Friday, October 31, 2014

Spar bend -- OK or not?

When I unpacked the wing kit many moons ago (way too many) I noticed that the inboard end of the right wing spar bent aft a degree or so at the point where the ribs end and the tapered part of the spar, the part which passes through the fuselage, begins.  Examination of the left spar showed a similar but lesser bend in the opposite direction.  I convinced myself that this had to be by design.  The spars have
individual serial numbers and, being one of the most critical components of the entire airplane, were surely subjected to tight quality control.  As I proceeded through construction of the wing kit, preparing and installing all the ribs, I periodically pondered the very noticeable bends and became increasingly troubled by them.  Before skinning the wings, I figured I'd better get a ruling from the Mother Ship.  In retrospect, of course, I should have done this much earlier, probably before attaching ribs.  I carefully quantified the bends with measurements and sent the results along with the above pic to support at Van's.  The quick reply from Ken Scott was "The ends of the spars always go slightly one way or another, and it doesn't matter at all.  
Once they're installed in the airplane and the pins are through the holes, all will be well."  Instant relief from my self-inflicted worry.