TM 1-1520-264-23
a.
Select AC on the AC/DC power switch.
b.
Place probe/yoke on part in position 1 as shown.
c.
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.
d.
Inspect for cracks using the black light.
e.
Demagnetize before moving to the next position. Refer to paragraph 3.25.3.8.
f.
Repeat steps a. through e. for position 3-25..
3.25.3.7
Marking and Recording of Inspection Results. Mark and record the inspection results as required by
paragraph 1.3.
3.25.3.8
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.
3.25.4
Backup Method. None required.
3.25.5
System Securing. Clean the tail rotor gearbox forward and aft strut 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 tail rotor
gearbox forward and aft strut, if removed, require installation in accordance with the applicable technical manuals listed
in Table 1-1.
3.26
TAIL ROTOR GEARBOX FORWARD AND AFT STRUT FITTINGS (MT).
3.26.1
Description (Figure 3-1. Index No. 26).
The tail rotor gearbox forward and aft strut fittings provide for attachment
of the forward and aft struts to the vertical stabilizer.
3.26.2
Defects. This inspection is used to verify crack indications found visually on the tail rotor gearbox forward and
aft strut fittings. No cracks are allowed.
3.26.3
Primary Method. Magnetic Particle.
3.26.3.1
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.
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