09/11/2018
RANS S-21 OUTBOUND
TEXT MANUAL
61
WING RIB / SPAR ASSEMBLY
1.
Lay the Forward Wing Spar Assembly on a table with the flange up. Locate the
wing truss, Lexan wing truss shim, and applicable hardware.
2.
Run a 1/4" and a 5/16" drill through the holes in the wing truss where the truss
bolts to the front and rear spars to remove the powder coat and allow the bolts to
slide freely.
3.
Bolt the strut truss fittings to the wing truss. Refer to Lift Strut Assembly PARTS
MANUAL DRAWING for parts listing. Note the orientation of the bolts are heads
down and nuts up. This is for wing strut fairing clearance. The 4 holes are
undersized and must be drilled to
1/4”.
a. Stack the Strut Truss Fittings together and bolt together with three 3/16
”
bolts. Use a drill press and drill one of the 3/16
” holes, through each fitting,
to 1/4".
b. While the fittings are stacked together, drill the 5/16
” hole to 7/16”. Un-bolt
fittings.
c. Place one fitting in position on the truss with a bolt through the 1/4" hole
and the 7/16
” that mates with the strut pointing away from the truss.
d. Carefully line up and drill the opposite hole through the fitting and the
truss. Put another bolt in the freshly drilled hole.
e. Drill out the remaining 2 holes.
f. The fitting that was just drilled is now matched to this particular side of this
truss. Mark the fitting and truss so that you know which truss and which
side of the truss it goes on.
g. Repeat with the other 3 fittings in the 3 remaining positions on the trusses
and mark accordingly.
h. Finish bolting the plates to the truss using the appropriate hardware. Do
NOT
fully tighten the bolts until after installing the wing on the fuselage
and the strut is bolted in place.
4.
Debur and soften the edges on the Forward Spar cutouts next to the wing truss
to prevent injury when the bolts are inserted to attach the wing truss.
5.
Bolt the truss to the Forward Spar using the appropriate hardware and the lexan
truss shim between the truss and the Forward Spar.
NOTE:
The nuts and bolts that need to be inserted from the inside of the
Forward Spar may be done by reaching into the cutouts in the spar on
either side of the truss.
6.
Lay the ribs on a flat table with the flanges up and use fluting pliers to straighten
the ribs so they lay flat on the table. Bend the flanges on the front and back of the
ribs to 90° if needed.