What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

Wing LE rib to main spar hole mismatch?

sbalmos

Well Known Member
Just for fun, and to take a cool under construction pic for the coworkers to gawk over, I test-fit all of the main and leading edge ribs to my left wing spars tonight. Everything looks good, except the two most inboard W-909-L leading edge ribs. It looks as if the upper- and lower-most holes on the main spar have been pre-drilled too closely to their neighbor holes, and thus do not match with the rib holes. See pics below. The rib holes are evenly spaced, but the two upper and lower most spar holes are too close together. You can just barely see it, but the upper-most spar hole looks through onto the red ID stripe the factory puts on the rib.

My instinct is to match-drill new holes into the rib to match the spar's holes. My best guess, since the upper hole looks onto the red stripe, is that the new holes would be centered between the two existing holes. But has anyone else experienced this? Does this seem okay to just drill new holes in the rib's flange?

IMG_20121016_225536.jpg


IMG_20121016_225559.jpg
 
LE Rib to Main Spar Hole Mismatch

I'm building a RV-7, but I did run into the same issue. The spar is used as a point of reference for placing the missing holes in the rib flange. Here's an excerpt from the RV-7 manual regarding the leading edge ribs. I hope this helps.

LERibHoles.jpg
 
Huh

Scott,

I don't remember having that issue, but I'll check my build later this afternoon. This is an outboard leading edge rib you're talking about?

Tom
 
Tom,

No, these are the two inboard-most W-909 leading edge ribs, more or less near the center of the wing. When counting from outboard to inboard, they're the first two inboard ribs that are riveted also to the doubler on the main spar.

It looks like cka357 hit it with his 7's plans. I just wanted a double-check from a 9's perspective. Might just send these pics to Van's if I can't get something definitive here.
 
grayforge, I wouldn't be asking the question if it did. :)

Bruce: THANKS! I searched around here for any other threads mentioning this. Guess I just didn't use the right search incantations.
 
Nose rib

Scott,

Here is a pic of the back of my spar where that nose rib is attached.
As you can see there are 6 rivets and the spacing of the outer 2 hole is less than the other holes. I don't remember having to drill those holes in the nose rib flange, but I very well may have. Does this help?
(The blue marks on the rivet heads are residual masking tape that I cover the heads with before I rivet.)

3609C3B7-7BBF-4D19-B311-64DFD96845C2-15231-000010BDC267123D.jpg
 
I looked at my work instructions for my 9A, I didn't see any similar verbiage. Here is a shot of that particular rib as I was fitting them up. The holes are in the spar for the additional rivets into the 909 leading edge rib, I just drilled and riveted them.

1001221j.jpg
 
Last edited:
Wing LE rib to Main Spar Hole Mismatch

Gang,

I failed to attach a screen capture of the -7 drawing for reference with the verbage from the manual earlier. My apologies. This picture should help.

Chuck

LERibHoles2.jpg
 
Back
Top