TM 55-1520-240-23-4
5-75
REPAIR ROTARY-WING BLADE TRIM TAB (Continued)
5-75
1.
Blend out nicks and scratches on trim tab (1) as
follows:
a.
Blend nicks on edge (2) of trim tab (1). Use
file parallel to edge. Radius at corners (2)
must be at least 1/2 inch.
b.
Blend nicks or scratches on surface of trim
tab (1). Blend to width 20 times depth of
damage. Use abrasive paper (E9). Maximum
depth of rework shall not exceed 0.005 inch.
2.
Repair bond voids as follows:
a.
Tap suspect void areas with edge of coin to
find inboard void line.
b.
Remove finish from surface of blade (3) 1-1/2
inches around void area (4). Use abrasive
paper (E6).
c.
Remove finish from trim tab (1) where it
overlaps blade surface 1-1/2 inches beyond
bond void (4). Use abrasive paper (E9).
d.
Mask around sanded area. Use tape (E388)
(5).
e.
Flush bond void (4) with acetone (E20) until
only clear acetone flows. Use a hypodermic
syringe (E380) or squeeze bottle (E366).
Wear gloves (E184.1).
f.
Wipe sanded area with cloth (E120) damp
with acetone (E20). Wear gloves (E184.1).
Wipe dry with a clean cloth before acetone
evaporates.
g.
Cut a doubler (6) of fiberglass laminate (E168
or E168.1) 2 inches by 3 inches. Radius
corners 1/4 inch. Remove protective film
from both sides of doubler. Lightly sand both
sides of doubler to remove glaze.
h.
Cut a piece of scrim cloth (E325) (7) 1-3/4
inches by 2-3/4 inches.
i.
Center doubler (6) over trim tab (1) at bonded
void (4). Mark outline on blade surface. Use
a pencil.
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Change 2
