TM 1-1520-264-23
2.6.4
Backup Method. None required.
2.6.5
System Securing. The main rotor blade shall be cleaned as necessary. Refer to Post Cleaning and Restoration
of Part or Area after NDI, paragraph 1.4.1.6. The main rotor blade, if off the helicopter, requires reinstallation in
accordance with the applicable technical manual listed in Table 1-1.
2.7
MAIN ROTOR BLADE WEIGHT SUPPORT FITTINGS (ET).
2.7.1
Description (Figure 2-1. Index No. 7). The main rotor blade weight support fittings are located within the swept
back tip. The fitting supports the weight used when balancing the blade.
2.7.2
Defects. This inspection is used to verify crack indications found visually on the main rotor blade weight support
fitting. No cracks are allowed.
2.7.3
Primary Method. Eddy Current.
2.7.3.1 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.
Reference Block, three-notched titanium (0.008, 0.020, and 0.040 EDM notches)
g.
Teflon Tape, refer to Table 1-8
h.
Aircraft Marking Pencil, refer to Table 1-8
2.7.3.2 Preparation of Helicopter. The helicopter shall be prepared for safe ground maintenance. A partial inspection for
cause (visual indications, sites of mechanical damage, corrosion, etc.) may be performed on all exposed surfaces of the
installed part using this procedure in accordance with the applicable technical manuals listed in Table 1-1.
2.7.3.3 Access. Tip cap removed.
Maintenance Platforms/Workstands
Use only appropriate platforms, workstands, or other approved locally procured stands
and restraint equipment when working above 10 feet on helicopter in a nontactical
environment. Otherwise, personnel injury could result from accidental falls.
2.7.3.4 Preparation of Part. The part shall be thoroughly cleaned. Refer to Preparation of Part or Area for NDI,
paragraph 1.4.4.
2-17
