TM 1-1520-253-23
b.
Refer to Eddy Current Method, paragraph 1.4.11. Set up on test block as follows:
(1)
Null probe on test block.
(2)
Adjust phase as required to obtain horizontal lift-off.
(3)
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. (Refer to standard instrument display shown
in Figure 1-7.)
3.16.3.6
Inspection Procedure. Refer to Eddy Current Method, paragraph 1.4.11 and Figure 3-16.
a.
Place probe on part 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 3.16.3.1 may be used depending primarily on
the ease of accessibility and user friendliness. If the probes are changed, steps
3.16.3.5 b. (1), (2), and (3) shall be repeated each time a change is made.
3.16.3.7
Marking and Recording of Inspection Results. Mark and record as required by paragraph 1.3.
3.16.4 Backup Method. Fluorescent Penetrant, refer to paragraph 1.4.7.
3.16.5 System Securing. If removed, the combining transmission requires installation as required in accordance with
the applicable technical manuals listed in Table 1-1. Secure the combiner transmission door.
AFT TRANSMISSION OUTSIDE SURFACE (ET).
3.17.1 Description (Figure 3-1. Index No. 17). The aft transmission receives input torque from the combining
transmission through the aft driveshafting. It transmits torque to the aft rotor shafting through a splined connection.
3.17.2 Defects. Defects may occur anywhere on the surface of the aft transmission outside surface. Any damaged
area shall be inspected both before and after rework. No cracks are allowed.
