Press the test switch and apply a light coat of magnetic particle media at the same time.
Remove the media momentarily before removing the current. Current should be applied for no more than five
Inspect for cracks using the black light.
Marking and Recording of Inspection Results. Mark and record the. inspection results as required by
Demagnetization. With the switch remaining in the AC position, place the probe/yoke legs in the same
position used for magnetizing. Press the test switch and withdraw the probe/yoke from the part for a distance of two feet
before releasing the switch.
Backup Method. None required.
System Securing. Clean the main rotor damper rod end thoroughly to remove all residual magnetic particle
media. Refer to Post Cleaning and Restoration of Part or Area After NDI, paragraph 1.4.16. The main rotor damper rod
end, if removed, requires installation in accordance with the applicable technical manuals listed in Table 1-1.
2.16 MAIN ROTOR PITCH HOUSING (ET).
Description (Figure 2-1. Index No. 16). The main rotor pitch housing assembly control inputs
to course angle changes on the main rotor blade assembly.
Defects. This inspection is used to verify crack indications found visually on the main rotor pitch housing. No
cracks are allowed.
Primary Method. Eddy Current.
NDI Equipment and Materials. (Refer to Appendix B.)
Eddy Current Inspection Unit
Probe, straight, shielded surface, 100 KHz-500 KHz
Probe, right angle, shielded surface, 100 KHz-500 KHz, 90 °
1/2 inch drop
Reference Block, three-notched aluminum (0.008, 0.020, and 0.040 EDM notches)
Teflon Tape, refer to Table 1-8
Aircraft Marking Pencil, refer to Table 1-8
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. If required, the main rotor pitch housing shall be removed in accordance with the
applicable technical manuals listed in Table 1-1.
Access. Not applicable.
Preparation of Part. The part shall be thoroughly cleaned. Refer to Preparation of Part or Area for NDI,