TM 1-1520-265-23
Change 3
2-33
NOTE
Either probe identified in paragraph 2.15.3.1 may be used depending primarily on the
ease of accessibility and user friendliness. If the probes are changed, steps 2.15.3.5
b. (1), (2), and (3) shall be repeated each time a change is made.
2.15.3.7 Marking and Recording of Inspection Results. Mark and record inspection results as
required by paragraph 1.3.
2.15.4 Backup Method. Fluorescent Penetrant, refer to paragraph 1.4.7.
2.15.5 System Securing. The swashplate, if removed, requires installation in accordance with the
applicable technical manuals listed in Table 1-1.
2.16 LOWER LINK (ET).
2.16.1 Description (Figure 2-1, Index No. 16). The lower link provides the attaching point for the
rotating scissors and rotating swashplate.
2.16.2 Defects. Defects may occur anywhere on the surface of the lower link. No cracks are
allowed.
2.16.3 Primary Method. Eddy Current.
2.16.3.1 NDI Equipment and Materials. (Refer to Appendix B.)
a. Eddy Current Inspection Unit
b. Probe, straight, shielded surface, 2 MHz
c. Probe, right angle, shielded surface, 2 MHz, 90_ 1/2 inch drop
d. Cable Assembly
e. Adapter, probe, 2 MHz
f. Reference Block, three-notched titanium (0.008, 0.020, 0.040 EDM notches)
g. Teflon Tape, refer to Table 1-8
h. Aircraft Marking Pencil, refer to Table 1-8
2.16.3.2 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 lower
link shall be removed in accordance with the applicable technical manuals listed in Table 1-1.
2.16.3.3 Access. Access to the lower link is from the L/R engine cowl (Figure 1-4, Items 3T-7 and
4T-8).
2.16.3.4 Preparation of Part. The part shall be thoroughly cleaned. Refer to preparation of Part or
Area for NDI, paragraph 1.4.4.
