inspection ports

[R.Dennis]

I'm recoverying champ wings and wondered where are the best positions to place inspection holes. Some positions are given such as the holes needed for the lift struts and the aileron bellcrank. And I do have the old fabric, so I know where the old holes were but some the old holes don't seem like they are in very good positions. Does anyone have any suggestions?

[MikeB]

There is a service letter, I believe it came from American Champion that shows the location of inspection holes. I have a copy of it someplace around (in my desk?? in my shop?? at the airport?? who knows??) If I can find it, I can fax a copy of it to you. Basically, if I remember correctly, they were almost in every rib bay. Almost to the point where the bottom of the wing looked like a piece of swiss cheese. My suggestions would be to install the inspection rings/doilies where the service letter indicates, but not cut out until necessary. You can pretty much tell by looking at the old fabric and the critical spots where the holes need to be. Unless you're going to put in a engine with more than 90 hp. I wouldn't put in the upper inspection holes above the strut doubler. No matter which method you use (Rainbow or Champion) either is a poor design and could cause water to leak on top of the spar, in my humble opinion.

[visitor]

If you are building wings for an aircraft with less than 90hp, you do not need to put all of the holes described by the recent AD. You are doing the one time required inspection while you are recovering the wings and will not need to do it again. Be sure to note that inspection and sign off in the log books for the AD. There are other inspection holes however and they allow access to everything in the wing that can be adjusted, tightened or come loose. It is entirely possible that the covers that you removed did not have them correctly located. Lots of times they were installed close to the correct spot and could have been done better. Now is the right time to correct that. By placing a light on the opposite side of the wing, you should be able to figure out about where to put the rings to allow access to everything that you may ever want to get to in the wing.

[jerrymjr]

""There is a service letter, I believe it came from American Champion that shows the location of inspection holes. I have a copy of it someplace around (in my desk?? in my shop?? at the airport?? who knows??) If I can find it, I can fax a copy of it to you. Basically, if I remember correctly, they were almost in every rib bay. Almost to the point where the bottom of the wing looked like a piece of swiss cheese. ""


DO NOT USE THAT COPY
PLEASE DESTROY IT

That was a priliminary item released to a few people to get comment on.....NOT A FINAL DRAFT....it was rejected.
(namely by the author *cough* long story)
Somehow its out there being circulated. No one has to cut those 500 holes in the wing. Get rid of them for your guy's sake, not ours.

If you cant get a cover drawing from www.aeronca.com, you can buy one from ACA for $50 (half sized 7 drawings)....or was it $60? Anyway, I am unsure of the number, but its technically what you should reference in the log book when you recover. i.e. "Wings recovered per 7-????"
Expect ones a each end of the compression tubes for tighening dragwires and two at the rear strut for torquing the attachment bolt. If you are under 90 HP this should be good enough (AD is a one time). If you are not, figure out the minimum you will need for inspection and do that before painting...the extra's are put in per service letter 406 / 417. There are 2 or 3 top cover choices if you are over 90HP; good to do one of those before paint too.

[MikeB]

Not to worry, I can't find my copy anyway Not sure where it came from, either from my AI or off an old Aeronca/Bellanca site when we were going through all the wood (sparring). I probably destroyed it long ago after my wings were inspected.

Part of the problem was that when the wings were still covered, it was almost impossible to inspect the entire length of the spar without a sufficient amount of holes.

Of course, if the spar is inspected before covering that point is taken care of.

[Don Eide]

I did mine like Jerry said. One under each end of the compression tube. I also have two at the wing attach fitting area. (thats 10) One under the aileron bellcrank. (11) A book I have also shows one on top of the wing over the aileron bellcrank. (12) I didn't put that one in. I will only put it in if I REALLY need it. Probably put a fabric patch on afterwards. I HATE holes in the top of the wing. One behind the rear spar where the rear strut attaches, which is right in line with the one in front of the rear spar under a compression tube. (13) (12 for me) I also put one where the rear strut goes thru the fabric, and cut a cover to just fit around the strut. (13 for me) I have wing tanks, so I also put one just outside the wing tank to inspect the vent line rubber hose connections. Total of 14. NONE ON TOP. I also have a 115hp Lycoming, so I have to have that STUPID spar inspection every year. My IA inspects my airplane with a bend-a-light and a borescope using the holes I have.