We started working on an outboard flaperon yesterday. The outer flaperon (aileron?) rear rib top and bottom holes line up with the spar flange, but the “inner” ribs do not since they’re displaced a bit by the thickness of the o/b top and bottom spar doublers.

The drawings say there will eventually be an A4 rivet there that goes through 4 or 5 layers, for the top and bottom respectively. No matter if I use an A4 or upsize it to an A5, the hole in the rib flange will be oblong. 

the attached pic shows how off the holes are between the rib and the spar. The rib in the photo is flush/clecoed to the spar web. We haven’t tried to put on the skins yet, but I bet those holes will be misaligned as well. 

Did we do something wrong? I haven’t checked, but I assumed that aside from being specific to L vs R, every rib was identical in terms of the pre-drilled holes. 


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There are my suggestions and solution :

1- replace the aileron stiffener rib by another one or

2- make a doubler inside the stiffener rib (in a L Form) and drill it to aligned it with your top channel without alignement with your wrong positioning hole in you rib stiffener. Yes the existing hole in the rib will be elongated, but will not support anymore the rib stiffener. Insure have 3 ou 4 rivet attach your added L support tiffener to you existing Rib Stiffener.

This is how I think you can solve easely this mismatch.


CH640-0059 from plan

Not sure if the reinforcing L angle, which I think is what Christian is referring to is causing your problem, but it did in mine and I made new parts myself, it was relatively easy: http://www.mykitlog.com/users/display_log.php?user=n2charlie&pr...


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