TM 1-1520-253-23
FIRESHIELD SECTION (PT).
5.12.1 Description (Figure 5-1, Index No. 12). The fireshield attaches to the aft end of the combus-
tion chamber.
5.12.2 Defects. Inspect to verify cracks found visually.
5.12.3 Primary Method. Fluorescent Penetrant.
5.12.3.1 NDI Equipment and Materials. Inspection equipment shall be selected from the approved
list in Table 1-7, and AMS-2644 level 3 penetrant materials shall be selected from the approved list
in Table 1-8. Parts requiring fluorescent penetrant inspection shall be cleaned prior to inspection
with n-Propyl Bromide (vapor degreasing only) (Table 1-8), DS-108 (Table 1-8). DS-108, Electron,
Positron must be followed by an Acetone (Table 1-8) or Isopropyl Alcohol (Table 1-8) rinse or wipe;
or drying until there is no visible solvent residue left on parts.
5.12.3.2 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
fireshield shall be removed in accordance with the applicable manuals listed in Table 1-1.
5.12.3.3 Access. Not applicable.
5.12.3.4 Preparation of Part. Refer to Preparation of Part or Area for NDI, paragraph 1.4.4.
5.12.3.5 Inspection Procedure. Perform fluorescent penetrant inspection. Refer to Fluorescent
Penetrant Method, paragraph 1.4.7 and Table 1-4. Inspect area of concern. See Figure 5-12.
5.12.3.6 Marking and Recording of Inspection Results. Mark and record as required by paragraph
5.12.4 Backup Method. None required.
5.12.5 System Securing. Clean the fireshield section to remove inspection media. Refer to Post
Cleaning and Restoration of Part or Area After NDI, paragraph 1.4.16. The fireshield section, if
removed, requires installation in accordance with the applicable technical manuals listed in
Change 1
