David,

The 5.1 inch measurement is to the edge of the foam. The wing leading edge is an additional .3 inches thick. So the current location is 5.4 inches from the leading edge.

That puts the CG roughly .1 inch ahead of the axles as stated (at the rearmost cg location of 5.31).

Mitch

oops, fired this before reading the note at the bottom of your post, never mind as well![8D]