NDI Equipment and Materials. (Refer to Appendix B.)
Eddy Current Inspection Unit
Probe, straight, shielded surface, 100 KHz-500 KHz
Probe, right angle, shielded surface, 100 KHz-500 KHz, 90
1/2 inch drop
Reference Block, three-notched aluminum (0.008, 0.020, and 0.040 EDM notches)
Teflon Tape, refer to Table 1-8
Aircraft Marking Pencil, refer to Table 1-8
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 starter flange shall be removed in accordance with the applicable
technical manuals listed in Table 1-1.
Access. Access is through engine access doors (Figure 1-4, Items LN1 or RN1).
Preparation of Part. The part shall be thoroughly cleaned. Refer to Preparation of Part or Area for NDI,
NDI Equipment Settings.
Make the following initial settings on the Eddy Current Inspection Unit, NORTEC-19ell.
- 200 KHz
Refer to Eddy Current Method, paragraph 1.4.11. Set up on test block as follows:
Null probe on test block.
Adjust phase as required to obtain horizontal lift-off.
Move probe over all three notches in test block. Adjust gain to obtain a three block vertical signal when
probe is passed over 0.040-inch notch in test block. (See the standard instrument display shown in Figure
Inspection Procedure. Refer to Eddy Current Method, paragraph 1.4.11 and Figure 5-8.
Place probe on a good area in the inspection location and null. Adjust phase as required to obtain horizontal
Inspect the part.
Any signal similar to the notches in the test block is cause for rejection.