FAA Advisory Circular 43.13-1B
Acceptable Methods, Techniques, and Practices
Aircraft Inspection and Repair
AC 43.13-1B | 3. Fiberglass and Plastics | 3. Transparent Plastics | 3-26. Replacement Panels
9/8/98
AC 43.13-1B
repaired and similarly bevel its edges. Install
patches in accordance with figure 3-23. Heat
the plug until soft and press it into the hole
without cement and allow to cool to make a
perfect fit. Remove the plug, coat the edges
with adhesive, and then reinsert in the hole.
Maintain a firm light pressure until the cement
has set. Sand or file the edges level with the
surface, then buff and polish.
a. Clean the plastic by washing it with
plenty of water and mild soap, using a clean,
soft, grit-free cloth, sponge, or bare hands. Do
not use gasoline, alcohol, benzene, acetone,
carbon tetrachloride, fire extinguisher or deic
ing fluids, lacquer thinners, or window clean
ing sprays. These will soften the plastic and
cause crazing.
b. Plastics should not be rubbed with a
dry cloth since this is likely to cause scratches,
and also to build up an electrostatic charge that
attracts dust particles to the surface. If after
removing dirt and grease, no great amount of
scratching is visible, finish the plastic with a
good grade of commercial wax. Apply the
wax in a thin even coat and bring to a high
polish by rubbing lightly with a soft cloth.
FIGURE 3-23. Plug patch repair.
3-25. CLEANING AND POLISHING
TRANSPARENT PLASTIC. Plastics have
many advantages over glass for aircraft use,
but they lack the surface hardness of glass and
care must be exercised while servicing the air
craft to avoid scratching or otherwise damag
ing the surface.
c. Do not attempt hand polishing or
buffing until the surface is clean. A soft,
open-type cotton or flannel buffing wheel is
suggested. Minor scratches may be removed
by vigorously rubbing the affected area by
hand, using a soft clean cloth dampened with a
mixture of turpentine and chalk, or by applying
automobile cleanser with a damp cloth. Re
move the cleaner and polish with a soft, dry
cloth. Acrylic and cellulose acetate plastics
are thermoplastic. Friction created by buffing
or polishing too long in one spot can generate
sufficient heat to soften the surface. This con
dition will produce visual distortion and
should be avoided.
3-26. REPLACEMENT PANELS. Use
material equivalent to that originally used by
the manufacturer of the aircraft for replace
ment panels. There are many types of trans
parent plastics on the market. Their properties
vary greatly, particularly in regard to expan
sion characteristics, brittleness under low
Par 3-24
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