TM 1-1520-265-23
Change 2 5-17
5.9 CROTCH ASSEMBLY AND SEGMENT RING (PT).
5.9.1 Description (Figure 5-1, Index No. 9). The crotch assembly is mounted around the forward
support tube and is attached to the engine swirl frame with a sealed firewall plate.
5.9.2 Defects. This Inspection is to be used to confirm suspect crack indications detected visually
through the casting. No cracks are allowed.
5.9.3 Primary Method. Flourescent Penetrant.
5.9.3.1 NDI Equipment and Materials. (Refer to Appendix B.)
a. Flourescent Penetrant Inspection Kit
b. Black Light UV Kit
5.9.3.2 Preparation of Helicopter. The helicopter shall be prepared for safe ground maintenance and
the crotch assembly removed in accordance with the applicable technical manuals listed in Table 1-1.
5.9.3.3 Access. Not applicable.
5.9.3.4 Preparation of Part. The part shall be thoroughly cleaned. Refer to Preparation of Part or
Area for NDI, paragraph 1.4.4.
5.9.3.5Deleted.
5.9.3.6Inspection Procedure.
Perform the Flourescent Penetrant Inspection. Refer to the
Flourescent Penetrant Method, paragraph 1.4.7 and Table 1--5. Inspect area of concern.
5.9.3.7 Marking and Recording of Inspection Results. Mark and record inspection results as
required by paragraph 1.3.
5.9.3.8Backup Method. None required.
5.9.3.9System Securing. Clean the part area to remove the inspection media. Refer to the post
cleaning and restoration of part or area after NDI paragraph 1.4.16. Protective coatings shall be
applied as required. Parts or components if removed or disassembled, required installation or
reassembly in accordance with the applicable technical manuals listed in Table 1--1..
5.9.4 Deleted.
5.9.5 Deleted.
