by sonex1678 » Fri Jan 22, 2016 2:52 pm
From what I see in the photos, there are two problems (I am building a Sonex, but I believe this applies to the Xenos also). First, as previously pointed out, the aileron drive plate/rib location is incorrect(this will affect the aileron width, but not the trailing edge alignment when installed); and, second, the location of the flap and aileron hinges on the wing trailing edge (rear spar) may be slightly off. Because the flap and aileron are attached to opposite edges ( top vs bottom) of the rear spar, their trailing edges will only line up at one position as the two surfaces pivot from different locations. As such, if the hinges are even very slightly misaligned, the trailing edges will not align well when both surfaces are at neutral (I know this from recent experience). If the aileron's trailing edge is "shorter", then the aileron's hinge half on the upper edge of the rear spar is further forward than the flaps' hinge half on the lower edge of the rear spar--if the opposite is the case, then the hinge relative positions are also the opposite. To fix, one of the hinge halves on the rear spar has to be removed and repositioned (remove, make new hinge half, drill and install so hinge half is in the correct location). Easiest way is to remove hinge half and use it as a template for hole position in new hinge half so it aligned with existing spar and skin holes, moving the holes as appropriate to position the hinge correctly. This is actually very easy and relatively quick. The key is to ensure that the hinges are installed such that the flap and aileron trailing edges align when the two surfaces are at neutral.
As previously stated, most Sonex's are a you describe, and it is only cosmetic, especially if both wings are the same, as is often the case (I think the source of the error is that the relative plane of the wing is different depending on which side is up, so the hinges are really not "centered" on the wing spar trailing edge, despite appearing to be so, when initially drilled). On the other hand, since it was an easy fix and I caught mine before riveting the hinges on to the spar, I fixed mine. Everything aligns now, but only at neutral--as both surfaces are lowered, the aileron trailing edge again gets "shorter" appearing because its pivot point is higher....
Sorry for the long explanation--hopes this might help...
v/r
Doug
Douglas B Scripture
Sonex 1678