we could give you several options as to how to fix it.

[img][/img][img][/img] Here are the pics you asked for. The rib with the top chipped out of it is where the impact was centered. the balsa across the top was shattered 2 inches to both sides. It had also broken out the brace behind it on the (root i believe) and it was in several pieces. All I have removed is the section across the leading edge. everything else is as it was when I removed the covering.

Piece of cake.

First, the crack in the rib ib picture 3 you can just glue - nothing fancy, just glue it. Thin CA will wick right in, or you can spread it like you''re doing in the picture and put a little medium CA or wood glue in it.

For the front of the rib, get a piece of balsa scrap and glue it along side the rib. Then sand it to shape. It won''t matter that it''s a fraction of an ince to one side or the other.

To re-do the sheeting, have a look at this:

[link=http://www.rcuniverse.com/magazine/article_display.cfm?article_id=98]Sheeting repair[/link]

Ok, these are actually some very simple repairs. For the rib that is cracked that has the cap strip on it (your last picture). Press down on the top of the cap strip to close the gap in the broken area and simply wick thin CA along the cracked line. Keep pressing down until the CA "kicks" and sets. For the other broken rib. Do you have the "chunk" that came out of it? If so simply glue it back in place with thin CA. If not, it''s still no big deal. Using sheet balsa cut a piece the length from the spar to the leading edge. Now place it along side a good rib and trace out the top curve of the rib. Cut along that line to get the same shape as the top of the rib. Now glue this piece in place along side the rib with the chunk missing out of it. Now re-sheet the area over that rib. Simple and your done. One thing to remember when doing repairs like this is that ribs are not a structural part of the wing. Meaning that they aren''t load bearing. The purpose of the rib is to maintain the shape of the airfoil. Many times people will over engineer repairs to a rib because they think it has to be strong, which just adds unneeded weight. All you need to do it put components in place that will maintain the shape of the wing.

Thanks for your input guys. I really appreciate it. I didnt think it would be a real difficult fix, but some advice from experience certainly doesnt hurt. I will get after it and hope to be in the air again soon. Hopefully the next post will be on my successful solo.

Is it just me, or is there a crack in the top spar visible in the first picture?

Nathan,
I don''t see a crack in the spar. I see a line just to the right of the damaged rib that looks like a crack, but if I look at picture #2 I can''t see that it''s gone across the spar. But it would be a good idea to double check the spar to make sure that there aren''t any cracks in it.

Ken

Oh, nevermind. It''s just the edge of the glue residue... carry on! [sm=red_smile.gif]