[ScottSchmidt]

Tonight we started adding the front ribs to the left wing and found that rib#6 (from the outside) was too long. We attached the rib to the angle that is assembled at the factory and found there was a gap between the spar and the rib. This is page 15-05, Step #2.

This just did not seem right, so we measured the rib from the web of the spar to the end of the spar and sure enough, it was 3/16" too long, it just would not line up. This would cause many problems when the skins are added.

Every rib measured 22 3/16" from web.

RIB #6 - 22 3/8"

I did some searching and only found this post on 15-05 - Step #2
http://www.vansairforce.com/community/showthread.php?t=36544&highlight=15-05

It appears the angle is too long or the holes were placed too far from the spar in the angle. This can be easily fixed by first clecoing the rib to the spar and drilling new holes between the 6 pre-punched holes. You could drill 5 holes with good spacing.

Has anyone else seen this or had trouble making rib #6 line up with the skins or do we just have a bad angle bracket?

We will get the modification I proposed approved through Van's tomorrow and let you know.

 

[vernhendershott]

Yes the people who build up the spars for Van's put the wrong rib clip on from time to time, I had one that was to short. Your idea for a fix is good but you do need to get it approved by Van's in writing and have it for the DAR when you are ready to get your aircraft inspected and certified. They must ask you if you made any changes to the plans, with this change you can say yes and that you have Van's approval for the change to fix a Van's kit part defect. This shows the DAR that you have the correct disposition to comply and unless he finds some other big issue on the aircraft you will do the paper work and be done.

Best regards,
Vern

 

[joedallas]

Wing rib fix

Yes the people who build up the spars for Van's put the wrong rib clip on from time to time, I had one that was to short. Your idea for a fix is good but you do need to get it approved by Van's in writing and have it for the DAR when you are ready to get your aircraft inspected and certified. They must ask you if you made any changes to the plans, with this change you can say yes and that you have Van's approval for the change to fix a Van's kit part defect. This shows the DAR that you have the correct disposition to comply and unless he finds some other big issue on the aircraft you will do the paper work and be done.

Best regards,
Vern

I wonder if Vans could send you a new rib with no holes at the clip end.
Then you could Match-Drill the clip holes to the new Rib.

Joe Dallas
www.joesrv12.com

 

[ScottSchmidt]

Follow-up

Just to follow up. The angle was the wrong one. They installed one of the angles that is used on the "inside" of the spar.

Van's had no problem with our modification.

Just another item to watch for when checking the spar or double checking the rib length. There is no way you could skin this so I am pretty sure you will catch it. Hopefully we are the only ones with this issue but people may have something to search for in the RV-12 forum in the future.