TM 1-1520-264-23
4.35.3.6 Inspection Procedure. Refer to Eddy Current Method, paragraph 1.4.11 and Figure 4-35.
a.
Place probe on a good area in the inspection location and null. Adjust phase as required to obtain horizontal
lift-off.
b.
Inspect the part.
c.
Any signal similar to the notches in the test block is cause for rejection.
NOTE
Either probe identified in paragraph 4.35.3.1 may be used depending primarily on the ease of accessibility
and user friendliness. If the probes are changed, steps 4.35.3.5 b. (1), (2), and (3) shall be repeated each
time a change is made.
4.35.3.7 Marking and Recording of Inspection Results. Mark and record the inspection results as required by paragraph
1.3.
4.35.4
Backup Method. None required.
4.35.5
System Securing. The tail landing gear trailing arms, if removed, require installation in accordance with the
applicable technical manuals listed in Table 1-1.
4.36
TAIL LANDING GEAR ACTUATING CYLINDER ASSEMBLY (ET).
4.36.1
Description (Figure 4-1. Index No. 36).
The tail landing gear actuating cylinder allows the tail wheel to lock.
4.36.2
Defects. Defects can occur anywhere on the surface of the tail landing gear actuating cylinder. No cracks are
allowed.
4.36.3
Primary Method. Eddy Current.
4.36.3.1 NDI Equipment and Materials. (Refer to Appendix B.)
a.
Eddy Current Inspection Unit
b.
Probe, straight, shielded surface, 100 KHz-500 KHz
c.
Probe, right angle, shielded surface, 100 KHz-500 KHz, 90
°
1/2 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
4.36.3.2 Preparation of Helicopter. The helicopter shall be prepared for safe ground maintenance. A partial inspection
for cause (visual indications, sites of mechanical damage, corrosion, etc.) may be performed on all exposed surfaces of
the installed part using this procedure. If required, the tail landing gear actuating cylinder shall be removed in
accordance with the applicable technical manuals listed in Table 1-1.
4-79
