FAA Advisory Circular 43.13-1B
Acceptable Methods, Techniques, and Practices
Aircraft Inspection and Repair
AC 43.13-1B | 5. Nondestructive Inspection (NDI) | 12. Shearography | 5-134. General
9/8/98
SECTION 12. SHEAROGRAPHY
AC 43.13-1B
5-134. GENERAL. Shearography was de-
veloped for strain measurements. The process
now provides a full-field video strain gauge,
in real time, over large areas. It is an en-
hanced form of holography, which requires
the part to be under stress. A laser is used for
illumination of the part while under stress.
The output takes the form of an image proc-
essed video display. This technique has been
used effectively in locating defects, such as
disbonds and delaminations, through multiple
bondlines. It is capable of showing the size
and shape of subsurface anomalies when the
test part is properly stressed. Shearography
has been developed into a useful tool for NDI.
It can be used easily in a hangar environment,
while meeting all laser safety concerns. Other
applications include the testing of honeycomb
structures, such as flaps and control surfaces.
Shearography offers a great increase in the
speed of inspection by allowing on-aircraft in-
spections of structures without their removal,
as well as inspections of large areas in just
seconds.
5-135.5-140. [RESERVED.]
Par 5-134
Page 5-55 (and 5-56)