TM 1-1520-253-23
NOTE
This setup is very sensitive to thin skin-to-core bonding. Move probe slowly over the
skin and note the slight amplitude change (bounce) as the probe senses alternately the
honeycomb cell nodes and cell walls. Be sure of panel configuration. Panel edges and
attachment points may not be bonded structure and do not normally contain
honeycomb. These areas will respond similarly to voids with the Bondmaster. Panels
having rigidized skins are more easily scanned using wide Teflon tape on the probe
holder.
4.13.3.7
Marking and Recording of Inspection Results. Mark and record as required by paragraph
NOTE
Attention shall be directed to accurately mark the boundaries of all voids. These
markings will be needed to determine acceptance or rejection criteria in accordance
with applicable technical manuals,
4.13.4 Backup Method. None required.
4.13.5 System Securing. If removed, install the work platforms in accordance with the applicable technical manuals
listed in Table 1-1.
FORWARD LANDING GEAR SUPPORT STRUCTURE (ET).
4.14.1 Description (Figure 4-1. index No. 14). This inspection is applicable to both of the forward landing gear support
structures.
4.14.2 Defects. Defects may occur anywhere on the surface of the forward landing gear support structure. No cracks
are allowed.
4;14.3 Primary Method. Eddy Current.
a.
Eddy Current Inspection Unit
b.
Probe, straight, shielded surface, 100 KHz-500 KHz
c.
Probe, right angle, shielded surface, 100 KHz-500 KHz, 901/2 inch drop
d.
Cable Assembly
e.
Reference Block, three-notched aluminum (0.008, 0.020, and 0.040 EDM notches)
f.
Teflon Tape, refer to Table 1-8
g.
Aircraft Marking Pencil, refer to Table 1-8
