Aeronca champ Sitka wood side panel rot?

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Wingz4life

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Wingz4life7
Hi everyone,

I’m in the market for an Aeronca Champ. I found one that pretty much hits all the marks for the money and mission. Before I move further on the deal, I noticed on the side of the window there are wood stringers? which resemble armrests seem to be rotting near the back.

From what I read online, these are structural and can’t be easily replaced. I know the owner uses the plane on ski’s during the winter. So I’m thinking moisture builds up between heating the cabin and cool down. Aeronca owners , is this a big deal? Thank you!
 

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A Champ Guru I’m definitely not. However IIRC the only structural wood

I recall is the Wing Spars. Other wood components such as Stringers may be

important but not on the same level. Just about everything on aircraft of

that vintage can be repaired for for materials and labor. Hopefully

a Aeronca Ace will step up and advise if it even needs repair and is it a

“ Big Deal”.
 
Thanks for your thoughts madman. Im hoping they can be replaced with minimal cost and not considered as a major repair.
 
Thanks Pmanton,

Yes, that’s where they look to be rotting. The ~ 4 inch board and the 1 inch stringer. Wonder if either can be replaced without having to touch the fabric. If so, it will be a deal breaker as I’m topped out on what I can spend.
 
Since Aeronca concerns were brought up my #1 concern with the

Airframe is the Landing Gear Attach points wearing out due to lack

of lubrication. Easy 2 person task to check.

Raise wheel off floor by pushing up at strut wing attach points wearing out.

Other person move wheel fore-aft while observing attach point on fuselage.

Excess wear means some welding and fabric work. ‍
 
Thank you Magman!

Keep em coming folks, I’m here to learn and buy a mostly problem free first taildragger.
 
Wingz4life said:
...I’m topped out on what I can spend.
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This, along with your "mostly problem free first taildragger" is a bit concerning. I owned a wonderful 1965 Champion Citabria that was kept in great condition and passed a thorough pre-buy. It still lost a cylinder in flight and ultimately required about $6k of work at its first annual. These airplanes are old! Respectfully, if the purchase price of an aircraft exhausts your available aviation funds, it might be worth reevaluating your situation. I'd hate for you to end up with a paperweight when it turns out that the engine is unairworthy or a stringer/spar is cracked.
 
Thanks for your input Av,

I should have said, I’m topped out on what I’m willing to spend. I want to do as much of my homework as possible to limit any surprises that pop up within the first year. I own a warrior and understand things come up with these old birds.
 
Wingz4life said:
Thanks for your thoughts madman. Im hoping they can be replaced with minimal cost and not considered as a major repair.
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You're gonna need to research this a bit as repairs to longerons is a major repair. If you replace it with a factory/PMA part then its not a repair. If its a a former then its just a repair.

If you fabricate a longeron/former then it is back into major repair land as its a substitution.

Aeronca is owned by Magellen Aerospace. Maybe they have a support number for parts/tech ops.

I'll echo what others have said... if you blow your wad on a purchase and have nothing left over then you're gonna have a bad time. Although I do love me a Stintson 108 or Cessna 170 I'd NEVER, EVER consider owning one due to the FAA's retarded rules. E/AB is the only way I can afford to fly.
 
The Aeronca 7AC does not have wood longerons. It does have wood stringers that help form the shape of the fuselage. The only way to repair or replace these is to remove the covering.

It looks like the wood in the OP only needs a sanding and refinish. Tedious, but can be done.

The major concern I would have with a 7AC is the AD on the spars. It takes a bit of effort to perform this AD and if the previous annuals were of the $200 variety, you may want to do a extensive prebuy to make sure you don't have a serious problem lurking there.
 
Thanks Pf……

I apologize for my loose wording in my first post. I’m blessed to not have to worry about funds. I’m purchasing a taildragger for me while the kids are getting all their ratings. I have always wanted a vintage taildragger, but don’t need a carbon cub. So I’m looking for a cheap taildragger to satisfy my urge, which there are plenty to be found. I have a couple that have low smoh and new fabric. I know things come up with the older planes and I’ll have no trouble addressing them, but that doesn’t mean I like throwing money away when I could have prevented it by researching(asking owners, mechanics etc) for any gotchas.

If it involves removing fabric or major repairs, I move on. That’s why this forum is great. So thank you to those that have replied thus far!
 
Thanks Doc! That’s what I was looking for. In the picture to the right or pilots side looks to be pretty rotted , though the picture may make it tough to see. Going to ask the owner about it tonight.
 
Wingz4life said:
Thanks Doc! That’s what I was looking for. In the picture to the right or pilots side looks to be pretty rotted , though the picture may make it tough to see. Going to ask the owner about it tonight.
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OK.

What part of the country are you in?
 
Thanks, I agree! Just a little tough on the useful load. Need around 450#. I found 3 so far that have it and am leaning on a Bc12d, chief, champ……
 
Wingz4life said:
I want to do as much of my homework as possible to limit any surprises that pop up within the first year.
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Have the mechanic who would maintain this aircraft if you bought it take a look at those fairing strips. I'm not seeing the rot you describe. And as noted have him check the wing spars and struts. Regardless, any replacement of the wooden fuselage fairing strips will require fabric work.

pfarber said:
You're gonna need to research this a bit as repairs to longerons is a major repair. If you replace it with a factory/PMA part then its not a repair. If its a a former then its just a repair.
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The part doesn't determine whether its a repair, the work required does. And as mentioned, those are not longerons but fuselage fairing strips and are not load bearing members. Perhaps stick to your CFI bashing as you appear to have more experience with that.;)
 
Bell206 said:
Have the mechanic who would maintain this aircraft if you bought it take a look at those fairing strips. I'm not seeing the rot you describe. And as noted have him check the wing spars and struts.
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@Wingz4life The underlying assumption is as important as the statement itself…you DO have a mechanic who’s familiar with this kind of stuff, right?
 
Wingz4life said:
Thanks, I agree! Just a little tough on the useful load. Need around 450#. I found 3 so far that have it and am leaning on a Bc12d, chief, champ……
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I've flown all those and the Champ will be the most expensive and the roomiest. The Taylorcraft will be the fastest, and the Chief will have the worst adverse yaw. A 450 lb useful load on a Champ is at the top of range for a 7AC. The gross is 1220, and most I see are close to 800 pounds empty. Aeronca listed the empty weight as closer to 700 lb than 800, but my understanding is they basically measured the lightest one they could find and put that number on the paperwork for all of 'em.

And to your original question - those are stringers to hold the shape of the fuselage. They are not primary structure, but replacing them would be problematic because they contact the fabric. I'd refinish them in place, taking care to avoid touching the fabric. As has been said, the spar inspection is a big bugaboo with these. Bad spars mean buying and installing new spars, which means a complete disassembly of the wing. Then you're in the game of "while I'm in here" and all those ribs start looking old and worn, same with the leading edge, might as well bead blast and epoxy prime all of the steel components in the wings, etc. Then reassemble and recover. A serious winter project if you have to go there.
 
kyleb said:
I've flown all those and the Champ will be the most expensive and the roomiest. The Taylorcraft will be the fastest, and the Chief will have the worst adverse yaw. A 450 lb useful load on a Champ is at the top of range for a 7AC. The gross is 1220, and most I see are close to 800 pounds empty. Aeronca listed the empty weight as closer to 700 lb than 800, but my understanding is they basically measured the lightest one they could find and put that number on the paperwork for all of 'em.

And to your original question - those are stringers to hold the shape of the fuselage. They are not primary structure, but replacing them would be problematic because they contact the fabric. I'd refinish them in place, taking care to avoid touching the fabric. As has been said, the spar inspection is a big bugaboo with these. Bad spars mean buying and installing new spars, which means a complete disassembly of the wing. Then you're in the game of "while I'm in here" and all those ribs start looking old and worn, same with the leading edge, might as well bead blast and epoxy prime all of the steel components in the wings, etc. Then reassemble and recover. A serious winter project if you have to go there.
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Thanks Kaleb, great points!
 
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MauleSkinner said:
@Wingz4life The underlying assumption is as important as the statement itself…you DO have a mechanic who’s familiar with this kind of stuff, right?
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Sure I DO! One mechanics experience with taildraggers does not equal the experience of many. This is not my first rodeo buying an airplane. Online research is a fantastic tool that I use along with my mechanic, and I appreciate those that contribute vs those that judge.
 
Wingz4life said:
Sure I DO! One mechanics experience with taildraggers does not equal the experience of many. This is not my first rodeo buying an airplane. Online research is a fantastic tool that I use along with my mechanic, and I appreciate those that contribute vs those that judge.
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I don’t see anyone judging here.
 
That's not structural. Should be easy to repair. Worst case, might need some fabric work, but that's not hard either.

Do you know what the covering system is? That's worth looking into. My guess would be some variant of Dacron and dope.
 
Ed Haywood said:
That's not structural. Should be easy to repair. Worst case, might need some fabric work, but that's not hard either.

Do you know what the covering system is? That's worth looking into. My guess would be some variant of Dacron and dope.
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Thanks Ed,

It was recovered in 2017, I believe he said ceconite. Cosmetic is what I was hoping for. I’ll be looking at it hopefully soon and then schedule a prebuy. I appreciate everyone’s input.
 
Wingz4life said:
Thanks, I agree! Just a little tough on the useful load. Need around 450#. I found 3 so far that have it and am leaning on a Bc12d, chief, champ……
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if it is much of anything besides a stock Champ with a 1320gross weight or higher. Best to actually not validate the weight and balance to get that kind of useful load. Or don't plan on ever actually weighing it.
Have had a couple pilot ask me to train them in Champs but they could NOT find an examiner light enough to give them a check ride.
Most had electrical system and other add-ons or just several coats paint.
if it is less than the 1320, I think there is a pretty easy STC upgrade from 1220 to 1320 Gross weight. Had one pilot do that and was able to get his check ride in it.

Brian
 
Those rear windows are made up of 5 different pieces, some plywood and some solid spruce. The pieces are usually glued or screwed together. Over the years as the plane sits outside, water can rot the rear of the window at the arm rest end and the curved plywood piece. The fabric and headliner is glued and or stapled around the perimeter of the window frame. The plexiglass sits on top of that and an aluminum strip is over that. There's also a 1/4" x 3/4" spruce stringer that comes off the rear of the frame and straight down the side towards the tail too.
I would carefully sand and re-finish the wood you can get at just to extend its life and make it look better. Anything more than that would probably be removing some amount of fabric or the headliner then patching and refinishing that, or a full recover.
Remove the two shaped aluminum window piece covers and reseal it between the window plexiglass and wood frame to keep water out.
Do not waste your time calling Magellan, they don't make these planes and never did, they make parts in the aerospace industry, big difference. If anything, call American Champion in WI, they currently make these planes.
I have a 7AC currently under restoration and I have actually made these parts for my plane. I've owned my Champ since 1985 and I'm pretty familiar with the 7AC.
If you're near St Paul MN and would like to see my project, let me know.
 

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brcase said:
if it is much of anything besides a stock Champ with a 1320gross weight or higher. Best to actually not validate the weight and balance to get that kind of useful load. Or don't plan on ever actually weighing it.
Have had a couple pilot ask me to train them in Champs but they could NOT find an examiner light enough to give them a check ride.
Most had electrical system and other add-ons or just several coats paint.
if it is less than the 1320, I think there is a pretty easy STC upgrade from 1220 to 1320 Gross weight. Had one pilot do that and was able to get his check ride in it.

Brian
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Thanks Brian, I heard the same from a few people around the airport. Don’t get them near a scale, they have all gained weight even with no added accessories.
 
champ driver said:
Those rear windows are made up of 5 different pieces, some plywood and some solid spruce. The pieces are usually glued or screwed together. Over the years as the plane sits outside, water can rot the rear of the window at the arm rest end and the curved plywood piece. The fabric and headliner is glued and or stapled around the perimeter of the window frame. The plexiglass sits on top of that and an aluminum strip is over that. There's also a 1/4" x 3/4" spruce stringer that comes off the rear of the frame and straight down the side towards the tail too.
I would carefully sand and re-finish the wood you can get at just to extend its life and make it look better. Anything more than that would probably be removing some amount of fabric or the headliner then patching and refinishing that, or a full recover.
Remove the two shaped aluminum window piece covers and reseal it between the window plexiglass and wood frame to keep water out.
Do not waste your time calling Magellan, they don't make these planes and never did, they make parts in the aerospace industry, big difference. If anything, call American Champion in WI, they currently make these planes.
I have a 7AC currently under restoration and I have actually made these parts for my plane. I've owned my Champ since 1985 and I'm pretty familiar with the 7AC.
If you're near St Paul MN and would like to see my project, let me know.
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Thanks Champ! That was extremely detailed! If I end up buying it, I would patch it and seal it like you described. Not looking for a show plane, just something reliable to hit a bunch of grass strips and have coffee with the locals:)
 
pfarber said:
You're gonna need to research this a bit as repairs to longerons is a major repair. If you replace it with a factory/PMA part then its not a repair. If its a a former then its just a repair.
Click to expand...
They aren't longerons.
pfarber said:
Aeronca is owned by Magellen Aerospace. Maybe they have a support number for parts/tech ops.
Click to expand...
No it is not. American Champion owns the Type Certificates for all of them, and they build a few of them.
Doc Holliday said:
The major concern I would have with a 7AC is the AD on the spars. It takes a bit of effort to perform this AD and if the previous annuals were of the $200 variety, you may want to do a extensive prebuy to make sure you don't have a serious problem lurking there.
Click to expand...
That there. But the wing struts on those old Champs are made of a thinwalled steel streamline tubing, and I mean THIN-walled. They aren't sealed and moisture gets in there and rusts them out from the inside. By the time you see a blister they're badly compromised. One has to poke at them with an awl to find the rotten spots.

A busted wing strut is as bad as a busted spar.

Remember: There is no such thing as a cheap old airplane. Stop looking for one.
 
Dan’s advice also is true for the lower longerons.

The fabric wrapping around and holds moisture & they rot out.

Do the “Awl Thing “ to avoid welding and fabric work.
 
seems like you have your answer, and I certainly have nothing to add

Except that my 7 hours in a 7AC champ was hands down the most fun I've had flying. Also, the most frustrating, but that's another story... I'd love to get one and finally get a tailwheel sign-off, but I have no realistic hope of ever getting a hangar around here and wouldn't want to park one of those outside, especially with its wooden spar.

Hope you buy works out and taht you enjoy it!
 
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