TM 1-1520-264-23
3.15.3.7 Marking and Recording of Inspection Results. Mark and record the inspection results as required by paragraph
1.3.
3.15.3.8 Demagnetization. With the switch remaining in the AC position, place the probe/yoke legs in the same position
used for magnetizing. Press the test switch and withdraw the probe/yoke from the part for a distance of two feet before
releasing the switch.
3.15.4
Backup Method. None required.
3.15.5
System Securing. Clean the main transmission APU drive flange thoroughly to remove all residual magnetic
particle media. Refer to Post Cleaning and Restoration of Part or Area After NDI, paragraph 1.4.16. The main
transmission APU drive flange requires installation in accordance with the applicable technical manuals listed in Table
1-1.
3.16
MAIN TRANSMISSION TAIL ROTOR DRIVE FLANGE (MT).
3.16.1
Description (Figure 3-1. Index No. 16). The main transmission tail rotor drive flange is externally splined
which provides for connection of the number 3 tail rotor drive shaft to the main transmission.
3.16.2
Defects. This inspection is used to verify crack indications found visually on the main transmission tail rotor
drive flange. No cracks are allowed.
3.16.3
Primary Method. Magnetic Particle.
3.16.3.1 NDI Equipment and Materials. (Refer to Appendix B.)
a.
Magnetic Particle Inspection Probe/Yoke
b.
Magnetometer
c.
Black Light
d.
Fluorescent Magnetic Particles, refer to Table 1-8
e.
Consumable Materials, refer to Table 1-8
f.
Aircraft Marking Pencil, refer to Table 1-8
NOTE
Hand-held magnetic coil may be used. Refer to paragraph 1.4.8.1.2 and Figure 1-6.
3.16.3.2 Preparation of Helicopter. The helicopter shall be prepared for safe ground maintenance and the main
transmission tail rotor drive flange removed in accordance with the applicable technical manuals listed in Table 1-1.
3.16.3.3 Access. Not applicable.
3.16.3.4 Preparation of Part. The part shall be thoroughly cleaned. Refer to Preparation of Part or Area for NDI,
paragraph 1.4.4.
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