Hand-held magnetic coil may be used. Refer to paragraph 184.108.40.206.2 and Figure 1-6.
220.127.116.11 Preparation of Helicopter. The helicopter shall be prepared for safe ground maintenance and the main
transmission APU drive flange removed in accordance with the applicable technical manuals listed in Table 1-1.
18.104.22.168 Access. Not applicable.
22.214.171.124 Preparation of Part. The part shall be thoroughly cleaned. Refer to Preparation of Part or Area for NDI,
126.96.36.199 NDI Equipment Settings. Refer to Magnetic Particle Method, paragraph 1.4.8.
188.8.131.52 Inspection Procedure. A magnetic field shall be applied to the part perpendicular to the
orientation of possible cracks. Positions required for this inspection are illustrated in Figure 3-15.
Select AC on the AC/DC power switch.
Place probe/yoke on part in position 1 as shown.
Press the test switch and apply a light coat of magnetic particle media at the same time.
Remove the media momentarily before removing the current. Current should be applied for
no more than five seconds.
Inspect for cracks using the black light.
Demagnetize before moving to the next position. Refer to paragraph 184.108.40.206.
Repeat steps a. through e. for position 2.
Figure 3-15. Main Transmission APU Drive Flange