Change 1 2-38.1
STRAP PACK OUTBOARD BOLT INSPECTION (UT)
188.8.131.52.1 Description. The four strap pack outboard bolts are made of PH13-8 MO steel and
are secured by a pin to the lead lag link and pitch housing.
184.108.40.206.2 Defects. This inspection is used to detect inside and outside diameter
circumferential cracks in the shank of the strap pack bolt.
220.127.116.11.3 Primary Method. Ultrasonic specific.
This inspection procedure and graphics shall be reviewed in its entirety prior to
performing the inspection. The supplemental training CD ROM should also be
reviewed in conjunction with performing this procedure.
18.104.22.168.3.1 NDI Equipment and Materials. (Refer to Appendix B)
a. Ultrasonic Inspection Unit, USD 15S/AF
b. Transducer, 15.0 MHz, longitudinal wave, 1/8 in. x 1/8 in. element
c. Transducer Positioner
d. Cable Assembly, BNC to Microdot
e. Consumable Materials, refer to Table 1-8
f. Aircraft Marking Pencil, refer to Table 1-8
22.214.171.124.3.2 Preparation of Helicopter. The helicopter shall be prepared for safe ground
maintenance. The lead lag link shall be removed in accordance with TM 1-1520-238-23.
126.96.36.199.3 Access. Access to the strap pack outboard bolt can be accomplished by removal
of the main rotor blade and the lead lag link in accordance with TM 1-1520-238-23.
188.8.131.52.3.4 Preparation of Part. The part shall be thoroughly cleaned. Refer to Preparation of
Part for NDI, paragraph 1.4.4.
Lead Lag Link
Pitch change housing
Strap Pack Outboard Bolt