super D wing root fairings have broke rivets

[chopperpilot1955]

I have a 1979 Super D and today after short flight I noticed that 5 rivets that secure metal wing roots to first rib have the popped off. After further inspection I found no other issues or problems. I'm curious if this is a common problem or do I need to get out my crying towel. Has anyone had this problem.

Gene M

 

[jerrymjr]

It fairly common. There is a compound curvature that puts pre-strain on the skin.

Metal Spar Wings after 1996, we bumped the Butt Rib to 0.040" and added a number of cherry rivets (to beef that up). Also did some trimming on the wood formers that it mates to, to reduce the pre-strain. All of this is not infallible and you still have spiraling slipstream and unconventional acrobatic loads beating on the area.

It sounds like the damage is minimal. You might just re-rivet it down with some cherry-max; offset an inch from the old hole. If you feel ambitious, get a doubler on the inside of the rib to rivet it too.