TM 1-1520-264-23
3.3.3.6
Inspection Procedure. Refer to Eddy Current Method, paragraph 1.4.11 and Figure 3-3.
a.
Place probe on a good area in the inspection location and null. Adjust phase as required to obtain horizontal
lift-off.
b.
Inspect the part.
c.
Any signal similar to the notches in the test block is cause for rejection.
NOTE
Either probe identified in paragraph 3.3.3.1 may be used depending primarily on
the ease of accessibility and user friendliness. If the probes are changed, steps
3.3.3.5 b. (1), (2), and (3) shall be repeated each time a change is made.
3.3.3.7
Marking and Recording of Inspection Results. Mark and record the inspection results as required by
paragraph 1.3.
3.3.4
Backup Method. None required.
3.3.5
System Securing. The drivetrain couplings, if removed, require installation in accordance with the applicable
technical manuals listed in Table 1-1.
3.4
DRIVETRAIN FLANGES (MT).
3.4.1
Description (Figure 3-1. Index No. 4). The drivetrain flanges are used throughout the drive system to mate
the drive shaft assemblies to the main transmission and various gear boxes contained in the drive system.
3.4.2
Defects. This inspection is used to verify crack indications found visually on the drivetrain flanges. No cracks
are allowed.
3.4.3
Primary Method. Magnetic Particle.
3.4.3.1
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
3.4.3.2
Preparation of Helicopter. The helicopter shall be prepared for safe ground maintenance and the drive shaft
removed in accordance with the applicable technical manuals listed in Table 1-1.
3-8
