Spar crack

[Champ Dreamer]

I have completed my right wing rebuild (through final paint) and have started on the left. The 63 year old spars look almost new ! However, the main spar has a crack from the outboard tip in about 2"-3". Undoubtedly due to some previous ground loop or hangar rash. I would appreciate any suggestions as to fixing it. If it where aluminum, I would simply stop drill and patch it, but I'm a little less familiar with wood. The crack is longitudinal.
Thanks a million !

Brian Walker

P.S. Still looking for a servicable C-85-12

[joea]

Brian,

Please look in AC43-13 for guideance on a repair of this type.

If its a crack in the outboard section of the spar you can repair it, usually with not too much problem.

The AC is downloadable from the FAA.gov site for free.

Joe A

[Champ Dreamer]

Thanks Joe,

I will download that. I am meeting with my IA tomorrow, and wanted to have a potential solution in hand.

Brian

[joea]

Brian,

This is a normal repair and if your IA is not familiar with things like this then pls let us know. There are a lot of Aeronca's out there in the field that have ground looped, dragged a tip and cracked spars like this. There are as well a lot of them that have done this and flown for years (sometimes tens of years) with no issue.

Let us know if we can help. Might even be someone out there with some extra spar stock that you could get to use.

Joe

[jkvincent]

Brian,
I just finished rebuilding my wings, my left rear spar was original (1946).
In 1962 it had a scarf repair similar to your spar damage (outboard foot or so),
after repair it flew 45+ years, actually, only changed it out because I replaced all 4.
Take a look at the Factory Spar drawing #5-146n, no repairs at or near the Strut attach point
and no repairs near the Butt and no repairs midway between Buttt and Strut attach point.
Fix it and Fly.
Jim

[joea]

Jim brings up an important point. You might find a lot of pieces spliced together on your spar. Aeronca did that on many airplanes, using up left over pieces to make one good spar.

What is shown in AC43.13 gives you limits on doing things like this. Aeronca did not have to follow these limits as they were the factory. Please do not open up the wing and see something that would not be legal under AC43.13 and think that you have to replace it just for that reason. Factory has a different set of rules than what we have to live under.

If you need the blueprint Jim mentions, I can email it to you or you can get it at Todd Trainors website.

[Champ Dreamer]

Thanks for all the advice. Joe, I don't know what I was thinking when I said I would download AC43-13. I have had a print copy for years. It has a hallowed spot in the magazine rack of the upstairs "library". The IA and I decided to inject some glue into the crack (it is only about 3" long) and then to tack and glue some 1/8" plywood on each side. Outta work!
Trying to get the wing ready for cover this week. Unheated hangar in COlo Spgs, and I probably won't see many more days this year that will be warm enough for dopin' and paintin'.

Brian