TM 1-1520-265-23a.Select AC on the AC/DC power switch.b.Place probe/yoke on part in position 1 as shown.c.Press the test switch and apply a light coat of magnetic particle media at the same time. Remove the mediamomentarily before removing the current. Current should be applied for no more than five seconds.d.Inspect for cracks using the black light.e.Demagnetize before moving to the next position. Refer to paragraph 6.19.3.8.f.Repeat steps a. through e. for positions 2 through 5.6.19.3.7Marking and Recording of Inspection Results. Mark and record inspection results as required by paragraph 1.3.6.19.3.8 Demagnetization. With the switch remaining in the AC position, place the probe/yoke legs in the same positionused for magnetizing. Press the test switch and withdraw the probe/yoke from the part for a distance of two feet beforereleasing the switch.6.19.4 BackupMethod.None required.6.19.5 SystemSecuring.Clean the forward bellcrank thoroughly to remove all residual magnetic particle media. Referto Post Cleaning and Restoration of Part or Area After NDI, paragraph 1.4.16. The forward bellcrank, if removed,requires installation in accordance with the applicable technical manuals listed in Table 1-1.6.20 LATERAL BELLCRANK (MT).6.20.1 Description(Figure6-1.IndexNo.20).The lateral bellcrank, supported by the bellcrank support (bridge) inthe swashplate linkage installation, transfers flight control movements through a connecting servo link to the main rotorswashplate. It is machined from a 4340 steel forging, cadmium plated, and protected by epoxy primer and polyurethanepaint.6.20.2 Defects.This inspection is used to verify crack indications found visually on the lateral bellcrank. Inspect allreworked areas for cracks. Inspect lateral bellcrank lug and rib surfaces. Visually inspect bellcrank flanged pivotbushings. No cracks are allowed.6.20.3 PrimaryMethod.Magnetic Particle.6.20.3.1 NDI Equipment and Materials. (Refer to Appendix B.)a.Magnetic Particle Inspection Probe/Yokeb.Magnetometerc.Black Lightd.Fluorescent Magnetic Particles, refer to Table 1-8e.Consumable Materials, refer to Table 1-8f.Aircraft Marking Pencil, refer to Table 1-8NOTEHand-held magnetic coil may be used. Refer to paragraph 1.4.8.1.2 and Figure 1-6.6-39
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