TM 1-1520-264-23
3.13.4
Backup Method. None required.
3.13.5
System Securing. The main transmission, if removed, requires installation in accordance with the applicable
technical manuals listed in Table 1-1.
3.14
MAIN TRANSMISSION COMPRESSOR DRIVE ADAPTER (ET).
3.14.1
Description (Figure 3-1. Index No. 14). The main transmission compressor drive adapter provides for
attachment of the main transmission to the shaft drive compressor.
3.14.2
Defects. This inspection is used to verify crack indications found visually on the main transmission compressor
drive adapter. No cracks are allowed.
3.14.3
Primary Method. Eddy Current.
3.14.3.1 NDI Equipment and Materials. (Refer to Appendix B.)
a.
Eddy Current Inspection Unit
b.
Probe, straight, shielded surface, 100 KHz-500 KHz
c.
Probe, right angle, shielded surface, 100 KHz-500 KHz, 90 1/2 inch drop
d.
Cable Assembly
e.
Reference Block, three-notched aluminum (0.008, 0.020, and 0.040 EDM notches)
f.
Teflon Tape, refer to Table 1-8
g.
Aircraft Marking Pencil, refer to Table 1-8
3.14.3.2 Preparation of Helicopter. The helicopter shall be prepared for safe ground maintenance and the main
transmission compressor drive adapter removed in accordance with the applicable technical manuals listed in Table 1-1.
3.14.3.3 Access. Not applicable.
3.14.3.4 Preparation of Part. The part shall be thoroughly cleaned. Refer to Preparation of Part or Area for NDI,
paragraph 1.4.4.
3.14.3.5 NDI Equipment Settings.
a.
Make the following initial settings on the Eddy Current Inspection Unit, NORTEC-19eII
Frequency F1
- 200 KHz
F2
-off
HdB
- 57.0
VdB
- 69.0
Rot
- 56
Probe drive
- mid
LPF
- 100
HPF
- 0
H Pos
- 80%
V Pos
- 20%
3-32
