Establish internal reference points.
Scan the inspection area thoroughly
Note any inconsistencies.
Evaluate the inconsistencies.
Report your conclusions.
GEOMETRIC ORIENTATION OF THE
and in an
To communicate information about an engine
inspection, you must establish a geometric frame of
reference for the engine assembly. A language for
describing the physical damage is also necessary. An
example of this information is provided in
geometric orientation of the LM2500 GTE.
shows an example of radial and axial cracking on a
compressor blade; figure 2-3 shows an example of
circumferential and axial cracking in the combustion
section. Table 2-1, a foldout at the end of this chapter,
provides a list of condition codes and definitions of
terms that you need to know when inspecting the
When the probe is in the inspection hole, it is not
unusual for you to lose your sense of direction. On
the Wolf borescope, the large plastic disk just beneath
the eyepiece has an index mark that shows the
direction the probe object window is facing. You can
feel and see this mark. Another reference you can use
to detect the direction the object window is facing is
Figure 2-3.Examp1es of circumferential and axial cracking.