(1) Outer Box Construction.
7-12. LIGHTNING STRIKE REPAIR. Since compos-
ite parts are nonconductive, a ine wire mesh is used
(a) Locate and drill 1/4 inch air holes on
to provide an electrical path through exterior com-
ponents in case the aircraft is struck by lightning.
Exterior composite parts without lightning mesh can
(b) Cover with two layers of breather cloth.
fail catastrophically due to lightning if this mesh is
not in place. Lightning mesh also provides an elec-
(c) Cover with vacuum bagging ilm; be
trical ground plane for electronic equipment such as
sure to use plenty of ilm and pleat it as
avionics or antennas. The mesh is typically on the
OML of the part, however IML application may be
necessary depending on the part design. Copper foil
(2) Process. The process is the same as with
is typically used for carbon laminates and aluminum
the production DVD tool except you do not have
is used on iber-glass laminates. Since repairing the
valves to turn the vacuum source on and off. If
laminate requires extensive removal of lightning mesh,
your vacuum probes have airtight valves, you may
the mesh must also be repaired. In certain cases
disconnect the vacuum hose; if not, you may need
the lightning mesh may be included as the outer-
to clamp the vacuum hose shut.
most ply in the repair and cocured with the repair.