FAA Advisory Circular 43.13-1B
Acceptable Methods, Techniques, and Practices
Aircraft Inspection and Repair
AC 43.13-1B | 11. Aircraft Electrical Systems | 16. Wire Marking | 11-214. Identification Sleeves
9/27/01
AC 43.13-1B CHG 1
contour of the wire, are heated to the desired
temperature. Wire is pulled through a channel
directly underneath the characters. The heat of
the type set characters transfers the ink from
the marking foil onto the wire.
a. Good marking is obtained only by the
proper combination of temperature, pressure,
and dwelling. Hot stamp will mark wire with
an outside diameter of 0.038 to 0.25-inch.
b. Before producing hot stamp wire, it
must be assured that the marking machine is
properly adjusted to provide the best wire
marking with the least wire insulation deterio
ration. The marking should never create an
indent greater than 10 percent of the insulation
wall.
CAUTION: The traditional Hot
Stamp method is not recommended
for use on wire with outside diameters
of less than 0.035. (REF. SAE
ARP5369). Stamping dies may cause
fracture of the insulation wall and
penetration to the conductor of these
materials. When various fluids wet
these opening in service, arcing and
surface tracking damage wire bun-
dles. Later in service, when various
fluids have wet these openings, serious
arcing and surface tracking will have
damaged wire bundles.
11-211. DOT MATRIX MARKING. The
dot matrix marking is imprinted onto the wire
or cable very similar to that of a dot matrix
computer printer. The wire must go through a
cleaning process to make sure it is clean and
dry for the ink to adhere. Wires marked with
dot matrix equipment require a cure consisting
of an UV curing process, which is normally
applied by the marking equipment. This cure
should normally be complete 16 to 24 hours
after marking. Dot matrix makes a legible
mark without damaging the insulation. De
pending on equipment configuration, dot ma
trix can mark wire from 0.037 to 0.5-inch out
side diameter. Multi-conductor cable can also
be marked.
11-212. INK JET MARKING. This is a
“non-impact” marking method wherein ink
droplets are electrically charged and then di
rected onto the moving wire to form the char
acters. Two basic ink types are available:
thermal cure and UV cure.
a. Thermal cure inks must generally be
heated in an oven for a length of time after
marking to obtain their durability. UV cure
inks are cured in line much like dot matrix.
b. Ink jet marks the wire on the fly and
makes a reasonably durable and legible mark
without damaging the insulation. Ink jets
normally mark wire from 0.030 to 0.25-inch
outside diameter. Multiconductor cable can
also be marked.
11-213. LASER MARKING. Of the variety
of laser marking machines, UV lasers are
proving to be the best. This method marks
into the surface of the wire’s insulation without
degradation to its performance. One common
type of UV laser is referred to as an excimer
laser marker. UV laser produces the most du
rable marks because it marks into the insula
tion instead of on the surface. However, exci
mer laser will only mark insulation that con
tain appropriate percentages of titanium diox
ide (TiO2). The wire can be marked on the fly.
UV can mark from 0.030 to 0.25-inch outside
diameter. The UV laser makes only gray
marks and they appear more legible on white
or pastel-colored insulation.
11-214. IDENTIFICATION SLEEVES.
Flexible sleeving, either clear or opaque, is
satisfactory for general use. When color-coded
or striped component wire is used as part of a
cable, the identification sleeve should
Par 11-221
Pages 11-85