TM 1-1520-265-23
Probe drive
- mid
LPF
- 100
HPF
-0
H Pos
- 80%
V Pos
- 20%
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. (See the standard instrument display shown in Figure
1-7.)
4.13.3.6
Inspection Procedure. Refer to Eddy Current Method, paragraph 1.4.11 and Figure 4-13.
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 are cause for rejection.
NOTE
Either probe identified in paragraph 4.13.3.1 may be used depending primarily on the ease of
accessibility and user friendliness. If the probes are changed, steps 4.13.3.5 b. (1), (2), and (3)
shall be repeated each time a change is made.
4.13.3.7
Marking and Recording of Inspection Results. Mark and record inspection results as required by paragraph
1.3.
4.13.4
Backup Method. None required.
4.13.5
System Securing. The cargo door, if removed, requires installation in accordance with the applicable technical
manuals listed in Table 1-1.
4.14
OIL COOLER COMPARTMENT ACCESS DOOR (PT).
4.14.1
Description (Figure 4-1. Index No. 14). The oil cooler compartment access door (provision 3T-25) is provided
to facilitate inspection and maintenance of the oil cooler.
4.14.2
Defects. This inspection is used to verify crack indications found visually on the door assembly. This
inspection includes the door hinges, catches, and fittings. No cracks are allowed.
4.14.3
Primary Method. Fluorescent Penetrant.
4-33
