Figure 6-18. Walking Beam
6.18.4 Backup Method. None required.
6.18.5 System Securing. Clean the walking beam 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 walking beam, if removed, requires
installation in accordance with the applicable technical manuals listed in Table 1-1.
6.19 FORWARD BELLCRANK (MT).
6.19.1 Description (Figure 6-1, Index No. 19). The forward bellcrank, supported by the bellcrank support (bridge) in
the swashplate linkage installation, transfers flight control movements through a connecting servo link to the main rotor
swashplate. It is machined from a 4340 steel forging, cadmium plated, and protected by epoxy primer and polyurethane
6.19.2 Defects. This inspection is used to verify crack indications found visually on the forward bellcrank. Inspect all
reworked areas for cracks. Inspect forward bellcrank lug and rib surfaces. Visually inspect bellcrank flanged pivot
bushings. No cracks are allowed.
6.19.3 Primary Method. Magnetic Particle.
188.8.131.52 NDI Equipment and Materials. (Refer to Appendix B.)
Magnetic Particle Inspection Probe/Yoke