Preparation of Helicopter. The helicopter shall be prepared for safe ground maintenance. 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 aft driveshafting tubes shall be removed in accordance with the
Access. Access is through the aft driveshafting baffle. See Figure 1-4 - CH-47: 45; MH-47: 33.
Use only appropriate platforrms, workstands, or other approved locally procured
stands and restraint equipment when working above 10 feet on helicopters in a
nontactical environment. Otherwise, personnel injury could result from accidental
Preparation of Part. The aft driveshafting tubes shall be thoroughly cleaned. Refer to
NDI Equipment Settings.
Make the following initial settings on the Eddy Current Inspection Unit, NORTEC-19e .
- 200 KHz
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 (Refer to standard instrument display shown
Place probe on part in the required inspection location and null.
Adjust phase as required to obtain
Inspect the part.
Any signal similar to the notches in the test block is cause for rejection.