TM 1-1520-253-23
4.18.3 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
4.18.3.2
Preparation of Helicopter. The helicopter shall be prepared for safe ground maintenance. 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 aft landing gear shall be removed in accordance with
the applicable technical manuals listed in Table 1-1.
4.18.3.3
Access. Not applicable.
4.18.3.4
Preparation of Part. The areas of interest shall be thoroughly cleaned. Refer to Preparation of Part or
Area for NDI, paragraph 1.4.4.
