FAA Advisory Circular 43.13-1B
Acceptable Methods, Techniques, and Practices
Aircraft Inspection and Repair
AC 43.13-1B | 5. Nondestructive Inspection (NDI) | 2. Visual Inspection | 5-15. General
9/8/98
SECTION 2. VISUAL INSPECTION
AC 43.13-1B
5-15. GENERAL. Visual inspection is the
oldest and most common form of NDI for air-
craft. Approximately 80 percent of all NDI
procedures are accomplished by the direct vis-
ual methods. This inspection procedure may
be greatly enhanced by the use of appropriate
combinations of magnifying instruments,
borescopes, light sources, video scanners, and
other devices discussed in this AC. Visual in-
spection provides a means of detecting and ex-
amining a wide variety of component and ma-
terial surface discontinuities, such as cracks,
corrosion, contamination, surface finish, weld
joints, solder connections, and adhesive dis-
bonds. Visual inspection is widely used for
detecting and examining aircraft surface
cracks, which are particularly important be-
cause of their relationship to structural failures.
Visual inspection is frequently used to provide
verification when defects are found initially
using other NDI techniques. The use of opti-
cal aids for visual inspection is beneficial and
recommended. Optical aids magnify defects
that cannot be seen by the unaided eye and also
permit visual inspection in inaccessible areas.
5-16. SIMPLE VISUAL INSPECTION
AIDS. It should be emphasized that the eye-
mirror-flashlight is a critical visual inspection
process. Aircraft structure and components
that must be routinely inspected are frequently
located beneath skin, cables, tubing, control
rods, pumps, actuators, etc. Visual inspection
aids such as a powerful flashlight, a mirror
with a ball joint, and a 2 to 10 power magni-
fying glass are essential in the inspection proc-
ess.
a. Flashlights. Flashlights used for air-
craft inspection should be suitable for indus-
trial use and, where applicable, safety ap-
proved by the Underwriters Laboratory or
equivalent agency as suitable for use in haz-
ardous atmospheres such as aircraft fuel tanks.
Military Specification MIL-F-3747E, flash-
lights: plastic case, tubular (regular, explosion-
proof, explosion-proof heat resistant, traffic di-
recting, and inspection-light), provides re-
quirements for flashlights suitable for use in
aircraft inspection. However, at the present
time, the flashlights covered by this specifica-
tion use standard incandescent lamps and there
are no standardized performance tests for
flashlights with the brighter bulbs: Krypton,
Halogen, and Xenon. Each flashlight manu-
facturer currently develops its tests and pro-
vides information on its products in its adver-
tising literature. Therefore, when selecting a
flashlight for use in visual inspection, it is
sometimes difficult to directly compare prod-
ucts. The following characteristics should be
considered when selecting a flashlight: foot-
candle rating; explosive atmosphere rating;
beam spread (adjustable, spot, or flood); effi-
ciency (battery usage rate); brightness after
extended use; and rechargeable or standard
batteries. (If rechargeable, how many hours of
continuous use and how long is required for
recharging?) If possible, it would be best to
take it apart and inspect for quality of con-
struction and to actually use the flashlight like
it would be used in the field. Inspection flash-
lights are available in several different bulb
brightness levels:
(1) Standard incandescent (for long-
battery life).
(2) Krypton (for 70 percent more light
than standard bulbs).
(3) Halogen (for up to 100 percent more
light than standard bulbs).
(4) Xenon (for over 100 percent more
light than standard bulbs).
Par 5-15
Page 5-9