The spar pillar spacing I accidently deleted some of the threads about this subject, and like Mark, I have no real engineering experiese in this area. I do remember that these pillars have been called load distribution blocks. In a discussion long ago it was mentioned that if the rigidity of the wing changed, then the stress is changed(moved). It was said that care must be taken to ensure that the stress load that would be taken up by the bending of the spar of a standard wing is not somehow transferred to the WAF's by a wing that no longer bends as it should as would be the case by changing the spacing of the load distribution blocks or in some other way making the spar less flexable like installing a large tank. My non expert opinion is that if the wing is less flexible then the original design then the G loading of the wing should be reduced.
Orma L. Robbins Southfield MI 19 Years flying KR-2 N110LR http://www.aviation-mechanics.com
