5.10 ENGINE LOAD DEMAND SPINDLE BELLCRANK SUPPORT (ET).
Description (Figure 5-1. Index No. 10)
. This support is located on the transmission bay dock, just forward of
the transmission. It is the point at which three systems join. It ties the engines (torque sensing) to the flight controls
(pilot/CPG's collectives) and is mounted in the main part of the airframe.
Defects. This inspection is used to verify crack indications found visually on the support. No cracks are
Primary Method. Eddy Current.
126.96.36.199 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
188.8.131.52 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 support shall be removed in accordance with the applicable
technical manuals listed in Table 1-1.
184.108.40.206 Access. Access is through access panels (Figure 1-4, Items L200 and R200).
220.127.116.11 Preparation of Part. The part shall be thoroughly cleaned. Refer to Preparation of Part or Area for NDI,
18.104.22.168 NDI Equipment Settings.
Make the following initial settings on the Eddy Current Inspection Unit, NORTEC-19e
- 200 KHz
Refer to Eddy Current Method, paragraph 1.4.11. Set up on test block as follows:
Null probe on test block.
Adjust phase as required to obtain horizontal lift-off.
Move probe over all three notches in test block. Adjust gain to obtain a three block vertical signal when
probe is passed over 0.040-inch notch in test block. (See the standard instrument display shown in Figure