NOTE: The above repair is permissible
when the damage does not exceed two-thirds
of the width of one leg of the stringer and is
not over 12 inches in length. When the
damage is of such length that a single
reinforcement splice would involve an
excessive amount of material and work, a
repair by insertion should be made. See
figure 13-68.
SPARS.—Spars (also called beams) are the main
spanwise members of the wing, stabilizers, and other
airfoils. They may run the entire length of the airfoil.
Spars are designed primarily to take bending loads
imposed on the wing or other airfoil.
The most common type of spar construction
consists of extruded capstrips, a sheet metal web or
plate, and a vertical angle stiffener. Since spars are
very highly stressed members, their repair may not be
permitted; and if permitted, must be made in strict
accordance with instructions given in the structural
repair manual, using the best possible workmanship.
Figure 13-69 shows a spar web repair by insertion.
Figure 13-68.—Stringer repair by insertion.
13-50
