TB 1-1615-351-23
p. Check Track and Balance. Check track and balance of the tail rotors per the -23 aircraft Technical Manual.
q. Tail Rotor Blade Erosion/Spark Guard Coating (Repair).
(1) Peeling and Tattering. This condition is most prevalent where the material is thinnest. The blades should be
inspected after flight and the loose material, if any should simply be trimmed off with a sharp knife. It is not necessary to
re-coat the bare area until there is enough area to justify a coating cure cycle of six or more hours.
(2) Nicks and Cuts.
CAUTION
Be careful when using a knife for trimming. Do not cut into the blade. The safest
technique is to work the knife under the loose material and cut parallel to the blade
surface.
(a) This condition is caused by larger debris and will usually be found close to the leading edge and in the
outboard one-third of the rotor span. If the cut is of average size the surrounding material will not be damaged and no
debonding will occur. This type of damage to the coating should not be treated until it is expected that further flight would
cause that area to debond and tear away. If that is the case, then cut out the debonded area with a sharp knife. Only
remove the debonded area. Repair by applying fresh coating, in several applications if necessary, to restore the coating
to its original thickness. Allow the coating to set for at least six hours before bringing the rotor up to speed or flying the
aircraft.
(b) If mission req uirements will not permit the proper time for repair and curing, simply cut away the loosened
material and fly.
r. Tail Rotor - Erosion/Spark Guard Coating (Removal).
CAUTION
Do not cut the rotor blade structure. Use extra caution when removing the material
from rotor blades made from composite materials.
This coating is relatively immune to most solvents and to abrasive cleaning techniques. The recommended removal
procedure is by scraping in a direction along the surface of the blade.
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