THRUSH S2R – G10 Maintenance Manual page 143

AIRCRAFT MAINTENANCE MANUAL
and position the wings so that black
lines drawn in step "D" are visible
and that they appear symmetrical
between left and right wings. This
centers the wings with respect to the
fuselage. Repeat step "E" if the 3/16
inch clearance has changed.
G. Transfer the location of each of the
holes through the bushings in the
vertical fuselage member to the
attach angle by sliding a 5/16 inch
drill bit (preferably one that has a
pilot tip), through each of the four
holes in succession. Twist the drill
just enough to make a mark on the
angle. Do not drill these holes yet
because edge distance must be
checked.
H. Remove the angle and check to
confirm that the mark for the bottom
hole is at least 5/8 (2X hole
diameter) inch away from the lower
edge of the angle. If it is not, file the
bottom edge of the other leg of the
angle (which comes into contact with
the lower spar cap) in such a manner
as to allow the angle to be lowered
and yet provide clearance from the
lower spar cap.
transfer procedure and recheck for
edge distance if adjustments had to
be made..
I. When the wings are properly located
and edge distance is adequate, mark
the four fuselage bushing locations
on the outboard angles by using a
transfer punch through the bushings.
J. Remove the outboard attach angles
and drill the 5/16" holes in the
punched locations.
K. Place the inboard attach angles back
to back against the outboard angles.
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Page
THRUSH AIRCRAFT, INC – MODEL S2R-G10
Repeat the hole
Align and clamp the two angles and
transfer drill the 5/16 inch holes through
the inboard angles using the holes in the
outboard attach angles as a drill guide..
L. Temporarily install the four wing attach
angles to the fuselage down tubes and
torque the 5/16 inch nuts and bolts to
specification.
M. Again sight through the ¼ inch bolt
holes through the main spar web and
confirm that the black lines appear
symmetrical between the left and right
wings.
N. Transfer the location of the ¼ inch holes
to the four wing attach angles, using the
main spar web as an index. A few holes
may be drilled and bolts installed to
keep the spar web flush with the forward
face of the angles for transfer accuracy.
Use caution not to enlarge the holes
through the spar web.
O. Mark and remove the four attach angles
and drill and ream the ¼ inch holes at
the marked locations with a drill press or
milling machine (.250"/.254"). Deburr all
holes.
P. Reattach the wing attach angles to the
wing spar and fuselage and torque all
nuts and bolts to the specification called
out in Table 7-3.
Q. Remove the ½ inch temporary spacers
between the lower longeron and the
lower spar cap.
R. Release the wing supports and check
the wing dihedral for 3 ½ degrees.
S. Complete the
making the necessary connections in
the electrical, fuel, pitot, and flight
control systems.
wing installation by
Effective: 03/26/2010